Resource Recovery Technology Application Document.

DTIC Science & Technology

1982-06-01

B-6 Electrostatic Precipitator (APC-C) ......................B-1O Venturi Scrubber (APC D) B-15 C Combustion Equipment (CE) C-1 Modular... Scrubber APC-D P. 1 of 4 CONTROLIII COMPONENT DESCRIPTION Types Available - Competing Components Type a. Venturi e. Moving bed Venturi b. Flooded disc f...Clean Gas to Demister (Used Separate Liquid from Gas Stream) / F C Scrubber Wall Liquid Inlet D Scrubber Liquid at Venturi Throat Inlet B E Venturi

KSC-07pd0851

NASA Image and Video Library

2007-04-10

KENNEDY SPACE CENTER, FLA. -- Two trucks (one air-ride, one flat-bed) deliver the Dawn spacecraft, as well as additional electrical and ground support equipment and xenon ground support equipment, to Astrotech. Dawn will be moved from the truck and the shipping container removed. The spacecraft will then be moved into the high bay of the Payload Processing Facility. Dawn's mission is to explore two of the asteroid belt's most intriguing and dissimilar occupants: asteroid Vesta and the dwarf planet Ceres. The Dawn mission is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate in Washington, D.C. Photo credit: NASA/Jim Grossmann

Early processing variations in selective attention to the color and direction of moving stimuli during 30 days head-down bed rest

NASA Astrophysics Data System (ADS)

Wang, Lin-Jie; He, Si-Yang; Niu, Dong-Bin; Guo, Jian-Ping; Xu, Yun-Long; Wang, De-Sheng; Cao, Yi; Zhao, Qi; Tan, Cheng; Li, Zhi-Li; Tang, Guo-Hua; Li, Yin-Hui; Bai, Yan-Qiang

2013-11-01

Dynamic variations in early selective attention to the color and direction of moving stimuli were explored during a 30 days period of head-down bed rest. Event-related potentials (ERPs) were recorded at F5, F6, P5, P6 scalp locations in seven male subjects who attended to pairs of bicolored light emitting diodes that flashed sequentially to produce a perception of movement. Subjects were required to attend selectively to a critical feature of the moving target, e.g., color or direction. The tasks included: a no response task, a color selective response task, a moving direction selective response task, and a combined color-direction selective response task. Subjects were asked to perform these four tasks on: the 3rd day before bed rest; the 3rd, 15th and 30th day during the bed rest; and the 5th day after bed rest. Subjects responded quickly to the color than moving direction and combined color-direction response. And they had a longer reaction time during bed rest on the 15th and 30th day during bed rest after a relatively quicker response on the 3rd day. Using brain event-related potentials technique, we found that in the color selective response task, the mean amplitudes of P1 and N1 for target ERPs decreased in the 3rd day during bed rest and 5th day after bed rest in comparison with pre-bed rest, 15th day and 30th day during bed rest. In the combined color-direction selective response task, the P1 latencies for target ERPs on the 3rd and 30th day during bed rest were longer than on the 15th day during bed rest. As 3rd day during bed rest was in the acute adaptation period and 30th day during bed rest was in the relatively adaptation stage of head-down bed rest, the results help to clarify the effects of bed rest on different task loads and patterns of attention. It was suggested that subjects expended more time to give correct decision in the head-down tilt bed rest state. A difficulty in the recruitment of brain resources was found in feature selection task, but no variations were detected in the no response and direction selective response tasks. It is suggested that the negative shift in color selective response task on the 3rd day of bed rest are a result of fluid redistribution. And feature selection was more affected than motion selection in the head down bed rest. The variations in cognitive processing speed observed for the combined color-direction selective response task are suggested to reflect the interaction between top-down mechanisms and hierarchical physiological characteristics during 30 days head-down bed rest.

Rapid Cycle Amine (RCA) 3.0 System Development

NASA Technical Reports Server (NTRS)

Chullen, Cinda; Campbell, Colin; Papale, William; Hawes, Kevin; Wichowski, Robert

2015-01-01

The Rapid Cycle Amine (RCA) 3.0 system is currently under development by NASA, the Lyndon B. Johnson Space Center (JSC) in conjunction with United Technologies Corporation Aerospace Systems (UTAS). The RCA technology is a new carbon dioxide (CO2) and humidity removal system that has been baselined for the Advanced Extravehicular Mobility Unit (AEMU) Portable Life Support System. The evolution of the RCA development has progressed through several iterations of technology readiness levels including RCA 1.0, RCA 2.0, and RCA 3.0 test articles. The RCA is an advancement over currently technologies due to its unique regeneration capability. The RCA is capable of simultaneously removing CO2 and humidity from an influent air steam and subsequent regeneration when exposed to a vacuum source. The RCA technology uses two solid amine sorbent beds in an alternating fashion to adsorb CO2 and water (uptake mode) and desorb CO2 and water (regeneration mode) at the same time. The two beds operate in an efficient manner so that while one bed is in the uptake mode, the other is in the regeneration mode, thus continuously providing an on-service sorbent bed by which CO2 and humidity may be removed. The RCA 2.0 and 3.0 test articles were designed with a novel valve assembly which allows for switching between uptake and regeneration modes with only one moving part while minimizing gas volume losses to the vacuum source by means of an internal pressure equalization step during actuation. The RCA technology also is low power, small, and has performed extremely well in all development testing thus far. A final design was selected for the RCA 3.0, fabricated, assembled, and performance tested in 2014 with delivery to NASAJSC in January 2015. This paper will provide an overview on the RCA 3.0 system design and results of pre-delivery testing with references to the development of RCA 1.0 and RCA 2.0.

Simulated Moving Bed Chromatography: Separation and Recovery of Sugars and Ionic Liquid from Biomass Hydrolysates

PubMed Central

Caes, Benjamin R.; Van Oosbree, Thomas R.; Lu, Fachuang; Ralph, John; Maravelias, Christos T.

2015-01-01

Simulated moving bed chromatography, a continuous separation method, enables the nearly quantitative recovery of sugar products and ionic liquid solvent from chemical hydrolysates of biomass. The ensuing sugars support microbial growth, and the residual lignin from the process is intact. PMID:23939991

Computational Study of Colloidal Droplet Interactions with Three Dimensional Structures

DTIC Science & Technology

2015-05-18

on the meshless SPH method for droplet impact on and sorption into a powder bed considering free surface flow above the powder bed surface ...considering free surface flow above the powder bed surface , infiltration of the liquid in the porous matrix, and the interfacial forces on the free moving...infiltration of the liquid in the porous matrix, and the interfacial forces on the free moving surface . The model has been used to study the effect of impact

Evaluation of ADCP apparent bed load velocity in a large sand-bed river: Moving versus stationary boat conditions

USGS Publications Warehouse

Jamieson, E.C.; Rennie, C.D.; Jacobson, R.B.; Townsend, R.D.

2011-01-01

Detailed mapping of bathymetry and apparent bed load velocity using a boat-mounted acoustic Doppler current profiler (ADCP) was carried out along a 388-m section of the lower Missouri River near Columbia, Missouri. Sampling transects (moving boat) were completed at 5- and 20-m spacing along the study section. Stationary (fixed-boat) measurements were made by maintaining constant boat position over a target point where the position of the boat did not deviate more than 3 m in any direction. For each transect and stationary measurement, apparent bed load velocity (vb) was estimated using ADCP bottom tracking data and high precision real-time kinematic (RTK) global positioning system (GPS). The principal objectives of this research are to (1) determine whether boat motion introduces a bias in apparent bed load velocity measurements; and (2) evaluate the reliability of ADCP bed velocity measurements for a range of sediment transport environments. Results indicate that both high transport (vb>0.6 m/s) and moving-boat conditions (for both high and low transport environments) increase the relative variability in estimates of mean bed velocity. Despite this, the spatially dense single-transect measurements were capable of producing detailed bed velocity maps that correspond closely with the expected pattern of sediment transport over large dunes. ?? 2011 American Society of Civil Engineers.

An audit of the use of isolation facilities in a UK National Health Service trust.

PubMed

Damji, S; Barlow, G D; Patterson, L; Nathwani, D

2005-07-01

To aid the ongoing battle against hospital-acquired infection in the UK, all acute National Health Service (NHS) trusts should have audit data about how dedicated isolation beds within the trust are being used. In a previously published audit, we demonstrated that one-third of patients admitted to a dedicated isolation room in Tayside were not thought to be an infection risk by experienced healthcare staff. Since this audit, Tayside's isolation facilities have moved from a small peripheral 'fever' hospital to a large central teaching hospital site. At the time of this move, and using the above audit data, we designed and implemented a guideline for general practitioners and hospital doctors regarding the admission of patients to an isolation bed. The aim of this study was to compare the use of isolation beds before and after the move to the new facilities, which we anticipated would increase the demand for isolation. The results show that by all three criteria used, the utilization of isolation beds has deteriorated following the move, mainly due to the increased admission of general medical 'boarders' and low-risk infection patients. At a time when hospital-acquired infections are increasing, NHS trusts should ensure that dedicated isolation beds are used appropriately.

Bed Bugs and Schools

EPA Pesticide Factsheets

Bed bugs have long been a pest – feeding on blood, causing itchy bites and generally irritating their human hosts. They are successful hitchhikers, and can move from an infested site to furniture, bedding, baggage, boxes, and clothing.

Method and apparatus for filtering gas with a moving granular filter bed

DOEpatents

Brown, Robert C.; Wistrom, Corey; Smeenk, Jerod L.

2007-12-18

A method and apparatus for filtering gas (58) with a moving granular filter bed (48) involves moving a mass of particulate filter material (48) downwardly through a filter compartment (35); tangentially introducing gas into the compartment (54) to move in a cyclonic path downwardly around the moving filter material (48); diverting the cyclonic path (58) to a vertical path (62) to cause the gas to directly interface with the particulate filter material (48); thence causing the gas to move upwardly through the filter material (48) through a screened partition (24, 32) into a static upper compartment (22) of a filter compartment for exodus (56) of the gas which has passed through the particulate filter material (48).

Influence of filling ratio and carrier type on organic matter removal in a moving bed biofilm reactor with pretreatment of electrocoagulation in wastewater treatment.

PubMed

Lopez-Lopez, C; Martín-Pascual, J; González-Martínez, A; Calderón, K; González-López, J; Hontoria, E; Poyatos, J M

2012-01-01

At present, there is great concern about limited water resources and water quality, which require a more advanced technology. The Moving Bed Biofilm Reactor (MBBR) has been shown to be an efficient technology for removal of organic matter and nutrients in industrial and urban wastewater treatment. However, there are some pollutants which are more difficult to remove by biological processes, so this process can be improved with additional physical and chemical treatments such as electrocoagulation, which appears to be a promising technology in electrochemical treatments. In this research, urban wastewater was treated in an MBBR plant with an electrocoagulation pre-treatment. K1 from AnoxKaldnes and AQWISE ABC5 from Aqwise were the carriers studied under three different filling ratios (20, 35, and 50%). The experimental pilot plant had four bioreactors with 20 L of operation volume and a common feed tank with 100 L of operation volume. The movement of the carriers was generated by aeration and stirrer systems. Organic matter removal was studied by analysis of soluble chemical oxygen demand (sCOD). The maximum organic matter removal in this MBBR system was 65.8% ± 1.4% and 78.4% ± 0.1% for K1 and Aqwise ABC5 carriers, respectively. Moreover, the bacterial diversity of the biofilm was studied by temperature-gradient gel electrophoresis (TGGE) of PCR-amplified partial 16S rRNA genes. 20 prominent TGGE bands were successfully reamplified and sequenced, being the predominant population: β-Proteobacteria, α-Proteobacteria, and Actinobacteria.

AORN ergonomic tool 1: Lateral transfer of a patient from a stretcher to an OR bed.

PubMed

Waters, Thomas; Baptiste, Andrea; Short, Manon; Plante-Mallon, Lori; Nelson, Audrey

2011-03-01

Moving patients can result in injuries to patients and staff members. Lateral patient transfers from a stretcher to an OR bed pose a high risk for musculoskeletal disorders, including lower back, shoulder, and neck injuries for perioperative personnel. AORN Ergonomic Tool 1: Lateral Transfer of a Patient from a Stretcher to an OR Bed helps perioperative staff members determine best practices for safe lateral patient transfers. Safe moving of the patient is determined by the starting and ending position required and the patient's weight. Current ergonomic safety concepts and scientific evidence regarding weight limits help to determine how many caregivers are needed to safely move patients and whether mechanical assistance is needed during lateral transfers. Published by Elsevier Inc.

An Intelligent Robotic Hospital Bed for Safe Transportation of Critical Neurosurgery Patients Along Crowded Hospital Corridors.

PubMed

Wang, Chao; Savkin, Andrey V; Clout, Ray; Nguyen, Hung T

2015-09-01

We present a novel design of an intelligent robotic hospital bed, named Flexbed, with autonomous navigation ability. The robotic bed is developed for fast and safe transportation of critical neurosurgery patients without changing beds. Flexbed is more efficient and safe during the transportation process comparing to the conventional hospital beds. Flexbed is able to avoid en-route obstacles with an efficient easy-to-implement collision avoidance strategy when an obstacle is nearby and to move towards its destination at maximum speed when there is no threat of collision. We present extensive simulation results of navigation of Flexbed in the crowded hospital corridor environments with moving obstacles. Moreover, results of experiments with Flexbed in the real world scenarios are also presented and discussed.

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, W.C.; Newby, R.A.; Lippert, T.E.

1997-08-05

The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The fly ash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured fly ash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled. 11 figs.

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, Wen-Ching; Newby, Richard A.; Lippert, Thomas E.

1997-01-01

The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The flyash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured flyash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled.

Thermal energy storage for solar power generation - State of the art

NASA Astrophysics Data System (ADS)

Shukla, K. N.

1981-12-01

High temperature storage for applications in solar-thermal electric systems is considered. Noting that thermal storage is in either the form of latent, sensible or chemically stored heat, sensible heat storage is stressed as the most developed of the thermal storage technologies, spanning direct heating of a storage medium from 120-1250 C. Current methods involve solids, packed beds, fluidized beds, liquids, hot water, organic liquids, and inorganic liquids and molten salts. Latent heat storage comprises phase-change materials that move from solid to liquid with addition of heat and liquid to solid with the removal of heat. Metals or inorganic salts are candidates, and the energy balances are outlined. Finally, chemical heat storage is examined, showing possible high energy densities through catalytic, thermal dissociation reactions.

Evaluation of three types of structured floating plastic media in moving bed biofilters for total ammonia nitrogen removal in a low salinity hatchery recirculating aquaculture system

USDA-ARS?s Scientific Manuscript database

Three different commercially available structural plastic media were evaluated in triplicate in moving bed toriod filters under low salinity (11-12 ppt) warm water culture conditions and two different feed loading rates. The culture system consisted of nine separate modules that include a double dra...

Application of a Line Laser Scanner for Bed Form Tracking in a Laboratory Flume

NASA Astrophysics Data System (ADS)

de Ruijsscher, T. V.; Hoitink, A. J. F.; Dinnissen, S.; Vermeulen, B.; Hazenberg, P.

2018-03-01

A new measurement method for continuous detection of bed forms in movable bed laboratory experiments is presented and tested. The device consists of a line laser coupled to a 3-D camera, which makes use of triangulation. This allows to measure bed forms during morphodynamic experiments, without removing the water from the flume. A correction is applied for the effect of laser refraction at the air-water interface. We conclude that the absolute measurement error increases with increasing flow velocity, its standard deviation increases with water depth and flow velocity, and the percentage of missing values increases with water depth. Although 71% of the data is lost in a pilot moving bed experiment with sand, still high agreement between flowing water and dry bed measurements is found when a robust LOcally weighted regrESSion (LOESS) procedure is applied. This is promising for bed form tracking applications in laboratory experiments, especially when lightweight sediments like polystyrene are used, which require smaller flow velocities to achieve dynamic similarity to the prototype. This is confirmed in a moving bed experiment with polystyrene.

Method and system for continuous atomic layer deposition

DOEpatents

Elam, Jeffrey W.; Yanguas-Gil, Angel; Libera, Joseph A.

2017-03-21

A system and method for continuous atomic layer deposition. The system and method includes a housing, a moving bed which passes through the housing, a plurality of precursor gases and associated input ports and the amount of precursor gases, position of the input ports, and relative velocity of the moving bed and carrier gases enabling exhaustion of the precursor gases at available reaction sites.

A comparative assessment of waste incinerators in the UK.

PubMed

Nixon, J D; Wright, D G; Dey, P K; Ghosh, S K; Davies, P A

2013-11-01

The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supply chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87-92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management. Copyright © 2013 Elsevier Ltd. All rights reserved.

Valorisation of waste tyre by pyrolysis in a moving bed reactor.

PubMed

Aylón, E; Fernández-Colino, A; Murillo, R; Navarro, M V; García, T; Mastral, A M

2010-07-01

The aim of this work is to assess the behaviour of a moving bed reactor, based on a screw transporter design, in waste tyre pyrolysis under several experimental conditions. Waste tyre represents a significant problem in developed countries and it is necessary to develop new technology that could easily process big amounts of this potentially raw material. In this work, the influence of the main pyrolysis process variables (temperature, solid residence time, mass flow rate and inert gas flow) has been studied by a thorough analysis of product yields and properties. It has been found that regardless the process operational parameters, a total waste tyre devolatilisation is achieved, producing a pyrolytic carbon black with a volatile matter content under 5 wt.%. In addition, it has been proven that, in the range studied, the most influencing process variables are temperature and solid mass flow rate, mainly because both variables modify the gas residence time inside the reactor. In addition, it has been found that the modification of these variables affects to the chemical properties of the products. This fact is mainly associated to the different cracking reaction of the primary pyrolysis products. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Valorisation of waste tyre by pyrolysis in a moving bed reactor

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

Aylon, E.; Fernandez-Colino, A.; Murillo, R., E-mail: ramonm@icb.csic.e

2010-07-15

The aim of this work is to assess the behaviour of a moving bed reactor, based on a screw transporter design, in waste tyre pyrolysis under several experimental conditions. Waste tyre represents a significant problem in developed countries and it is necessary to develop new technology that could easily process big amounts of this potentially raw material. In this work, the influence of the main pyrolysis process variables (temperature, solid residence time, mass flow rate and inert gas flow) has been studied by a thorough analysis of product yields and properties. It has been found that regardless the process operationalmore » parameters, a total waste tyre devolatilisation is achieved, producing a pyrolytic carbon black with a volatile matter content under 5 wt.%. In addition, it has been proven that, in the range studied, the most influencing process variables are temperature and solid mass flow rate, mainly because both variables modify the gas residence time inside the reactor. In addition, it has been found that the modification of these variables affects to the chemical properties of the products. This fact is mainly associated to the different cracking reaction of the primary pyrolysis products.« less

The use of moving bed bio-reactor to laundry wastewater treatment

NASA Astrophysics Data System (ADS)

Bering, Sławomira; Mazur, Jacek; Tarnowski, Krzysztof; Janus, Magdalena; Mozia, Sylwia; Waldemar Morawski, Antoni

2017-11-01

Large laboratory scale biological treatment test of industrial real wastewater, generated in industrial big laundry, has been conducted in the period of May 2016-August 2016. The research aimed at selection of laundry wastewater treatment technology included tests of two-stage Moving Bed Bio Reactor (MBBR), with two reactors filled with carriers Kaldnes K5 (specific area - 800 m2/m3), have been realized in aerobic condition. Operating on site, in the laundry, reactors have been fed real wastewater from laundry retention tank. To the laundry wastewater, contained mainly surfactants and impurities originating from washed fabrics, a solution of urea to supplement nitrogen content and a solution of acid to correct pH have been added. Daily flow of raw wastewater Qd was equal to 0.6-0.8 m3/d. The values of determined wastewater quality indicators showed that substantial decrease of pollutants content have been reached: BOD5 by 94.7-98.1%, COD by 86.9-93.5%, the sum of anionic and nonionic surfactants by 98.7-99.8%. The quality of the purified wastewater, after star-up period, meets the legal requirements regarding the standards for wastewater discharged to the environment.

The application of moving bed bio-reactor (MBBR) in commercial laundry wastewater treatment.

PubMed

Bering, Sławomira; Mazur, Jacek; Tarnowski, Krzysztof; Janus, Magdalena; Mozia, Sylwia; Morawski, Antoni Waldemar

2018-06-15

Large, laboratory scale biological treatment tests of real industrial wastewater, generated in a large industrial laundry facility, was conducted from October 2014 to January 2015. This research sought to develop laundry wastewater treatment technology which included tests of a two-stage Moving Bed Bio Reactor (MBBR); this had two reactors, was filled with carriers Kaldnes K5 (specific area - 800 m 2 /m 3 ) and were realized in aerobic condition. Operating on site, in the laundry, reactors were fed actual wastewater from the laundry retention tank. The laundry wastewater contained mainly surfactants and impurities originating from washed fabrics; a solution of urea to supplement nitrogen content and a solution of acid to correct pH were added. The daily flow of raw wastewater Qd varied from 0.6-1.0 m 3 /d. Wastewater quality indicators showed that the reduction of pollutants was obtained: BOD 5 by 95-98%, COD by 89-94%, the sum of anionic and nonionic surfactants by 85-96%. The quality of the purified wastewater after the start-up period met legal requirements regarding the standards for wastewater discharged into the environment. Copyright © 2018 Elsevier B.V. All rights reserved.

Cyclic Steps and Antidunes : Relating Their Features to a Suspension Index

NASA Astrophysics Data System (ADS)

Yokokawa, M.; Kishima, Y.; Parker, G.

2010-12-01

Cyclic Steps and Antidunes : Relating Their Features to a Suspension Index Miwa Yokokawa (1), Yasushi Kishima (1), Gary Parker (2, 3) 1: Osaka Institute of Technology, Hirakata, Osaka, Japan 2: Dept. of Civil & Environmental Engineering, University of Illinois, Urbana, Illinois, U.S.A. 3: Dept. of Geology, University of Illinois, Urbana, Illinois, U.S.A. There are very few comparative studies of the differences in hydraulic conditions and morphologic features of bed- and water-surface-waves associated with cyclic steps and antidunes. In this study, the features of both the bed and the water surface, as well as hydraulic conditions are examined over the spectrum from antidune to cyclic steps. Experiments were performed using a flume at the Osaka Institute of Technology. The resultant features of the bedforms are as follows. In the case of antidunes, bed waves and water surface waves are in phase except when they collapse. Antidunes show several kinds of behavior; migrating downstream, standing, or migrating upstream. Upstream-migrating antidunes are divided into non-breaking, and breaking-types. Breaking antidunes appear alternatively with the plane bed state. Cyclic steps migrate upstream regularly associated with trains of hydraulic jumps, which divide each step. There is a significant change in water depth at the hydraulic jump, so that the phasing between the bed waves and water surface waves break at the each hydraulic jump. There is a kind of compromise between cyclic steps and antidunes, which we designate as “intermediate steps”. They move upstream and are associated with regular trains of hydraulic jumps. The jumps, however, occasionally collapse toward upstream. When this happens, bed waves move rapidly upstream; low-amplitude water surface waves and bed waves become in phase all over the bed shortly after the collapse. Then after some time, water surface waves become sufficiently prominent to yield regular hydraulic jumps. This cycle is then repeated.The hydraulic conditions for these bedfoms were examined using three non-dimensional parameters, i.e. the Froude Number, the Suspension Index, and the dimensionless particle size. The suspension index is a newly introduced parameter which is the ratio of the shear velocity divided by the settling velocity of the sediment (u*/Vs). Data from previous experimental studies are examined together with the present data in studying the characteristic regimes of bedform formation. In a diagram of Froude Number v.s. Suspension Index, antidunes, intermediate steps and cyclic steps can be divided along the axis of the Suspension Index. In the lowest range of the suspension index, downstream-migrating antidunes and upstream-migrating antidunes that do not break are found. The intermediate steps discussed above are located in the middle range. The highest range corresponds to cyclic steps and breaking antidunes. As described above, the Suspension Index can serve as a scale to quantify the spectrum between antidunes and cyclic steps. The use of the parameter also helps verify that suspension plays an important role in the formation and maintenance of cyclic steps.

Unusual seismogenic soft-sediment deformation structures in Cambrian epicratonic carbonate deposits, western Colorado, U.S.A

NASA Astrophysics Data System (ADS)

Myrow, P.; Chen, J.

2013-12-01

A wide variety of unusual penecontemporaneous deformation structures exist in grainstone and flat-pebble conglomerate beds of the Upper Cambrian strata, western Colorado, including slide scarps, thrusted beds, irregular blocks and internally deformed beds. Slide scarps are characterized by concave-up, sharp surfaces that truncate one or more underlying beds. Thrusted beds record movement of a part of a bed onto itself along a moderate to steeply inclined (generally 25°-40°) ramp. The hanging wall lenses in cases show fault-bend geometries, with either intact or mildly deformed bedding. Irregular bedded to internally deformed blocks isolated on generally flat upper bedding surfaces are similar in composition to the underlying beds. These features represent parts of beds that were detached, moved up onto, and some distances across, the laterally adjacent undisturbed bed surfaces. The blocks moved either at the sediment-water interface or intrastratally at shallow depths within overlying muddy deposits. Finally, internally deformed beds have large blocks, fitted fabrics of highly irregular fragments, and contorted lamination, which represent heterogeneous deformation, such as brecciation and liquefaction. The various deformation structures were most probably triggered by earthquakes, considering the nature of deformation (regional distribution of liquefaction structures, and the brittle segmentation and subsequent transportation of semi-consolidated beds) and the reactivation of Mesoproterozoic, crustal-scale shear zones in the central Rockies during the Late Cambrian. Features produced by initial brittle deformation are unusual relative to most reported seismites, and may represent poorly recognized to unrecognized seismogenic structures in the rock record.

Treatment of synthetic refinery wastewater in anoxic-aerobic sequential moving bed reactors and sulphur recovery.

PubMed

Mallick, Subrat Kumar; Chakraborty, Saswati

2017-11-10

Objective of the present study was to simultaneously biodegrade synthetic petroleum refinery wastewater containing phenol (750 mg/L), sulphide (750 mg/L), hydrocarbon (as emulsified diesel of 300 mg/L), ammonia-nitrogen (350 mg/L) at pH >9 in anoxic-aerobic sequential moving bed reactors. The optimum mixing speed of anoxic reactor was observed at 20 rpm and beyond that, removal rate remained constant. In anoxic reactor the minimum hydraulic retention time was observed to be 2 days for complete removal of sulphide, 40-50% removal of phenol and total hydrocarbons and 52% of sulphur recovery. The optimum HRT of aerobic moving bed reactor was observed as 16 h (total HRT of 64 h for anoxic and aerobic reactors) for complete removals of phenol, total hydrocarbons, COD (chemical oxygen demand) and ammonia-nitrogen with nitrification.

Less common applications of simulated moving bed chromatography in the pharmaceutical industry.

PubMed

Huthmann, E; Juza, M

2005-10-21

Simulated moving bed (SMB) chromatography is often perceived in the pharmaceutical industry as chromatographic method for separating binary mixtures, like racemates. However, SMB can also be used for unbalanced separations, i.e. binary mixtures of varying compositions and multi-component mixtures. These less common application modes of isocratic SMB chromatography are exemplified for four different compounds (racemates and diastereomers) and discussed in view of the so-called 'triangle theory' from an industrial perspective.

Model-based design of a pilot-scale simulated moving bed for purification of citric acid from fermentation broth.

PubMed

Wu, Jinglan; Peng, Qijun; Arlt, Wolfgang; Minceva, Mirjana

2009-12-11

One of the conventional processes used for the recovery of citric acid from its fermentation broth is environmentally harmful and cost intensive. In this work an innovative benign process, which comprises simulated moving bed (SMB) technology and use of a tailor-made tertiary poly(4-vinylpyridine) (PVP) resin as a stationary phase is proposed. This paper focuses on a model-based design of the operation conditions for an existing pilot-scale SMB plant. The SMB unit is modeled on the basis of experimentally determined hydrodynamics, thermodynamics and mass transfer characteristics in a single chromatographic column. Three mathematical models are applied and validated for the prediction of the experimentally attained breakthrough and elution profiles of citric acid and the main impurity component (glucose). The transport dispersive model was selected for the SMB simulation and design studies, since it gives a satisfactory prediction of the elution profiles within acceptable computational time. The equivalent true moving bed (TMB) and SMB models give a good prediction of the experimentally attained SMB separation performances, obtained with a real clarified and concentrated fermentation broth as a feed mixture. The SMB separation requirements are set to at least 99.8% citric acid purity and 90% citric acid recovery in the extract stream. The complete regeneration in sections 1 and 4 is unnecessary. Therefore the net flow rates in all four SMB sections have been considered in the unit design. The influences of the operating conditions (the flow rate in each section, switching time and unit configuration) on the SMB performances were investigated systematically. The resulting SMB design provides 99.8% citric acid purity and 97.2% citric acid recovery in the extract. In addition the citric acid concentration in the extract is a half of its concentration in the pretreated fermentation broth (feed).

Centrifugal air-assisted melt agglomeration for fast-release "granulet" design.

PubMed

Wong, Tin Wui; Musa, Nafisah

2012-07-01

Conventional melt pelletization and granulation processes produce round and dense, and irregularly shaped but porous agglomerates respectively. This study aimed to design centrifugal air-assisted melt agglomeration technology for manufacture of spherical and yet porous "granulets" for ease of downstream manufacturing and enhancing drug release. A bladeless agglomerator, which utilized shear-free air stream to mass the powder mixture of lactose filler, polyethylene glycol binder and poorly water-soluble tolbutamide drug into "granulets", was developed. The inclination angle and number of vane, air-impermeable surface area of air guide, processing temperature, binder content and molecular weight were investigated with reference to "granulet" size, shape, texture and drug release properties. Unlike fluid-bed melt agglomeration with vertical processing air flow, the air stream in the present technology moved centrifugally to roll the processing mass into spherical but porous "granulets" with a drug release propensity higher than physical powder mixture, unprocessed drug and dense pellets prepared using high shear mixer. The fast-release attribute of "granulets" was ascribed to porous matrix formed with a high level of polyethylene glycol as solubilizer. The agglomeration and drug release outcomes of centrifugal air-assisted technology are unmet by the existing high shear and fluid-bed melt agglomeration techniques. Copyright © 2012 Elsevier B.V. All rights reserved.

Statistical description of flume experiments on mixed-size bed-load transport and bed armoring processes

NASA Astrophysics Data System (ADS)

Chen, D.; Zhang, Y.

2008-12-01

The objective of this paper is to describe the statistical properties of experiments on non-uniform bed-load transport as well as the mechanism of bed armoring processes. Despite substantial effort made over the last two decades, the ability to compute the bed-load flux in a turbulent system remains poor. The major obstacles include the poor understanding of the formation of armor lays on bed surfaces. Such a layer is much flow-resistible than the underlying material and therefore significantly inhibits sediment transport from the reach. To study the problem, we conducted a flume study for mixed sand/gravel sediments. We observed that aggregated sediment blocks were the most common characters in armor layers - the largest sizes resist hydraulic forces, while the smaller sizes add interlocking support and prevent loss of fine material through gaps between the larger particles. Fractional transport rates with the existing of armor layers were measured with time by sediment trapping method at the end of flume. To address the intermittent and time-varying behavior of bed-load transport during bed armoring processes, we investigated the probability distribution of the fractional bed-load transport rates, and the underlying dynamic model derived from the continuous time random walk framework. Results indicate that it is critical to consider the impact of armor layers when a flow is sufficient to move some of the finer particles and yet insufficient to move all the larger particles on a channel bed.

Successional development of biofilms in moving bed biofilm reactor (MBBR) systems treating municipal wastewater.

PubMed

Biswas, Kristi; Taylor, Michael W; Turner, Susan J

2014-02-01

Biofilm-based technologies, such as moving bed biofilm reactor (MBBR) systems, are widely used to treat wastewater. Biofilm development is important for MBBR systems as much of the microbial biomass is retained within reactors as biofilm on suspended carriers. Little is known about this process of biofilm development and the microorganisms upon which MBBRs rely. We documented successional changes in microbial communities as biofilms established in two full-scale MBBR systems treating municipal wastewater over two seasons. 16S rRNA gene-targeted pyrosequencing and clone libraries were used to describe microbial communities. These data indicate a successional process that commences with the establishment of an aerobic community dominated by Gammaproteobacteria (up to 52 % of sequences). Over time, this community shifts towards dominance by putatively anaerobic organisms including Deltaproteobacteria and Clostridiales. Significant differences were observed between the two wastewater treatment plants (WWTPs), mostly due to a large number of sequences (up to 55 %) representing Epsilonproteobacteria (mostly Arcobacter) at one site. Archaea in young biofilms included several lineages of Euryarchaeota and Crenarchaeota. In contrast, the mature biofilm consisted entirely of Methanosarcinaceae (Euryarchaeota). This study provides new insights into the community structure of developing biofilms at full-scale WWTPs and provides the basis for optimizing MBBR start-up and operational parameters.

Flow-synchronous field motion refrigeration

DOEpatents

Hassen, Charles N.

2017-08-22

An improved method to manage the flow of heat in an active regenerator in a magnetocaloric or an electrocaloric heat-pump refrigeration system, in which heat exchange fluid moves synchronously with the motion of a magnetic or electric field. Only a portion of the length of the active regenerator bed is introduced to or removed from the field at one time, and the heat exchange fluid flows from the cold side toward the hot side while the magnetic or electric field moves along the active regenerator bed.

Rapid Cycle Amine (RCA 2.0) System Development

NASA Technical Reports Server (NTRS)

Papale, William; O'Coin, James; Wichowski, Robert; Chullen, Cinda; Campbell, Colin

2012-01-01

The Rapid Cycle Amine (RCA) system is a low power assembly capable of simultaneously removing carbon dioxide (CO2) and humidity from an influent air steam and subsequent regeneration when exposed to a vacuum source. Two solid amine sorbent beds are alternated between an uptake mode and a regeneration mode. During the uptake mode, the sorbent is exposed to an air steam (ventilation loop) to adsorb CO2 and water vapor, while during the regeneration mode, the sorbent rejects the adsorbed CO2 and water vapor to a vacuum source. The two beds operate such that while one bed is in the uptake mode, the other is in the regeneration mode, thus continuously providing an on-service sorbent bed by which CO2 and humidity may be removed. A novel valve assembly provides a simple means of diverting the process air flow through the uptake bed while simultaneously directing the vacuum source to the regeneration bed. Additionally, the valve assembly is designed to allow for switching between uptake and regeneration modes with only one moving part while minimizing gas volume losses to the vacuum source by means of an internal pressure equalization step during actuation. The process can be controlled by a compact, low power controller design with several modes of operation available to the user. Together with NASA, United Technologies Corporation Aerospace Systems has been developing RCA 2.0 based on performance and design feedback on several sorbent bed test articles and valve design concepts. A final design was selected in November 2011 and fabricated and assembled between March and August 2012, with delivery to NASA-JSC in September 2012. This paper will provide an overview on the RCA system design and results of pre-delivery testing.

Coupled large eddy simulation and discrete element model of bedload motion

NASA Astrophysics Data System (ADS)

Furbish, D.; Schmeeckle, M. W.

2011-12-01

We combine a three-dimensional large eddy simulation of turbulence to a three-dimensional discrete element model of turbulence. The large eddy simulation of the turbulent fluid is extended into the bed composed of non-moving particles by adding resistance terms to the Navier-Stokes equations in accordance with the Darcy-Forchheimer law. This allows the turbulent velocity and pressure fluctuations to penetrate the bed of discrete particles, and this addition of a porous zone results in turbulence structures above the bed that are similar to previous experimental and numerical results for hydraulically-rough beds. For example, we reproduce low-speed streaks that are less coherent than those over smooth-beds due to the episodic outflow of fluid from the bed. Local resistance terms are also added to the Navier-Stokes equations to account for the drag of individual moving particles. The interaction of the spherical particles utilizes a standard DEM soft-sphere Hertz model. We use only a simple drag model to calculate the fluid forces on the particles. The model reproduces an exponential distribution of bedload particle velocities that we have found experimentally using high-speed video of a flat bed of moving sand in a recirculating water flume. The exponential distribution of velocity results from the motion of many particles that are nearly constantly in contact with other bed particles and come to rest after short distances, in combination with a relatively few particles that are entrained further above the bed and have velocities approaching that of the fluid. Entrainment and motion "hot spots" are evident that are not perfectly correlated with the local, instantaneous fluid velocity. Zones of the bed that have recently experienced motion are more susceptible to motion because of the local configuration of particle contacts. The paradigm of a characteristic saltation hop length in riverine bedload transport has infused many aspects of geomorphic thought, including even bedrock erosion. In light of our theoretical, experimental, and numerical findings supporting the exponential distribution of bedload particle motion, the idea of a characteristic saltation hop should be scrapped or substantially modified.

New technological developments provide deep-sea sediment density flow insights: the Monterey Coordinated Canyon Experiment

NASA Astrophysics Data System (ADS)

O'Reilly, T. C.; Kieft, B.; Chaffey, M. R.; Wolfson-Schwehr, M.; Herlien, R.; Bird, L.; Klimov, D.; Paull, C. K.; Gwiazda, R.; Lundsten, E. M.; Anderson, K.; Caress, D. W.; Sumner, E. J.; Simmons, S.; Parsons, D. R.; Talling, P.; Rosenberger, K. J.; Xu, J.; Maier, K. L.; Gales, J. A.

2017-12-01

The Monterey Coordinated Canyon Experiment (CCE) deployed an array of instruments along the Monterey Canyon floor to characterize the structure, velocity and frequency of sediment flows. CCE utilized novel technologies developed at MBARI to capture sediment flow data in unprecedented detail. 1. The Seafloor Instrument Node (SIN) at 1850 meters depth housed 3 ADCPs at 3 different frequencies, CTD, current meter, oxygen optode, fluorometer/backscatter sensor, and logged data at 10 second intervals or faster. The SIN included an acoustic modem for communication with shore through a Wave Glider relay, and provided high-resolution measurements of three flow events during three successive deployments over 1.5 years. 2. Beachball-sized Benthic Event Detectors (BEDs) were deployed on or under the seafloor to measure the characteristics of sediment density flows. Each BED recorded data from a pressure sensor and a 3-axis accelerometer and gyro to characterize motions during transport events (e.g. tumble vs rotation). An acoustic modem capable of operating through more than a meter of sediment enabled communications with a ship or autonomous surface vehicle. Multiple BEDs were deployed at various depths in the canyon during CCE, detecting and measuring many transport events; one BED moved 9 km down canyon in 50 minutes during one event. 3. Wave Glider Hot Spot (HS), equipped with acoustic and RF modems, acted as data relay between SIN, BEDs and shore, and acoustically located BEDs after sediment density flows.. In some cases HS relayed BED motion data to shore within a few hours of the event. HS provided an acoustic console to the SIN, allowing shore-based users to check SIN health and status, perform maintenance, etc. 4. Mapping operations were conducted 4 times at the SIN site to quantify depositional and erosional patterns, utilizing a prototype ultra-high-resolution mapping system on the ROV Doc Ricketts. The system consists of a 400-kHz Reson 7125 multibeam sonar, a 3DatDepth SL1 subsea LiIDAR, two stereo color cameras, and a Kearfott SeaDevil INS. At a survey altitude of 3 m above the bed, the mapping system provides 5-cm resolution multibeam bathymetry, 1-cm resolution lidar bathymetry, and 2-mm resolution photomosaics. We will describe the design and full capabilities of these novel systems.

Controlled biomass formation and kinetics of toluene degradation in a bioscrubber and in a reactor with a periodically moved trickle-bed.

PubMed

Wübker, S M; Laurenzis, A; Werner, U; Friedrich, C

1997-08-20

The kinetics of degradation of toluene from a model waste gas and of biomass formation were examined in a bioscrubber operated under different nutrient limitations with a mixed culture. The applicability of the kinetics of continuous cultivation of the mixed culture was examined for a special trickle-bed reactor with a periodically moved filter bed. The efficiency of toluene elimination of the bioscrubber was 50 to 57% and depended on the toluene mass transfer as evident from a constant productivity of 0.026 g dry cell weight/L . h over the dilution rate. Under potassium limitation the biomass productivity was reduced by 60% to 0.011 g dry cell weight/L . h at a dilution rate of 0.013/h. Conversely, at low dilution rates the specific toluene degradation rates increased. Excess biomass in a trickle-bed reactor causes reduction of interfacial area and mass transfer, and increase in pressure drop. To avoid these disadvantages, the trickle-bed was moved periodically and biomass was removed with outflowing medium. The concentration of steady state biomass fixed on polyamide beads decreased hyperbolically with the dilution rate. Also, the efficiency of toluene degradation decreased from 72 to 56% with increasing dilution rate while the productivity increased. Potassium limitation generally caused a reduction in biomass, productivity, and yield while the specific degradation increased with dilution rate. This allowed the application of the principles of the chemostat to the trickle-bed reactor described here, for toluene degradation from waste gases. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 686-692, 1997.

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

Marrocco, M.

The Ohio Power Company`s Tidd Pressurized Fluidized Bed Combined Cycle (PFBC) program continues to be the only operating PFBC demonstration program in the nation. The 70 MWe Tidd Demonstration Plant is a Round 1 Clean Coal Technology Project constructed to demonstrate the viability of PFBC combined cycle technology. The plant is now in Rs fourth year of operation. The technology has clearly demonstrated Rs ability to achieve sulfur capture of greater than 95%. The calcium to sulfur molar ratios have been demonstrated to exceed original projections. Unit availability has steadily increased and has been demonstrated to be competitive with othermore » technologies. The operating experience of the first forty-four months of testing has moved the PFBC process from a {open_quotes}promising technology{close_quotes} to available, proven option for efficient, environmentally acceptable base load generation. Funding for the $210 million program is provided by Ohio Power Company, The U.S. Department of Energy, The Ohio Coal Development Office, and the PFBC process vendors - Asea Brown Boveri Carbon (ABBC) and Babcock and Wilcox (B&W).« less

Capture of a recombinant protein from unclarified canola extract using streamline expanded bed anion exchange.

PubMed

Bai, Yun; Glatz, Charles E

2003-03-30

The feasibility of applying expanded bed adsorption technology to recombinant protein recovery from extracts of transgenic canola (rapeseed) was assessed. The extraction step results in a suspension of high solids content that is difficult to clarify. The coarse portion of the solids can be removed easily, and our aim was to operate the expanded bed in the presence of the recalcitrant particulates. Recombinant beta-glucuronidase (rGUS) produced in transgenic canola seed was the model system. Diethylaminoethyl (DEAE) and Streamline DEAE resin exhibited similar binding and elution properties for both rGUS and native canola proteins. More than 95% of native canola proteins did not bind to DEAE resins at pH 7.5, whereas the bound proteins were fractionated by two-step salt elution into two groups with the first peak, containing 70% of total bound proteins, at 20 mS/cm, followed by elution of rGUS at 50 mS/cm. The adsorption isotherm was only slightly influenced by the presence of up to 14 mg solids/mL extract; C(m) and K(d) changed by -1% and +39%, respectively. Bed expansion was semiquantitatively predictable from physical properties of the fluid together with Stokes's law and the Richardson-Zaki correlation for both clarified and partially clarified extracts. The presence of 1.4% solids did not change rGUS breakthrough behavior of the expanded bed; however, a small difference between expanded bed and packed bed was observed early in the sample loading stage, during which bed expansion adjusts. Canola solids moved through the column in approximately plug flow with no detriment to bed stability. Seventy-two percent recovery of 34-fold purified rGUS was obtained after initial loading of 1.4% (w/w) solids extract to 25% breakthrough. Copyright 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 855-864, 2003.

Real-time imaging as an emerging process analytical technology tool for monitoring of fluid bed coating process.

PubMed

Naidu, Venkata Ramana; Deshpande, Rucha S; Syed, Moinuddin R; Wakte, Pravin S

2018-07-01

A direct imaging system (Eyecon TM ) was used as a Process Analytical Technology (PAT) tool to monitor fluid bed coating process. Eyecon TM generated real-time onscreen images, particle size and shape information of two identically manufactured laboratory-scale batches. Eyecon TM has accuracy of measuring the particle size increase of ±1 μm on particles in the size range of 50-3000 μm. Eyecon TM captured data every 2 s during the entire process. The moving average of D90 particle size values recorded by Eyecon TM were calculated for every 30 min to calculate the radial coating thickness of coated particles. After the completion of coating process, the radial coating thickness was found to be 11.3 and 9.11 μm, with a standard deviation of ±0.68 and 1.8 μm for Batch 1 and Batch 2, respectively. The coating thickness was also correlated with percent weight build-up by gel permeation chromatography (GPC) and dissolution. GPC indicated weight build-up of 10.6% and 9.27% for Batch 1 and Batch 2, respectively. In conclusion, weight build-up of 10% can also be correlated with 10 ± 2 μm increase in the coating thickness of pellets, indicating the potential applicability of real-time imaging as an endpoint determination tool for fluid bed coating process.

Ergonomic evaluation of slide boards used by home care aides to assist client transfers.

PubMed

Sun, Chuan; Buchholz, Bryan; Quinn, Margaret; Punnett, Laura; Galligan, Catherine; Gore, Rebecca

2018-07-01

Home care aides risk musculoskeletal injury because they lift and move clients; the body weight of most adults exceeds the NIOSH recommended limit for lifting. Methods to reduce manual patient lifting in institutional settings are often technically or economically infeasible in home care. Our goal was to identify suitable, safe, low-technology transfer devices for home care use. Sixteen experienced home care aides performed client transfers from wheelchair to bed (upward) and bed to wheelchair (downward) in a simulated home care environment (laboratory), using four different slide boards and by hand without a device. Aides' hand forces were measured during client transfers; aides also evaluated usability of each board. Hand forces exerted while using slide boards were mostly lower than in manual transfer, and forces were lower in downward versus upward transfers. Aides judged a board with a sliding mechanism easier to use than boards without a sliding mechanism. Practitioner Summary: This paper provides quantitative biomechanical measurements showing that slide boards reduced the hand forces needed by home care aides to transfer clients from bed to wheel chair and vice versa, compared to manual lifting. Using a semi-quantitative usability survey, aides identified boards with a sliding mechanism easiest to use.

Avalanche photo diodes in the observatory environment: lucky imaging at 1-2.5 microns

NASA Astrophysics Data System (ADS)

Vaccarella, A.; Sharp, R.; Ellis, M.; Singh, S.; Bloxham, G.; Bouchez, A.; Conan, R.; Boz, R.; Bundy, D.; Davies, J.; Espeland, B.; Hart, J.; Herrald, N.; Ireland, M.; Jacoby, G.; Nielsen, J.; Vest, C.; Young, P.; Fordham, B.; Zovaro, A.

2016-08-01

The recent availability of large format near-infrared detectors with sub-election readout noise is revolutionizing our approach to wavefront sensing for adaptive optics. However, as with all near-infrared detector technologies, challenges exist in moving from the comfort of the laboratory test-bench into the harsh reality of the observatory environment. As part of the broader adaptive optics program for the GMT, we are developing a near-infrared Lucky Imaging camera for operational deployment at the ANU 2.3 m telescope at Siding Spring Observatory. The system provides an ideal test-bed for the rapidly evolving Selex/SAPHIRA eAPD technology while providing scientific imaging at angular resolution rivalling the Hubble Space Telescope at wavelengths λ = 1.3-2.5 μm.

Orifice plate for controlling solids flow, methods of use thereof and articles comprising the same

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

Jukkola, Glen D.; Teigen, Bard C.

Disclosed herein is an orifice plate comprising one or more plates having orifices disposed therein; the orifices being operative to permit the flow of solids from a moving bed heat exchanger to a solids flow control system; where the orifice plate is downstream of a tube bundle of the moving bed heat exchanger and upstream of the solids flow control system and wherein the orifice plate is operative to evenly distribute the flow of solids in the solids flow control system.

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

Nixon, J.D., E-mail: j.nixon@kingston.ac.uk; Wright, D.G.; Dey, P.K.

Highlights: • We evaluate operational municipal solid waste incinerators in the UK. • The supply chain of four case study plants are examined and compared in detail. • Technical, financial and operational data has been gathered for the four plants. • We suggest the best business practices for waste incinerators. • Appropriate strategy choices are the major difficulties for waste to energy plants. - Abstract: The uptake in Europe of Energy from Waste (EfW) incinerator plants has increased rapidly in recent years. In the UK, 25 municipal waste incinerators with energy recovery are now in operation; however, their waste supplymore » chains and business practices vary significantly. With over a hundred more plant developments being considered it is important to establish best business practices for ensuring efficient environmental and operational performance. By reviewing the 25 plants we identify four suitable case study plants to compare technologies (moving grate, fluidised bed and rotary kiln), plant economics and operations. Using data collected from annual reports and through interviews and site visits we provide recommendations for improving the supply chain for waste incinerators and highlight the current issues and challenges faced by the industry. We find that plants using moving grate have a high availability of 87–92%. However, compared to the fluidised bed and rotary kiln, quantities of bottom ash and emissions of hydrogen chloride and carbon monoxide are high. The uptake of integrated recycling practices, combined heat and power, and post incineration non-ferrous metal collections needs to be increased among EfW incinerators in the UK. We conclude that one of the major difficulties encountered by waste facilities is the appropriate selection of technology, capacity, site, waste suppliers and heat consumers. This study will be of particular value to EfW plant developers, government authorities and researchers working within the sector of waste management.« less

Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River

USGS Publications Warehouse

Gartner, J.W.; Ganju, N.K.

2007-01-01

Discharge measurements were made by acoustic Doppler current profiler at two locations on the Colorado River during the 2004 controlled flood from Glen Canyon Dam, Arizona. Measurement hardware and software have constantly improved from the 1980s such that discharge measurements by acoustic profiling instruments are now routinely made over a wide range of hydrologic conditions. However, measurements made with instruments deployed from moving boats require reliable boat velocity data for accurate measurements of discharge. This is normally accomplished by using special acoustic bottom track pings that sense instrument motion over bottom. While this method is suitable for most conditions, high current flows that produce downstream bed sediment movement create a condition known as moving bed that will bias velocities and discharge to lower than actual values. When this situation exists, one solution is to determine boat velocity with satellite positioning information. Another solution is to use a lower frequency instrument. Discharge measurements made during the 2004 Glen Canyon controlled flood were subject to moving-bed conditions and frequent loss of bottom track. Due to site conditions and equipment availability, the measurements were conducted without benefit of external positioning information or lower frequency instruments. This paper documents and evaluates several techniques used to correct the resulting underestimated discharge measurements. One technique produces discharge values in good agreement with estimates from numerical model and measured hydrographs during the flood. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

Additive Manufacturing of Advanced High Temperature Masking Fixtures for EBPVD TBC Coating

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

List, III, Frederick Alyious; Feuerstein, Albert; Dehoff, Ryan

2016-03-30

The purpose of this Manufacturing Demonstration Facility (MDF) technical collaboration project between Praxair Surface Technologies, Inc. (PST) and Oak Ridge National Laboratory (ORNL) was to develop an additive manufacturing process to fabricate next generation high temperature masking fixtures for coating of turbine airfoils with ceramic Thermal Barrier Coatings (TBC) by the Electron Beam Physical Vapor Deposition (EBPVD) process. Typical masking fixtures are sophisticated designs and require complex part manipulation in order to achieve the desired coating distribution. Fixtures are typically fabricated from high temperature nickel (Ni) based superalloys. The fixtures are fabricated from conventional processes by welding of thin sheetmore » material into a complex geometry, to decrease the weight load for the manipulator and to reduce the thermal mass of the fixture. Recent attempts have been made in order to fabricate the fixtures through casting, but thin walled sections are difficult to cast and have high scrap rates. This project focused on understanding the potential for fabricating high temperature Ni based superalloy fixtures through additive manufacturing. Two different deposition processes; electron beam melting (EBM) and laser powder bed fusion were evaluated to determine the ideal processing route of these materials. Two different high temperature materials were evaluated. The high temperature materials evaluated were Inconel 718 and another Ni base alloy, designated throughout the remainder of this document as Alloy X, as the alloy composition is sensitive. Inconel 718 is a more widely utilized material for additive manufacturing although it is not currently the material utilized for current fixtures. Alloy X is the alloy currently used for the fixtures, but is not a commercially available alloy for additive manufacturing. Praxair determined it was possible to build the fixture using laser powder bed technology from Inconel 718. ORNL fabricated the fixture geometry using the EBM technology in order to compare deposition features such as surface roughness, geometric accuracy, deposition rate, surface and subsurface porosity, and material quality. It was determined that the laser powder bed technology was ideal for the geometry and requirements of the fixture set by Praxair, and Praxair moved forward with the purchase of a laser powder bed system. The subsequent portion of the project focused on determining the ideal processing parameters for alloy X for the laser powder bed system using ORNL’s Renishaw laser powder bed system. Praxair supplied gas atomized powders of alloy X material with properties specified by ORNL. ORNL printed text cube arrays in order to determine the ideal combination of laser powder and laser travel speed in order to maximize material density, improve surface quality, and maintain geometric accuracy. Additional powder supplied by Praxair was used to fabricate a full-scale fixture component.« less

The Safety of Hospital Beds

PubMed Central

Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K.; Bloswick, Donald

2015-01-01

To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients’ ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients’ use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated. PMID:28462302

Waste tyre pyrolysis: modelling of a moving bed reactor.

PubMed

Aylón, E; Fernández-Colino, A; Murillo, R; Grasa, G; Navarro, M V; García, T; Mastral, A M

2010-12-01

This paper describes the development of a new model for waste tyre pyrolysis in a moving bed reactor. This model comprises three different sub-models: a kinetic sub-model that predicts solid conversion in terms of reaction time and temperature, a heat transfer sub-model that calculates the temperature profile inside the particle and the energy flux from the surroundings to the tyre particles and, finally, a hydrodynamic model that predicts the solid flow pattern inside the reactor. These three sub-models have been integrated in order to develop a comprehensive reactor model. Experimental results were obtained in a continuous moving bed reactor and used to validate model predictions, with good approximation achieved between the experimental and simulated results. In addition, a parametric study of the model was carried out, which showed that tyre particle heating is clearly faster than average particle residence time inside the reactor. Therefore, this fast particle heating together with fast reaction kinetics enables total solid conversion to be achieved in this system in accordance with the predictive model. Copyright © 2010 Elsevier Ltd. All rights reserved.

Behavior of nitrogen removal in an aerobic sponge based moving bed biofilm reactor.

PubMed

Zhang, Xinbo; Song, Zi; Guo, Wenshan; Lu, Yanmin; Qi, Li; Wen, Haitao; Ngo, Huu Hao

2017-12-01

This study aims to investigate the behavior of nitrogen removal in an aerobic sponge based moving bed biofilm reactor by evaluating nitrification and denitrification rates of sponge biocarriers from three aerobic moving bed biofilm reactors (MBBRs) with filling ratios of 10% (R-10), 20% (R-20) and 30% (R-30). Results showed that the highest removal efficiencies of total nitrogen in three reactors were 84.5% (R-10), 93.6% (R-20) and 95.3% (R-30). Correspondingly, simultaneous nitrification and denitrification rate (SND) was 90.9%, 97.6% and 100%, respectively. Although R-20 had the highest attached-growth biomass (AGB) per gram of sponge compared to the other two reactors, R-30 showed the maximum ammonium oxidation rate (AOR) (2.1826±0.0717mgNH 4 + -N/gAGB/h) and denitrification rate (DNR) (5.0852±0.0891mgNO 3 - -N/gAGB/h), followed by R-20 and R-10. These results indicated AOR, DNR and AGB were affected by the filling ratio under the same operation mode. Copyright © 2017 Elsevier Ltd. All rights reserved.

High quality fuel gas from biomass pyrolysis with calcium oxide.

PubMed

Zhao, Baofeng; Zhang, Xiaodong; Chen, Lei; Sun, Laizhi; Si, Hongyu; Chen, Guanyi

2014-03-01

The removal of CO2 and tar in fuel gas produced by biomass thermal conversion has aroused more attention due to their adverse effects on the subsequent fuel gas application. High quality fuel gas production from sawdust pyrolysis with CaO was studied in this paper. The results of pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments indicate that the mass ratio of CaO to sawdust (Ca/S) remarkably affects the behavior of sawdust pyrolysis. On the basis of Py-GC/MS results, one system of a moving bed pyrolyzer coupled with a fluid bed combustor has been developed to produce high quality fuel gas. The lower heating value (LHV) of the fuel gas was above 16MJ/Nm(3) and the content of tar was under 50mg/Nm(3), which is suitable for gas turbine application to generate electricity and heat. Therefore, this technology may be a promising route to achieve high quality fuel gas for biomass utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

Spatially distributed fiber sensor with dual processed outputs

NASA Astrophysics Data System (ADS)

Xu, X.; Spillman, William B., Jr.; Claus, Richard O.; Meissner, K. E.; Chen, K.

2005-05-01

Given the rapid aging of the world"s population, improvements in technology for automation of patient care and documentation are badly needed. We have previously demonstrated a 'smart bed' that can non-intrusively monitor a patient in bed and determine a patient's respiration, heart rate and movement without intrusive or restrictive medical measurements. This is an application of spatially distributed integrating fiber optic sensors. The basic concept is that any patient movement that also moves an optical fiber within a specified area will produce a change in the optical signal. Two modal modulation approaches were considered, a statistical mode (STM) sensor and a high order mode excitation (HOME) sensor. The present design includes an STM sensor combined with a HOME sensor, using both modal modulation approaches. A special lens system allows only the high order modes of the optical fiber to be excited and coupled into the sensor. For handling output from the dual STM-HOME sensor, computer processing methods are discussed that offer comprehensive perturbation analysis for more reliable patient monitoring.

Combined fluidized bed retort and combustor

DOEpatents

Shang, Jer-Yu; Notestein, John E.; Mei, Joseph S.; Zeng, Li-Wen

1984-01-01

The present invention is directed to a combined fluidized bed retorting and combustion system particularly useful for extracting energy values from oil shale. The oil-shale retort and combustor are disposed side-by-side and in registry with one another through passageways in a partition therebetween. The passageways in the partition are submerged below the top of the respective fluid beds to preclude admixing or the product gases from the two chambers. The solid oil shale or bed material is transported through the chambers by inclining or slanting the fluidizing medium distributor so that the solid bed material, when fluidized, moves in the direction of the downward slope of the distributor.

Being a Nursing Aide; Student Manual.

ERIC Educational Resources Information Center

American Hospital Association, Chicago, IL.

Developed for students receiving on-the-job training as nursing aides, this illustrated manual contains these chapters: (1) Orientation, (2) Introduction to the Patient, (3) Your Working Environment, (4) The Patient's Unit: Making the Unoccupied Bed, (5) Lifting, Moving, and Transporting Patients: Making the Occupied Bed, (6) Personal Care of the…

Effects of acuity-adaptable rooms on flow of patients and delivery of care.

PubMed

Hendrich, Ann L; Fay, Joy; Sorrells, Amy K

2004-01-01

Delayed transfers of patients between nursing units and lack of available beds are significant problems that increase costs and decrease quality of care and satisfaction among patients and staff. To test whether use of acuity-adaptable rooms helps solve problems with transfers of patients, satisfaction levels, and medical errors. A pre-post method was used to compare the effects of environmental design on various clinical and financial measures. Twelve outcome-based questions were formulated as the basis for inquiry. Two years of baseline data were collected before the unit moved and were compared with 3 years of data collected after the move. Significant improvements in quality and operational cost occurred after the move, including a large reduction in clinician handoffs and transfers; reductions in medication error and patient fall indexes; improvements in predictive indicators of patients' satisfaction; decrease in budgeted nursing hours per patient day and increased available nursing time for direct care without added cost; increase in patient days per bed, with a smaller bed base (number of beds per patient days). Some staff turnover occurred during the first year; turnover stabilized thereafter. Data in 5 key areas (flow of patients and hospital capacity, patients' dissatisfaction, sentinel events, mean length of stay, and allocation of nursing productivity) appear to be sufficient to test the business case for future investment in partial or complete replication of this model with appropriate populations of patients.

EMERGING TECHNOLOGY BULLETIN: SPOUTED BED REACTOR

EPA Science Inventory

The Spouted Bed Reactor (SBR) technology utilizes the unique attributes of the "spouting " fluidization regime, which can provide heat transfer rates comparable to traditional fluid beds, while providing robust circulation of highly heterogeneous solids, concurrent with very agg...

Measuring bed load discharge in rivers: bedload-surrogate monitoring workshop Minneapolis, Minnesota, 11-14 April 2007

USGS Publications Warehouse

Gray, John R.; Laronne, Jonathan B.; Marr, Jeffrey D.G.

2007-01-01

The International Bedload-Surrogate Monitoring Workshop (http://www.nced.umn.edu/BRIC_2007.html), organized by the Bedload Research International Cooperative (BRIC; www.bedloadresearch.org), was held to assess and abet progress in continuous, semiautomated, or fully automated (surrogate) technologies for monitoring bed load discharge in gravel-, sand-, and mixed gravel-sand-bedded rivers. Direct bed load measurements, particularly at medium and high flows, during which most bed load occurs, tend to be time-consuming, expensive, and potentially hazardous. Surrogate technologies developed largely over the past decade and used at a number of research sites around the world show considerable promise toward providing relatively dense, robust, and quantifiably reliable bed load data sets. However, information on the efficacy of selected technologies for use in monitoring programs is needed, as is identification of the ways and means for bringing the most promising and practical of the technologies to fruition.

Supply-Limited Bedforms in a Gravel-Sand Transition

NASA Astrophysics Data System (ADS)

Venditti, J. G.; Nittrouer, J. A.; Humphries, R. P.; Allison, M. A.

2009-12-01

Rivers often exhibit an abrupt transition from gravel to sand-bedded conditions as river channel slopes decrease. A distinct suite of bedforms has been observed through these reaches where sand supply to the bed is limited. The suite of bedforms includes a sequence of sand ribbons, barchans, and channel spanning dunes as sediment supply increases in the downstream direction. While these bedforms have been extensively documented in laboratory channels, there are relatively few observations of this sequence of supply-limited bedforms from large natural channels. Here we examine the sequence through the gravel-sand transition of the Fraser River in Southwestern British Columbia. We mapped the bed using multi-beam swath-bathymetry (Reson 8101 Seabat) at high flow (~9,000 m3s-1) immediately following a high peak flow of 11,800 m3s-1 in June 2007 The bed material grades from >70% gravel to entirely sand through the reach. The bedforms follow the expected sequence where sand ribbons and barchanoid forms cover the bed where it is primarily gravel. Channel spanning dunes form as the sand bed coverage increases. Bedform dimensions (height and length) increase moving downstream as the sand moving on the bed increases. Supply-unlimited bedforms typically scale with the flow depth where the height is 1/5 the flow depth. The bedforms developed over the gravel are undersized by this criterion. Downstream, where the bed is dominantly sand, bedforms do scale with flow depth. These data highlight the dominant role sediment supply can play in bedform morphology and scaling, confirming patterns observed in laboratory data.

Granular controls on the dispersion of bed load tracers

NASA Astrophysics Data System (ADS)

Jerolmack, D. J.; Martin, R. L.; Phillips, C. B.

2014-12-01

Coarse particles are transported in a river as bed load, i.e., they move in frequent contact with and are supported by the granular bed. This movement is typically intermittent and may be described by a series of steps are rests, the distributions of which determine particle dispersion. Laboratory and field studies of bed load tracer dispersion have reported sub- and super-diffusive behavior, both of which have been successfully reproduced with stochastic transport models. Although researchers have invoked heavy-tailed step lengths as the cause of anomalous dispersion, most observations report thin-tailed distributions. Little attention has been paid to rest periods, and stochastic transport models have not been connected to the underlying mechanics of particle motion. Based on theoretical and experimental evidence, we argue that step lengths are thin-tailed and do not control the longterm dispersion of bed load tracers; they are determined by momentum balance between the fluid and solid. Using laboratory experiments with both marbles and natural sediments, we demonstrate that the rest time distribution is power law, and argue that this distribution controls asymptotic dispersion. Observed rest times far exceed any hydrodynamic timescale. Experiments reveal that rest times of deposited particles are governed by fluctuations in river bed elevation; in particular, the return time for the bed to scour to the base of a deposited particle. Stochastic fluctuations in bed elevation are describable by an Ornstein-Uhlenbeck (mean-reverting random walk) model that contains two parameters, which we show are directly related to the granular shear rate and range of bed elevation fluctuations, respectively. Combining these results with the theory of asymmetric random walks (particles only move downstream), we predict superdiffusive behavior that is in quantitative agreement with our observations of tracer dispersion in a natural river.

Questing activity in bed bug populations: male and female responses to host signals.

PubMed

Aak, Anders; Rukke, Bjørn A; Soleng, Arnulf; Rosnes, Marte K

2014-09-01

A large-arena bioassay is used to examine sex differences in spatiotemporal patterns of bed bug Cimex lectularius L. behavioural responses to either a human host or CO 2 gas. After release in the centre of the arena, 90% of newly-fed bed bugs move to hiding places in the corners within 24 h. They require 3 days to settle down completely in the arena, with generally low activity levels and the absence of responses to human stimuli for 5 days. After 8-9 days, persistent responses can be recorded. Sex differences are observed, in which females are more active during establishment, respond faster after feeding, expose themselves more than males during the daytime, and respond more strongly to the host signal. The number of bed bugs that rest in harbourages is found to vary significantly according to light setting and sex. Both sexes stay inside harbourages more in daylight compared with night, and males hide more than females during the daytime but not during the night. The spatial distribution of the bed bugs is also found to change with the presence of CO 2 , and peak aggregation around the odour source is observed after 24 min. Both male and female bed bugs move from hiding places or the border of the arena toward the centre where CO 2 is released. Peak responses are always highest during the night. Bed bug behaviour and behaviour-regulating features are discussed in the context of control methods.

Questing activity in bed bug populations: male and female responses to host signals

PubMed Central

Aak, Anders; Rukke, Bjørn A; Soleng, Arnulf; Rosnes, Marte K

2014-01-01

A large-arena bioassay is used to examine sex differences in spatiotemporal patterns of bed bug Cimex lectularius L. behavioural responses to either a human host or CO2 gas. After release in the centre of the arena, 90% of newly-fed bed bugs move to hiding places in the corners within 24 h. They require 3 days to settle down completely in the arena, with generally low activity levels and the absence of responses to human stimuli for 5 days. After 8–9 days, persistent responses can be recorded. Sex differences are observed, in which females are more active during establishment, respond faster after feeding, expose themselves more than males during the daytime, and respond more strongly to the host signal. The number of bed bugs that rest in harbourages is found to vary significantly according to light setting and sex. Both sexes stay inside harbourages more in daylight compared with night, and males hide more than females during the daytime but not during the night. The spatial distribution of the bed bugs is also found to change with the presence of CO2, and peak aggregation around the odour source is observed after 24 min. Both male and female bed bugs move from hiding places or the border of the arena toward the centre where CO2 is released. Peak responses are always highest during the night. Bed bug behaviour and behaviour-regulating features are discussed in the context of control methods. PMID:26166936

Increasing the capacity for treatment of chemical plant wastewater by replacing existing suspended carrier media with Kaldnes Moving Bed media at a plant in Singapore.

PubMed

Wessman, F G; Yan Yuegen, E; Zheng, Q; He, G; Welander, T; Rusten, B

2004-01-01

The Kaldnes biomedia K1, which is used in the patented Kaldnes Moving Bed biofilm process, has been tested along with other types of biofilm carriers for biological pretreatment of a complex chemical industry wastewater. The main objective of the test was to find a biofilm carrier that could replace the existing suspended carrier media and at the same time increase the capacity of the existing roughing filter-activated sludge plant by 20% or more. At volumetric organic loads of 7.1 kg COD/m3/d the Kaldnes Moving Bed process achieved much higher removal rates and much lower effluent concentrations than roughing filters using other carriers. The Kaldnes roughing stage achieved more than 85% removal of organic carbon and more than 90% removal of BOD5 at the tested organic load, which was equivalent to a specific biofilm surface area load of 24 g COD/m2/d. Even for the combined roughing filter-activated sludge process, the Kaldnes carriers outperformed the other carriers, with 98% removal of organic carbon and 99.6% removal of BOD5. The Kaldnes train final effluent concentrations were only 22 mg FOC/L and 7 mg BOD5/L. Based on the successful pilot testing, the full-scale plant was upgraded with Kaldnes Moving Bed roughing filters. During normal operation the upgraded plant has easily met the discharge limits of 100 mg COD/L and 50 mg SS/L. For the month of September 2002, with organic loads between 100 and 115% of the design load for the second half of the month, average effluent concentrations were as low as 9 mg FOC/L, 51 mg COD/L and 12 mg SS/L.

Salmon Spawning Effects on Streambed Stability

NASA Astrophysics Data System (ADS)

Buxton, T. H.; Buffington, J. M.; Yager, E.; Fremier, A. K.; Hassan, M. A.

2014-12-01

Female salmon build nests ("redds") in streambeds to protect their eggs from predation and damage by bed scour. During spawning, streambed material is mixed, fine sediment is winnowed downstream, and sediment is moved into a tailspill mound resembling the shape of a dune. Redd surfaces are coarser and better sorted than unspawned beds, which is thought to increase redd stability because larger grains are heavier and harder to move and sorting leads to higher friction angles for grain mobility. However, spawning also loosens sediment and creates topography that accelerates flow, both of which may increase particle mobility. We address factors controlling the relative stability of redds and unspawned beds using simulated salmon redds and water worked ("unspawned") beds composed of mixed-grain surfaces in a laboratory flume. Results show that simulated spawning lowered packing resistance to particle mobility on redds by an average of 32-39% compared to unspawned beds. Reductions in packing were sufficient to counter the higher inherent stability of relatively coarse, well sorted grains on redds, overall reducing critical shear stress by 8-20% relative to unspawned beds. In addition, boundary shear stress was 13-41% higher on redds due to flow convergence over the tailspill structure. Finally, redd instability relative to unspawned beds was observed in visual measurements of grain mobility, where bed-averaged shear stress was 22% lower at incipient motion and 29% lower at the discharge that mobilized all grain sizes on redds. Results of these complementary observations, along with sediment mass transport rates being nearly five times higher on a redd than an unspawned bed, indicate that redds are unstable compared to unspawned beds. Given these findings, further research is needed to investigate linkages between spawning disturbance and streambed mobility that may affect salmon reproduction in streams, and to assess whether a certain level of bed disturbance from spawning is required to restore ecosystem functions in streams with threatened populations of salmon.

Packed bed reactor for photochemical .sup.196 Hg isotope separation

DOEpatents

Grossman, Mark W.; Speer, Richard

1992-01-01

Straight tubes and randomly oriented pieces of tubing having been employed in a photochemical mercury enrichment reactor and have been found to improve the enrichment factor (E) and utilization (U) compared to a non-packed reactor. One preferred embodiment of this system uses a moving bed (via gravity) for random packing.

Hydrogen production from coal

NASA Technical Reports Server (NTRS)

1975-01-01

The gasification reactions necessary for the production of hydrogen from montana subbituminous coal are presented. The coal composition is given. The gasifier types mentioned include: suspension (entrained) combustion; fluidized bed; and moving bed. Each gasification process is described. The steam-iron process, raw and product gas compositions, gasifier feed quantities, and process efficiency evaluations are also included.

Lagrangian and Eulerian description of bed-load particle kinematics

NASA Astrophysics Data System (ADS)

Ballio, Francesco; Sadabadi, Seyed Abbas Hosseini; Pokrajac, Dubravka; Radice, Alessio

2016-04-01

The motion of bed-load sediment particles transported by a flow can be analyzed within a Lagrangian or an Eulerian framework. In the former case, we consider the particles as individual objects in motion and we study their kinematic properties. The latter approach is instead referred to suitably chosen control volumes. Quantities describing sediment motion in the two frameworks are different, and the relationships among the two approaches are not straightforward. In this work, we intend to discuss the kinematic properties of sediment transport: first, a set of quantities is univocally defined; then, relationships among different representations are explored. Proof-of-concept results presented in the study are from a recent experiment involving weak bed-load sediment transport, where the moving particles were released over a fixed rough bed. The bulk flow velocity was 1.4 times the critical value for incipient particle motion, and particles were mostly moving by rolling and sliding, with limited saltation. The particle motion was filmed from the top and the measurements were conducted by image-based methods, obtaining extensive samples of virtually-instantaneous quantities.

System design study to reduce capital and operating cost of a moving distributor, AFB advanced concept - comparison with an oil-fired boiler. Final report

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

Mah, C.S.; West, L.K.; Anderson, R.E.

1985-12-01

The Aerojet Energy Conversion Company, under contract with the United States Department of Energy, has performed a comparative economic study of the Aerojet Universal Atmospheric Fluidized Bed Combustion (UAFBC) system and a coventional atmospheric fluidized bed combustion (AFBC) system. The program title, ''System Design Study to Reduce Capital and Operating Cost and Bench Scale Testing of a Moving Distributor, AFB Concept,'' is a good description of the general objective of the program. The specific objective was to compare the UAFBC with the conventional AFBC in terms of normalized steam cost. The boilers were designed for 150,00 lb/hr of steam atmore » 650 psig and 750/sup 0/F. The reference coal used in the analysis was Pittsburgh No. 8 coal with a sulfur content of 4.3% and a higher heating value of 12,919 Bru/lb. The analysis assumed a plant life of 20 years and a discount rate of 15%. The UAFBC systems included the usual elements of the conventional cola-fired AFBC steam plant, but the coal preparation sysbsystem for the UAFBC was considerably simpler because the system can use ''run-of-mine'' coal. The UAFBC boiler itself consisted of a staged-combustion fluidized-bed, superimposed over a static bed, the latter supported by a moving distributor. It incorporated a fines burnup combustor, an entrained reciculating gas cleanup bed, and conventional convection boiler. The key features of the UAFBC design were: High fuel flexibility; low NO/sub x/ emission; and superior turndown capability. 30 refs., 52 figs., 12 tabs.« less

Modeling integrated fixed-film activated sludge and moving-bed biofilm reactor systems II: evaluation.

PubMed

Boltz, Joshua P; Johnson, Bruce R; Daigger, Glen T; Sandino, Julian; Elenter, Deborah

2009-06-01

A steady-state model presented by Boltz, Johnson, Daigger, and Sandino (2009) describing integrated fixed-film activated sludge (IFAS) and moving-bed biofilm reactor (MBBR) systems has been demonstrated to simulate, with reasonable accuracy, four wastewater treatment configurations with published operational data. Conditions simulated include combined carbon oxidation and nitrification (both IFAS and MBBR), tertiary nitrification MBBR, and post denitrification IFAS with methanol addition as the external carbon source. Simulation results illustrate that the IFAS/MBBR model is sufficiently accurate for describing ammonia-nitrogen reduction, nitrate/nitrite-nitrogen reduction and production, biofilm and suspended biomass distribution, and sludge production.

Down-flow moving-bed gasifier with catalyst recycle

DOEpatents

Halow, John S.

1999-01-01

The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction.

Staged fluidized-bed combustion and filter system

DOEpatents

Mei, Joseph S.; Halow, John S.

1994-01-01

A staged fluidized-bed combustion and filter system for substantially reducing the quantity of waste through the complete combustion into ash-type solids and gaseous products. The device has two fluidized-bed portions, the first primarily as a combustor/pyrolyzer bed, and the second as a combustor/filter bed. The two portions each have internal baffles to define stages so that material moving therein as fluidized beds travel in an extended route through those stages. Fluidization and movement is achieved by the introduction of gases into each stage through a directional nozzle. Gases produced in the combustor/pyrolyzer bed are permitted to travel into corresponding stages of the combustor/filter bed through screen filters that permit gas flow but inhibit solids flow. Any catalyst used in the combustor/filter bed is recycled. The two beds share a common wall to minimize total volume of the system. A slightly modified embodiment can be used for hot gas desulfurization and sorbent regeneration. Either side-by-side rectangular beds or concentric beds can be used. The system is particularly suited to the processing of radioactive and chemically hazardous waste.

New Technological Interventions in Conservation Conflicts: Countering Emotions and Contested Knowledge.

PubMed

Verma, Audrey; van der Wal, René; Fischer, Anke

2017-01-01

New technologies have increasingly featured in environmental conservation conflicts. We examined the deployment of imaging devices such as sonar equipment and cameras to survey the Fal estuary in Cornwall, UK. Due to heavy use of these waters, there have been several disputes coalescing around protected marine features, including the estuary's rare maerl beds. A comparison of two cases, scallop dredging and docks development, showed technical instruments being deployed to produce information about the marine environment as evidence to inform decision-making. The use of imaging devices stimulated political action and was regarded as a move away from emotion-based decision-making towards desired objectivity. Simultaneously, however, the process of deploying these devices was challenged and there was recognition that the resultant information could be used to construct the estuary as a politically charged space. Thus, rather than clarifying and resolving contentious issues, technological interventions generated new baselines for knowledge contestation and amplified ongoing battles for credibility and authority.

Bubbling behavior of a fluidized bed of fine particles caused by vibration-induced air inflow.

PubMed

Matsusaka, Shuji; Kobayakawa, Murino; Mizutani, Megumi; Imran, Mohd; Yasuda, Masatoshi

2013-01-01

We demonstrate that a vibration-induced air inflow can cause vigorous bubbling in a bed of fine particles and report the mechanism by which this phenomenon occurs. When convective flow occurs in a powder bed as a result of vibrations, the upper powder layer with a high void ratio moves downward and is compressed. This process forces the air in the powder layer out, which leads to the formation of bubbles that rise and eventually burst at the top surface of the powder bed. A negative pressure is created below the rising bubbles. A narrow opening at the bottom allows the outside air to flow into the powder bed, which produces a vigorously bubbling fluidized bed that does not require the use of an external air supply system.

Amine Swingbed Payload Technology Demonstration

NASA Technical Reports Server (NTRS)

Sweterlitsch, Jeffrey

2014-01-01

The Amine Swingbed is an amine-based, vacuum-regenerated adsorption technology for removing carbon dioxide and humidity from a habitable spacecraft environment, and is the baseline technology for the Orion Program’s Multi-Purpose Crew Vehicle (MPCV). It uses a pair of interleaved-layer beds filled with SA9T, the amine sorbent, and a linear multiball valve rotates 270° back and forth to control the flow of air and vacuum to adsorbing and desorbing beds. One bed adsorbs CO2 and H2O from cabin air while the other bed is exposed to vacuum for regeneration by venting the CO2 and H2O. The two beds are thermally linked, so no additional heating or cooling is required. The technology can be applied to habitable environments where recycling CO2 and H2O is not required such as short duration missions.

Bed bug detection: Current technologies and future directions

USDA-ARS?s Scientific Manuscript database

This study evaluates current technologies used to detect bed bug infestations, and presents new information regarding the underlying chemical basis of canines scent detection. The manuscript also reports new and future devices that may play a part in bed bug detection in the future....

CFD simulation of MSW combustion and SNCR in a commercial incinerator

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

Xia, Zihong; Li, Jian; Wu, Tingting

Highlights: • Presented a CFD scheme for modeling MSW incinerator including SNCR process. • Performed a sensitivity analysis of SNCR operating conditions. • Non-uniform distributions of gas velocity, temperature and NO{sub x} in the incinerator. • The injection position of reagent was critical for a desirable performance of SNCR. • A NSR 1.5 was recommended as a compromise of NO{sub x} reduction rates and NH{sub 3} slip. - Abstract: A CFD scheme was presented for modeling municipal solid waste (MSW) combustion in a moving-grate incinerator, including the in-bed burning of solid wastes, the out-of-bed burnout of gaseous volatiles, and themore » selective non-catalytic reduction (SNCR) process between urea (CO(NH{sub 2}){sub 2}) and NO{sub x}. The in-bed calculations provided 2-D profiles of the gas–solid temperatures and the gas species concentrations along the bed length, which were then used as inlet conditions for the out-of-bed computations. The over-bed simulations provided the profiles of incident radiation heat flux on the top of bed. A 3-dimensional benchmark simulation was conducted with a 750 t/day commercial incinerator using the present coupling scheme incorporating with a reduced SNCR reduction mechanism. Numerical tests were performed to investigate the effects of operating parameters such as injection position, injection speed and the normalized stoichiometric ratio (NSR) on the SNCR performance. The simulation results showed that the distributions of gas velocity, temperature and NO{sub x} concentration were highly non-uniform, which made the injection position one of the most sensitive operating parameters influencing the SNCR performance of moving grate incinerators. The simulation results also showed that multi-layer injections were needed to meet the EU2000 standard, and a NSR 1.5 was suggested as a compromise of a satisfactory NO{sub x} reduction and reasonable NH{sub 3} slip rates. This work provided useful guides to the design and operation of SNCR process in moving-grate incinerators.« less

Aquatic habitat mapping with an acoustic doppler current profiler: Considerations for data quality

USGS Publications Warehouse

Gaeuman, David; Jacobson, Robert B.

2005-01-01

When mounted on a boat or other moving platform, acoustic Doppler current profilers (ADCPs) can be used to map a wide range of ecologically significant phenomena, including measures of fluid shear, turbulence, vorticity, and near-bed sediment transport. However, the instrument movement necessary for mapping applications can generate significant errors, many of which have not been inadequately described. This report focuses on the mechanisms by which moving-platform errors are generated, and quantifies their magnitudes under typical habitat-mapping conditions. The potential for velocity errors caused by mis-alignment of the instrument?s internal compass are widely recognized, but has not previously been quantified for moving instruments. Numerical analyses show that even relatively minor compass mis-alignments can produce significant velocity errors, depending on the ratio of absolute instrument velocity to the target velocity and on the relative directions of instrument and target motion. A maximum absolute instrument velocity of about 1 m/s is recommended for most mapping applications. Lower velocities are appropriate when making bed velocity measurements, an emerging application that makes use of ADCP bottom-tracking to measure the velocity of sediment particles at the bed. The mechanisms by which heterogeneities in the flow velocity field generate horizontal velocities errors are also quantified, and some basic limitations in the effectiveness of standard error-detection criteria for identifying these errors are described. Bed velocity measurements may be particularly vulnerable to errors caused by spatial variability in the sediment transport field.

Practical Experience of Discharge Measurement in Flood Conditions with ADP

NASA Astrophysics Data System (ADS)

Vidmar, A.; Brilly, M.; Rusjan, S.

2009-04-01

Accurate discharge estimation is important for an efficient river basin management and especially for flood forecasting. The traditional way of estimating the discharge in hydrological practice is to measure the water stage and to convert the recorded water stage values into discharge by using the single-valued rating curve .Relationship between the stage and discharge values of the rating curve for the extreme events are usually extrapolated by using different mathematical methods and are not directly measured. Our practice shows that by using the Accoustic Doppler Profiler (ADP) instrument we can record the actual relation between the water stage and the flow velocity at the occurrence of flood waves very successfully. Measurement in flood conditions it is not easy task, because of high water surface velocity and large amounts of sediments in the water and floating objects on the surface like branches, bushes, trees, piles and others which can also easily damage ADP instrument. We made several measurements in such extreme events on the Sava River down to the nuclear power plant Kr\\vsko where we have install fixed cable way. During the several measurement with traditional "moving-boat" measurement technique a mowing bed phenomenon was clearly seen. Measuring flow accurately using ADP that uses the "moving-boat" technique, the system needs a reference against which to relate water velocities to. This reference is river bed and must not move. During flood events we detected difficulty finding a static bed surface to which to relate water velocities. This is caused by motion of the surface layer of bed material or also sediments suspended in the water near bed very densely. So these traditional »moving-boat« measurement techniques that we normally use completely fail. Using stationary measurement method to making individual velocity profile measurements, using an Acoustic Doppler Profiler (ADP), at certain time at fixed locations across the width of a stream gave us much better results. We use Stationary Measurement Software from SONTEK ADP manufacture to provide the tools to make USGS/ISO/WMO "Mid-Section Method" measurements using an ADP. We have ADP with 3.0 MHz which gave us 0,15m cell size in which is capable to gauge from 0,3m to a maximum depth of 6m. The beauty of using the Stationary Measurement Software is not only to overcome common moving-bed problems, but that gave us possibility to measure at depth beyond the range of the instrument. The water depth at certain profile can be inputted with known values of cross section and velocities are then extrapolated to the bed with use of velocity profile power-law equation. In practice the other good advantage to use this method is that we can repeat each profile of measurement if we detected some anomalies in the profile of measured velocities or in the case that we must quickly remove instrument from location because of floating destroying material.

Undesirable dispersal of eggs and early-stage nymphs of the bed bug Hemiptera: cimicidae) by static electricity and air currents

USDA-ARS?s Scientific Manuscript database

Movement of whole live insects or other small arthropods attributed to static electricity has been reported only rarely. While viewing bed bugs in plastic or glass Petri dishes using a dissecting microscope, individual eggs and early stage nymphs were occasionally observed to move suddenly and rapid...

Swanky Suites, More Students?

ERIC Educational Resources Information Center

Supiano, Beckie

2008-01-01

Leaders at Indiana University of Pennsylvania had heard the horror stories: Students would be accepted here, visit the campus, take one look at the outdated dormitories, and decide to go someplace else. Something had to be done. So they made the bold move to replace all student housing, bed for bed--at a cost of $270-million. The public university…

Low shear stress gravel-bed river

USGS Publications Warehouse

Milhous, Robert T.

1997-01-01

A low stress gravel bed river is a river where the cross-sectional average dimensionless shear stress (??*) rarely exceeds 0.047. That is the case for the Gunnison River below Delta in Western Colorado. The cross-sectional average ??* in the Gunnison River has not exceeded 0.047, except at one cross section during one year, in the 87 years of record. A ??* of 0.047 is the critical ??* in the bed-load equation considered to be most applicable to gravel/cobble bed rivers (the Meyer-Peter, Mueller equation). According to this equation, there has been no bed-material movement in the Gunnison River since 1920; in fact there has been bed-material movement and this movement is biologically important. Bed-material is moved when the ??* is 0.016 or larger. Streamflows that cause a ??* of at least 0.016 maintain the aquatic habitat in a low shear stress river.

Bubbling behavior of a fluidized bed of fine particles caused by vibration-induced air inflow

PubMed Central

Matsusaka, Shuji; Kobayakawa, Murino; Mizutani, Megumi; Imran, Mohd; Yasuda, Masatoshi

2013-01-01

We demonstrate that a vibration-induced air inflow can cause vigorous bubbling in a bed of fine particles and report the mechanism by which this phenomenon occurs. When convective flow occurs in a powder bed as a result of vibrations, the upper powder layer with a high void ratio moves downward and is compressed. This process forces the air in the powder layer out, which leads to the formation of bubbles that rise and eventually burst at the top surface of the powder bed. A negative pressure is created below the rising bubbles. A narrow opening at the bottom allows the outside air to flow into the powder bed, which produces a vigorously bubbling fluidized bed that does not require the use of an external air supply system. PMID:23378921

Down-flow moving-bed gasifier with catalyst recycle

DOEpatents

Halow, J.S.

1999-04-20

The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction. 1 fig.

Evaluation of center-cut separations applying simulated moving bed chromatography with 8 zones.

PubMed

Santos da Silva, Francisco Vitor; Seidel-Morgenstern, Andreas

2016-07-22

Different multi-column options to perform continuous chromatographic separations of ternary mixtures have been proposed in order to overcome limitations of batch chromatography. One attractive option is given by simulated moving bed chromatography (SMB) with 8 zones, a process that offers uninterrupted production, and, potentially, improved economy. As in other established ternary separation processes, the separation sequence is crucial for the performance of the process. This problem is addressed here by computing and comparing optimal performances of the two possibilities assuming linear adsorption isotherms. The conclusions are presented in a decision tree which can be used to guide the selection of system configuration and operation. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of Ozone MBBR Process in Refinery Wastewater Treatment

NASA Astrophysics Data System (ADS)

Lin, Wang

2018-01-01

Moving Bed Biofilm Reactor (MBBR) is a kind of sewage treatment technology based on fluidized bed. At the same time, it can also be regarded as an efficient new reactor between active sludge method and the biological membrane method. The application of ozone MBBR process in refinery wastewater treatment is mainly studied. The key point is to design the ozone +MBBR combined process based on MBBR process. The ozone +MBBR process is used to analyze the treatment of concentrated water COD discharged from the refinery wastewater treatment plant. The experimental results show that the average removal rate of COD is 46.0%~67.3% in the treatment of reverse osmosis concentrated water by ozone MBBR process, and the effluent can meet the relevant standard requirements. Compared with the traditional process, the ozone MBBR process is more flexible. The investment of this process is mainly ozone generator, blower and so on. The prices of these items are relatively inexpensive, and these costs can be offset by the excess investment in traditional activated sludge processes. At the same time, ozone MBBR process has obvious advantages in water quality, stability and other aspects.

SMART NAS Test Bed Overview

NASA Technical Reports Server (NTRS)

Palopo, Kee

2016-01-01

These slides presents an overview of SMART NAS Test Bed. The test bed is envisioned to be connected to operational systems and to allow a new concept and technology to be evaluated in its realistic environment. Its role as an accelerator of concepts and technologies development, its use-case-driven development approach, and its state are presented.

Staged fluidized bed

DOEpatents

Mallon, R.G.

1983-05-13

The invention relates to oil shale retorting and more particularly to staged fluidized bed oil shale retorting. Method and apparatus are disclosed for narrowing the distribution of residence times of any size particle and equalizing the residence times of large and small particles in fluidized beds. Particles are moved up one fluidized column and down a second fluidized column with the relative heights selected to equalize residence times of large and small particles. Additional pairs of columns are staged to narrow the distribution of residence times and provide complete processing of the material.

Application of Moving Bed Biofilm Reactor (MBBR) and Integrated Fixed Activated Sludge (IFAS) for Biological River Water Purification System: A Short Review

NASA Astrophysics Data System (ADS)

Lariyah, M. S.; Mohiyaden, H. A.; Hayder, G.; Hayder, G.; Hussein, A.; Basri, H.; Sabri, A. F.; Noh, MN

2016-03-01

This review paper present the MBBR and IFAS technology for urban river water purification including both conventional methods and new emerging technologies. The aim of this paper is to present the MBBR and IFAS technology as an alternative and successful method for treating different kinds of effluents under different condition. There are still current treatment technologies being researched and the outcomes maybe available in a while. The review also includes many relevant researches carried out at the laboratory and pilot scales. This review covers the important processes on MBBR and IFAS basic treatment process, affecting of carrier type and influent types. However, the research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. The research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. To this end, the most feasible technology could be the combination of advanced biological process (bioreactor systems) including MBBR and IFAS system.

Advanced CO2 Removal Technology Development

NASA Technical Reports Server (NTRS)

Finn, John E.; Verma, Sunita; Forrest, Kindall; LeVan, M. Douglas

2001-01-01

The Advanced CO2 Removal Technical Task Agreement covers three active areas of research and development. These include a study of the economic viability of a hybrid membrane/adsorption CO2 removal system, sorbent materials development, and construction of a database of adsorption properties of important fixed gases on several adsorbent material that may be used in CO2 removal systems. The membrane/adsorption CO2 removal system was proposed as a possible way to reduce the energy consumption of the four-bed molecular sieve system now in use. Much of the energy used by the 4BMS is used to desorb water removed in the device s desiccant beds. These beds might be replaced by a desiccating membrane that moves the water from [he incoming stream directly into the outlet stream. The approach may allow the CO2 removal beds to operate at a lower temperature. A comparison between models of the 4BMS and hybrid systems is underway at Vanderbilt University. NASA Ames Research Center has been investigating a Ag-exchanged zeolites as a possible improvement over currently used Ca and Na zeolites for CO2 removal. Silver ions will complex with n:-bonds in hydrocarbons such as ethylene, giving remarkably improved selectivity for adsorption of those materials. Bonds with n: character are also present in carbon oxides. NASA Ames is also continuing to build a database for adsorption isotherms of CO2, N2, O2, CH4, and Ar on a variety of sorbents. This information is useful for analysis of existing hardware and design of new processes.

Pneumatic transportation of dispersed medium through a vertical tube immersed into a fluidized bed

NASA Astrophysics Data System (ADS)

Krasnykh, V. Yu.; Korolev, V. N.; Ostrovskaya, A. V.; Nagornov, S. A.

2013-11-01

We discuss the technical problem of how to transport granular material in a vertical direction from the underlying section of a multistage apparatus containing a fluidized bed to an upper section through tubes immersed into the fluidized bed without additional expenditures of energy. The intensity with which the dispersed medium (a mixture of gas and fuel particles) moves through the tube and the mass flowrate of particles are determined by the ratio between the hydraulic resistances of dispersed medium inside the tube and of the fluidized bed outside of it. In turn, this ratio depends on the fluidization number W (W = w s/ w 0, where w s is the seepage velocity and w 0 is the fluidization commencement velocity) and on the tube immersing depth into the bed.

Enabling Smart Manufacturing Research and Development using a Product Lifecycle Test Bed.

PubMed

Helu, Moneer; Hedberg, Thomas

2015-01-01

Smart manufacturing technologies require a cyber-physical infrastructure to collect and analyze data and information across the manufacturing enterprise. This paper describes a concept for a product lifecycle test bed built on a cyber-physical infrastructure that enables smart manufacturing research and development. The test bed consists of a Computer-Aided Technologies (CAx) Lab and a Manufacturing Lab that interface through the product model creating a "digital thread" of information across the product lifecycle. The proposed structure and architecture of the test bed is presented, which highlights the challenges and requirements of implementing a cyber-physical infrastructure for manufacturing. The novel integration of systems across the product lifecycle also helps identify the technologies and standards needed to enable interoperability between design, fabrication, and inspection. Potential research opportunities enabled by the test bed are also discussed, such as providing publicly accessible CAx and manufacturing reference data, virtual factory data, and a representative industrial environment for creating, prototyping, and validating smart manufacturing technologies.

Enabling Smart Manufacturing Research and Development using a Product Lifecycle Test Bed

PubMed Central

Helu, Moneer; Hedberg, Thomas

2017-01-01

Smart manufacturing technologies require a cyber-physical infrastructure to collect and analyze data and information across the manufacturing enterprise. This paper describes a concept for a product lifecycle test bed built on a cyber-physical infrastructure that enables smart manufacturing research and development. The test bed consists of a Computer-Aided Technologies (CAx) Lab and a Manufacturing Lab that interface through the product model creating a “digital thread” of information across the product lifecycle. The proposed structure and architecture of the test bed is presented, which highlights the challenges and requirements of implementing a cyber-physical infrastructure for manufacturing. The novel integration of systems across the product lifecycle also helps identify the technologies and standards needed to enable interoperability between design, fabrication, and inspection. Potential research opportunities enabled by the test bed are also discussed, such as providing publicly accessible CAx and manufacturing reference data, virtual factory data, and a representative industrial environment for creating, prototyping, and validating smart manufacturing technologies. PMID:28664167

HEALTH PROFESSIONALS' USER EXPERIENCE OF THE INTELLIGENT BED IN PATIENTS' HOMES.

PubMed

Cai, Hao; Toft, Egon; Hejlesen, Ole; Hansen, John; Oestergaard, Claus; Dinesen, Birthe

2015-01-01

The intelligent bed is a medical bed with several home healthcare functions. It includes, among others, an "out of bed" detector, a moisture detector, and a catheter bag detector. The design purpose of the intelligent bed is to assist patients in their daily living, facilitate the work of clinical staff, and improves the quality of care. The aim of this sub-study of the iCare project was to explore how health professionals (HPs) experience and use the intelligent bed in patients' homes. The overall research design is inspired by case study methodology. A triangulation of data collection techniques has been used: log book, documentation study, participant observations (n = 45 hr), and qualitative interviews (n = 23). The data have been analyzed by means of Nvivo 9.0. We identified several themes: HP transformation from passive technology recipient to innovator; individualized care; work flow redesign; and sensor technology intruding on patient privacy. It is suggested that functions of the intelligent bed can result in more individualized care, workflow redesign, and time savings for the health professionals in caring for elderly patients. However, the technology intruded on patients' privacy.

Using autoregressive integrated moving average (ARIMA) models to predict and monitor the number of beds occupied during a SARS outbreak in a tertiary hospital in Singapore.

PubMed

Earnest, Arul; Chen, Mark I; Ng, Donald; Sin, Leo Yee

2005-05-11

The main objective of this study is to apply autoregressive integrated moving average (ARIMA) models to make real-time predictions on the number of beds occupied in Tan Tock Seng Hospital, during the recent SARS outbreak. This is a retrospective study design. Hospital admission and occupancy data for isolation beds was collected from Tan Tock Seng hospital for the period 14th March 2003 to 31st May 2003. The main outcome measure was daily number of isolation beds occupied by SARS patients. Among the covariates considered were daily number of people screened, daily number of people admitted (including observation, suspect and probable cases) and days from the most recent significant event discovery. We utilized the following strategy for the analysis. Firstly, we split the outbreak data into two. Data from 14th March to 21st April 2003 was used for model development. We used structural ARIMA models in an attempt to model the number of beds occupied. Estimation is via the maximum likelihood method using the Kalman filter. For the ARIMA model parameters, we considered the simplest parsimonious lowest order model. We found that the ARIMA (1,0,3) model was able to describe and predict the number of beds occupied during the SARS outbreak well. The mean absolute percentage error (MAPE) for the training set and validation set were 5.7% and 8.6% respectively, which we found was reasonable for use in the hospital setting. Furthermore, the model also provided three-day forecasts of the number of beds required. Total number of admissions and probable cases admitted on the previous day were also found to be independent prognostic factors of bed occupancy. ARIMA models provide useful tools for administrators and clinicians in planning for real-time bed capacity during an outbreak of an infectious disease such as SARS. The model could well be used in planning for bed-capacity during outbreaks of other infectious diseases as well.

The reuse of spent mushroom compost and coal tailings for energy recovery: comparison of thermal treatment technologies.

PubMed

Finney, Karen N; Ryu, Changkook; Sharifi, Vida N; Swithenbank, Jim

2009-01-01

Thermal treatment technologies were compared to determine an appropriate method of recovering energy from two wastes - spent mushroom compost and coal tailings. The raw compost and pellets of these wastes were combusted in a fluidised-bed and a packed-bed, and contrasted to pyrolysis and gasification. Quantitative combustion parameters were compared to assess the differences in efficiency between the technologies. Fluidised-bed combustion was more efficient than the packed-bed in both instances and pellet combustion was superior to that of the compost alone. Acid gas emissions (NO(x), SO(x) and HCl) were minimal for the fluidised-bed, thus little gas cleaning would be required. The fuels' high ash content (34%) also suggests fluidised-bed combustion would be preferred. The Alkali Index of the ash indicates the possibility of fouling/slagging within the system, caused by the presence of alkali metal oxides. Pyrolysis produced a range of low-calorific value-products, while gasification was not successful.

Numerical modelling of bedload sediment transport

NASA Astrophysics Data System (ADS)

Langlois, Vincent J.

2010-05-01

We present a numerical study of sediment transport in the bedload regime. Classical bedload transport laws only describe the variation of the vertically integrated flux of grains as a function of the Shields number. However, these relations are only valid if the moving layer of the bed is at equilibrium with the external flow. Besides, they do not contain enough information for many geomorphological applications. For instance, understanding inertial effects in the moving bed requires models that are able to account for the variability of hydrodynamical conditions, and the discrete nature of the sediment material. We developped a numerical modelling of the behaviour of a three-dimensional bed of grains sheared by a unidirectional fluid flow. These simulations are based on a combination of discrete and continuum approaches: sediment particles are modelled by hard spheres interacting through simple contact forces, whereas the fluid flow is described by a 'mean field' model. Both the drag exerted on grains by the fluid and the retroactive effect of the presence of grains on the flow are accounted for, allowing the system to converge to its equilibrium state (no assumption is made on the fluid velocity profile inside the layer of moving grains). Above the motion threshold, the variation of the flux of grains in the steady state is found to vary like the cube of the Shields number (as predicted by Bagnold). Besides, our simulations allow us to obtain new insights into the detailed mechanisms of bedload transport, by giving access to non-integral quantities, such as the trajectories of each individual grains, the detailed velocity and packing fraction profiles inside the granular bed, etc. It is therefore possible to investigate some effects that are not accounted for in usual continuum models, such as the polydispersity of grains, the ageing of the bed, the response to a variation of the flowrate, etc.

The optimal design of the bed structure of bedstand based on ABAQUS

NASA Astrophysics Data System (ADS)

Yang, Xudong; Dong, Yu; Ge, Qingkuan; Wang, Song

2017-12-01

Hydraulic transmission bedstand is one kind of the most commonly used in engineering machinery companies, and the bed structure is the most important part. Based on the original hydraulic transmission bedstand bed structure and the CAE technology, the original bed structure is improved. The optimized bed greatly saves the material of the production bed and improves the seismic performance of the bed. In the end, the performance of the optimized bed was compared with the original bed.

Cause and solution for false upstream boat velocities measured with a StreamPro acoustic doppler current profiler

USGS Publications Warehouse

Mueller, David S.; Rehmel, Mike S.; Wagner, Chad R.

2007-01-01

In 2003, Teledyne RD Instruments introduced the StreamPro acoustic Doppler current profiler which does not include an internal compass. During stationary moving-bed tests the StreamPro often tends to swim or kite from the end of the tether (the instrument rotates then moves laterally in the direction of the rotation). Because the StreamPro does not have an internal compass, it cannot account for the rotation. This rotation and lateral movement of the StreamPro on the end of the tether generates a false upstream velocity, which cannot be easily distinguished from a moving-bed bias velocity. A field test was completed to demonstrate that this rotation and lateral movement causes a false upstream boat velocity. The vector dot product of the boat velocity and the unit vector of the depth-averaged water velocity is shown to be an effective method to account for the effect of the rotation and lateral movement.

Bed Bug Detection: Current Technologies and Future Directions

PubMed Central

Vaidyanathan, Rajeev; Feldlaufer, Mark F.

2013-01-01

Technologies to detect bed bugs have not kept pace with their global resurgence. Early detection is critical to prevent infestations from spreading. Detection based exclusively on bites is inadequate, because reactions to insect bites are non-specific and often misdiagnosed. Visual inspections are commonly used and depend on identifying live bugs, exuviae, or fecal droplets. Visual inspections are inexpensive, but they are time-consuming and unreliable when only a few bugs are present. Use of a dog to detect bed bugs is gaining in popularity, but it can be expensive, may unintentionally advertise a bed bug problem, and is not foolproof. Passive monitors mimic natural harborages; they are discreet and typically use an adhesive to trap bugs. Active monitors generate carbon dioxide, heat, a pheromone, or a combination to attract bed bugs to a trap. New technologies using DNA analysis, mass spectrometry, and electronic noses are innovative but impractical and expensive for widespread use. PMID:23553226

Surface particle sizes on armoured gravel streambeds: Effects of supply and hydraulics

Treesearch

Peter J. Whiting; John G. King

2003-01-01

Most gravel-bed streams exhibit a surface armour in which the median grain size of the surface particles is coarser than that of the subsurface particles. This armour has been interpreted to result when the supply of sediment is less than the ability of the stream to move sediment. While there may be certain sizes in the bed for which the supply is less than the...

Perchlorate Found by Phoenix Could Provide a Mobile Brine Sludge at the Bed of Mars Northern Ice Cap that Would Allow Flow with Very Low Basal Temperatures: Possible Mechanism for Water Table Re-Charge

NASA Astrophysics Data System (ADS)

Fisher, D. A.; Hecht, M.; Kounaves, S.; Catling, D.

2009-03-01

The north cap of Mars has basal temperature that precludes the flow of ice. Phoenix discovered polar soils contain perchlorate salts. These salts depress the melting point so it could form a sludge that provides a mobile bed that moves the ice outwards.

Staged fluidized bed

DOEpatents

Mallon, Richard G.

1984-01-01

Method and apparatus for narrowing the distribution of residence times of any size particle and equalizing the residence times of large and small particles in fluidized beds. Particles are moved up one fluidized column and down a second fluidized column with the relative heights selected to equalize residence times of large and small particles. Additional pairs of columns are staged to narrow the distribution of residence times and provide complete processing of the material.

Study on an advanced early rehabilitation training system for postural control using a tilting bed

NASA Astrophysics Data System (ADS)

Yu, Chang-Ho; Kim, Kyong; Kwon, Tae-Kyu; Hong, Chul-Un; Kim, Nam-Gyun

2005-12-01

It proposed a new early rehabilitation training system for postural control using a tilting bed, a visual display and a force plate. The conventional rehabilitation systems for postural control can't be applied to the patients lying in bed because the rehabilitation training using those systems is only possible when the patient can stand up by himself or herself. Moreover, there did not exist any device that could provide the sense of balance or the sensation of walking to the patients in bed. The software for the system consists of the training program and the analysis program. The training program was designed to improve the ability of postural control of the subjects by repeated training of moving the center of pressure (COP) applied to the forceplate. The training program consists of the COP maintaining training and the COP movement training in horizontal, vertical, 45° and -45° directions. The analysis program consists of the COP moving time analysis modules, the COP maintaining time analysis module. Through the experiments with real people, it verified the effectiveness of the new early rehabilitation training system. The results showe that this system is an effective system for early rehabilitation training and that our system might be useful as clinical equipment.

Rotary plant growth accelerating apparatus. [weightlessness

NASA Technical Reports Server (NTRS)

Dedolph, R. D. (Inventor)

1975-01-01

Rotary plant growth accelerating apparatus for increasing plant yields by effectively removing the growing plants from the constraints of gravity and increasing the plant yield per unit of space is described. The apparatus is comprised of cylindrical plant beds supported radially removed from a primary axis of rotation, with each plant bed being driven about its own secondary axis of rotation and simultaneously moved in a planetary path about the primary axis of rotation. Each plant bed is formed by an apertured outer cylinder, a perforated inner cylinder positioned coaxially, and rooting media disposed in the space between. A rotatable manifold distributes liquid nutrients and water to the rooting media through the perforations in the inner cylinders as the plant beds are continuously rotated by suitable drive means.

Idealized debris flow in flume with bed driven by a conveyor belt

USGS Publications Warehouse

Ling, Chi-Hai; Chen, Cheng-lung

1989-01-01

The generalized viscoplastic fluid (GVF) model is used to derive the theoretical expressions of two-dimensional velocities and surface profile for debris flow established in a flume with bed driven by a conveyor belt. The rheological parameters of the GVF model are evaluated through the comparison of theoretical results with measured data. A slip velocity of the established (steady) nonuniform flow on the moving bed (i.e., the conveyor belt) is observed, and a relation between the slip velocity and the velocity gradient at the bed is derived. Two belts, one rough and the other smooth, were tested. The flow profile in the flume is found to be linear and dependent on the roughness of the belt, but not much on its speed.

Freshwater mussel response to bedform movement: experimental stream studies

NASA Astrophysics Data System (ADS)

Kozarek, J. L.; MacGregor, K. R.; Hornbach, D.; Hove, M.

2017-12-01

Freshwater mussels are intrinsically linked to near-bed sediment dynamics, but it remains unclear how mussels respond to changing sediment loads across spatial and temporal scales. The interactions between mussels and sediment transport are complex and often involve feedback loops. Mussels are filter feeders removing suspended particles from the water column and the physical presence of mussels can have significant impacts on the structure of riverbed habitat. We investigated the feedbacks between mussels, flow, and migrating bedforms during flood experiments in the St. Anthony Falls Laboratory Outdoor StreamLab (OSL) at the University of Minnesota. The OSL is a field-scale sand-bed meandering stream channel with independent control over sediment feed (recirculated) and water flow (diverted from the Mississippi River). Mussel location, orientation to flow, and protrusion from sediment was surveyed immediately before, after, and one and two days after each flood event. Flow fields, bed shear stress, bedform migration, and bar topography were measured during each flooding event with and without mussels present (density = 4/m2 and 8/m2) to quantify the influence of mussels on channel morphology and bedform migration. Mobile bedforms (up to 14 cm high) were present for all flood events with quasi-equilibrium, aggrading, and degrading bed conditions. Mussels moved little horizontally during all flood events, but were shown to move quickly to deeper water after the flood receded. However, mussels moved vertically, burrowing or being buried under mobile bedforms, during each flood event. The research presented here will focus on feedbacks between three mussel species with different shell sculptures, flow conditions, and migrating bedforms during flooding events. These results reveal how freshwater mussels respond to and affect flow and sediment transport during flood events that are difficult to observe in the field.

Research on acting mechanism and behavior of a gas bubble in the air dense medium fluidized bed

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

Tao, X.; Chen, Q.; Yang, Y.

1996-12-31

Coal dry beneficiation with air-dense medium fluidized bed has now been established as a high efficiency dry separation technology, it is the application of fluidization technology to the coal preparation field. The tiny particle media forms an uniform and stable fluidized bed with a density acted by airflow, which is used to separate 80{micro}m to {approximately}6mm size coal. This technology has achieved satisfied industrialization results, and attracted the expert`s attention in the field. In fluidized bed, the interaction between gas and solid was mainly decided by the existence state of heavy media particles mass (position and distance) relative velocity ofmore » gas-solid two phase, as well turbulent action. A change of vertical gas-solid fluidizing state essentially is the one of a energy transforming process. For a coal separating process with air-dense medium fluidized bed, the gas bubble, producing a turbulent and stirring action in the bed, leads to two effects. It can promote a uniform distribution of heavy media particles, and a uniform and stability of a bed density. Otherwise it will decrease effective contacts between gas-solids two phases, producing a bigger gas bubble. Therefore controlling a gas bubble size in bed should be optimized. This paper analyzes mutual movement between gas-solid, and studies the gas bubble behavior in the bed. A mechanic mode and a separating process of coal in the bed is discussed. It aims to research the coal separating mechanism with air-dense fluidized bed.« less

Advanced traffic technology test-bed.

DOT National Transportation Integrated Search

2004-06-01

The goal of this project was to create a test-bed to allow the University of California to conduct advanced traffic technology research in a designated, non-public, and controlled setting. Caltrans, with its associated research facilities on UC campu...

Behavioral Responses of the Bed Bug to Permethrin-Impregnated ActiveGuard™ Fabric.

PubMed

Jones, Susan C; Bryant, Joshua L; Harrison, Scott A

2013-06-07

ActiveGuard™ Mattress Liners have been used to control house dust mites, and they also are commercially available as an integrated pest management tool for use against bed bugs (Cimex lectularius). The aim of our study was to evaluate responses of numerous populations of the bed bug to the permethrin-impregnated fabric, with particular regard to contact toxicity, repellency, and feeding inhibition. Continuous exposure to ActiveGuard fabric resulted in rapid intoxication for three of four populations, with 87 to 100% of moderately pyrethroid-resistant and susceptible bed bugs succumbing by 1 d. In comparison, a highly resistant population reached 22% mortality at 10 d. Video data revealed that bed bugs readily traversed ActiveGuard fabric and spent a considerable amount of time moving about and resting on it during a 12-h period. ActiveGuard fabric was non-repellent to bed bugs from five tested populations. Furthermore, significantly fewer bed bugs successfully fed to repletion through ActiveGuard fabric than through blank fabric for the five populations. With just 30 min of feeding exposure, mortality ranged from 4% to 83%, depending upon the bed bug strain. These laboratory studies indicate that ActiveGuard liners adversely affected bed bugs from diverse populations.

Technology to promote safe mobility in the elderly.

PubMed

Nelson, Audrey; Powell-Cope, Gail; Gavin-Dreschnack, Deborah; Quigley, Pat; Bulat, Tatjana; Baptiste, Andrea S; Applegarth, Shawn; Friedman, Yvonne

2004-09-01

New technologies designed to help prevent adverse events related to the mobility of geriatric patients (ie, patient falls, bed-rail entrapment, patient handling, and wandering) are described. Technology offers the potential to eliminate or mitigate preventable adverse events that interfere with treatment, delay rehabilitation, potentiate impairment, and compromise patient safety. Unchecked, these adverse events can have a negative impact on patient health, functional status, and quality of life. It is not surprising that the elderly constitute the population at highest risk for adverse events, based on poor health, chronic conditions, long hospitalizations, and institutional care. Patient falls are a high-risk, high-volume, and high-cost adverse event. Key technologies to prevent falls and fall-related injuries include hip protectors, wheelchair/scooter safety features, intelligent walkers, fall alarms, and environmental aids. Bed-rail entrapment is a serious adverse event, which includes patients being trapped, entangled, or strangled in beds. New technologies to prevent bed-rail entrapment include new hospital bed designs, height-adjustable low beds, devices to close gaps in legacy beds, and bedside floor mats. Patients with mobility impairments necessitate physical assistance in transfers and other patient-handling tasks, which increases risk for the caregiver and the patient. Featured technologies to prevent patient handling injuries include innovations in floor-based lifts, new ceiling-mounted patient lifts, and improvements in powered standing lifts, new friction-reducing devices, and new patient transport technology. Wandering affects 39% of cognitively impaired nursing home residents and up to 70% of community-residing elderly persons with cognitive impairments. New technologies to prevent adverse events associated with wandering include door alarms and signal-transmitting devices. Nurses in geriatric settings would benefit from exposure to technologies that could improve patient and caregiver safety. To maximize the benefits of technology, it is critical that front-line nursing staff be involved in the testing and selection of devices that will be used in their practice. Further, to reap the full benefits of technology, a careful plan for implementation needs to be developed that would include integrating the new technology with existing infrastructure. Training needs to be provided for all staff who will be using the technology, and efforts to ensure competency over time is needed. A major barrier to widespread use of new technology is cost. Further research is needed to demonstrate the cost effectiveness of these devices. Results from these studies will help to build a business case, demonstrating that initial capital investments will result in cost savings, improved quality of care, and other benefits.

Application and Discussion of Dual Fluidized Bed Reactor in Biomass Energy Utilization

NASA Astrophysics Data System (ADS)

Guan, Haibin; Fan, Xiaoxu; Zhao, Baofeng; Yang, Liguo; Sun, Rongfeng

2018-01-01

As an important clean and renewable energy, biomass has a broad market prospect. The dual fluidized bed is widely used in biomass gasification technology, and has become an important way of biomass high-value utilization. This paper describes the basic principle of dual fluidized bed gasification, from the gas composition, tar content and thermal efficiency of the system point of view, analyzes and summarizes several typical dual fluidized bed biomass gasification technologies, points out the existence of gas mixing, the external heat source, catalyst development problems on gas. Finally, it is clear that the gasification of biomass in dual fluidized bed is of great industrial application and development prospect.

Investigation of Anaerobic Fluidized Bed Reactor/ Aerobic Moving Bed Bio Reactor (AFBR/MMBR) System for Treatment of Currant Wastewater

PubMed Central

JAFARI, Jalil; MESDAGHINIA, Alireza; NABIZADEH, Ramin; FARROKHI, Mehrdad; MAHVI, Amir Hossein

2013-01-01

Background: Anaerobic treatment methods are more suitable for the treatment of concentrated wastewater streams, offer lower operating costs, the production of usable biogas product. The aim of this study was to investigate the performance of an Anaerobic Fluidized Bed Reactor (AFBR)-Aerobic Moving Bed Bio Reactor (MBBR) in series arrangement to treat Currant wastewater. Methods: The bed materials of AFBR were cylindrical particles made of PVC with a diameter of 2–2.3 mm, particle density of 1250 kg/m3. The volume of all bed materials was 1.7 liter which expanded to 2.46 liters in fluidized situation. In MBBR, support media was composed of 1.5 liters Bee-Cell 2000 having porosity of 87% and specific surface area of 650m2/m3. Results: When system operated at 35 ºC, chemical oxygen demand (COD) removal efficiencies were achieved to 98% and 81.6% for organic loading rates (OLR) of 9.4 and 24.2 g COD/l.d, and hydraulic retention times (HRT) of 48 and 18 h, in average COD concentration feeding of 18.4 g/l, respectively. Conclusion: The contribution of AFBR in total COD removal efficiency at an organic loading rate (OLR) of 9.4 g COD/l.d was 95%, and gradually decreased to 76.5% in OLR of 24.2 g COD/l.d. Also with increasing in organic loading rate the contribution of aerobic reactor in removing COD gradually decreased. In this system, the anaerobic reactor played the most important role in the removal of COD, and the aerobic MBBR was actually needed to polish the anaerobic treated wastewater. PMID:26056640

Operation of an anaerobic filter compared with an anaerobic moving bed bioreactor for the treatment of waste water from hydrothermal carbonisation of fine mulch.

PubMed

Meier, J F; Austermann-Haun, U; Fettig, J; Liebe, H; Wichern, M

2017-10-01

This experimental study investigates the anaerobic digestion of waste water from hydrothermal carbonisation of fine mulch (wood chips) in combination with a co-substrate for the first time. Two anaerobic reactors, an anaerobic filter (AF) and an anaerobic moving bed bioreactor (AnMBBR), were operated over a period of 131 days at mesophilic conditions. The organic loading rate was increased to a maximum of 8.5 g L -l d -1 in the AF and the AnMBBR. Both reactors achieved similarly efficient chemical oxygen demand removal rates of 80% approximately (approx.) and high methane production rates of approx. 2.7 L L -1 d -1 . Nevertheless, signs of an inhibition were observed during the experiments.

Microbial shaping of sedimentary wrinkle structures

NASA Astrophysics Data System (ADS)

Mariotti, G.; Pruss, S. B.; Perron, J. T.; Bosak, T.

2014-10-01

Wrinkle structures on sandy bed surfaces were present in some of the earliest sedimentary environments, but are rare in modern environments. These enigmatic millimetre- to centimetre-scale ridges or pits are particularly common in sediments that harbour trace fossils and imprints of early animals, and appeared in the aftermath of some large mass extinctions. Wrinkle structures have been interpreted as possible remnants of microbial mats, but the formation mechanism and associated palaeoenvironmental and palaeoecological implications of these structures remain debated. Here we show that microbial aggregates can form wrinkle structures on a bed of bare sand in wave tank experiments. Waves with a small orbital amplitude at the bed surface do not move sand grains directly. However, they move millimetre-size, light microbial fragments and thereby produce linear sand ridges and rounded scour pits at the wavelengths observed in nature within hours. We conclude that wrinkle structures are morphological biosignatures that form at the sediment-water interface in wave-dominated environments, and not beneath microbial mats as previously thought. During early animal evolution, grazing by eukaryotic organisms may have temporarily increased the abundance of microbial fragments and thus the production of wrinkle structures.

Bed bug aggregation on dirty laundry: a mechanism for passive dispersal.

PubMed

Hentley, William T; Webster, Ben; Evison, Sophie E F; Siva-Jothy, Michael T

2017-09-28

Bed bugs have shown a recent and rapid global expansion that has been suggested to be caused by cheap air travel. How a small, flightless and anachoretic insect that hides within its host's sleeping area manages to travel long distances is not yet clear. Bed bugs are attracted to the odour of sleeping humans and we suggest that soiled clothing may present a similarly attractive cue, allowing bed bugs to 'hitch-hike' around the world after aggregating in the laundry bags of travellers. We show that (1) soiled clothing is significantly more attractive than clean clothing to active bed bugs moving within a bedroom sized arena and (2) elevation of CO 2 to a level that simulates human occupancy in the same arena appears to initiate search behaviour rather than direct it. Our results show, for the first time, how leaving worn clothing exposed in sleeping areas when travelling can be exploited by bed bugs to facilitate passive dispersal.

Effect of a powered drive on pushing and pulling forces when transporting bariatric hospital beds.

PubMed

Wiggermann, Neal

2017-01-01

Powered drives designed to assist with moving hospital beds are commercially available but no studies have evaluated whether they reduce the push and pull forces likely contributing to injury in caregivers. This study measured hand forces of 10 caregivers maneuvering a manual and powered bariatric bed through simulated hospital environments (hallway, elevator, and ramp). Peak push and pull forces exceeded previously established psychophysical limits for all activities with the manual bed. For the powered bed, peak forces were significantly (p < 0.05) lower for all tasks, and below psychophysical limits. Powered drive reduced peak forces between 38% (maneuvering into elevator) and 94% (descending ramp). Powered drive also reduced stopping distance by 55%. When maneuvering, the integral of hand force was 34% lower with powered drive, but average forces during straight-line pushing did not differ between beds. Powered drive may reduce the risk of injury or the number of caregivers needed for transport. Copyright © 2016 Elsevier Ltd. All rights reserved.

Method and apparatus for improving heat transfer in a fluidized bed

DOEpatents

Lessor, Delbert L.; Robertus, Robert J.

1990-01-01

An apparatus contains a fluidized bed that includes particles of different triboelectrical types, each particle type acquiring an opposite polarity upon contact. The contact may occur between particles of the two types or between particles of etiher type and structure or fluid present in the apparatus. A fluidizing gas flow is passed through the particles to produce the fluidized bed. Immersed within the bed are electrodes. An alternating EMF source connected to the electrodes applies an alternating electric field across the fluidized bed to cause particles of the first type to move relative to particles of the second type and relative to the gas flow. In a heat exchanger incorporating the apparatus, the electrodes are conduits conveying a fluid to be heated. The two particle types alternately contact each conduit to transfer heat from a hot gas flow to the second fluid within the conduit.

Improving efficiency, reducing infection, and enhancing experience.

PubMed

Massa, Judith

For health professionals to make an informed choice and tailor each bed bath to the individual needs of the patient, they must firstly understand the different bed bath options available, their impact on skin integrity, and any associated risks they may pose to the patient in terms of cross-infection. Only with this knowledge can health professionals determine the appropriate form and frequency of the bed bath. Specialist wipes offer significant improvements in skin care and a reduced risk of cross-infection, compared with the traditional soap and water bed bath. Use of these wipes also improves the efficiency of the process, which links to the Productive Ward Initiative and results in clinical staff (i.e. nursing staff, healthcare assistants) having more time available to undertake additional patient care activities. This product focus highlights the benefits of moving to a wipe-based bed bath method, and the significant efficiency savings that can be realized as a result.

Research on preventive technologies for bed-separation water hazard in China coal mines

NASA Astrophysics Data System (ADS)

Gui, Herong; Tong, Shijie; Qiu, Weizhong; Lin, Manli

2018-03-01

Bed-separation water is one of the major water hazards in coal mines. Targeted researches on the preventive technologies are of paramount importance to safe mining. This article studied the restrictive effect of geological and mining factors, such as lithological properties of roof strata, coal seam inclination, water source to bed separations, roof management method, dimensions of mining working face, and mining progress, on the formation of bed-separation water hazard. The key techniques to prevent bed-separation water-related accidents include interception, diversion, destructing the buffer layer, grouting and backfilling, etc. The operation and efficiency of each technique are corroborated in field engineering cases. The results of this study will offer reference to countries with similar mining conditions in the researches on bed-separation water burst and hazard control in coal mines.

Effect of long-term hypokinesia on the electrolytic composition of the blood in patients with osteoarticular tuberculosis

NASA Technical Reports Server (NTRS)

Zakutaeva, V. P.

1980-01-01

Seventy-six patients with osteoarticular tuberculosis were divided into two groups, one of which was required to maintain strict bed rest and the other of which was allowed unrestricted motor activity. A study of blood electrolyte composition in the two groups revealed that bed rest for these patients results in decreased plasma potassium calcium, and magnesium content, but that these indices improved after the patients were allowed to move freely. The study suggests that patients with osteoarticular tuberculosis who are on bed rest be carefully observed for alterations in blood electrolytes and that proper electrolyte balance be maintained.

PTC test bed upgrades to provide ACSES testing support capabilities at transportation technology center.

DOT National Transportation Integrated Search

2015-06-01

FRA Task Order 314 upgraded the Positive Train Control (PTC) Test Bed at the Transportation Technology Center to support : testing of PTC systems, components, and related equipment associated with the Advanced Civil Speed Enforcement System : (ACSES)...

DEMONSTRATION BULLETIN: CIRCULATING BED COMBUSTOR - OGDEN ENVIRONMENTAL SERVICES, INC.

EPA Science Inventory

An evaluation of the Ogden Environmental Services (OES) circulating bed combustor (CBC) technology was carried out under the superfund Innovative Technology Evaluation (SITE) Program to determine its applicabilitY as an on-site treatment method for waste site cleanups, and more s...

Aches and pains during pregnancy

MedlinePlus

... between 18 and 24 weeks. When you feel stretching or pain, move slowly or change positions. Mild ... common in the last months of pregnancy. Sometimes stretching your legs before bed will reduce the cramps. ...

Effectiveness of Mathematics Teaching and Learning Experiences through Wireless Technology as Recent Style to Enhance B.Ed. Trainees

ERIC Educational Resources Information Center

Joan, D. R. Robert

2015-01-01

The objective of the study was to find out the effect of learning through Wireless technologies and the traditional method in teaching and learning Mathematics. The investigator adopted experimental research to find the effectiveness of implementing Wireless technologies in the population of B.Ed. trainees. The investigator selected 32 B.Ed.…

Perched Ground Water in Zeolitized-Bedded Tuff, Rainier Mesa and Vicinity, Nevada Test Site, Nevada

USGS Publications Warehouse

Thordarson, William

1965-01-01

Rainier Mesa--site of the first series of underground nuclear detonations--is the highest of a group of ridges and mesas within the Nevada Test Site. The mesa is about 9.5 square miles in area and reaches a maximum altitude of 7,679 feet. The mesa is underlain by welded tuff, friable-bedded tuff, and zeolitized-bedded tuff of the Piapi Canyon Group and the Indian Trail Formation of Tertiary age. The tuff--2,000 to 9,000 feet thick--rests unconformably upon thrust-faulted miogeosynclinal rocks of Paleozoic age. Zeolitic-bedded tuff at the base of the tuff sequence controls the recharge rate of ground water to the underlying and more permeable Paleozoic aquifers. The zeolitic tuff--600 to 800 feet thick--is a fractured aquitard with high interstitial porosity, but with very low interstitial permeability and fracture transmissibility. The interstitial porosity ranges from 29 to 38 percent, the interstitial permeability is generally less than 0.009 gpd/ft3, and the fracture transmissibility ranges from 10 to 100 gpd/ft for 900 feet of saturated rock. The tuff is generally fully saturated interstitially hundreds of feet above the regional water table, yet no appreciable volume of water moves through the interstices because of the very low permeability. The only freely moving water observed in miles of underground workings occurred in fractures, usually fault zones.

Behavioral Responses of the Bed Bug to Permethrin-Impregnated ActiveGuard™ Fabric

PubMed Central

Jones, Susan C.; Bryant, Joshua L.; Harrison, Scott A.

2013-01-01

ActiveGuard™ Mattress Liners have been used to control house dust mites, and they also are commercially available as an integrated pest management tool for use against bed bugs (Cimex lectularius). The aim of our study was to evaluate responses of numerous populations of the bed bug to the permethrin-impregnated fabric, with particular regard to contact toxicity, repellency, and feeding inhibition. Continuous exposure to ActiveGuard fabric resulted in rapid intoxication for three of four populations, with 87 to 100% of moderately pyrethroid-resistant and susceptible bed bugs succumbing by 1 d. In comparison, a highly resistant population reached 22% mortality at 10 d. Video data revealed that bed bugs readily traversed ActiveGuard fabric and spent a considerable amount of time moving about and resting on it during a 12-h period. ActiveGuard fabric was non-repellent to bed bugs from five tested populations. Furthermore, significantly fewer bed bugs successfully fed to repletion through ActiveGuard fabric than through blank fabric for the five populations. With just 30 min of feeding exposure, mortality ranged from 4% to 83%, depending upon the bed bug strain. These laboratory studies indicate that ActiveGuard liners adversely affected bed bugs from diverse populations. PMID:26464388

Determination of the external mass transfer coefficient and influence of mixing intensity in moving bed biofilm reactors for wastewater treatment.

PubMed

Nogueira, Bruno L; Pérez, Julio; van Loosdrecht, Mark C M; Secchi, Argimiro R; Dezotti, Márcia; Biscaia, Evaristo C

2015-09-01

In moving bed biofilm reactors (MBBR), the removal of pollutants from wastewater is due to the substrate consumption by bacteria attached on suspended carriers. As a biofilm process, the substrates are transported from the bulk phase to the biofilm passing through a mass transfer resistance layer. This study proposes a methodology to determine the external mass transfer coefficient and identify the influence of the mixing intensity on the conversion process in-situ in MBBR systems. The method allows the determination of the external mass transfer coefficient in the reactor, which is a major advantage when compared to the previous methods that require mimicking hydrodynamics of the reactor in a flow chamber or in a separate vessel. The proposed methodology was evaluated in an aerobic lab-scale system operating with COD removal and nitrification. The impact of the mixing intensity on the conversion rates for ammonium and COD was tested individually. When comparing the effect of mixing intensity on the removal rates of COD and ammonium, a higher apparent external mass transfer resistance was found for ammonium. For the used aeration intensities, the external mass transfer coefficient for ammonium oxidation was ranging from 0.68 to 13.50 m d(-1) and for COD removal 2.9 to 22.4 m d(-1). The lower coefficient range for ammonium oxidation is likely related to the location of nitrifiers deeper in the biofilm. The measurement of external mass transfer rates in MBBR will help in better design and evaluation of MBBR system-based technologies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Standing wave design and optimization of a simulated moving bed chromatography for separation of xylobiose and xylose under the constraints on product concentration and pressure drop.

PubMed

Lee, Chung-Gi; Choi, Jae-Hwan; Park, Chanhun; Wang, Nien-Hwa Linda; Mun, Sungyong

2017-12-08

The feasibility of a simulated moving bed (SMB) technology for the continuous separation of high-purity xylobiose (X2) from the output of a β-xylosidase X1→X2 reaction has recently been confirmed. To ensure high economical efficiency of the X2 production method based on the use of xylose (X1) as a starting material, it is essential to accomplish the comprehensive optimization of the X2-separation SMB process in such a way that its X2 productivity can be maximized while maintaining the X2 product concentration from the SMB as high as possible in consideration of a subsequent lyophilization step. To address this issue, a suitable SMB optimization tool for the aforementioned task was prepared based on standing wave design theory. The prepared tool was then used to optimize the SMB operation parameters, column configuration, total column number, adsorbent particle size, and X2 yield while meeting the constraints on X2 purity, X2 product concentration, and pressure drop. The results showed that the use of a larger particle size caused the productivity to be limited by the constraint on X2 product concentration, and a maximum productivity was attained by choosing the particle size such that the effect of the X2-concentration limiting factor could be balanced with that of pressure-drop limiting factor. If the target level of X2 product concentration was elevated, higher productivity could be achieved by decreasing particle size, raising the level of X2 yield, and increasing the column number in the zones containing the front and rear of X2 solute band. Copyright © 2017 Elsevier B.V. All rights reserved.

Continuous recovery of valine in a model mixture of amino acids and salt from Corynebacterium bacteria fermentation using a simulated moving bed chromatography.

PubMed

Park, Chanhun; Nam, Hee-Geun; Jo, Se-Hee; Wang, Nien-Hwa Linda; Mun, Sungyong

2016-02-26

The economical efficiency of valine production in related industries is largely affected by the performance of a valine separation process, in which valine is to be separated from leucine, alanine, and ammonium sulfate. Such separation is currently handled by a batch-mode hybrid process based on ion-exchange and crystallization schemes. To make a substantial improvement in the economical efficiency of an industrial valine production, such a batch-mode process based on two different separation schemes needs to be converted into a continuous-mode separation process based on a single separation scheme. To address this issue, a simulated moving bed (SMB) technology was applied in this study to the development of a continuous-mode valine-separation chromatographic process with uniformity in adsorbent and liquid phases. It was first found that a Chromalite-PCG600C resin could be eligible for the adsorbent of such process, particularly in an industrial scale. The intrinsic parameters of each component on the Chromalite-PCG600C adsorbent were determined and then utilized in selecting a proper set of configurations for SMB units, columns, and ports, under which the SMB operating parameters were optimized with a genetic algorithm. Finally, the optimized SMB based on the selected configurations was tested experimentally, which confirmed its effectiveness in continuous separation of valine from leucine, alanine, ammonium sulfate with high purity, high yield, high throughput, and high valine product concentration. It is thus expected that the developed SMB process in this study will be able to serve as one of the trustworthy ways of improving the economical efficiency of an industrial valine production process. Copyright © 2016 Elsevier B.V. All rights reserved.

Flow regions of granules in Dorfan Impingo filter for gas cleanup

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

Kuo, J.T.; Smid, J.; Hsiau, S.S.

1999-07-01

Inside a two-dimensional model of the louvered Dorfan Impingo panel with transparent front and rear walls the flow region of filter granules without gas cross flow were observed. The white PE beads were used as filter granules. Colored PE beads served as tracers. Filter granules were discharged and circulated to the bed. The flow rate of filter medium was controlled by the belt conveyor. The image processing system including a Frame Grabber and JVC videocamera was used to record the granular flow. Every image of motion was digitized and stored in a file. The flow patterns and the quasi-stagnant zonesmore » history in the moving granular bed were evaluated. The experiment showed fast central moving region (flowing core) of filter granules and quasi-stagnant zones close to louver walls.« less

Continuous processing of recombinant proteins: Integration of inclusion body solubilization and refolding using simulated moving bed size exclusion chromatography with buffer recycling.

PubMed

Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

2013-12-06

An integrated process which combines continuous inclusion body dissolution with NaOH and continuous matrix-assisted refolding based on closed-loop simulated moving bed size exclusion chromatography was designed and experimentally evaluated at laboratory scale. Inclusion bodies from N(pro) fusion pep6His and N(pro) fusion MCP1 from high cell density fermentation were continuously dissolved with NaOH, filtered and mixed with concentrated refolding buffer prior to refolding by size exclusion chromatography (SEC). This process enabled an isocratic operation of the simulated moving bed (SMB) system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling by concentrating the raffinate using tangential flow filtration. With this continuous refolding process, we increased the refolding and cleavage yield of both model proteins by 10% compared to batch dilution refolding. Furthermore, more than 99% of the refolding buffer of the raffinate could be recycled which reduced the buffer consumption significantly. Based on the actual refolding data, we compared throughput, productivity, and buffer consumption between two batch dilution refolding processes - one using urea for IB dissolution, the other one using NaOH for IB dissolution - and our continuous refolding process. The higher complexity of the continuous refolding process was rewarded with higher throughput and productivity as well as significantly lower buffer consumption compared to the batch dilution refolding processes. Copyright © 2013 Elsevier B.V. All rights reserved.

Fluidized combustion of coal. [to limit SO2 and NOx emissions

NASA Technical Reports Server (NTRS)

Pope, M.

1978-01-01

A combustion technology that permits the burning of low quality coal, and other fuels, while maintaining stack emissions within State and Federal EPA limits is discussed. Low quality fuels can be burned directly in fluidized beds while taking advantage of low furnace temperatures and chemical activity within the bed to limit SO2 and NOx emissions. The excellent heat transfer characteristics of the fluidized beds also result in a reduction of total heat transfer surface requirements. Tests on beds operating at pressures of one to ten atmospheres, at temperatures as high as 1600 F, and with gas velocities in the vicinity of four to twelve feet per second, have proven the concept. The progress that has been made in the development of fluidized bed combustion technology and work currently underway are discussed.

Trends in infant bedding use: National Infant Sleep Position study, 1993-2010.

PubMed

Shapiro-Mendoza, Carrie K; Colson, Eve R; Willinger, Marian; Rybin, Denis V; Camperlengo, Lena; Corwin, Michael J

2015-01-01

Use of potentially hazardous bedding, as defined by the American Academy of Pediatrics (eg, pillows, quilts, comforters, loose bedding), is a modifiable risk factor for sudden infant death syndrome and unintentional sleep-related suffocation. The proportion of US infants sleeping with these types of bedding is unknown. To investigate the US prevalence of and trends in bedding use, we analyzed 1993-2010 data from the National Infant Sleep Position study. Infants reported as being usually placed to sleep with blankets, quilts, pillows, and other similar materials under or covering them in the last 2 weeks were classified as bedding users. Logistic regression was used to describe characteristics associated with bedding use. From 1993 to 2010, bedding use declined but remained a widespread practice (moving average of 85.9% in 1993-1995 to 54.7% in 2008-2010). Prevalence was highest for infants of teen-aged mothers (83.5%) and lowest for infants born at term (55.6%). Bedding use was also frequently reported among infants sleeping in adult beds, on their sides, and on a shared surface. The rate of decline in bedding use was markedly less from 2001-2010 compared with 1993-2000. For 2007 to 2010, the strongest predictors (adjusted odds ratio: ≥1.5) of bedding use were young maternal age, non-white race and ethnicity, and not being college educated. Bedding use for infant sleep remains common despite recommendations against this practice. Understanding trends in bedding use is important for tailoring safe sleep interventions. Copyright © 2015 by the American Academy of Pediatrics.

Trends in Infant Bedding Use: National Infant Sleep Position Study, 1993–2010

PubMed Central

Colson, Eve R.; Willinger, Marian; Rybin, Denis V.; Camperlengo, Lena; Corwin, Michael J.

2015-01-01

BACKGROUND: Use of potentially hazardous bedding, as defined by the American Academy of Pediatrics (eg, pillows, quilts, comforters, loose bedding), is a modifiable risk factor for sudden infant death syndrome and unintentional sleep-related suffocation. The proportion of US infants sleeping with these types of bedding is unknown. METHODS: To investigate the US prevalence of and trends in bedding use, we analyzed 1993–2010 data from the National Infant Sleep Position study. Infants reported as being usually placed to sleep with blankets, quilts, pillows, and other similar materials under or covering them in the last 2 weeks were classified as bedding users. Logistic regression was used to describe characteristics associated with bedding use. RESULTS: From 1993 to 2010, bedding use declined but remained a widespread practice (moving average of 85.9% in 1993–1995 to 54.7% in 2008–2010). Prevalence was highest for infants of teen-aged mothers (83.5%) and lowest for infants born at term (55.6%). Bedding use was also frequently reported among infants sleeping in adult beds, on their sides, and on a shared surface. The rate of decline in bedding use was markedly less from 2001–2010 compared with 1993–2000. For 2007 to 2010, the strongest predictors (adjusted odds ratio: ≥1.5) of bedding use were young maternal age, non-white race and ethnicity, and not being college educated. CONCLUSIONS: Bedding use for infant sleep remains common despite recommendations against this practice. Understanding trends in bedding use is important for tailoring safe sleep interventions. PMID:25452654

Smart Home Test Bed: Examining How Smart Homes Interact with the Power Grid

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

This fact sheet highlights the Smart Home Test Bed capability at the Energy Systems Integration Facility. The National Renewable Energy Laboratory (NREL) is working on one of the new frontiers of smart home research: finding ways for smart home technologies and systems to enhance grid operations in the presence of distributed, clean energy technologies such as photovoltaics (PV). To help advance this research, NREL has developed a controllable, flexible, and fully integrated Smart Home Test Bed.

A Study on Attitude and Opinion towards Using Computer Technology in Teaching among B.Ed. Trainees in Tiruchirappalli District

ERIC Educational Resources Information Center

Kumar, C. Ashok

2015-01-01

The main aim of the study was to find out whether there was a significant difference in the attitude and opinion towards using Computer Technology in teaching among B.Ed., trainees in terms of select independent variables. Normative survey was the technique employed. Opinion towards Computer Usage and Attitude towards Computer Technology inventory…

48 CFR 52.247-13 - Accessorial Services-Moving Contracts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... of property; e.g., beds and sectional bookcases, and the preparing of appliances; e.g., washers... uncrating and placement of property. The Contractor shall unpack and/or uncrate all property that was packed...

48 CFR 52.247-13 - Accessorial Services-Moving Contracts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of property; e.g., beds and sectional bookcases, and the preparing of appliances; e.g., washers... uncrating and placement of property. The Contractor shall unpack and/or uncrate all property that was packed...

9. Historic American Buildings Survey Josiah T. Tubby, Photographer September ...

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

9. Historic American Buildings Survey Josiah T. Tubby, Photographer September 1936 SOUTHWEST WALL EAST BED ROOM - Jefferds Tavern, Harraseekit Road (moved to U.S. Route 1A, York), Wells, York County, ME

10. Historic American Buildings Survey Josiah T. Tubby, Photographer September ...

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

10. Historic American Buildings Survey Josiah T. Tubby, Photographer September 1936 DETAIL OF MANTEL (east bed room) - Jefferds Tavern, Harraseekit Road (moved to U.S. Route 1A, York), Wells, York County, ME

Moving a patient from bed to a wheelchair

MedlinePlus

... the patient into the seat. At the same time, ask the patient to reach for the wheelchair armrest. If the patient starts to fall during the transfer, lower the person to the nearest flat surface, ...

A patient transfer apparatus between bed and stretcher.

PubMed

Wang, Hongbo; Kasagami, Fumio

2008-02-01

This paper presents a patient transfer apparatus between bed and stretcher. This apparatus makes it possible for the nurse to move weak, injured, or paralyzed patient from bed to stretcher, or vice versa, alone. Moreover, the suffering, stress, and uneasy feeling of the patient can be alleviated. This paper describes the specification, mechanical design, control system, and motion control of the apparatus. A special devised mechanism is developed, and a new servo system is used in this control system. The control principle and algorithm of the new servo system are proposed, and the motion-control method and safety function of the apparatus are described. The experimental results and evaluation indicated the effectiveness of this system.

Operation of magnetically assisted fluidized beds in microgravity and variable gravity: experiment and theory

NASA Technical Reports Server (NTRS)

Sornchamni, T.; Jovanovic, G. N.; Reed, B. P.; Atwater, J. E.; Akse, J. R.; Wheeler, R. R.

2004-01-01

The conversion of solid waste into useful resources in support of long duration manned missions in space presents serious technological challenges. Several technologies, including supercritical water oxidation, microwave powered combustion and fluidized bed incineration, have been tested for the conversion of solid waste. However, none of these technologies are compatible with microgravity or hypogravity operating conditions. In this paper, we present the gradient magnetically assisted fluidized bed (G-MAFB) as a promising operating platform for fluidized bed operations in the space environment. Our experimental and theoretical work has resulted in both the development of a theoretical model based on fundamental principles for the design of the G-MAFB, and also the practical implementation of the G-MAFB in the filtration and destruction of solid biomass waste particles from liquid streams. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Bed Surface Adjustments to Spatially Variable Flow in Low Relative Submergence Regimes

NASA Astrophysics Data System (ADS)

Monsalve, A.; Yager, E. M.

2017-11-01

In mountainous rivers, large relatively immobile grains partly control the local and reach-averaged flow hydraulics and sediment fluxes. When the flow depth is similar to the size of these grains (low relative submergence), heterogeneous flow structures and plunging flow cause spatial distributions of bed surface elevations, textures, and sedimentation rates. To explore how the bed surface responds to these flow variations we conducted a set of experiments in which we varied the relative submergence of staggered hemispheres (simulated large boulders) between runs. All experiments had the same average sediment transport capacity, upstream sediment supply, and initial bed thickness and grain size distribution. We combined our laboratory measurements with a 3-D flow model to obtain the detailed flow structure around the hemispheres. The local bed shear stress field displayed substantial variability and controlled the bed load transport rates and direction in which sediment moved. The divergence in bed shear stress caused by the hemispheres promoted size-selective bed load deposition, which formed patches of coarse sediment upstream of the hemisphere. Sediment deposition caused a decrease in local bed shear stress, which combined with the coarser grain size, enhanced the stability of this patch. The region downstream of the hemispheres was largely controlled by a recirculation zone and had little to no change in grain size, bed elevation, and bed shear stress. The formation, development, and stability of sediment patches in mountain streams is controlled by the bed shear stress divergence and magnitude and direction of the local bed shear stress field.

Effect of filter media size, mass flow rate and filtration stage number in a moving-bed granular filter on the yield and properties of bio-oil from fast pyrolysis of biomass.

PubMed

Paenpong, Chaturong; Inthidech, Sudsakorn; Pattiya, Adisak

2013-07-01

Fast pyrolysis of cassava rhizome was performed in a bench-scale fluidised-bed reactor unit incorporated with a cross-flow moving-bed granular filter. The objective of this research was to examine several process parameters including the granular size (425-1160 μm) and mass flow rate (0-12 g/min) as well as the number of the filtration stages (1-2 stages) on yields and properties of bio-oil. The results showed that the bio-oil yield decreased from 57.7 wt.% to 42.0-49.2 wt.% when increasing the filter media size, the mass flow rate and the filtration stage number. The effect of the process parameters on various properties of bio-oil is thoroughly discussed. In general, the bio-oil quality in terms of the solids content, ash content, initial viscosity, viscosity change and ageing rate could be enhanced by the hot vapour granular filtration. Therefore, bio-oil of high stability could be produced by the pyrolysis reactor configuration designed in this work. Copyright © 2013 Elsevier Ltd. All rights reserved.

Treatment of mountain refuge wastewater by fixed and moving bed biofilm systems.

PubMed

Andreottola, G; Damiani, E; Foladori, P; Nardelli, P; Ragazzi, M

2003-01-01

Tourists visiting mountain refuges in the Alps have increased significantly in the last decade and the number of refuges and huts at high altitude too. In this research the results of an intensive monitoring of a wastewater treatment plant (WWTP) for a tourist mountain refuge located at 2,981 m a.s.l. are described. Two biofilm reactors were adopted: (a) a Moving Bed Biofilm Reactor (MBBR); (b) a submerged Fixed Bed Biofilm Reactor (FBBR). The aims of this research were: (i) the evaluation of the main parameters characterising the processes and involved in the design of the wastewater plants, in order to compare advantages and disadvantages of the two tested alternatives; (ii) the acquisition of an adequate knowledge of the problems connected with the wastewater treatment in alpine refuges. The main results have been: (i) a quick start-up of the biological reactors obtainable thanks to a pre-colonization before the transportation of the plastic carriers to the refuge at the beginning of the tourist season; (ii) low volume and area requirement; (iii) significantly higher removal efficiency compared to other fixed biomass systems, such as trickling filters, but the energy consumption is higher.

Convection in deep vertically shaken particle beds. III. Convection mechanisms

NASA Astrophysics Data System (ADS)

Klongboonjit, Sakon; Campbell, Charles S.

2008-10-01

Convection in a deep vertically vibrated two-dimensional cell of granular material occurs in the form of counter-rotating cells that move material from the walls to the center of the channel and back again. At least for deep beds, where for much of the cycle, particles are in long duration contact with their neighbors, convection only appears for a short potion of every third vibrational period. That period is delimited by the interaction of three types of internal waves, a compression wave, and two types of expansion waves. Four mechanisms are identified that drive the four basic motions of convection: (1) particles move upward at the center as the result of compression wave, (2) downward at the wall as a combined effect of frictional holdback by the walls and the downward pull of gravity, (3) from the center to the walls along the free surface due to the heaping of the bed generated by the compression wave, and (4) toward the center in the interior of the box to form the bottom of convection rolls due to the relaxation of compressive stresses caused by an expansion wave. Convection only occurs when the conditions are right for all four mechanisms to be active simultaneously.

Efficiency of wastewater treatment in SBR and IFAS-MBSBBR systems in specified technological conditions.

PubMed

Sytek-Szmeichel, K; Podedworna, J; Zubrowska-Sudol, M

2016-01-01

The objective of this study is to compare wastewater treatment effectiveness in sequencing batch reactor (SBR) and integrated fixed-film activated sludge-moving-bed sequencing batch biofilm reactor (IFAS-MBSBBR) systems in specific technological conditions. The comparison of these two technologies was based on the following assumptions, shared by both series, I and II: the reactor's active volume was 28 L; 8-hour cycle of reactor's work, with the same sequence and duration of its consecutive phases; and the dissolved oxygen concentration in the aerobic phases was maintained at a level of 3.0 mg O2/L. For both experimental series (I and II), comparable effectiveness of organic compound (chemical oxygen demand (COD)) removal, nitrification and biological phosphorus removal has been obtained at levels of 95.1%, 97% and 99%, respectively. The presence of the carrier improved the efficiency of total nitrogen removal from 86.3% to 91.7%. On the basis of monitoring tests, it has been found that the ratio of simultaneous denitrification in phases with aeration to the total efficiency of denitrification in the cycle was 1.5 times higher for IFAS-MBSBBR.

Management of turbidity current venting in reservoirs under different bed slopes.

PubMed

Chamoun, Sabine; De Cesare, Giovanni; Schleiss, Anton J

2017-12-15

The lifetime and efficiency of dams is endangered by the process of sedimentation. To ensure the sustainable use of reservoirs, many sediment management techniques exist, among which venting of turbidity currents. Nevertheless, a number of practical questions remain unanswered due to a lack of systematic investigations. The present research introduces venting and evaluates its performance using an experimental model. In the latter, turbidity currents travel on a smooth bed towards the dam and venting is applied through a rectangular bottom outlet. The combined effect of outflow discharge and bed slopes on the sediment release efficiency of venting is studied based on different criteria. Several outflow discharges are tested using three different bed slopes (i.e., 0%, 2.4% and 5.0%). Steeper slopes yield higher venting efficiency. Additionally, the optimal outflow discharge leading to the largest venting efficiency with the lowest water loss increases when moving from the horizontal bed to the inclined positions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Portable bathtub: technology for bed bath in bedridden patients.

PubMed

Backes, Dirce Stein; Gomes, Carine Alves; Pereira, Simone Barbosa; Teles, Noelucy Ferreira; Backes, Marli Terezinha Stein

2017-04-01

determine the benefits of the Portable Bathtub as technology for bed bath in bedridden patients. qualitative research of exploratory-descriptive character, whose data were collected by means of 30 interviews with patients, family members and professionals directly involved in bed bath, carried out with Portable Bathtub, in bedridden patients of a medical clinic, from July to December 2015. from the data encoded by thematic content analysis resulted two categories: Portable Bathtub: from morphine to the patient's rekindled eyes; From mechanized practice to unique, transforming care. we concluded that the Portable Bathtub constitutes enhancing technology, as it enables clinical improvement of the patient's general condition and transcends traditional mechanized practices by the reach of advanced nursing care practices.

Nonlinear model predictive control applied to the separation of praziquantel in simulated moving bed chromatography.

PubMed

Andrade Neto, A S; Secchi, A R; Souza, M B; Barreto, A G

2016-10-28

An adaptive nonlinear model predictive control of a simulated moving bed unit for the enantioseparation of praziquantel is presented. A first principle model was applied at the proposed purity control scheme. The main concern about this kind of model in a control framework is in regard to the computational effort to solve it; however, a fast enough solution was achieved. In order to evaluate the controller's performance, several cases were simulated, including external pumps and switching valve malfunctions. The problem of plant-model mismatch was also investigated, and for that reason a parameter estimation step was introduced in the control strategy. In every studied scenario, the controller was able to maintain the purity levels at their set points, which were set to 99% and 98.6% for extract and raffinate, respectively. Additionally, fast responses and smooth actuation were achieved. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of a combined process of moving-bed biofilm reactor (MBBR) and chemical coagulation for dyeing wastewater treatment.

PubMed

Shin, D H; Shin, W S; Kim, Y H; Han, Myung Ho; Choi, S J

2006-01-01

A combined process consisted of a Moving-Bed Biofilm Reactor (MBBR) and chemical coagulation was investigated for textile wastewater treatment. The pilot scale MBBR system is composed of three MBBRs (anaerobic, aerobic-1 and aerobic-2 in series), each reactor was filled with 20% (v/v) of polyurethane-activated carbon (PU-AC) carrier for biological treatment followed by chemical coagulation with FeCl2. ln the MBBR process, 85% of COD and 70% of color (influent COD = 807.5 mg/L and color = 3,400 PtCo unit) were removed using relatively low MLSS concentration and short hydraulic retention time (HRT = 44 hr). The biologically treated dyeing wastewater was subjected to chemical coagulation. After coagulation with FeCl2, 95% of COD and 97% of color were removed overall. The combined process of MBBR and chemical coagulation has promising potential for dyeing wastewater treatment.

Nitrogen removal in moving bed sequencing batch reactor using polyurethane foam cubes of various sizes as carrier materials.

PubMed

Lim, Jun-Wei; Seng, Chye-Eng; Lim, Poh-Eng; Ng, Si-Ling; Sujari, Amat-Ngilmi Ahmad

2011-11-01

The performance of moving bed sequencing batch reactors (MBSBRs) added with 8 % (v/v) of polyurethane (PU) foam cubes as carrier media in nitrogen removal was investigated in treating low COD/N wastewater. The results indicate that MBSBR with 8-mL cubes achieved the highest total nitrogen (TN) removal efficiency of 37% during the aeration period, followed by 31%, 24% and 19 % for MBSBRs with 27-, 64- and 125-mL cubes, respectively. The increased TN removal in MBSBRs was mainly due to simultaneous nitrification and denitrification (SND) process which was verified by batch studies. The relatively lower TN removal in MBSBR with larger PU foam cubes was attributed to the observation that larger PU foam cubes were not fully attached by biomass. Higher concentrations of 8-mL PU foam cubes in batch reactors yielded higher TN removal. Copyright © 2011 Elsevier Ltd. All rights reserved.

Power partial-discard strategy to obtain improved performance for simulated moving bed chromatography.

PubMed

Chung, Ji-Woo; Kim, Kyung-Min; Yoon, Tae-Ung; Kim, Seung-Ik; Jung, Tae-Sung; Han, Sang-Sup; Bae, Youn-Sang

2017-12-22

A novel power partial-discard (PPD) strategy was developed as a variant of the partial-discard (PD) operation to further improve the separation performance of the simulated moving bed (SMB) process. The PPD operation varied the flow rates of discard streams by introducing a new variable, the discard amount (DA) as well as varying the reported variable, discard length (DL), while the conventional PD used fixed discard flow rates. The PPD operations showed significantly improved purities in spite of losses in recoveries. Remarkably, the PPD operation could provide more enhanced purity for a given recovery or more enhanced recovery for a given purity than the PD operation. The two variables, DA and DL, in the PPD operation played a key role in achieving the desired purity and recovery. The PPD operations will be useful for attaining high-purity products with reasonable recoveries. Copyright © 2017 Elsevier B.V. All rights reserved.

High temperature thermal energy storage in moving sand

NASA Technical Reports Server (NTRS)

Turner, R. H.; Awaya, H. I.

1978-01-01

Several high-temperature (to 500 C) heat-storage systems using sand as the storage medium are described. The advantages of sand as a storage medium include low cost for sand, widespread availability, non-toxicity, non-degradation characteristics, easy containment, and safety. The systems considered include: stationary sand with closely spaced tubes throughout the volume, the use of a fluidized bed, use of conveyor belt transporter, and the use of a blower rapid transport system. For a stationary sand bed, very close spacing of heat transfer tubes throughout the volume is required, manifesting as high power related system cost. The suggestion of moving sand past or around pipes is intended to reduce the power related costs at the penalty of added system complexity. Preliminary system cost estimates are offered. These rough calculations indicate that mobile sand heat storage systems cost less than the stationary sand approach.

Physicochemical characteristics and microbial community evolution of biofilms during the start-up period in a moving bed biofilm reactor.

PubMed

Zhu, Yan; Zhang, Yan; Ren, Hong-Qiang; Geng, Jin-Ju; Xu, Ke; Huang, Hui; Ding, Li-Li

2015-03-01

This study aimed to investigate biofilm properties evolution coupled with different ages during the start-up period in a moving bed biofilm reactor system. Physicochemical characteristics including adhesion force, extracellular polymeric substances (EPS), morphology as well as volatile solid and microbial community were studied. Results showed that the formation and development of biofilms exhibited four stages, including (I) initial attachment and young biofilm formation, (II) biofilms accumulation, (III) biofilm sloughing and updating, and (IV) biofilm maturation. During the whole start-up period, adhesion force was positively and significantly correlated with the contents of EPS, especially the content of polysaccharide. In addition, increased adhesion force and EPS were beneficial for biofilm retention. Gram-negative bacteria mainly including Sphaerotilus, Zoogloea and Haliscomenobacter were predominant in the initial stage. Actinobacteria was beneficial to resist sloughing. Furthermore, filamentous bacteria were dominant in maturation biofilm. Copyright © 2015 Elsevier Ltd. All rights reserved.

ISS Benefits for Humanity: Train Like an Astronaut

NASA Image and Video Library

2015-01-29

Published on Jan 29, 2015 Developed in cooperation with NASA scientists and fitness professionals working directly with astronauts, the Train Like an Astronaut program is an exciting and engaging way to get the children of today up and moving. The project uses the excitement of exploration to challenge students to set physical fitness and research goals, practice physical fitness activities, and research proper nutrition, enabling each child to become our next generation of fit explorers! The International Space Station is a blueprint for global cooperation and scientific advancements, a destination for a growing commercial marketplace in low-Earth orbit and a test bed for demonstrating new technologies. The space station is the springboard to NASA’s next great leap in exploration, including future missions to an asteroid and Mars. For more information: http://go.nasa.gov/1zhkuW9

Experimental Exploration of Scale Effects and Factors Controlling Bed Load Sediment Entrainment

NASA Astrophysics Data System (ADS)

Fathel, S. L.; Furbish, D. J.; Schmeeckle, M. W.

2015-12-01

Detailed measurements of individual sand grains moving on a streambed allow us to obtain a deeper understanding of the characteristics of incipient motion and evaluate spatial and temporal trends in particle entrainment. We use bed load particle motions measured from high-speed imaging (250 Hz) of uniform, coarse grained sand from two flume experiments, which have different mean fluid velocities near the bed. Particle tracking reveals more than 6,000 entrainment events in 5 seconds (Run 1) and over 5,000 events in 2 seconds (Run 2). We manually track particles, at sub-pixel resolution, from entrainment to either disentrainment or until the particle leaves the frame. Within these experiments we find that over 90% of all initial motions contain a cross-stream component of motion where approximately a third of the motions may be cross-stream dominated, and furthermore, up to 7% of the motions may be negative (i.e. move backwards). We propose that the variability in the direction of initial motion is, in part, a product of the bed topography, where we find that with increasing mean fluid velocity, the initial motion of the sand particles are less sensitive to bed topography, and are more likely to be dominated by the fluid. The high resolution of this data set, containing positions of particles measured start-to-stop, allows us to calculate the characteristic timescale required for a particle to become streamwise, or fluid, dominated in these systems. We also evaluate these data to further show whether the nature of entrainment is a memoryless, uncorrelated process, a correlated process related to the number of particles already in motion (i.e., possibly reflecting collective entrainment), or some combination of the two. This work suggests that the probability of entrainment depends on physical factors such as bed microtopography and the magnitude of the fluid velocity, in addition to varying with space and time scales.

Repellency of selected chemicals against the bed bug (Hemiptera: Cimicidae).

PubMed

Wang, Changlu; Lü, Lihua; Zhang, Aijun; Liu, Chaofeng

2013-12-01

In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help achieve these goals by discouraging and preventing bed bugs from moving to a protected area. We evaluated the repellency of three commercially available insect repellent or control materials and five nonregistered materials with the goal of identifying safe and effective bed bug repellents. The two commercial repellent products that contained 7% picaridin or 0.5% permethrin had little repellency against bed bugs. N,N-diethyl-m-toluamide (DEET), the most commonly used insect repellent, provided a high level of repellency against bed bugs. When a host cue (carbon dioxide) was present, the minimum DEET concentration to repel > or = 94% of the bed bugs for a9-h period was 10%. The longevity of repellency of DEET was concentration dependent. At 25% concentration, DEET-treated fabric surface remained highly repellent to bed bugs for a 14-d period. However, DEET has a strong smell and dissolves certain plastic materials. Therefore, we evaluated several odorless, noncorrosive, and potentially effective repellents. Isolongifolenone and isolongifolanone, two natural products and recently reported insect repellents, exhibited strong repellent property against bed bugs but at significantly lower levels than DEET. Three novel potential repellent compounds discovered by Bedoukian Research Inc. (Danbury, CT) exhibited similar level of repellency and longevity as DEET for repelling bed bugs. These nonirritant and odorless compounds are promising candidates as alternatives to DEET for reducing the spread of bed bugs and bed bug bites.

Transient infrared spectroscopy for detection of toxigenic fungi in corn: potential for on-line evaluation.

PubMed

Gordon, S H; Jones, R W; McClelland, J F; Wicklow, D T; Greene, R V

1999-12-01

An urgent need for rapid sensors to detect contamination of food grains by toxigenic fungi such as Aspergillus flavus prompted research and development of Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) as a highly sensitive probe for fungi growing on the surfaces of individual corn kernels. However, the photoacoustic technique has limited potential for screening bulk corn because currently available photoacoustic detectors can accommodate only a single intact kernel at a time. Transient infrared spectroscopy (TIRS), on the other hand, is a promising new technique that can acquire analytically useful infrared spectra from a moving mass of solid materials. Therefore, the potential of TIRS for on-line, noncontact detection of A. flavus contamination in a moving bed of corn kernels was explored. Early test results based on visual inspection of TIRS spectral differences predict an 85% or 95% success rate in distinguishing healthy corn from grain infected with A. flavus. Four unique infrared spectral features which identified infected corn in FTIR-PAS were also found to be diagnostic in TIRS. Although the technology is still in its infancy, the preliminary results indicate that TIRS is a potentially effective screening method for bulk quantities of corn grain.

The effect of coarse gravel on cohesive sediment entrapment in an annular flume

NASA Astrophysics Data System (ADS)

Glasbergen, K.; Stone, M.; Krishnappan, B.; Dixon, J.; Silins, U.

2015-03-01

While cohesive sediment generally represents a small fraction (<0.5%) of the total sediment mass stored in gravel-bed rivers, it can strongly influence physical and biogeochemical processes in the hyporheic zone and alter aquatic habitat. This research was conducted to examine mechanisms governing the interaction of cohesive sediments with gravel beds in the Elbow River, Alberta, Canada. A series of erosion and deposition experiments with and without a gravel bed were conducted in a 5-m diameter annular flume. The critical shear stress for deposition and erosion of cohesive sediment without gravel was 0.115 Pa and 0.212 Pa, respectively. In experiments with a gravel bed, cohesive sediment moved from the water column into the gravel bed via the coupling of surface and pore water flow. Once in the gravel bed, cohesive sediments were not mobilized under the maximum applied shear stresses (1.11 Pa) used in the experiment. The gravel bed had an entrapment coefficient (ratio between the entrapment flux and the settling flux) of 0.2. Accordingly, when flow conditions are sufficient to produce a shear stress that will mobilize the armour layer of the gravel bed (>16 Pa), cohesive materials trapped within the gravel bed will be entrained and transported into the Glenmore Reservoir, where sediment-associated nutrients may pose treatment challenges to the drinking water supply.

Bed material transport in the Virgin River, Utah

USGS Publications Warehouse

Andrews, E.D.

2000-01-01

Detailed information concerning the rate and particle size distribution of bed material transport by streamflows can be very difficult and expensive to obtain, especially where peak streamflows are brief and bed material is poorly sorted, including some very large boulders. Such streams, however, are common in steep, arid watersheds. Any computational approach must consider that (1) only the smaller particle sizes present on the streambed move even during large floods and (2) the largest bed particles exert a significant form drag on the flow. Conventional methods that rely on a single particle size to estimate the skin friction shear stress acting on the mobile fraction of the bed material perform poorly. Instead, for this study, the skin friction shear stress was calculated for the observed range of streamflows by calculating the form drag exerted on the reach‐averaged flow field by all particle sizes. Suspended and bed load transported rates computed from reach‐averaged skin friction shear stress are in excellent agreement with measured transport rates. The computed mean annual bed material load, including both bed load and suspended load, of the East Fork Virgin River for the water years 1992‐1996 was approximately 1.3×10 5 t. A large portion of the bed material load consists of sand‐sized particles, 0.062–1.0 mm in diameter, that are transported in suspension. Such particles, however, constituted only 10% of the surface bed material and less than 25% of the subsurface bed material. The mean annual quantity of bed load transported was 1060 t/yr with a median size of 15 mm.

Nonspherical particles in a pseudo-2D fluidized bed: Experimental study.

PubMed

Mahajan, Vinay V; Padding, Johan T; Nijssen, Tim M J; Buist, Kay A; Kuipers, J A M

2018-05-01

Fluidization is widely used in industries and has been extensively studied, both experimentally and theoretically, in the past. However, most of these studies focus on spherical particles while in practice granules are rarely spherical. Particle shape can have a significant effect on fluidization characteristics. It is therefore important to study the effect of particle shape on fluidization behavior in detail. In this study, experiments in pseudo-2D fluidized beds are used to characterize the fluidization of spherocylindrical (rod-like) Geldart D particles of aspect ratio 4. Pressure drop and optical measurement methods (Digital Image Analysis, Particle Image Velocimetry, Particle Tracking Velocimetry) are employed to measure bed height, particle orientation, particle circulation, stacking, and coordination number. The commonly used correlations to determine the pressure drop across a bed of nonspherical particles are compared to experiments. Experimental observations and measurements have shown that rod-like particles are prone to interlocking and channeling behavior. Well above the minimum fluidization velocity, vigorous bubbling fluidization is observed, with groups of interlocked particles moving upwards, breaking up, being thrown high in the freeboard region and slowly raining down as dispersed phase. At high flowrates, a circulation pattern develops with particles moving up through the center and down at the walls. Particles tend to orient themselves along the flow direction. © 2018 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers , 64: 1573-1590, 2018.

Nonspherical particles in a pseudo‐2D fluidized bed: Experimental study

PubMed Central

Mahajan, Vinay V.; Nijssen, Tim M. J.; Buist, Kay A.; Kuipers, J. A. M.

2018-01-01

Fluidization is widely used in industries and has been extensively studied, both experimentally and theoretically, in the past. However, most of these studies focus on spherical particles while in practice granules are rarely spherical. Particle shape can have a significant effect on fluidization characteristics. It is therefore important to study the effect of particle shape on fluidization behavior in detail. In this study, experiments in pseudo‐2D fluidized beds are used to characterize the fluidization of spherocylindrical (rod‐like) Geldart D particles of aspect ratio 4. Pressure drop and optical measurement methods (Digital Image Analysis, Particle Image Velocimetry, Particle Tracking Velocimetry) are employed to measure bed height, particle orientation, particle circulation, stacking, and coordination number. The commonly used correlations to determine the pressure drop across a bed of nonspherical particles are compared to experiments. Experimental observations and measurements have shown that rod‐like particles are prone to interlocking and channeling behavior. Well above the minimum fluidization velocity, vigorous bubbling fluidization is observed, with groups of interlocked particles moving upwards, breaking up, being thrown high in the freeboard region and slowly raining down as dispersed phase. At high flowrates, a circulation pattern develops with particles moving up through the center and down at the walls. Particles tend to orient themselves along the flow direction. © 2018 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 64: 1573–1590, 2018 PMID:29706659

Using a Medical Intranet of Things System to Prevent Bed Falls in an Acute Care Hospital: A Pilot Study.

PubMed

Balaguera, Henri U; Wise, Diana; Ng, Chun Yin; Tso, Han-Wen; Chiang, Wan-Lin; Hutchinson, Aimee M; Galvin, Tracy; Hilborne, Lee; Hoffman, Cathy; Huang, Chi-Cheng; Wang, C Jason

2017-05-04

Hospitalized patients in the United States experience falls at a rate of 2.6 to 17.1 per 1000 patient-days, with the majority occurring when a patient is moving to, from, and around the bed. Each fall with injury costs an average of US $14,000. The aim was to conduct a technology evaluation, including feasibility, usability, and user experience, of a medical sensor-based Intranet of things (IoT) system in facilitating nursing response to bed exits in an acute care hospital. Patients 18 years and older with a Morse fall score of 45 or greater were recruited from a 35-bed medical-surgical ward in a 317-bed Massachusetts teaching hospital. Eligible patients were recruited between August 4, 2015 and July 31, 2016. Participants received a sensor pad placed between the top of their mattress and bed sheet. The sensor pad was positioned to monitor movement from patients' shoulders to their thighs. The SensableCare System was evaluated for monitoring patient movement and delivering timely alerts to nursing staff via mobile devices when there appeared to be a bed-exit attempt. Sensor pad data were collected automatically from the system. The primary outcomes included number of falls, time to turn off bed-exit alerts, and the number of attempted bed-exit events. Data on patient falls were collected by clinical research assistants and confirmed with the unit nurse manager. Explanatory variables included room locations (zones 1-3), day of the week, nursing shift, and Morse Fall Scale (ie, positive fall history, positive secondary diagnosis, positive ambulatory aid, weak impaired gait/transfer, positive IV/saline lock, mentally forgets limitations). We also assessed user experience via nurse focus groups. Qualitative data regarding staff interactions with the system were collected during two focus groups with 25 total nurses, each lasting approximately 1.5 hours. A total of 91 patients used the system for 234.0 patient-days and experienced no bed falls during the study period. On average, patients were assisted/returned to bed 46 seconds after the alert system was triggered. Response times were longer during the overnight nursing shift versus day shift (P=.005), but were independent of the patient's location on the unit. Focus groups revealed that nurses found the system integrated well into the clinical nursing workflow and the alerts were helpful in patient monitoring. A medical IoT system can be integrated into the existing nursing workflow and may reduce patient bed fall risk in acute care hospitals, a high priority but an elusive patient safety challenge. By using an alerting system that sends notifications directly to nurses' mobile devices, nurses can equally respond to unassisted bed-exit attempts wherever patients are located on the ward. Further study, including a fully powered randomized controlled trial, is needed to assess effectiveness across hospital settings. ©Henri U Balaguera, Diana Wise, Chun Yin Ng, Han-Wen Tso, Wan-Lin Chiang, Aimee M Hutchinson, Tracy Galvin, Lee Hilborne, Cathy Hoffman, Chi-Cheng Huang, C Jason Wang. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 04.05.2017.

Application of the dynamic model of Saeman to an industrial rotary kiln incinerator: numerical and experimental results.

PubMed

Ndiaye, L G; Caillat, S; Chinnayya, A; Gambier, D; Baudoin, B

2010-07-01

In order to simulate granular materials structure in a rotary kiln under the steady-state regime, a mathematical model has been developed by Saeman (1951). This model enables the calculation of the bed profiles, the axial velocity and solids flow rate along the kiln. This model can be coupled with a thermochemical model, in the case of a reacting moving bed. This dynamic model was used to calculate the bed profile for an industrial size kiln and the model projections were validated by measurements in a 4 m diameter by 16 m long industrial rotary kiln. The effect of rotation speed under solids bed profile and the effect of the feed rate under filling degree were established. On the basis of the calculations and the experimental results a phenomenological relation for the residence time estimation was proposed for the rotary kiln. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Near-infrared spectroscopy monitoring and control of the fluidized bed granulation and coating processes-A review.

PubMed

Liu, Ronghua; Li, Lian; Yin, Wenping; Xu, Dongbo; Zang, Hengchang

2017-09-15

The fluidized bed granulation and pellets coating technologies are widely used in pharmaceutical industry, because the particles made in a fluidized bed have good flowability, compressibility, and the coating thickness of pellets are homogeneous. With the popularization of process analytical technology (PAT), real-time analysis for critical quality attributes (CQA) was getting more attention. Near-infrared (NIR) spectroscopy, as a PAT tool, could realize the real-time monitoring and control during the granulating and coating processes, which could optimize the manufacturing processes. This article reviewed the application of NIR spectroscopy in CQA (moisture content, particle size and tablet/pellet thickness) monitoring during fluidized bed granulation and coating processes. Through this review, we would like to provide references for realizing automated control and intelligent production in fluidized bed granulation and pellets coating of pharmaceutical industry. Copyright © 2017 Elsevier B.V. All rights reserved.

Pulling a patient up in bed

MedlinePlus

... from rubbing can scrape or tear the person's skin. Common areas at risk for friction are the shoulders, back, buttocks, elbows, and heels. Never move patients up by grabbing them under their arms and pulling. This can injure their shoulders.

Evaluating De-centralised and Distributional Options for the Distributed Electronic Warfare Situation Awareness and Response Test Bed

DTIC Science & Technology

2013-12-01

effectors (deployed on ground based or aerial platforms) to detect , identify, locate, track or suppress stationary or slow moving surface based RF...ground based or aerial platforms) to detect , identify, locate, track or suppress stationary or slow moving surface based RF emitting targets. In the...Electronic Support EO Electro-Optic FPGAs Field Programmable Gate Arrays IR Infra-red LADAR Laser Detection and Ranging OSX Mac OS X; the apple

Evaluation of multiple-frequency, active and passive acoustics as surrogates for bedload transport

USGS Publications Warehouse

Wood, Molly S.; Fosness, Ryan L.; Pachman, Gregory; Lorang, Mark; Tonolla, Diego

2015-01-01

The use of multiple-frequency, active acoustics through deployment of acoustic Doppler current profilers (ADCPs) shows potential for estimating bedload in selected grain size categories. The U.S. Geological Survey (USGS), in cooperation with the University of Montana (UM), evaluated the use of multiple-frequency, active and passive acoustics as surrogates for bedload transport during a pilot study on the Kootenai River, Idaho, May 17-18, 2012. Four ADCPs with frequencies ranging from 600 to 2000 kHz were used to measure apparent moving bed velocities at 20 stations across the river in conjunction with physical bedload samples. Additionally, UM scientists measured the sound frequencies of moving particles with two hydrophones, considered passive acoustics, along longitudinal transects in the study reach. Some patterns emerged in the preliminary analysis which show promise for future studies. Statistically significant relations were successfully developed between apparent moving bed velocities measured by ADCPs with frequencies 1000 and 1200 kHz and bedload in 0.5 to 2.0 mm grain size categories. The 600 kHz ADCP seemed somewhat sensitive to the movement of gravel bedload in the size range 8.0 to 31.5 mm, but the relation was not statistically significant. The passive hydrophone surveys corroborated the sample results and could be used to map spatial variability in bedload transport and to select a measurement cross-section with moving bedload for active acoustic surveys and physical samples.

Exergy optimization in a steady moving bed heat exchanger.

PubMed

Soria-Verdugo, A; Almendros-Ibáñez, J A; Ruiz-Rivas, U; Santana, D

2009-04-01

This work provides an energy and exergy optimization analysis of a moving bed heat exchanger (MBHE). The exchanger is studied as a cross-flow heat exchanger where one of the phases is a moving granular medium. The optimal MBHE dimensions and the optimal particle diameter are obtained for a range of incoming fluid flow rates. The analyses are carried out over operation data of the exchanger obtained in two ways: a numerical simulation of the steady-state problem and an analytical solution of the simplified equations, neglecting the conduction terms. The numerical simulation considers, for the solid, the convection heat transfer to the fluid and the diffusion term in both directions, and for the fluid only the convection heat transfer to the solid. The results are compared with a well-known analytical solution (neglecting conduction effects) for the temperature distribution in the exchanger. Next, the analytical solution is used to derive an expression for the exergy destruction. The optimal length of the MBHE depends mainly on the flow rate and does not depend on particle diameter unless they become very small (thus increasing sharply the pressure drop). The exergy optimal length is always smaller than the thermal one, although the difference is itself small.

Effects of a malfunctional column on conventional and FeedCol-simulated moving bed chromatography performance.

PubMed

Song, Ji-Yeon; Oh, Donghoon; Lee, Chang-Ha

2015-07-17

The effects of a malfunctional column on the performance of a simulated moving bed (SMB) process were studied experimentally and theoretically. The experimental results of conventional four-zone SMB (2-2-2-2 configuration) and FeedCol operation (2-2-2-2 configuration with one feed column) with one malfunctional column were compared with simulation results of the corresponding SMB processes with a normal column configuration. The malfunctional column in SMB processes significantly deteriorated raffinate purity. However, the extract purity was equivalent or slightly improved compared with the corresponding normal SMB operation because the complete separation zone of the malfunctional column moved to a lower flow rate range in zones II and III. With the malfunctional column configuration, FeedCol operation gave better experimental performance (up to 7%) than conventional SMB operation because controlling product purity with FeedCol operation was more flexible through the use of two additional operating variables, injection time and injection length. Thus, compared with conventional SMB separation, extract with equivalent or slightly better purity could be produced from FeedCol operation even with a malfunctional column, while minimizing the decrease in raffinate purity (less than 2%). Copyright © 2015 Elsevier B.V. All rights reserved.

Development of the Methane Hydrate Burning Experimental Equipment

NASA Astrophysics Data System (ADS)

Aoyama, S.

2010-12-01

There is a need to increase understanding among Japanese citizens about the importance as a potential future energy source of the great quantity of methane hydrate deposits sleeping on the sea bed around Japan. With cooperation from the Japan Oil, Gas and Metals National Corporation (JOGMEC), the National Institute of Advanced Industrial Science and Technology (AIST), and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) we studied the possibility of using presentations where it was possible to handle actual methane hydrate, videos and active presentations such as experiments in order to increase the public interest in and understanding of methane hydrate. Furthermore, for the benefit of those people who would like to visit the exhibition but are unable to do so due to distance or other physical barriers, we looked into making the presentation materials portable and having a moving exhibition. Currently methane hydrate combustion experiments and exhibition performances are being held at the Hidaka Port New Energy Park (The Kansai Electric Power Co., Inc.) in Gobo, Wakayama with approximately 3,000 visitors monthly.

Quantifying fluid and bed dynamics for characterizing benthic physical habitat in large rivers

USGS Publications Warehouse

Gaeuman, D.; Jacobson, R.B.

2007-01-01

Sturgeon use benthic habitats in and adjacent to main channels where environmental conditions can include bedload sediment transport and high near-bed flow velocities. Bed velocity measurements obtained with acoustic Doppler instruments provide a means to assess the concentration and velocity of sediment moving near the streambed, and are thus indicative of the bedload sediment transport rate, the near-bed flow velocity, and the stability of the substrate. Acoustic assessments of benthic conditions in the Missouri River were conducted at scales ranging from the stream reach to individual bedforms. Reach-scale results show that spatially-averaged bed velocities in excess of 0.5 m s-1 frequently occur in the navigation channel. At the local scale, bed velocities are highest near bedform crests, and lowest in the troughs. Low-velocity zones can persist in areas with extremely high mean bed velocities. Use of these low-velocity zones may allow sturgeon to make use of portions of the channel where the average conditions near the bed are severe. To obtain bed velocity measurements of the highest possible quality, it is necessary to extract bottom-track and GPS velocity information from the raw ADCP data files on a ping-by-ping basis. However, bed velocity measured from a point can also be estimated using a simplified method that is more easily implemented in the context of routine monitoring. The method requires only the transect distance and direction data displayed in standard ADCP data-logging software. Bed velocity estimates obtained using this method are usually within 5-10% of estimates obtained from ping-by-ping processing. ?? 2007 Blackwell Verlag.

Experimental Studies in a Reconfigurable C4 Test-bed for Network Enabled Capability

DTIC Science & Technology

2006-06-01

Cross1, Dr R. Houghton1, and Mr R. McMaster1 Defence Technology Centre for Human factors Integration (DTC HFI ) BITlab, School of Engineering and Design...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Defence Technology Centre for Human factors Integration (DTC HFI ) BITlab, School of...studies into NEC by the Human Factors Integration Defence Technology Centre ( HFI -DTC). DEVELOPMENT OF THE TESTBED In brief, the C4 test-bed

Fluidized bed and method and system for gas component capture

DOEpatents

Krutka, Holly; Wilson, Cody; Starns, Travis

2016-05-31

The present disclosure is directed to a process that allows dry sorbents to remove a target constituent, such as carbon dioxide (CO.sub.2), from a gas stream. A staged fluidized bed separator enables gas and sorbent to move in opposite directions. The sorbent is loaded with target constituent in the separator. It is then transferred to a regenerator where the target constituent is stripped. The temperature of the separator and regenerator are controlled. After it is removed from the regenerator, the sorbent is then transferred back to the separator.

Biomass waste gasification - Can be the two stage process suitable for tar reduction and power generation?

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

Sulc, Jindrich; Stojdl, Jiri; Richter, Miroslav

2012-04-15

Highlights: Black-Right-Pointing-Pointer Comparison of one stage (co-current) and two stage gasification of wood pellets. Black-Right-Pointing-Pointer Original arrangement with grate-less reactor and upward moving bed of the pellets. Black-Right-Pointing-Pointer Two stage gasification leads to drastic reduction of tar content in gas. Black-Right-Pointing-Pointer One stage gasification produces gas with higher LHV at lower overall ER. Black-Right-Pointing-Pointer Content of ammonia in gas is lower in two stage moving bed gasification. - Abstract: A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stagemore » gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW{sub th}. The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950 Degree-Sign C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER = 0.71) led to substantial reduction of gas heating value (LHV = 3.15 MJ/Nm{sup 3}), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950 Degree-Sign C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the second stage presented only few mass% of the inlet biomass stream.« less

Production of Monosugars from Lignocellulosic Biomass in Molten Salt Hydrates: Process Design and Techno-Economic Analysis

PubMed Central

2017-01-01

ZnCl2 hydrate, the main molten salt used in biomass conversion, combined with low concentration HCl is an excellent solvent for the dissolution and hydrolysis of the carbohydrates present in lignocellulosic biomass. The most recalcitrant carbohydrate, cellulose, is dissolved in a residence time less than 1 h under mild conditions without significant degradation. This technology is referred to as BIOeCON-solvent technology. Separation of the sugars from the solution is the main challenge. The earlier conclusion regarding the potential of zeolite beta for selective adsorption has been used as the basis of a scale-up study. The technology of choice is continuous chromatographic separation (e.g., simulated moving bed, SMB). The sugar monomers are separated from the sugar oligomers, allowing the production of monosugars at high yield, using water as an eluent. Results of a pilot plant study are presented showing a stable operation at high selectivity. Several process designs are discussed, and the techno-economic performance of the BIOeCON-solvent technology is demonstrated by comparison with the state-of-the-art technology of NREL (National Renewable Energy Laboratory), which is based on enzymatic conversion of cellulose. It is concluded that the BIOeCON-solvent technology is technically and economically viable and is competitive to the NREL process. Because the BIOeCON-solvent process is in an early stage of development and far from fully optimized, it has the potential to outperform the existing processes. PMID:29170600

Production of Monosugars from Lignocellulosic Biomass in Molten Salt Hydrates: Process Design and Techno-Economic Analysis.

PubMed

van den Bergh, Johan; Babich, Igor V; O'Connor, Paul; Moulijn, Jacob A

2017-11-15

ZnCl 2 hydrate, the main molten salt used in biomass conversion, combined with low concentration HCl is an excellent solvent for the dissolution and hydrolysis of the carbohydrates present in lignocellulosic biomass. The most recalcitrant carbohydrate, cellulose, is dissolved in a residence time less than 1 h under mild conditions without significant degradation. This technology is referred to as BIOeCON-solvent technology. Separation of the sugars from the solution is the main challenge. The earlier conclusion regarding the potential of zeolite beta for selective adsorption has been used as the basis of a scale-up study. The technology of choice is continuous chromatographic separation (e.g., simulated moving bed, SMB). The sugar monomers are separated from the sugar oligomers, allowing the production of monosugars at high yield, using water as an eluent. Results of a pilot plant study are presented showing a stable operation at high selectivity. Several process designs are discussed, and the techno-economic performance of the BIOeCON-solvent technology is demonstrated by comparison with the state-of-the-art technology of NREL (National Renewable Energy Laboratory), which is based on enzymatic conversion of cellulose. It is concluded that the BIOeCON-solvent technology is technically and economically viable and is competitive to the NREL process. Because the BIOeCON-solvent process is in an early stage of development and far from fully optimized, it has the potential to outperform the existing processes.

Manufacturing Solid Dosage Forms from Bulk Liquids Using the Fluid-bed Drying Technology.

PubMed

Qi, Jianping; Lu, Y I; Wu, Wei

2015-01-01

Solid dosage forms are better than liquid dosage forms in many ways, such as improved physical and chemical stability, ease of storage and transportation, improved handling properties, and patient compliance. Therefore, it is required to transform dosage forms of liquid origins into solid dosage forms. The functional approaches are to absorb the liquids by solid excipients or through drying. The conventional drying technologies for this purpose include drying by heating, vacuum-, freeze- and spray-drying, etc. Among these drying technologies, fluidbed drying emerges as a new technology that possesses unique advantages. Fluid-bed drying or coating is highly efficient in solvent removal, can be performed at relatively low temperatures, and is a one-step process to manufacture formulations in pellet forms. In this article, the status of the art of manufacturing solid dosage forms from bulk liquids by fluid-bed drying technology was reviewed emphasizing on its application in solid dispersion, inclusion complexes, self-microemulsifying systems, and various nanoscale drug delivery systems.

Technology test bed review

NASA Technical Reports Server (NTRS)

Mcconnaughey, H. V.

1992-01-01

The topics are presented in viewgraph form and include the following: (1) Space Shuttle Main Engine (SSME) technology test bed (TTB) history; (2) TTB objectives; (3) TTB major accomplishments; (4) TTB contributions to SSME; (5) major impacts of 3001 testing; (6) some challenges to computational fluid dynamics (CFD); (7) the high pressure fuel turbopump (HPFTP); and (8) 3001 lessons learned in design and operations.

Transport of fine sediment over a coarse, immobile riverbed

USGS Publications Warehouse

Grams, Paul E.; Wilcock, Peter R.

2014-01-01

Sediment transport in cobble-boulder rivers consists mostly of fine sediment moving over a coarse, immobile bed. Transport rate depends on several interrelated factors: boundary shear stress, the grain size and volume of fine sediment, and the configuration of fine sediment into interstitial deposits and bed forms. Existing models do not incorporate all of these factors. Approaches that partition stress face a daunting challenge because most of the boundary shear is exerted on immobile grains. We present an alternative approach that divides the bed into sand patches and interstitial deposits and is well constrained by two clear end-member cases: full sand cover and absence of sand. Entrainment from sand patches is a function of their aerial coverage. Entrainment from interstices among immobile grains is a function of sand elevation relative to the size of the immobile grains. The bed-sand coverage function is used to predict the ratio of the rate of entrainment from a partially covered bed to the rate of entrainment from a completely sand-covered bed, which is determined using a standard sand transport model. We implement the bed-sand coverage function in a morphodynamic routing model and test it against observations of sand bed elevation and suspended sand concentration for conditions of nonuniform fine sediment transport in a large flume with steady uniform flow over immobile hemispheres. The results suggest that this approach may provide a simple and robust method for predicting the transport and migration of fine sediment through rivers with coarse, immobile beds.

Design and control of the precise tracking bed based on complex electromechanical design theory

NASA Astrophysics Data System (ADS)

Ren, Changzhi; Liu, Zhao; Wu, Liao; Chen, Ken

2010-05-01

The precise tracking technology is wide used in astronomical instruments, satellite tracking and aeronautic test bed. However, the precise ultra low speed tracking drive system is one high integrated electromechanical system, which one complexly electromechanical design method is adopted to improve the efficiency, reliability and quality of the system during the design and manufacture circle. The precise Tracking Bed is one ultra-exact, ultra-low speed, high precision and huge inertial instrument, which some kind of mechanism and environment of the ultra low speed is different from general technology. This paper explores the design process based on complex electromechanical optimizing design theory, one non-PID with a CMAC forward feedback control method is used in the servo system of the precise tracking bed and some simulation results are discussed.

A fluidized bed desorption system for recycling mercury from contaminated soil

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

Harriss, C.; Baum, D.L. Jr.; Read, W.L.

1995-12-31

The land disposal restrictions effective for wastes containing mercury have created a need for technologies that can meet the best demonstrated available technologies (BDAT) treatment standards. In the past, technologies for mercury were in short supply. In addition to the already existing short supply, the natural gas industry has begun to remediate the numerous metering sites that have been contaminated with mercury from manometers installed along their pipelines. To meet the need for a mercury technology, Philip Environmental Services Corporation (Philip) evaluated and tested two different technologies capable of recovering mercury from contaminated soil. Philip initially performed some tests usingmore » gravitational methods followed by pilot-scale testing using a fluidized bed desorber. As a result of the testing, Philip constructed a full-scale fluidized bed system which can recover mercury from contaminated soil and debris. The name of Philip`s technology is the Solvating Vapor Pressure Process (SVPP). The main purpose of this paper is to discuss the results of the SVPP pilot testing and describe the process.« less

Brief notes on habitat geology and clay pipe habitat on Stellwagen Bank

USGS Publications Warehouse

Valentine, Page C.; Dorsey, Eleanor M.; Pederson, Judith

1998-01-01

In our studies of sea floor habitats, my colleagues and I use both biological and geological approaches. We call our studies “habitat geology,” a term coined by a biologist friend of mine. We view it as the study of sea floor materials and biological and geological processes that influence where species live. Some of the factors that we consider are the following:composition of the sea bed, which ranges from mud to sand, gravel, bedrock, and shell beds;shape and steepness of the bottom;roughness of the bottom, which is enhanced by the presence of cobbles, boulders, sand waves and ripples, burrows into the bottom, and species that extend above the bottom;bottom currents generated by storm waves and tides, which can move sediment and expose or cover habitats; andthe way in which the sea bed is utilized by species.In addition, we take into account the impact of sea bed disturbance by bottom fishing trawls and dredges. Habitats characterized by attached and burrowing species that protrude above the sea bed appear to be most vulnerable to disturbance.

Modelling and simulation of wood chip combustion in a hot air generator system.

PubMed

Rajika, J K A T; Narayana, Mahinsasa

2016-01-01

This study focuses on modelling and simulation of horizontal moving bed/grate wood chip combustor. A standalone finite volume based 2-D steady state Euler-Euler Computational Fluid Dynamics (CFD) model was developed for packed bed combustion. Packed bed combustion of a medium scale biomass combustor, which was retrofitted from wood log to wood chip feeding for Tea drying in Sri Lanka, was evaluated by a CFD simulation study. The model was validated by the experimental results of an industrial biomass combustor for a hot air generation system in tea industry. Open-source CFD tool; OpenFOAM was used to generate CFD model source code for the packed bed combustion and simulated along with an available solver for free board region modelling in the CFD tool. Height of the packed bed is about 20 cm and biomass particles are assumed to be spherical shape with constant surface area to volume ratio. Temperature measurements of the combustor are well agreed with simulation results while gas phase compositions have discrepancies. Combustion efficiency of the validated hot air generator is around 52.2 %.

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

Wheeler, P.A.; Patel, N.M.; Painter, A.

Energy recovery from municipal solid waste (MSW) is an important component of an integrated waste management strategy. Waste management programs which remove or recover materials for recycling are particularly suited for considering the option of energy recovery via fluidized bed combustion (FBC). The last few years have seen growing interest in the application of FBC technology to the MSW treatment/disposal problem. This paper reviews and reports on the world-wide experience in fluidized bed combustion of MSW focusing particularly on the types and scales of the systems in operation in Japan and Scandinavia. In addition the paper also reports on themore » development of an energy from waste project employing circulating fluidized bed technology that is proposed for a local municipality in the UK. Japan currently has over 100 bubbling bed units in operation firing on 100% MSW; the technology is firmly established at scales of operation up to 160,000t/y (the largest single unit operates at 6.25t/h). The bubbling bed units accept MSW which has undergone only minimal pre-processing -- the waste is shredded to a nominal 300mm size fraction before being introduced to the furnace. There are distinct (combustion control) advantages to further processing of the waste stream prior to combustion. The Scandinavian countries in particular have been the prime movers in pioneering this technology to work in combination with circulating fluidized bed systems. Currently 2 units are in operation cofiring pre-processed MSW with a range of other biofuels. A number of FBC units firing 100% MSW are currently in the planning or construction stage around the world; they seem set to secure an increased market share particularly at the smaller scale of operation (up to about 200,000t/y).« less

Design and Development Comparison of Rapid Cycle Amine 1.0, 2.0, and 3.0

NASA Technical Reports Server (NTRS)

Chullen, Cinda; Campbell, Colin; Papale, William; Murray, Sean; Wichowski, Robert; Conger, Bruce; McMillin, Summer

2016-01-01

The development of the Rapid Cycle Amine (RCA) swing-bed technology for carbon dioxide (CO2) removal has been in progress since favorable results were published in 1996. Shortly thereafter, a prototype was designed, developed, and tested successfully and delivered to Johnson Space Center in 1999. An improved prototype (RCA 1.0) was delivered to NASA in 2006 and sized for the extravehicular activity (EVA). The RCA swing-bed technology is a regenerative system which employs two alternating solid-amine sorbent beds to remove CO2 and water. The two-bed design employs a chemisorption process whereby the beds alternate between adsorption and desorption. This process provides for an efficient RCA operation that enables one bed to be in adsorb (uptake) mode, while the other is in the desorb (regeneration) mode. The RCA has progressed through several iterations of technology readiness levels. Test articles have now been designed, developed, and tested for the advanced space suit portable life support system (PLSS) including RCA 1.0, RCA 2.0, and RCA 3.0. The RCA 3.0 was the most recent RCA fabrication and was delivered to NASA-JSC in June 2015. The RCA 1.0 test article was designed with a pneumatically actuated linear motion spool valve. The RCA 2.0 and 3.0 test articles were designed with a valve assembly which allows for switching between uptake and regeneration modes while minimizing gas volume losses to the vacuum source. RCA 2.0 and 3.0 also include an embedded controller design to control RCA operation and provide the capability of interfacing with various sensors and other ventilation loop components. The RCA technology is low power, small, and has fulfilled all test requirements levied upon the technology during development testing thus far. This paper will provide an overview of the design and development of RCA 1.0, 2.0 and 3.0 including detail differences between the design specifications of each. Nomenclature.

Design and Development Comparison of Rapid Cycle Amine 1.0, 2.0, and 3.0

NASA Technical Reports Server (NTRS)

Chullen, Cinda; Campbell, Colin; Papale, William; Murray, Sean; Wichowski, Robert; Conger, Bruce; McMillin, Summer

2016-01-01

The development of the Rapid Cycle Amine (RCA) swing-bed technology for carbon dioxide (CO2) removal has been in progress since favorable results were published in 1996. Shortly thereafter, a prototype was designed, developed, and tested successfully and delivered to Johnson Space Center in 1999. An improved prototype was delivered to NASA in 2006 and was notated as RCA 1.0 and sized for the extravehicular activity (EVA). The new RCA swing-bed technology is a regenerative system which employs two alternating solid-amine sorbent beds to remove CO2 and water. The two- bed design employs a chemisorption process whereby the beds alternate between adsorbtion and desorbsion. This process provides for an efficient operation of the RCA so that while one bed is in adsorb (uptake) mode, the other is in the desorb (regeneration) mode. The RCA has now progressed through several iterations of technology readiness levels. Test articles have now been designed, developed, and tested for the advanced space suit portable life support system (PLSS) including RCA 1.0, RCA 2.0, and RCA 3.0. The RCA 3.0 was the most recent RCA fabrication and was delivered to NASA-JSC in June 2015. The RCA 1.0 test article was designed with a pneumatically actuated linear motion spool valve. The RCA 2.0 and 3.0 test articles were designed with a valve assembly which allows for switching between uptake and regeneration modes while minimizing gas volume losses to the vacuum source. RCA 2.0 and 3.0 also include an embedded controller design to control RCA operation and provide the capability of interfacing with various sensors and other ventilation loop components. The RCA technology is low power, small, and has fulfilled all test requirements levied upon the technology during development testing thus far. This paper will provide an overreview of the design and development of RCA 1.0, 2.0 and 3.0 including detail differences between the design specifications of each.

Advanced treatment of biologically pretreated coal gasification wastewater by a novel integration of heterogeneous Fenton oxidation and biological process.

PubMed

Xu, Peng; Han, Hongjun; Zhuang, Haifeng; Hou, Baolin; Jia, Shengyong; Xu, Chunyan; Wang, Dexin

2015-04-01

Laboratorial scale experiments were conducted in order to investigate a novel system integrating heterogeneous Fenton oxidation (HFO) with anoxic moving bed biofilm reactor (ANMBBR) and biological aerated filter (BAF) process on advanced treatment of biologically pretreated coal gasification wastewater (CGW). The results indicated that HFO with the prepared catalyst (FeOx/SBAC, sewage sludge based activated carbon (SBAC) which loaded Fe oxides) played a key role in eliminating COD and COLOR as well as in improving the biodegradability of raw wastewater. The surface reaction and hydroxyl radicals (OH) oxidation were the mechanisms for FeOx/SBAC catalytic reaction. Compared with ANMBBR-BAF process, the integrated system was more effective in abating COD, BOD5, total phenols (TPs), total nitrogen (TN) and COLOR and could shorten the retention time. Therefore, the integrated system was a promising technology for engineering applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

KSC-2012-4028

NASA Image and Video Library

2012-07-27

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, is moved into a building at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser

KSC-2012-4029

NASA Image and Video Library

2012-07-27

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, is moved into a building at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser

Will river erosion below the Three Gorges Dam stop in the middle Yangtze?

NASA Astrophysics Data System (ADS)

Lai, X.; Yin, D.; Finlayson, B. L.; Wei, T.; Li, M.; Yuan, W.; Yang, S.; Dai, Z.; Gao, S.; Chen, Z.

2017-11-01

The environmental impact of the Three Gorges Dam has been a subject of vigorous academic, political and social debate since its inception. This includes the key issue of post-dam river channel erosion, which was predicted by the feasibility study to extend to the river mouth. In this paper we examine the geomorphic response of the channel of the middle Yangtze for 660 km downstream of the dam. Using data on channel characteristics, bed material and sediment transport, we show that in the decade following the dam closure, pre-dam seasonal erosion has been replaced by year-round erosion, a pattern most marked at the upstream end of the study area. The sediment carrying capacity of the river channel has been largely reduced below the dam. The locus of bed scour has moved progressively downstream, ceasing as the bed material became too coarse to be transported (e.g. D50: 0.29 mm pre-dam coarsened to 20 mm below the dam by 2008). About 400 km below the dam there is a reduction in channel slope that changes the sediment carrying capacity from 0.25 kg m-3 to only about 0.05 kg m-3, which is insufficient to move bed sediment. The new long-term hydro-morphological equilibrium that will be established in this section of the middle Yangtze will prevent the further incision downstream initiated by the Three Gorges Dam. The results suggest that the full extent of adverse environmental impact predicted by the pre-dam studies will not eventuate.

Direct Reduction of Iron Ore

NASA Astrophysics Data System (ADS)

Small, M.

1981-04-01

In the search for a pure, available iron source, steelmakers are focusing their attention on Directly Reduced Iron (DRI). This material is produced by the reaction of a low gangue iron ore with a hydrocarbonaceous substance. Commercially, DRI is generated in four different reactors: shaft (moving-bed), rotary kiln, fluidized bed, and retort (fixed-bed). Annual worldwide production capacity approaches 33 million metric tons. Detailed assessments have been made of the uses of DRI, especially as a substitute for scrap in electric furnace (EF) steelmaking. DRI is generally of a quality superior to current grades of scrap, with steels produced more efficiently in the EF and containing lower levels of impurities. However, present economics favor EF steel production with scrap. But this situation could change within this decade because of a developing scarcity of good quality scrap.

The Importance of Splat Events to the Spatiotemporal Structure of Near-Bed Fluid Velocity and Bed Load Motion Over Bed Forms: Laboratory Experiments Downstream of a Backward Facing Step

NASA Astrophysics Data System (ADS)

Leary, K. C. P.; Schmeeckle, M. W.

2017-12-01

Flow separation/reattachment on the lee side of alluvial bed forms is known to produce a complex turbulence field, but the spatiotemporal details of the associated patterns of bed load sediment transported remain largely unknown. Here we report turbulence-resolving, simultaneous measurements of bed load motion and near-bed fluid velocity downstream of a backward facing step in a laboratory flume. Two synchronized high-speed video cameras simultaneously observed bed load motion and the motion of neutrally buoyant particles in a laser light sheet 6 mm above the bed at 250 frames/s downstream of a 3.8 cm backward facing step. Particle Imaging Velocimetry (PIV) and Acoustic Doppler Velocimetry (ADV) were used to characterize fluid turbulent patterns, while manual particle tracking techniques were used to characterize bed load transport. Octant analysis, conducted using ADV data, coupled with Markovian sequence probability analysis highlights differences in the flow near reattachment versus farther downstream. Near reattachment, three distinct flow patterns are apparent. Farther downstream we see the development of a dominant flow sequence. Localized, intermittent, high-magnitude transport events are more apparent near flow reattachment. These events are composed of streamwise and cross-stream fluxes of comparable magnitudes. Transport pattern and fluid velocity data are consistent with the existence of permeable "splat events," wherein a volume of fluid moves toward and impinges on the bed (sweep) causing a radial movement of fluid in all directions around the point of impingement (outward interaction). This is congruent with flow patterns, identified with octant analysis, proximal to flow reattachment.

High-Flux, High Performance H2O2 Catalyst Bed for ISTAR

NASA Technical Reports Server (NTRS)

Ponzo, J.

2005-01-01

On NASA's ISTAR RBCC program packaging and performance requirements exceeded traditional H2O2 catalyst bed capabilities. Aerojet refined a high performance, monolithic 90% H202 catalyst bed previously developed and demonstrated. This approach to catalyst bed design and fabrication was an enabling technology to the ISTAR tri-fluid engine. The catalyst bed demonstrated 55 starts at throughputs greater than 0.60 lbm/s/sq in for a duration of over 900 seconds in a physical envelope approximately 114 of traditional designs. The catalyst bed uses photoetched plates of metal bonded into a single piece monolithic structure. The precise control of the geometry and complete mixing results in repeatable, quick starting, high performing catalyst bed. Three different beds were designed and tested, with the best performing bed used for tri-fluid engine testing.

Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

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

Jantzen, C. M.; Pierce, E. M.; Bannochie, C. J.

This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Wastemore » and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.« less

Co-Production of Electricity and Hydrogen Using a Novel Iron-based Catalyst

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

Hilaly, Ahmad; Georgas, Adam; Leboreiro, Jose

2011-09-30

The primary objective of this project was to develop a hydrogen production technology for gasification applications based on a circulating fluid-bed reactor and an attrition resistant iron catalyst. The work towards achieving this objective consisted of three key activities: Development of an iron-based catalyst suitable for a circulating fluid-bed reactor; Design, construction, and operation of a bench-scale circulating fluid-bed reactor system for hydrogen production; Techno-economic analysis of the steam-iron and the pressure swing adsorption hydrogen production processes. This report describes the work completed in each of these activities during this project. The catalyst development and testing program prepared and iron-basedmore » catalysts using different support and promoters to identify catalysts that had sufficient activity for cyclic reduction with syngas and steam oxidation and attrition resistance to enable use in a circulating fluid-bed reactor system. The best performing catalyst from this catalyst development program was produced by a commercial catalyst toll manufacturer to support the bench-scale testing activities. The reactor testing systems used during material development evaluated catalysts in a single fluid-bed reactor by cycling between reduction with syngas and oxidation with steam. The prototype SIP reactor system (PSRS) consisted of two circulating fluid-bed reactors with the iron catalyst being transferred between the two reactors. This design enabled demonstration of the technical feasibility of the combination of the circulating fluid-bed reactor system and the iron-based catalyst for commercial hydrogen production. The specific activities associated with this bench-scale circulating fluid-bed reactor systems that were completed in this project included design, construction, commissioning, and operation. The experimental portion of this project focused on technical demonstration of the performance of an iron-based catalyst and a circulating fluid-bed reactor system for hydrogen production. Although a technology can be technically feasible, successful commercial deployment also requires that a technology offer an economic advantage over existing commercial technologies. To effective estimate the economics of this steam-iron process, a techno-economic analysis of this steam iron process and a commercial pressure swing adsorption process were completed. The results from this analysis described in this report show the economic potential of the steam iron process for integration with a gasification plant for coproduction of hydrogen and electricity.« less

Development of a High-Fidelity Simulation Environment for Shadow-Mode Assessments of Air Traffic Concepts

NASA Technical Reports Server (NTRS)

Robinson, John E., III; Lee, Alan; Lai, Chok Fung

2017-01-01

This paper describes the Shadow-Mode Assessment Using Realistic Technologies for the National Airspace System (SMART-NAS) Test Bed. The SMART-NAS Test Bed is an air traffic simulation platform being developed by the National Aeronautics and Space Administration (NASA). The SMART-NAS Test Bed's core purpose is to conduct high-fidelity, real-time, human-in-the-loop and automation-in-the-loop simulations of current and proposed future air traffic concepts for the United States' Next Generation Air Transportation System called NextGen. The setup, configuration, coordination, and execution of realtime, human-in-the-loop air traffic management simulations are complex, tedious, time intensive, and expensive. The SMART-NAS Test Bed framework is an alternative to the current approach and will provide services throughout the simulation workflow pipeline to help alleviate these shortcomings. The principle concepts to be simulated include advanced gate-to-gate, trajectory-based operations, widespread integration of novel aircraft such as unmanned vehicles, and real-time safety assurance technologies to enable autonomous operations. To make this possible, SNTB will utilize Web-based technologies, cloud resources, and real-time, scalable, communication middleware. This paper describes the SMART-NAS Test Bed's vision, purpose, its concept of use, and the potential benefits, key capabilities, high-level requirements, architecture, software design, and usage.

Achieving nitritation in a continuous moving bed biofilm reactor at different temperatures through ratio control.

PubMed

Bian, Wei; Zhang, Shuyan; Zhang, Yanzhuo; Li, Wenjing; Kan, Ruizhe; Wang, Wenxiao; Zheng, Zhaoming; Li, Jun

2017-02-01

A ratio control strategy was implemented in a continuous moving bed biofilm reactor (MBBR) to investigate the response to different temperatures. The control strategy was designed to maintain a constant ratio between dissolved oxygen (DO) and total ammonia nitrogen (TAN) concentrations. The results revealed that a stable nitritation in a biofilm reactor could be achieved via ratio control, which compensated the negative influence of low temperatures by stronger oxygen-limiting conditions. Even with a temperature as low as 6°C, stable nitritation could be achieved when the controlling ratio did not exceed 0.17. Oxygen-limiting conditions in the biofilm reactor were determined by the DO/TAN concentrations ratio, instead of the mere DO concentration. This ratio control strategy allowed the achievement of stable nitritation without complete wash-out of NOB from the reactor. Through the ratio control strategy full nitritation of sidestream wastewater was allowed; however, for mainstream wastewater, only partial nitritation was recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of carrier filling ratio on the performance of moving bed biofilm reactor in treating coking wastewater.

PubMed

Gu, Qiyuan; Sun, Tichang; Wu, Gen; Li, Mingyue; Qiu, Wei

2014-08-01

This study aims to evaluate the effect of carrier filling ratio on the performance of a moving bed biofilm reactor in degrading chemical oxygen demand, phenol, thiocyanate, and ammonia from coking wastewater at 20h of hydraulic retention time. The operational experiments under different carrier filling ratios ranging from 20% to 60% were investigated. The maximum removal efficiency of 89%, 99% and 99% for COD, phenol and thiocyanate, and minimum sensitivity to the increasing contaminants concentration in the influent were achieved at 50% carrier filling ratio. The Haldane competitive substrate inhibition kinetics model was used to describe the relationship between the oxygen uptake rate of ammonium oxidizers and the concentration of free ammonium. The highest biofilm microbial community functional diversity (Shannon's diversity index, H') and evenness (Shannon's evenness index, E') were obtained at 50% carrier filling ratio in all runs using a Biolog ECO microplate. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of bacterial structures in two-stage moving-bed biofilm reactor (MBBR) during nitrification of the landfill leachate.

PubMed

Ciesielski, Slawomir; Kulikowska, Dorota; Kaczowka, Ewelina; Kowal, Przemysław

2010-07-01

Differences in DNA banding patterns, obtained by ribosomal intergenic spacer analysis (RISA), and nitrification were followed in a moving-bed biofilm reactor (MBBR) receiving municipal landfill leachate. Complete nitrification (> 99%) to nitrate was obtained in the two-stage MBBR system with an ammonium load of 1.09 g N-NH(4)/m(2).d. Increasing the ammonium load to 2.03 g N-NH(4)/m(2).d or more caused a decline in process efficiency to 70-86%. Moreover, at the highest ammonium load (3.76 g N-NH(4)/m(2).d), nitrite was the predominant product of nitrification. Community succession was evident in both compartments in response to changes in ammonium load. Non-metric multidimensional scaling (NMDS) supported by similarity analysis (ANOSIM) showed that microbial biofilm communities differed between compartments. The microbial biofilm was composed mainly of ammonia-oxidizing bacteria (AOB), with Nitrosomonas europeae and N. eutropha being most abundant. These results suggest that high ammonium concentrations select for particular AOB strains.

Prediction of moving bed biofilm reactor (MBBR) performance for the treatment of aniline using artificial neural networks (ANN).

PubMed

Delnavaz, M; Ayati, B; Ganjidoust, H

2010-07-15

In this study, the results of 1-year efficiency forecasting using artificial neural networks (ANN) models of a moving bed biofilm reactor (MBBR) for a toxic and hard biodegradable aniline removal were investigated. The reactor was operated in an aerobic batch and continuous condition with 50% by volume which was filled with light expanded clay aggregate (LECA) as carrier. Efficiency evaluation of the reactors was obtained at different retention time (RT) of 8, 24, 48 and 72 h with an influent COD from 100 to 4000 mg/L. Exploratory data analysis was used to detect relationships between the data and dependent evaluated one. The appropriate architecture of the neural network models was determined using several steps of training and testing of the models. The ANN-based models were found to provide an efficient and a robust tool in predicting MBBR performance for treating aromatic amine compounds. 2010 Elsevier B.V. All rights reserved.

Removal of pharmaceuticals in conventionally treated wastewater by a polishing moving bed biofilm reactor (MBBR) with intermittent feeding.

PubMed

Tang, Kai; Ooi, Gordon T H; Litty, Klaus; Sundmark, Kim; Kaarsholm, Kamilla M S; Sund, Christina; Kragelund, Caroline; Christensson, Magnus; Bester, Kai; Andersen, Henrik R

2017-07-01

Previous studies have demonstrated that aerobic moving bed biofilm reactors (MBBRs) remove pharmaceuticals better than activated sludge. Thus we used a MBBR system to polish the effluent of an activated sludge wastewater treatment plant. To overcome that effluent contains insufficient organic matter to sustain enough biomass, the biofilm was intermittently fed with raw wastewater. The capacity of pharmaceutical degradation was investigated by spiking pharmaceuticals. Actual removal during treatment was assessed by sampling the inlets and outlets of reactors. The removal of the majority of pharmaceuticals was enhanced through the intermittent feeding of the MBBR. First-order rate constants for pharmaceutical removal, normalised to biomass, were significantly higher compared to other studies on activated sludge and suspended biofilms, especially for diclofenac, metoprolol and atenolol. Due to the intermittently feeding, degradation of diclofenac occurred with a half-life of only 2.1h and was thus much faster than any hitherto described wastewater bioreactor treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

New functional biocarriers for enhancing the performance of a hybrid moving bed biofilm reactor-membrane bioreactor system.

PubMed

Deng, Lijuan; Guo, Wenshan; Ngo, Huu Hao; Zhang, Xinbo; Wang, Xiaochang C; Zhang, Qionghua; Chen, Rong

2016-05-01

In this study, new sponge modified plastic carriers for moving bed biofilm reactor (MBBR) was developed. The performance and membrane fouling behavior of a hybrid MBBR-membrane bioreactor (MBBR-MBR) system were also evaluated. Comparing to the MBBR with plastic carriers (MBBR), the MBBR with sponge modified biocarriers (S-MBBR) showed better effluent quality and enhanced nutrient removal at HRTs of 12h and 6h. Regarding fouling issue of the hybrid systems, soluble microbial products (SMP) of the MBR unit greatly influenced membrane fouling. The sponge modified biocarriers could lower the levels of SMP in mixed liquor and extracellular polymeric substances in activated sludge, thereby mitigating cake layer and pore blocking resistances of the membrane. The reduced SMP and biopolymer clusters in membrane cake layer were also observed. The results demonstrated that the sponge modified biocarriers were capable of improving overall MBBR performance and substantially alleviated membrane fouling of the subsequent MBR unit. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combination of upflow anaerobic sludge blanket (UASB) reactor and partial nitritation/anammox moving bed biofilm reactor (MBBR) for municipal wastewater treatment.

PubMed

Malovanyy, Andriy; Yang, Jingjing; Trela, Jozef; Plaza, Elzbieta

2015-03-01

In this study the combination of an upflow anaerobic sludge blanket (UASB) reactor and a deammonification moving bed biofilm reactor (MBBR) for mainstream wastewater treatment was tested. The competition between aerobic ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) was studied during a 5months period of transition from reject water to mainstream wastewater followed by a 16months period of mainstream wastewater treatment. The decrease of influent ammonium concentration led to a wash-out of suspended biomass which had a major contribution to nitrite production. Influence of a dissolved oxygen concentration and a transient anoxia mechanism of NOB suppression were studied. It was shown that anoxic phase duration has no effect on NOB metabolism recovery and oxygen diffusion rather than affinities of AOB and NOB to oxygen determine the rate of nitrogen conversion in a biofilm system. Anammox activity remained on the level comparable to reject water treatment systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative analysis of the bacterial diversity in a lab-scale moving bed biofilm reactor (MBBR) applied to treat urban wastewater under different operational conditions.

PubMed

Calderón, Kadiya; Martín-Pascual, Jaime; Poyatos, José Manuel; Rodelas, Belén; González-Martínez, Alejandro; González-López, Jesús

2012-10-01

Different types of carriers were tested as support material in a lab-scale moving bed biofilm reactor (MBBR) used to treat urban wastewater under three different conditions of hydraulic retention time (HRT) and carrier filling ratios (FR). The bacterial diversity developed on the biofilms responsible of the treatment was studied using a cultivation-independent approach based on the polymerase chain reaction-temperature gradient gel electrophoresis technique (PCR-TGGE). Cluster analysis of TGGE fingerprints showed significant differences of community structure dependent upon the different operational conditions applied. Redundancy analysis (RDA) was used to determine the relationship between the operational conditions (type of carrier, HRT, FR) and bacterial biofilm diversity, demonstrating a significant effect of FR=50%. Phylogenetic analysis of PCR-reamplified and sequenced TGGE bands revealed that the prevalent Bacteria populations in the biofilm were related to Betaproteobacteria (46%), Firmicutes (34%),Alphaproteobacteria (14%) and Gammaproteobacteria (9%). Copyright © 2012 Elsevier Ltd. All rights reserved.

Utilization of moving bed biofilm reactor for industrial wastewater treatment containing ethylene glycol: kinetic and performance study.

PubMed

Hassani, Amir Hessam; Borghei, Seyed Mehdi; Samadyar, Hassan; Ghanbari, Bastam

2014-01-01

One of the requirements for environmental engineering, which is currently being considered, is the removal of ethylene glycol (EG) as a hazardous environmental pollutant from industrial wastewater. Therefore, in a recent study, a moving bed biofilm reactor (MBBR) was applied at pilot scale to treat industrial effluents containing different concentrations of EG (600, 800, 1200, and 1800 mg L-1 ). The removal efficiency and kinetic analysis of the system were examined at different hydraulic retention times of 6, 8, 10, and 12 h as well as influent chemical oxygen demand (COD) ranged between values of 1000 and 3000mg L-1. In minimum and maximum COD Loadings, the MBBR showed 95.1% and 60.7% removal efficiencies, while 95.9% and 66.2% EG removal efficiencies were achieved in the lowest and highest EG concentrations. The results of the reactor modelling suggested compliance of the well-known modified Stover-Kincannon model with the system.

High-rate wastewater treatment combining a moving bed biofilm reactor and enhanced particle separation.

PubMed

Helness, H; Melin, E; Ulgenes, Y; Järvinen, P; Rasmussen, V; Odegaard, H

2005-01-01

Many cities around the world are looking for compact wastewater treatment alternatives since space for treatment plants is becoming scarce. In this paper development of a new compact, high-rate treatment concept with results from experiments in lab-scale and pilot-scale are presented. The idea behind the treatment concept is that coagulation/floc separation may be used to separate suspended and colloidal matter (resulting in > 70% organic matter removal in normal wastewater) while a high-rate biofilm process (based on Moving Bed biofilm reactors) may be used for removing low molecular weight, easily biodegradable, soluble organic matter. By using flotation for floc/biomass separation, the total residence time for a plant according to this concept will normally be < 1 hour. A cationic polymer combined with iron is used as coagulant at low dosages (i.e. 1-2 mg polymer/l, 5-10 mg Fe/l) resulting in low sludge production (compared to conventional chemical treatment) and sufficient P-removal.

Treatment of oilfield wastewater in moving bed biofilm reactors using a novel suspended ceramic biocarrier.

PubMed

Dong, Zhiyong; Lu, Mang; Huang, Wenhui; Xu, Xiaochun

2011-11-30

In this study, a novel suspended ceramic carrier was prepared, which has high strength, optimum density (close to water), and high porosity. Two different carriers, unmodified and sepiolite-modified suspended ceramic carriers were used to feed two moving bed biofilm reactors (MBBRs) with a filling fraction of 50% to treat oilfield produced water. The hydraulic retention time (HRT) was varied from 36 to 10h. The results, during a monitoring period of 190 days, showed that removal efficiency of chemical oxygen demand was the highest in reactor 3 filled with the sepiolite-modified carriers, followed by reactor 2 filled with the unmodified carriers, with the lowest in reactor 1 (activated sludge reactor), at an HRT of 10h. Similar trends were found in the removal efficiencies of ammonia nitrogen and polycyclic aromatic hydrocarbons. Reactor 3 was more shock resistant than reactors 2 and 1. The results indicate that the suspended ceramic carrier is an excellent MBBR carrier. Copyright © 2011 Elsevier B.V. All rights reserved.

Removal and fate of micropollutants in a sponge-based moving bed bioreactor.

PubMed

Luo, Yunlong; Guo, Wenshan; Ngo, Huu Hao; Nghiem, Long Duc; Hai, Faisal Ibney; Kang, Jinguo; Xia, Siqing; Zhang, Zhiqiang; Price, William Evan

2014-05-01

This study investigated the removal of micropollutants using polyurethane sponge as attached-growth carrier. Batch experiments demonstrated that micropollutants could adsorb to non-acclimatized sponge cubes to varying extents. Acclimatized sponge showed significantly enhanced removal of some less hydrophobic compounds (log D<2.5), such as ibuprofen, acetaminophen, naproxen, and estriol, as compared with non-acclimatized sponge. The results for bench-scale sponge-based moving bed bioreactor (MBBR) system elucidated compound-specific variation in removal, ranging from 25.9% (carbamazepine) to 96.8% (β-Estradiol 17-acetate) on average. In the MBBR system, biodegradation served as a major removal pathway for most compounds. However, sorption to sludge phase was also a notable removal mechanism of some persistent micropollutants. Particularly, carbamazepine, ketoprofen and pentachlorophenol were found at high concentrations (7.87, 6.05 and 5.55 μg/g, respectively) on suspended biosolids. As a whole, the effectiveness of MBBR for micropollutant removal was comparable with those of activated sludge processes and MBRs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of C/N shock variation on the performances of a moving bed membrane bioreactor.

PubMed

Di Trapani, Daniele; Di Bella, Gaetano; Mannina, Giorgio; Torregrossa, Michele; Viviani, Gaspare

2015-08-01

The effect of a sharp variation of C/N ratio in a moving bed membrane bioreactor (MB-MBR) pilot plant treating high strength wastewater has been investigated. The experimental campaign was divided into two periods, each characterized by a different C/N ratio (namely, 2.5 and 15, Period 1 and Period 2, respectively). The MB-MBR system was analyzed in terms of organic carbon removal, nitrification efficiency, biokinetic activity and fouling behavior. The results showed that the nitrification process was severely affected by lower C/N value and by high concentration of ammonia. It was noticed an extensive stress effect on the autotrophic bacteria. Furthermore, it was observed an increase of the resistance related to particle deposition into membrane pores, likely due to a worsening of the cake layer features, with a reduction of the "pre-filter" effect, also related to the increase of the total Extracellular Polymeric Substances production with the C/N ratio. Copyright © 2015 Elsevier Ltd. All rights reserved.

Screening selectively harnessed environmental microbial communities for biodegradation of polycyclic aromatic hydrocarbons in moving bed biofilm reactors.

PubMed

Demeter, Marc A; Lemire, Joseph A; Mercer, Sean M; Turner, Raymond J

2017-03-01

Bacteria are often found tolerating polluted environments. Such bacteria may be exploited to bioremediate contaminants in controlled ex situ reactor systems. One potential strategic goal of such systems is to harness microbes directly from the environment such that they exhibit the capacity to markedly degrade organic pollutants of interest. Here, the use of biofilm cultivation techniques to inoculate and activate moving bed biofilm reactor (MBBR) systems for the degradation of polycyclic aromatic hydrocarbons (PAHs) was explored. Biofilms were cultivated from 4 different hydrocarbon contaminated sites using a minimal medium spiked with the 16 EPA identified PAHs. Overall, all 4 inoculant sources resulted in biofilm communities capable of tolerating the presence of PAHs, but only 2 of these exhibited enhanced PAH catabolic gene prevalence coupled with significant degradation of select PAH compounds. Comparisons between inoculant sources highlighted the dependence of this method on appropriate inoculant screening and biostimulation efforts. Copyright © 2016 Elsevier Ltd. All rights reserved.

Demonstration of a 1 MWe biomass power plant at USMC Base Camp Lejeune. Report for July 1994-May 1997

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

Cleland, J.; Purvis, C.R.

1998-06-01

The paper discusses a biomass energy conversion project being sponsored by EPA to demonstrate an enviromentally and economically sound electrical power option for government installations, industrial sites, rural cooperatives, small municipalities, and developing countries. Wood gasification combined with internal combustion engines was chosen because of (1) recent improvements in gas cleaning, (2) simple economical operation for units < 10 MW, and (3) the option of a clean cheap fuel for the many existing facilities generating expensive electricity from petroleum fuels with reciprocating engines. The plant incorporates a downdraft, moving-bed gasifier utilizing hogged waste wood from the Marine Corps Base atmore » Camp Lejeune, NC. A moving-bed bulk wood dryer and both spark ignition and diesel engines are included. Unique process design features are described briefly, relative to the gasifier, wood drying, tar separation, and process control. A test plan for process optimization and demonstration of reliability, economics, and environmental impact is outlined.« less

The characteristics of extracellular polymeric substances and soluble microbial products in moving bed biofilm reactor-membrane bioreactor.

PubMed

Duan, Liang; Jiang, Wei; Song, Yonghui; Xia, Siqing; Hermanowicz, Slawomir W

2013-11-01

The characteristics of extracellular polymeric substances (EPS) and soluble microbial products (SMP) in conventional membrane bioreactor (MBR) and in moving bed biofilm reactor-membrane bioreactors (MBBR-MBR) were investigated in long-term (170 days) experiments. The results showed that all reactors had high removal efficiency of ammonium and COD, despite very different fouling conditions. The MBBR-MBR with media fill ratio of 26.7% had much lower total membrane resistance and no obvious fouling were detected during the whole operation. In contrast, MBR and MBBR-MBR with lower and higher media fill experienced more significant fouling. Low fouling at optimum fill ratio may be due to the higher percentage of small molecular size (<1 kDa) and lower percentage of large molecular size (>100 kDa) of EPS and SMP in the reactor. The composition of EPS and SMP affected fouling due to different O-H bonds in hydroxyl functional groups, and less polysaccharides and lipids. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optimization of startup and shutdown operation of simulated moving bed chromatographic processes.

PubMed

Li, Suzhou; Kawajiri, Yoshiaki; Raisch, Jörg; Seidel-Morgenstern, Andreas

2011-06-24

This paper presents new multistage optimal startup and shutdown strategies for simulated moving bed (SMB) chromatographic processes. The proposed concept allows to adjust transient operating conditions stage-wise, and provides capability to improve transient performance and to fulfill product quality specifications simultaneously. A specially tailored decomposition algorithm is developed to ensure computational tractability of the resulting dynamic optimization problems. By examining the transient operation of a literature separation example characterized by nonlinear competitive isotherm, the feasibility of the solution approach is demonstrated, and the performance of the conventional and multistage optimal transient regimes is evaluated systematically. The quantitative results clearly show that the optimal operating policies not only allow to significantly reduce both duration of the transient phase and desorbent consumption, but also enable on-spec production even during startup and shutdown periods. With the aid of the developed transient procedures, short-term separation campaigns with small batch sizes can be performed more flexibly and efficiently by SMB chromatography. Copyright © 2011 Elsevier B.V. All rights reserved.

Coking properties of coal under pressure and their influence on moving-bed gasification. Final report

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

Lancet, M.S.; Curran, G.P.; Sim, F.A.

1982-08-01

The coking properties of seven bituminous coals, including three Eastern US coals, one Midwestern US coal, a Western US coal and two from the UK were studied with respect to the possible utilization of these coals in moving bed gasifier systems. Complete physical, chemical and petrographic analyses were obtained for each coal in addition to the highly specialized CCDC simulated gasifier coking test data. The effects of total pressure, hydrogen partial pressure, heating rate and the addition of gob and tar on the fluidity and swelling properties of each coal was studied. Samples of each coal were shock heated undermore » pressure to simulate coking in the top of a Lurgi gasifier. The resultant cokes were tested for various physical properties and the product yields were determined. Gas release patterns during pressurized pyrolysis were obtained in several instances. The data obtained in this work should provide a valuable data base for future gasifier feedstock evaluation programs.« less

Catalyst Development for Hydrogen Peroxide Rocket Engines

NASA Technical Reports Server (NTRS)

Morlan, P. W.; Wu, P.-K.; Ruttle, D. W.; Fuller, R. P.; Nejad, A. S.; Anderson, W. E.

1999-01-01

The development of various catalysts of hydrogen peroxide was conducted for the applications of liquid rocket engines. The catalyst development includes silver screen technology, solid catalyst technology, and homogeneous catalyst technology. The silver screen technology development was performed with 85% (by weight) hydrogen peroxide. The results of this investigation were used as the basis for the catalyst design of a pressure-fed liquid-fueled upper stage engine. Both silver-plated nickel 200 screens and pure silver screens were used as the active metal catalyst during the investigation, The data indicate that a high decomposition efficiency (greater than 90%) of 85% hydrogen peroxide can be achieved at a bed loading of 0.5 lbm/sq in/sec with both pure silver and silver plated screens. Samarium oxide coating, however, was found to retard the decomposition process and the catalyst bed was flooded at lower bed loading. A throughput of 200 lbm of hydrogen peroxide (1000 second run time) was tested to evaluate the catalyst aging issue and performance degradation was observed starting at approximately 400 seconds. Catalyst beds of 3.5 inch in diameter was fabricated using the same configuration for a 1,000-lbf rocket engine. High decomposition efficiency was obtained with a low pressure drop across the bed. Solid catalyst using precious metal was also developed for the decomposition of hydrogen peroxide from 85% to 98% by weight. Preliminary results show that the catalyst has a strong reactivity even after 15 minutes of peroxide decomposition. The development effort also includes the homogeneous catalyst technology. Various non-toxic catalysts were evaluated with 98% peroxide and hydrocarbon fuels. The results of open cup drop tests indicate an ignition delay around 11 ms.

Mathematical modelling of particle mixing effect on the combustion of municipal solid wastes in a packed-bed furnace.

PubMed

Yang, Yao Bin; Swithenbank, Jim

2008-01-01

Packed bed combustion is still the most common way to burn municipal solid wastes. In this paper, a dispersion model for particle mixing, mainly caused by the movement of the grate in a moving-burning bed, has been proposed and transport equations for the continuity, momentum, species, and energy conservation are described. Particle-mixing coefficients obtained from model tests range from 2.0x10(-6) to 3.0x10(-5)m2/s. A numerical solution is sought to simulate the combustion behaviour of a full-scale 12-tonne-per-h waste incineration furnace at different levels of bed mixing. It is found that an increase in mixing causes a slight delay in the bed ignition but greatly enhances the combustion processes during the main combustion period in the bed. A medium-level mixing produces a combustion profile that is positioned more at the central part of the combustion chamber, and any leftover combustible gases (mainly CO) enter directly into the most intensive turbulence area created by the opposing secondary-air jets and thus are consumed quickly. Generally, the specific arrangement of the impinging secondary-air jets dumps most of the non-uniformity in temperature and CO into the gas flow coming from the bed-top, while medium-level mixing results in the lowest CO emission at the furnace exit and the highest combustion efficiency in the bed.

[Special beds. Pulmonary therapy system].

PubMed

Calixto Rodríguez, Joaquín; Rodríguez Martínez, Xavier; Marín i Vivó, Gemma; Paunellas Albert, Josep

2008-10-01

To be bedridden reduces one's capacity to move and produces muscular debility that affects the respiratory system leading to a decreased effectiveness in expectoration, the ability to spit up sputum. The pulmonary therapy system integrated in a bed is the result of applying motorized elements to the articulation points of the bad in order to achieve safe positions at therapeutic angles, which improve the breathing-perfusion (blood flow) relationship. This system also makes it possible to apply vibration waves to the patient which favor the elimination of bronchial-pulmonary secretions, the rehabilitation of the bedridden patient and decrease the work load for nursing personnel.

The WCSAR telerobotics test bed

NASA Technical Reports Server (NTRS)

Duffie, N.; Zik, J.; Teeter, R.; Crabb, T.

1988-01-01

Component technologies for use in telerobotic systems for space are being developed. As part of this effort, a test bed was established in which these technologies can be verified and integrated into telerobotic systems. The facility consists of two slave industrial robots, an articulated master arm controller, a cartesian coordinate master arm controller, and a variety of sensors, displays and stimulators for feedback to human operators. The controller of one of the slave robots remains in its commercial state, while the controller of the other robot has been replaced with a new controller that achieves high-performance in telerobotic operating modes. A dexterous slave hand which consists of two fingers and a thumb is being developed, along with a number of force-reflecting and non-force reflecting master hands, wrists and arms. A tactile sensing finger tip based on piezo-film technology has been developed, along with tactile stimulators and CAD-based displays for sensory feedback and sensory substitution. The telerobotics test bed and its component technologies are described, as well as the integration of these component technologies into telerobotic systems, and their performance in conjunction with human operators.

Positive train control test bed interoperability upgrades.

DOT National Transportation Integrated Search

2013-02-01

Transportation Technology Center, Inc. (TTCI) upgraded the Positive Train Control (PTC) Test Bed to support additional PTC testing configurations under Federal Railroad Administration (FRA) Task Order 270. The scope of work provided additional PTC Co...

Twelfth annual fluidized bed conference

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

NONE

1996-12-31

The Proceedings of the Twelfth Annual Fluidized Bed Conference held November 11-13, 1996 in Pittsburgh, PA are presented. Information is given on: owner`s discussions; new aspects and field upgrades in fluidized bed boilers; manufacturer`s perspectives; fuel considerations; FBC ash reclassification; and beneficial uses of FBC ash. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

Automation of the space station core module power management and distribution system

NASA Technical Reports Server (NTRS)

Weeks, David J.

1988-01-01

Under the Advanced Development Program for Space Station, Marshall Space Flight Center has been developing advanced automation applications for the Power Management and Distribution (PMAD) system inside the Space Station modules for the past three years. The Space Station Module Power Management and Distribution System (SSM/PMAD) test bed features three artificial intelligence (AI) systems coupled with conventional automation software functioning in an autonomous or closed-loop fashion. The AI systems in the test bed include a baseline scheduler/dynamic rescheduler (LES), a load shedding management system (LPLMS), and a fault recovery and management expert system (FRAMES). This test bed will be part of the NASA Systems Autonomy Demonstration for 1990 featuring cooperating expert systems in various Space Station subsystem test beds. It is concluded that advanced automation technology involving AI approaches is sufficiently mature to begin applying the technology to current and planned spacecraft applications including the Space Station.

Sludge dewatering and stabilization in drying reed beds: characterization of three full-scale systems in Catalonia, Spain.

PubMed

Uggetti, Enrica; Llorens, Esther; Pedescoll, Anna; Ferrer, Ivet; Castellnou, Roger; García, Joan

2009-09-01

Optimization of sludge management can help reducing sludge handling costs in wastewater treatment plants. Sludge drying reed beds appear as a new and alternative technology which has low energy requirements, reduced operating and maintenance costs, and causes little environmental impact. The objective of this work was to evaluate the efficiency of three full-scale drying reed beds in terms of sludge dewatering, stabilization and hygienisation. Samples of influent sludge and sludge accumulated in the reed beds were analysed for pH, Electrical Conductivity, Total Solids (TS), Volatile Solids (VS), Chemical Oxygen Demand, Biochemical Oxygen Demand, nutrients (Total Kjeldahl Nitrogen (TKN) and Total Phosphorus (TP)), heavy metals and faecal bacteria indicators (Escherichiacoli and Salmonella spp.). Lixiviate samples were also collected. There was a systematic increase in the TS concentration from 1-3% in the influent to 20-30% in the beds, which fits in the range obtained with conventional dewatering technologies. Progressive organic matter removal and sludge stabilization in the beds was also observed (VS concentration decreased from 52-67% TS in the influent to 31-49% TS in the beds). Concentration of nutrients of the sludge accumulated in the beds was quite low (TKN 2-7% TS and TP 0.04-0.7% TS), and heavy metals remained below law threshold concentrations. Salmonella spp. was not detected in any of the samples, while E. coli concentration was generally lower than 460MPN/g in the sludge accumulated in the beds. The studied systems demonstrated a good efficiency for sludge dewatering and stabilization in the context of small remote wastewater treatment plants.

Hydrologic characteristics and possible effects of surface mining in the northwestern part of West Branch Antelope Creek basin, Mercer County, North Dakota

USGS Publications Warehouse

Crawley, Mark E.; Emerson, Douglas G.

1981-01-01

Lignite beds and abundant discontinuous sandstone beds of the Paleocene Sentinel Butte Member of the Fort Union Formation and sand and gravel beds in the Quarternary glaciofluvial deposits (Antelope Creek aquifer) are the most important aquifers for domestic and livestock water supplies in the West Branch Antelope Creek basin. In the Beulah-Zap lignite, ground water moves from highland area in the west toward the Antelope Creek aquifer. Water levels in the basal Sentinel Butte sandstone appear to be controlled by the level of Lake Sakakawea. In the glaciofluvial deposits of the Antelope Creek aquifer water moves from a ground-water divide northwestward to Lake Sakakawea and southeastward toward the Knife River. Large water-level declines in wells completed in the lignite and shallower aquifers could be expected with mining. The effects probably would be limited to within 1 to 2 miles of an active mine. Surface-runoff duration could be altered by increased infiltration and retention in the reclaimed are and possible temporal extension of base flow could occur. Shallow ground water beneath mine sites would be expected to increase in dissolved solids and locally to contain large sodium and sulfate concentrations. In some locations movement of poor quality water toward the Antelope Creek aquifer would be expected. (USGS)

Pyroclast/snow interactions and thermally driven slurry formation. Part 1: Theory for monodisperse grain beds

USGS Publications Warehouse

Walder, J.S.

2000-01-01

Lahars are often produced as pyroclastic flows move over snow. This phenomenon involves a complicated interplay of mechanical and thermal processes that need to be separated to get at the fundamental physics. The thermal physics of pyroclast/snow interactions form the focus of this paper. A theoretical model is developed of heat- and mass transfer at the interface between a layer of uniformly sized pyroclasts and an underlying bed of snow, for the case in which there is no relative shear motion between pyroclasts and snow. A microscale view of the interface is required to properly specify boundary conditions. The physical model leads to the prediction that the upward flux of water vapor - which depends upon emplacement temperature, pyroclast grain size, pyroclast-layer thickness, and snow permeability - is sometimes sufficient to fluidize the pyroclasts. Uniform fluidization is usually unstable to bubble formation, which leads to vigorous convection of the pyroclasts themselves. Thus, predicted threshold conditions for fluidization are tantamount to predicted thresholds for particle convection. Such predictions are quantitatively in good agreement with results of experiments described in part 2 of this paper. Because particle convection commonly causes scour of the snow bed and transformation of the pyroclast layer to a slurry, there exists a 'thermal scour' process for generating lahars from pyroclastic flows moving over snow regardless of the possible role of mechanical scour.

Software and Hardware System for Fast Processes Study When Preparing Foundation Beds of Oil and Gas Facilities

NASA Astrophysics Data System (ADS)

Gruzin, A. V.; Gruzin, V. V.; Shalay, V. V.

2018-04-01

Analysis of existing technologies for preparing foundation beds of oil and gas buildings and structures has revealed the lack of reasoned recommendations on the selection of rational technical and technological parameters of compaction. To study the nature of the dynamics of fast processes during compaction of foundation beds of oil and gas facilities, a specialized software and hardware system was developed. The method of calculating the basic technical parameters of the equipment for recording fast processes is presented, as well as the algorithm for processing the experimental data. The performed preliminary studies confirmed the accuracy of the decisions made and the calculations performed.

[Applied study of the submerged macrophytes bed-immobilized bacteria in drinking water restoration].

PubMed

Chen, Qi-Chun; Li, Zheng-Kui; Wang, Yi-Chao; Wu, Kai; Fan, Nian-Wen

2012-01-01

The effect of submerged macrophytes bed-immobilized bacteria technology which applied in drinking water restoration was studied. Ammonifying bacteria, nitrobacteria, nitrosobacteria and denitrifying bacteria which isolated from Taihu Labe was immobilized to the porous carries, combined with the submerged macrophytes bed technology, we applied the new equipment in water restoration of gonghu bay, this equipment has good ability to resist storm, the denitrifying bacteria number increased from 5.4 x 10(2)-2.7 x 10(3) to 3.9 x 10(5)-9.1 x 10(5), N2O flux of experimental plot was 3-24 microg x (m2 x h)(-1), it's more than the contrast group obviously, TN concentration reduced 19% - 74%, while NO3- concentration reduced 24% -81% after the equipment running a period of time; The experimental data of 120 days showed that this technology is suitable for drinking water restoration, as it can control eutrophication.

Unmanned Instrument Platform for Undersea Exploration

NASA Technical Reports Server (NTRS)

Paine, G.; Hansen, G. R.; Gulizia, R. W.; Paluzzi, P.

1984-01-01

Instruments accommodated on moving underwater platform. Towable underwater platform 3.2 meters long, 1.2 meters wide, 1.4 meters high and has mass of about 1,250 kilogram. Platform remotely operated and unmanned. Serves as test bed for development of ocean-measuring instruments and sonars at depths to 20,000 feet.

Tethered acoustic doppler current profiler platforms for measuring streamflow

USGS Publications Warehouse

Rehmel, Michael S.; Stewart, James A.; Morlock, Scott E.

2003-01-01

A tethered-platform design with a trimaran hull and 900-megahertz radio modems is now commercially available. Continued field use has resulted in U.S. Geological Survey procedures for making tethered-platform discharge measurements, including methods for tethered-boat deployment, moving-bed tests, and measurement of edge distances.

Space station environmental control and life support systems test bed program - an overview

NASA Astrophysics Data System (ADS)

Behrend, Albert F.

As the National Aeronautics and Space Administration (NASA) begins to intensify activities for development of the Space Station, decisions must be made concerning the technical state of the art that will be baselined for the initial Space Station system. These decisions are important because significant potential exists for enhancing system performance and for reducing life-cycle costs. However, intelligent decisions cannot be made without an adequate assessment of new and ready technologies, i.e., technologies which are sufficiently mature to allow predevelopment demonstrations to prove their application feasibility and to quantify the risk associated with their development. Therefore, the NASA has implemented a technology development program which includes the establishment of generic test bed capabilities in which these new technologies and approaches can be tested at the prototype level. One major Space Station subsystem discipline in which this program has been implemented is the environmental control and life support system (ECLSS). Previous manned space programs such as Gemini, Apollo, and Space Shuttle have relied heavily on consumables to provide environmental control and life support services. However, with the advent of a long-duration Space Station, consumables must be reduced within technological limits to minimize Space Station resupply penalties and operational costs. The use of advanced environmental control and life support approaches involving regenerative processes offers the best solution for significant consumables reduction while also providing system evolutionary growth capability. Consequently, the demonstration of these "new technologies" as viable options for inclusion in the baseline that will be available to support a Space Station initial operational capability in the early 1990's becomes of paramount importance. The mechanism by which the maturity of these new regenerative life support technologies will be demonstrated is the Space Station ECLSS Test Bed Program. The Space Station ECLSS Test Bed Program, which is managed by the NASA, is designed to parallel and to provide continuing support to the Space Station Program. The prime objective of this multiphase test bed program is to provide viable, mature, and enhancing technical options in time for Space Station implementation. To accomplish this objective, NASA is actively continuing the development and testing of critical components and engineering preprototype subsystems for urine processing, washwater recovery, water quality monitoring, carbon dioxide removal and reduction, and oxygen generation. As part of the ECLSS Test Bed Program, these regenerative subsystems and critical components are tested in a development laboratory to characterize subsystem performance and to identify areas in which further technical development is required. Proven concepts are then selected for development into prototype subsystems in which flight issues such as packaging and maintenance are addressed. These subsystems then are to be assembled as an integrated system and installed in an integrated systems test bed facility for extensive unmanned and manned testing.

Gasification Product Improvement Facility (GPIF). Final report

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

NONE

1995-09-01

The gasifier selected for development under this contract is an innovative and patented hybrid technology which combines the best features of both fixed-bed and fluidized-bed types. PyGas{trademark}, meaning Pyrolysis Gasification, is well suited for integration into advanced power cycles such as IGCC. It is also well matched to hot gas clean-up technologies currently in development. Unlike other gasification technologies, PyGas can be designed into both large and small scale systems. It is expected that partial repowering with PyGas could be done at a cost of electricity of only 2.78 cents/kWh, more economical than natural gas repowering. It is extremely unfortunatemore » that Government funding for such a noble cause is becoming reduced to the point where current contracts must be canceled. The Gasification Product Improvement Facility (GPIF) project was initiated to provide a test facility to support early commercialization of advanced fixed-bed coal gasification technology at a cost approaching $1,000 per kilowatt for electric power generation applications. The project was to include an innovative, advanced, air-blown, pressurized, fixed-bed, dry-bottom gasifier and a follow-on hot metal oxide gas desulfurization sub-system. To help defray the cost of testing materials, the facility was to be located at a nearby utility coal fired generating site. The patented PyGas{trademark} technology was selected via a competitive bidding process as the candidate which best fit overall DOE objectives. The paper describes the accomplishments to date.« less

Application of Multivariable Model Predictive Advanced Control for a 2×310T/H CFB Boiler Unit

NASA Astrophysics Data System (ADS)

Weijie, Zhao; Zongllao, Dai; Rong, Gou; Wengan, Gong

When a CFB boiler is in automatic control, there are strong interactions between various process variables and inverse response characteristics of bed temperature control target. Conventional Pill control strategy cannot deliver satisfactory control demand. Kalman wave filter technology is used to establish a non-linear combustion model, based on the CFB combustion characteristics of bed fuel inventory, heating values, bed lime inventory and consumption. CFB advanced combustion control utilizes multivariable model predictive control technology to optimize primary and secondary air flow, bed temperature, air flow, fuel flow and heat flux. In addition to providing advanced combustion control to 2×310t/h CFB+1×100MW extraction condensing turbine generator unit, the control also provides load allocation optimization and advanced control for main steam pressure, combustion and temperature. After the successful implementation, under 10% load change, main steam pressure varied less than ±0.07MPa, temperature less than ±1°C, bed temperature less than ±4°C, and air flow (O2) less than ±0.4%.

First results of the Test-Bed Telescopes (TBT) project: Cebreros telescope commissioning

NASA Astrophysics Data System (ADS)

Ocaña, Francisco; Ibarra, Aitor; Racero, Elena; Montero, Ángel; Doubek, Jirí; Ruiz, Vicente

2016-07-01

The TBT project is being developed under ESA's General Studies and Technology Programme (GSTP), and shall implement a test-bed for the validation of an autonomous optical observing system in a realistic scenario within the Space Situational Awareness (SSA) programme of the European Space Agency (ESA). The goal of the project is to provide two fully robotic telescopes, which will serve as prototypes for development of a future network. The system consists of two telescopes, one in Spain and the second one in the Southern Hemisphere. The telescope is a fast astrograph with a large Field of View (FoV) of 2.5 x 2.5 square-degrees and a plate scale of 2.2 arcsec/pixel. The tube is mounted on a fast direct-drive mount moving with speed up to 20 degrees per second. The focal plane hosts a 2-port 4K x 4K back-illuminated CCD with readout speeds up to 1MHz per port. All these characteristics ensure good survey performance for transients and fast moving objects. Detection software and hardware are optimised for the detection of NEOs and objects in high Earth orbits (objects moving from 0.1-40 arcsec/second). Nominal exposures are in the range from 2 to 30 seconds, depending on the observational strategy. Part of the validation scenario involves the scheduling concept integrated in the robotic operations for both sensors. Every night it takes all the input needed and prepares a schedule following predefined rules allocating tasks for the telescopes. Telescopes are managed by RTS2 control software, that performs the real-time scheduling of the observation and manages all the devices at the observatory.1 At the end of the night the observing systems report astrometric positions and photometry of the objects detected. The first telescope was installed in Cebreros Satellite Tracking Station in mid-2015. It is currently in the commissioning phase and we present here the first results of the telescope. We evaluate the site characteristics and the performance of the TBT Cebreros telescope in the different modes and strategies. Average residuals for asteroids are under 0.5 arcsecond, while they are around 1 arcsecond for upper-MEO* and GEO† satellites. The survey depth is dimmer than magnitude 18.5 for 30-second exposures with the usual seeing around 4 arcseconds.

40 CFR 60.41b - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... produces both electric (or mechanical) and useful thermal energy from the same primary energy source. Coke.... Conventional technology means wet flue gas desulfurization (FGD) technology, dry FGD technology, atmospheric fluidized bed combustion technology, and oil hydrodesulfurization technology. Distillate oil means fuel oils...

Experiment Investigation of the Influencing Factors on Bed Agglomeration During Fluidized-Bed Gasification of Biomass Fuels

NASA Astrophysics Data System (ADS)

Chen, Y. Q.; Chen, H. P.; Yang, H. P.; Wang, X. H.; Zhang, S. H.

With the depleting of fossil fuel and environmental polluting increasing, the utilization of biomass resources caught increasing concern. Biomass gasification in fluidized bed, as one promising technology, developed quickly. However, serious agglomeration was displayed as biomass ash reacted with bed material (silica sand) at higher temperature. It hindered the wide utilization of CFB gasifier. The objective ofthis work is to investigate the agglomeration behavior between biomass ash and silica sand, and catch the inherent mechanism. Firstly, the influence of ash compounds on the agglomeration behavior was analyzed with biomass ash and synthesis ash compounds addition in fixed bed as ash sample mixed with bed material evenly before every trial. The reaction temperature was set 850°C that is the operated temperature for many fluidized bed gasificated biomass fuels. Then the influence of reaction time was analyzed. The characteristics of the agglomerated silica sand particles were analyzed by the XRD. Finally, it was simulated with HSC computer mode based on thermodynamic equilibrium. It was observed that when the ratio of the biomass ash to the silica sand was above 0.2, the agglomeration was observed. With the increase of the reaction time, more silica sand particles agglomerated with the biomass ash. There are two kinds of silicate eutecticum investigated by the XRD. It is of great significance for the running ofCFB biomass gasifier and the development ofbiomass utilization technology.

Sediment supply controls equilibrium channel geometry in gravel rivers

PubMed Central

Finnegan, Noah J.; Willenbring, Jane K.

2017-01-01

In many gravel-bedded rivers, floods that fill the channel banks create just enough shear stress to move the median-sized gravel particles on the bed surface (D50). Because this observation is common and is supported by theory, the coincidence of bankfull flow and the incipient motion of D50 has become a commonly used assumption. However, not all natural gravel channels actually conform to this simple relationship; some channels maintain bankfull stresses far in excess of the critical stress required to initiate sediment transport. We use a database of >300 gravel-bedded rivers and >600 10Be-derived erosion rates from across North America to explore the hypothesis that sediment supply drives the magnitude of bankfull shear stress relative to the critical stress required to mobilize the median bed surface grain size (τbf*/τc*). We find that τbf*/τc* is significantly higher in West Coast river reaches (2.35, n = 96) than in river reaches elsewhere on the continent (1.03, n = 245). This pattern parallels patterns in erosion rates (and hence sediment supplies). Supporting our hypothesis, we find a significant correlation between upstream erosion rate and local τbf*/τc* at sites where this comparison is possible. Our analysis reveals a decrease in bed surface armoring with increasing τbf*/τc*, suggesting channels accommodate changes in sediment supply through adjustments in bed surface grain size, as also shown through numerical modeling. Our findings demonstrate that sediment supply is encoded in the bankfull hydraulic geometry of gravel bedded channels through its control on bed surface grain size. PMID:28289212

Flume Experiments on the Influence of Salmon Spawning Density on Grain Stability and Bedload Transport in Gravel-bed Streams

NASA Astrophysics Data System (ADS)

Buxton, T. H.

2015-12-01

Salmon spawning in streams involves the female salmon digging a pit in the bed where she deposits eggs for fertilization before covering them with gravel excavated from the next pit upstream. Sequences of pit excavation and filling winnow fines, loosen sediment, and move bed material into a tailspill mound resembling the shape of a dune. Research suggests salmonid nests (redds) destabilize streambeds by reducing friction between loosened grains and converging flow that elevates shear stress on redd topography. However, bed stability may be enhanced by form drag from redds in clusters that lower shear stress on the granular bed, but this effect will vary with the proportion of the bed surface that is occupied by redds (P). I used simulated redds and water-worked ("unspawned") beds in a laboratory flume to evaluate these competing influences on grain stability and bedload transport rates with P=0.12, 0.34, and 0.41. Results indicate that competence (largest-grain) and reference transport rate estimates of critical conditions for particle entrainment inversely relate to P. Bedload transport increased as exponential functions of P and excess boundary shear stress. Therefore, redd form drag did not overcome the destabilizing effects of spawning. Instead, grain mobility and bedload transport increased with P because larger areas of the bed were composed of relatively loose, unstable grains and redd topography that experienced elevated shear stress. Consequently, the presence of redds in fish-bearing streams likely reduces the effects of sedimentation from landscape disturbance on stream habitats that salmon use for reproduction.

Intrahospital transfers and adverse patient outcomes: An analysis of administrative health data.

PubMed

Blay, Nicole; Roche, Michael; Duffield, Christine; Xu, Xiaoyue

2017-12-01

To determine whether there was an association between intra-hospital transfers and adverse outcomes. Transfers between clinical units and between beds on the same unit are routine aspects of an episode of care in acute hospitals. The rate of these transfers per episode has increased in response to high occupancy levels, a decline in bed numbers, and increased demand for hospital services. The impact of the number of transfers between both wards and beds on patient outcomes is not widely explored. Retrospective cross sectional design using hospital administrative data. Data were extracted from existing hospital administrative datasets for one large metropolitan hospital for the financial year 2008-09 in Australia (n = 14,133). Descriptive analyses and logistic regression models were developed for each of 3 selected patient outcomes. Nearly one-tenth of patients (9.2%) experienced a fall with injury, 3.8% of surgical patients a wound infection and 0.1% a complication from medication errors. For each bed or ward transfer, the odds of falls and wound infections increased. Medication errors were not associated with either bed or ward moves. Hospitals should minimise the number of bed and ward transfers per episode of care in order to reduce the likelihood of adverse patient outcomes. Current bed management policies and practices should be evaluated and further refined to address this need. Additional strategies include improving coordination and communication during and after transfer. Nurses must consider the potential cost of intrahospital transfers on patients, length of stay and bed availability. © 2017 John Wiley & Sons Ltd.

Space Transportation Technology Workshop: Propulsion Research and Technology

NASA Technical Reports Server (NTRS)

2000-01-01

This viewgraph presentation gives an overview of the Space Transportation Technology Workshop topics, including Propulsion Research and Technology (PR&T) project level organization, FY 2001 - 2006 project roadmap, points of contact, foundation technologies, auxiliary propulsion technology, PR&T Low Cost Turbo Rocket, and PR&T advanced reusable technologies RBCC test bed.

Advanced Turbine Technology Applications Project (ATTAP)

NASA Technical Reports Server (NTRS)

1991-01-01

ATTAP activities were highlighted by test bed engine design and development activities; ceramic component design; materials and engine component characterization; ceramic component process development and fabrication; component rig testing; and test bed engine fabrication and testing. Specifically, ATTAP aims to develop and demonstrate the technology of structural ceramics that have the potential for competitive automotive engine life cycle cost and for operating for 3500 hours in a turbine engine environment at temperatures up to 1371 C (2500 F).

Test Bed For Telerobots

NASA Technical Reports Server (NTRS)

Matijevic, Jacob R.; Zimmerman, Wayne F.; Dolinsky, Shlomo

1990-01-01

Assembly of electromechanical and electronic equipment (including computers) constitutes test bed for development of advanced robotic systems for remote manipulation. Combines features not found in commercial systems. Its architecture allows easy growth in complexity and level of automation. System national resource for validation of new telerobotic technology. Intended primarily for robots used in outer space, test bed adapted to development of advanced terrestrial telerobotic systems for handling radioactive materials, dangerous chemicals, and explosives.

National Gas Survey report to the Federal Energy Regulatory Commission by the Supply-Technical Advisory Task Force on nonconventional natural gas resources. [Coal beds

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

None

1978-06-01

An analysis is presented of the future energy situation in the U.S. with emphasis on the natural gas industry. The analysis results are presented in chapters on historical research efforts, industry criteria for commercialization of coal bed gas, technology for recovering methane from coal beds, identification of problems, legal concerns, and environmental considerations. (JRD)

The underlying reasons for very high levels of bed net use, and higher malaria infection prevalence among bed net users than non-users in the Tanzanian city of Dar es Salaam: a qualitative study.

PubMed

Msellemu, Daniel; Shemdoe, Aloysia; Makungu, Christina; Mlacha, Yeromini; Kannady, Khadija; Dongus, Stefan; Killeen, Gerry F; Dillip, Angel

2017-10-23

Bed nets reduce malaria-related illness and deaths, by forming a protective barrier around people sleeping under them. When impregnated with long-lasting insecticide formulations they also repel or kill mosquitoes attempting to feed upon sleeping humans, and can even suppress entire populations of malaria vectors that feed predominantly upon humans. Nevertheless, an epidemiological study in 2012 demonstrated higher malaria prevalence among bed net users than non-users in urban Dar es Salaam, Tanzania. Focus group discussions were conducted with women from four selected wards of Dar es Salaam city, focusing on four major themes relating to bed net use behaviours: (1) reasons for bed net use, (2) reasons for not using bed nets, (3) stimuli or reminders for people to use a bed net (4) perceived reasons for catching malaria while using a bed net. An analytical method by framework grouping of relevant themes was used address key issues of relevance to the study objectives. Codes were reviewed and grouped into categories and themes. All groups said the main reason for bed net use was protection against malaria. Houses with well-screened windows, with doors that shut properly, and that use insecticidal sprays against mosquitoes, were said not to use bed nets, while frequent attacks from malaria was the main stimulus for people to use bed nets. Various reasons were mentioned as potential reasons that compromise bed net efficacy, the most common of which were: (1) bed net sharing by two or more people, especially if one occupant tends to come to bed late at night, and does not tuck in the net 71%; (2) one person shares the bed but does not use the net, moving it away from the side on which s/he sleeps 68%; (3) ineffective usage habits, called ulalavi, in which a sprawling sleeper either touches the net while sleeping up against it or leaves a limb hanging outside of it 68%. Less common reasons mentioned included: (1) Small bed nets which become un-tucked at night (31%); (2) Bed nets with holes large enough to allow mosquitoes to pass (28%); and (3) Going to bed late after already being bitten outdoors (24%). Behaviours associated with bed net use like; bed sharing, bed net non compliant-bedfellow, sleeping pattern like ulalavi and some physical bed net attributes compromise its effectiveness and supposedly increase of malaria infection to bed net users. While some well-screened houses looked to instigate low malaria prevalence to non-bed net users.

Clinical physiology of bed rest

NASA Technical Reports Server (NTRS)

Greenleaf, John E.

1993-01-01

Maintenance of optimal health in humans requires the proper balance between exercise, rest, and sleep as well as time in the upright position. About one-third of a lifetime is spent sleeping; and it is no coincidence that sleeping is performed in the horizontal position, the position in which gravitational influence on the body is minimal. Although enforced bed rest is necessary for the treatment of some ailments, in some cases it has probably been used unwisely. In addition to the lower hydrostatic pressure with the normally dependent regions of the cardiovascular system, body fuid compartments during bed rest in the horizontal body position, and virtual elimination of compression on the long bones of the skeletal system during bed rest (hypogravia), there is often reduction in energy metabolism due to the relative confinement (hypodynamia) and alteration of ambulatory circadian variations in metabolism, body temperature, and many hormonal systems. If patients are also moved to unfamiliar surroundings, they probably experience some feelings of anxiety and some sociopsychological problems. Adaptive physiological responses during bed rest are normal for that environment. They are attempts by the body to reduce unnecessary energy expenditure, to optimize its function, and to enhance its survival potential. Many of the deconditioning responses begin within the first day or two of bed rest; these early responses have prompted physicians to insist upon early resumption of the upright posture and ambulation of bedridden patients.

1300°F 800 MWe USC CFB Boiler Design Study

NASA Astrophysics Data System (ADS)

Robertson, Archie; Goidich, Steve; Fan, Zhen

Concern about air emissions and the effect on global warming is one of the key factors for developing and implementing new advanced energy production solutions today. One state-of-the-art solution is circulating fluidized bed (CFB) combustion technology combined with a high efficiency once-through steam cycle. Due to this extremely high efficiency, the proven CFB technology offers a good solution for CO2 reduction. Its excellent fuel flexibility further reduces CO2 emissions by co-firing coal with biomass. Development work is under way to offer CFB technology up to 800MWe capacities with ultra-supercritical (USC) steam parameters. In 2009 a 460MWe once-through supercritical (OTSC) CFB boiler designed and constructed by Foster Wheeler will start up. However, scaling up the technology further to 600-800MWe with net efficiency of 45-50% is needed to meet the future requirements of utility operators. To support the move to these larger sizes, an 800MWe CFB boiler conceptual design study was conducted and is reported on herein. The use of USC conditions (˜11 00°F steam) was studied and then the changes, that would enable the unit to generate 1300°F steam, were identified. The study has shown that by using INTREX™ heat exchangers in a unique internal-external solids circulation arrangement, Foster Wheeler's CFB boiler configuration can easily accommodate 1300°F steam and will not require a major increase in heat transfer surface areas.

Assessing the use of an infrared spectrum hyperpixel array imager to measure temperature during additive and subtractive manufacturing

NASA Astrophysics Data System (ADS)

Whitenton, Eric; Heigel, Jarred; Lane, Brandon; Moylan, Shawn

2016-05-01

Accurate non-contact temperature measurement is important to optimize manufacturing processes. This applies to both additive (3D printing) and subtractive (material removal by machining) manufacturing. Performing accurate single wavelength thermography suffers numerous challenges. A potential alternative is hyperpixel array hyperspectral imaging. Focusing on metals, this paper discusses issues involved such as unknown or changing emissivity, inaccurate greybody assumptions, motion blur, and size of source effects. The algorithm which converts measured thermal spectra to emissivity and temperature uses a customized multistep non-linear equation solver to determine the best-fit emission curve. Emissivity dependence on wavelength may be assumed uniform or have a relationship typical for metals. The custom software displays residuals for intensity, temperature, and emissivity to gauge the correctness of the greybody assumption. Initial results are shown from a laser powder-bed fusion additive process, as well as a machining process. In addition, the effects of motion blur are analyzed, which occurs in both additive and subtractive manufacturing processes. In a laser powder-bed fusion additive process, the scanning laser causes the melt pool to move rapidly, causing a motion blur-like effect. In machining, measuring temperature of the rapidly moving chip is a desirable goal to develop and validate simulations of the cutting process. A moving slit target is imaged to characterize how the measured temperature values are affected by motion of a measured target.

Researchers evaluate low-energy recirculating system for inland production of marine finfish juveniles

USDA-ARS?s Scientific Manuscript database

The low-energy recirculating aquaculture system consists of nine separate modules which utilize the double drain fish culture tank paired to a moving bed biofilter. The nine fiberglass tanks are five feet in diameter and normal water depth is about three feet for a total tank volume of approximately...

Lateral and vertical channel movement and potential for bed-material movement on the Madison River downstream from Earthquake Lake, Montana

USGS Publications Warehouse

Chase, Katherine J.; McCarthy, Peter M.

2012-01-01

The 1959 Hebgen Lake earthquake caused a massive landslide (Madison Slide) that dammed the Madison River and formed Earthquake Lake. The U.S. Army Corps of Engineers excavated a spillway through the Madison Slide to permit outflow from Earthquake Lake. In June 1970, high streamflows on the Madison River severely eroded the spillway channel and damaged the roadway embankment along U.S. Highway 287 downstream from the Madison Slide. Investigations undertaken following the 1970 flood events concluded that substantial erosion through and downstream from the spillway could be expected for streamflows greater than 3,500 cubic feet per second (ft3/s). Accordingly, the owners of Hebgen Dam, upstream from Earthquake Lake, have tried to manage releases from Hebgen Lake to prevent streamflows from exceeding 3,500 ft3/s measured at the U.S. Geological Survey (USGS) gaging station 0638800 Madison River at Kirby Ranch, near Cameron, Montana. Management of flow releases from Hebgen Lake to avoid exceeding the threshold streamflow at USGS gaging station 06038800 is difficult, and has been questioned for two reasons. First, no road damage was reported downstream from the Earthquake Lake outlet in 1993, 1996, and 1997 when streamflows exceeded the 3,500-ft3/s threshold. Second, the 3,500-ft3/s threshold generally precludes releases of higher flows that could be beneficial to the blue-ribbon trout fishery downstream in the Madison River. In response to concerns about minimizing streamflow downstream from Earthquake Lake and the possible armoring of the spillway, the USGS, in cooperation with the Madison River Fisheries Technical Advisory Committee (MADTAC; Bureau of Land Management; Montana Department of Environmental Quality; Montana Fish, Wildlife and Parks; PPL-Montana; U.S. Department of Agriculture Forest Service - Gallatin National Forest; and U.S. Fish and Wildlife Service), conducted a study to determine movement of the Madison River channel downstream from Earthquake Lake and to investigate the potential for bed material movement along the same reach. The purpose of this report is to present information about the lateral and vertical movement of the Madison River from 1970 to 2006 for a 1-mile reach downstream from Earthquake Lake and for Raynolds Pass Bridge, and to provide an analysis of the potential for bed-material movement so that MADTAC can evaluate the applicability of the previously determined threshold streamflow for initiation of damaging erosion. As part of this study channel cross sections originally surveyed by the USGS in 1971 were resurveyed in 2006. Incremental channel-movement distances were determined by comparing the stream centerlines from 14 aerial photographs taken between 1970 and 2006. Depths of channel incision and aggregation were determined by comparing the 2006 and 1971 cross-section and water-surface data. Particle sizes of bed and bank materials were measured in 2006 and 2008 using the pebble-count method and sieve analyses. A one-dimensional hydraulic-flow model (HEC-RAS) was used to calculate mean boundary-shear stresses for various streamflows; these calculated boundary-shear stresses were compared to calculated critical-shear stresses for the bed materials to determine the potential for bed-material movement. A comparison of lateral channel movement distances with annual peak streamflows shows that streamflows higher than the 3,500-ft3/s threshold were followed by lateral channel movement except from 1991 to 1992 and possibly from 1996 to 1997. However, it was not possible to discern whether the channel moved gradually or suddenly, or in response to one peak flow, to several peak flows, or to sustained flows. The channel moved between 2002 and 2005 even when streamflows were less than the threshold streamflow of 3,500 ft3/s. Comparisons of cross sections and aerial photographs show that the channel has moved laterally and incised and aggraded to varying degrees. The channel has developed meander bends and has incised as much as 5–12 feet (ft) through the upstream part of the Madison Slide (cross sections 1400–800). Near cross section 800, the stream has eroded into the steep right bank between the stream and the road where fill was mechanically placed after 1970. Channel movement also was noted downstream from the Madison Slide. Near Raynolds Pass Bridge, about 3 miles (mi) downstream from Earthquake Lake, elevations across the channel have changed by -1.4 ft to +1.9 ft, but these changes were local in nature and could represent a few rocks or depressions in the bed. Overall, it does not appear that the materials eroded from the Madison Slide are causing aggradation in the subreach near the Raynolds Pass Bridge. Comparisons of critical shear stresses to mean boundary-shear stresses indicate that the D50 particle sizes (median size) along the right side of the bed between cross sections 400 and 500 and along the right side of the bed between cross sections 1300 and 1400 could move at the threshold streamflow. In contrast, most of the D84 particle sizes at those two locations probably will not move at the threshold streamflow. This lack of movement for the larger particles at the threshold streamflow could lead to further armoring of the bed as the D50 and smaller-sized particles are removed from the bed and transported downstream. The Shields parameter values from 0.04 to 0.08 that were used to calculate critical shear stresses could be conservative for a high-gradient stream such as the Madison. A higher, less conservative, Shields parameter would result in higher critical shear stresses, meaning that higher streamflows would be required to move material than those reported herein. In addition, because materials in the channel thalweg are exposed to higher boundary-shear stresses than the materials along the sides of the channel, larger, more erosion-resistant materials likely exist in the deeper parts of the channel where high-flow depths and velocities prevented sediment sampling. Movement of these materials might require higher critical shear stresses than estimated in this report. Characterization of sediment sizes in the center of the stream and observation of bed-material movement for a range of streamflows could provide information to help refine the Shields parameter and critical-shear stress estimates for bed materials in the Madison River downstream from Earthquake Lake. Furthermore, resurveying cross sections and water-surface elevations more frequently (either annually or after high streamflows) could better define the relation between streamflow and lateral and vertical channel movement.

Thermal Analysis of Fluidized Bed and Fixed Bed Latent Heat Thermal Storage System

NASA Astrophysics Data System (ADS)

Beemkumar, N.; Karthikeyan, A.; Shiva Keshava Reddy, Kota; Rajesh, Kona; Anderson, A.

2017-05-01

Thermal energy storage technology is essential because its stores available energy at low cost. Objective of the work is to store the thermal energy in a most efficient method. This work is deal with thermal analysis of fluidized bed and fixed bed latent heat thermal storage (LHTS) system with different encapsulation materials (aluminium, brass and copper). D-Mannitol has been used as phase change material (PCM). Encapsulation material which is in orbicular shape with 4 inch diameter and 2 mm thickness orbicular shaped product is used. Therminol-66 is used as a heat transfer fluid (HTF). Arrangement of encapsulation material is done in two ways namely fluidized bed and fixed bed thermal storage system. Comparison was made between the performance of fixed bed and fluidized bed with different encapsulation material. It is observed that from the economical point of view aluminium in fluidized bed LHTS System has highest efficiency than copper and brass. The thermal energy storage system can be analyzed with fixed bed by varying mass flow rate of oil paves a way to find effective heat energy transfer.

Sediment motion and velocity in a glacier-fed stream

NASA Astrophysics Data System (ADS)

Mao, L.; Dell'Agnese, A.; Comiti, F.

2017-08-01

Current understanding of coarse sediment transport (e.g. threshold for motion, travel length and virtual velocity) in mountain rivers is still quite limited, and even less is known about glacial streams. However, the hydrological characteristics of these systems (strong daily discharge fluctuations, high water turbidity) pose challenges to the use of tracers to monitor bed sediment dynamics, as tagged clasts are usually located after bedload events when flow stage has receded, e.g. by means of portable antennas in the case of Passive Integrated Transponders (PIT). The use of stationary antennas, still scarcely in use worldwide, to detect PIT-tagged particles has potential advantages in glacier-fed streams. If water discharge is monitored continuously, a stationary antenna provides real time data on the actual discharge at the moment of tracer particles passage. This study focuses on incipient motion and virtual velocity of bed particles measured by a stationary antennas system in a steep mountain channel (Saldur River, drainage area 18.6 km2, Italian Alps) where significant daily discharge fluctuations and bedload transport occur as a result of a nivo-glacial regime. Four stationary antennas were installed 50-m apart in the study reach. A total of 629 PIT-tagged clasts were inserted in the studied reach between 2011 and 2014, ranging in size from 35 mm to 580 mm, with an overall recovery rate of around 44%. Critical discharge for sediment entrainment was obtained by detecting the movement of tracers placed immediately upstream of antennas. Virtual velocity was derived by knowing distances between the antennas and travel time of tracers. Results on initiation of motion show that the relationship between the size of transported tracers and the discharge measured at the time clasts were passing the stationary antenna is very weak. The influence of antecedent flows on incipient motion was thus investigated by dividing the highest discharge recorded between each PIT deployment and the subsequent entrainment by the actual critical discharge at the time of movement (ratio Qmax/Qc). Results show that approximately 50% of tracers moved at Qmax/Qc ≤ 1.2, and that 73% of tracers moved at Qmax/Qc < 1.5. Therefore, about 30% of tracers had to previously experience a discharge substantially greater than the one that actually mobilized them. Also, coarser particles moved at higher Qmax/Qc ratios, suggesting that higher antecedent flows may be needed to destabilize bed clustering. Results on the virtual velocity of the PIT-tagged clasts employed in the field show that the virtual velocity turned out to be highly variable (ranging from 101 to 10- 5 m min- 1) and weakly related to either particle size or flow discharge. However, virtual velocity was well correlated with the highest flow discharge experienced by each tracer normalized by a percentile of the flow duration curve. This evidence further stresses the importance of flow history on sediment entrainment and transport. Finally, the pros and cons of the deployed monitoring technology are discussed.

Treatment of petroleum refinery wastewater using a sequential anaerobic-aerobic moving-bed biofilm reactor system based on suspended ceramsite.

PubMed

Lu, Mang; Gu, Li-Peng; Xu, Wen-Hao

2013-01-01

In this study, a novel suspended ceramsite was prepared, which has high strength, optimum density (close to water), and high porosity. The ceramsite was used to feed a moving-bed biofilm reactor (MBBR) system with an anaerobic-aerobic (A/O) arrangement to treat petroleum refinery wastewater for simultaneous removal of chemical oxygen demand (COD) and ammonium. The hydraulic retention time (HRT) of the anaerobic-aerobic MBBR system was varied from 72 to 18 h. The anaerobic-aerobic system had a strong tolerance to shock loading. Compared with the professional emission standard of China, the effluent concentrations of COD and NH3-N in the system could satisfy grade I at HRTs of 72 and 36 h, and grade II at HRT of 18 h. The average sludge yield of the anaerobic reactor was estimated to be 0.0575 g suspended solid/g CODremoved. This work demonstrated that the anaerobic-aerobic MBBR system using the suspended ceramsite as bio-carrier could be applied to achieving high wastewater treatment efficiency.

Phenol removal performance and microbial community shift during pH shock in a moving bed biofilm reactor (MBBR).

PubMed

Zhou, Hao; Wang, Guochen; Wu, Minghuo; Xu, Weiping; Zhang, Xuwang; Liu, Lifen

2018-06-05

A moving bed biofilm reactor (MBBR) effectively removes pollutants and even runs under extreme conditions. However, the pH shock resistance of a biofilm in MBBRs has been rarely reported. In this study, simulated phenol wastewater with acidic shock (pH 7.5-3.0) was used. In the pH shock phase, the phenol and COD removal efficiencies initially decreased and gradually increased to more than 90%. Microscopic studies showed that the superficial biofilm was mainly composed of fungi (yeasts) in the acidic pH shock phase. The microbial community composition in the acidic pH shock phase was significantly different from those in other phases. Firmicutes and Ascomycota were the dominant bacterial and fungal phyla in this stage, respectively. 16S rRNA gene-based functional annotation indicated that functional profiles related to aromatic compound degradation existed in all of the stages. Therefore, MBBRs show potential for the treatment of phenolic wastewater exposed to pH shock. Copyright © 2018 Elsevier B.V. All rights reserved.

Evaluation of micropollutant removal and fouling reduction in a hybrid moving bed biofilm reactor-membrane bioreactor system.

PubMed

Luo, Yunlong; Jiang, Qi; Ngo, Huu H; Nghiem, Long D; Hai, Faisal I; Price, William E; Wang, Jie; Guo, Wenshan

2015-09-01

A hybrid moving bed biofilm reactor-membrane bioreactor (MBBR-MBR) system and a conventional membrane bioreactor (CMBR) were compared in terms of micropollutant removal efficiency and membrane fouling propensity. The results show that the hybrid MBBR-MBR system could effectively remove most of the selected micropollutants. By contrast, the CMBR system showed lower removals of ketoprofen, carbamazepine, primidone, bisphenol A and estriol by 16.2%, 30.1%, 31.9%, 34.5%, and 39.9%, respectively. Mass balance calculations suggest that biological degradation was the primary removal mechanism in the MBBR-MBR system. During operation, the MBBR-MBR system exhibited significantly slower fouling development as compared to the CMBR system, which could be ascribed to the wide disparity in the soluble microbial products (SMP) levels between MBBR-MBR (4.02-6.32 mg/L) and CMBR (21.78 and 33.04 mg/L). It is evident that adding an MBBR process prior to MBR treatment can not only enhance micropollutant elimination but also mitigate membrane fouling. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of kenaf fibers as moving bed biofilm carriers in algal membrane photobioreactor.

PubMed

Derakhshan, Zahra; Mahvi, Amir Hossein; Ehrampoush, Mohammad Hassan; Ghaneian, Mohammad Taghi; Yousefinejad, Saeed; Faramarzian, Mohammad; Mazloomi, Seyed Mohammad; Dehghani, Mansooreh; Fallahzadeh, Hossein

2018-05-15

In this lab-scale study, the feasibility of using kenaf fibers as moving bed biofilm carriers in hybrid microalgal membrane photobioreactors (HMPBR) in organic matter and atrazine elimination from real secondary effluent was evaluated. For evaluating the kinetics of biofilm substrate consumption, an experimental model was proposed. Inoculation of wastewater samples with free carriers resulted in the greater removal of target pollutants. Removal efficiency of atrazine and chemical oxygen demand (COD) increased to 27% and 16%, with respect to the control, respectively. The total biomass accumulation in HMPBR exceeded 5g/L, and the microalgae tended to aggregate and attached to biofilm carriers. The removal efficiency of HMPBR improved significantly via inoculation of kenaf fiber carriers with bioremediation microalgal strains (p < 0.01). A lower stabilization ratio (VSS/TSS) was also recorded. The biomass in HMPBR included more lipids and carbohydrates. The results revealed that kenaf fibers could improve and upgrade the biological activity of different wastewater treatment applications, considering the great potential of biofilm carriers and their effluent quality. Copyright © 2018 Elsevier Inc. All rights reserved.

Improvement of poly-γ-glutamic acid biosynthesis in a moving bed biofilm reactor by Bacillus subtilis NX-2.

PubMed

Jiang, Yongxiang; Tang, Bao; Xu, Zongqi; Liu, Kun; Xu, Zheng; Feng, Xiaohai; Xu, Hong

2016-10-01

The production of poly-γ-glutamic acid (γ-PGA) by Bacillus subtilis NX-2 using a moving bed biofilm reactor (MBBR) system was tested for the first time in this study. Polypropylene TL-2 was chosen as a suitable carrier, and γ-PGA concentration of 42.7±0.86g/L and productivity of 0.59±0.06g/(Lh) were obtained in batch fermentation. After application of the strategy of dissolved oxygen (DO)-stat feeding, higher γ-PGA concentration and productivity were achieved than with glucose feedback feeding. Finally, the repeated fed-batch cultures implemented in the MBBR system showed high stability, and the maximal γ-PGA concentration and productivity of 74.2g/L and 1.24g/(Lh) were achieved, respectively. In addition, the promotion of oxygen transfer by an MBBR carrier was well explained by a computational fluid dynamics (CFD) simulation. These results suggest that an MBBR system could be applied to large-scale γ-PGA production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Isolation and metagenomic characterization of bacteria associated with calcium carbonate and struvite precipitation in a pure moving bed biofilm reactor-membrane bioreactor.

PubMed

Gonzalez-Martinez, A; Leyva-Díaz, J C; Rodriguez-Sanchez, A; Muñoz-Palazon, B; Rivadeneyra, A; Poyatos, J M; Rivadeneyra, M A; Martinez-Toledo, M V

2015-01-01

A bench-scale pure moving bed bioreactor-membrane bioreactor (MBBR-MBR) used for the treatment of urban wastewater was analyzed for the identification of bacterial strains with the potential capacity for calcium carbonate and struvite biomineral formation. Isolation of mineral-forming strains on calcium carbonate and struvite media revealed six major colonies with a carbonate or struvite precipitation capacity in the biofouling on the membrane surface and showed that heterotrophic bacteria with the ability to precipitate calcium carbonate and struvite constituted ~7.5% of the total platable bacteria. These belonged to the genera Lysinibacillus, Trichococcus, Comamomas and Bacillus. Pyrosequencing analysis of the microbial communities in the suspended cells and membrane biofouling showed a high degree of similarity in all the samples collected with respect to bacterial assemblage. The study of operational taxonomic units (OTUs) identified through pyrosequencing suggested that ~21% of the total bacterial community identified in the biofouling could potentially form calcium carbonate or struvite crystals in the pure MBBR-MBR system used for the treatment of urban wastewater.

Bed load tracer mobility in a mixed bedrock/alluvial channel

NASA Astrophysics Data System (ADS)

Ferguson, R. I.; Sharma, B. P.; Hodge, R. A.; Hardy, R. J.; Warburton, J.

2017-04-01

The presence of bare or partially covered rock in an otherwise alluvial river implies a downstream change in transport capacity relative to supply. Field investigations of this change and what causes it are lacking. We used two sets of magnet-tagged tracer clasts to investigate bed load transport during the same sequence of floods in fully alluvial, bare rock, and partial-cover reaches of an upland stream. High-flow shear stresses in different reaches were calculated by using stage loggers. Tracers seeded in the upstream alluvial channel moved more slowly than elsewhere until the frontrunners reached bare rock and sped up. Tracers seeded on bare rock moved rapidly off it and accumulated just upstream from, and later in, a partial-cover zone with many boulders. The backwater effect of the boulder-rich zone is significant in reducing tracer mobility. Tracer movement over full or partial sediment cover was size selective but dispersion over bare rock was not. Along-channel changes in tracer mobility are interpreted in terms of measured differences in shear stress and estimated differences in threshold stress.

A study on the use of the BioBall® as a biofilm carrier in a sequencing batch reactor.

PubMed

Masłoń, Adam; Tomaszek, Janusz A

2015-11-01

Described in this study are experiments conducted to evaluate the removal of organics and nutrients from synthetic wastewater by a moving bed sequencing batch biofilm reactor using BioBall® carriers as biofilm media. The work involving a 15L-laboratory scale MBSBBR (moving bed sequencing batch biofilm reactor) model showed that the wastewater treatment system was based on biochemical processes taking place with activated sludge and biofilm microorganisms developing on the surface of the BioBall® carriers. Classical nitrification and denitrification and the typical enhanced biological phosphorus removal process were achieved in the reactor analyzed, which operated with a volumetric organic loading of 0.84-0.978gCODL(-1)d(-1). The average removal efficiencies for COD, total nitrogen and total phosphorus were found to be 97.7±0.5%, 87.8±2.6% and 94.3±1.3%, respectively. Nitrification efficiency reached levels in the range 96.5-99.7%. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization of the moving-bed biofilm sequencing batch reactor (MBSBR) to control aeration time by kinetic computational modeling: Simulated sugar-industry wastewater treatment.

PubMed

Faridnasr, Maryam; Ghanbari, Bastam; Sassani, Ardavan

2016-05-01

A novel approach was applied for optimization of a moving-bed biofilm sequencing batch reactor (MBSBR) to treat sugar-industry wastewater (BOD5=500-2500 and COD=750-3750 mg/L) at 2-4 h of cycle time (CT). Although the experimental data showed that MBSBR reached high BOD5 and COD removal performances, it failed to achieve the standard limits at the mentioned CTs. Thus, optimization of the reactor was rendered by kinetic computational modeling and using statistical error indicator normalized root mean square error (NRMSE). The results of NRMSE revealed that Stover-Kincannon (error=6.40%) and Grau (error=6.15%) models provide better fits to the experimental data and may be used for CT optimization in the reactor. The models predicted required CTs of 4.5, 6.5, 7 and 7.5 h for effluent standardization of 500, 1000, 1500 and 2500 mg/L influent BOD5 concentrations, respectively. Similar pattern of the experimental data also confirmed these findings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Treatment of oil sands process-affected water using moving bed biofilm reactors: With and without ozone pretreatment.

PubMed

Shi, Yijing; Huang, Chunkai; Rocha, Ketley Costa; El-Din, Mohamed Gamal; Liu, Yang

2015-09-01

Two moving bed biofilm reactors (MBBRs) were operated to treat raw (untreated) and 30 mg/L ozone-treated oil sands process-affected water (OSPW). After 210 days, the MBBR process showed 18.3% of acid-extractable fraction (AEF) and 34.8% of naphthenic acids (NAs) removal, while the ozonation combined MBBR process showed higher removal of AEF (41.0%) and NAs (78.8%). Biodegradation of raw and ozone treated OSPW showed similar performance. UPLC/HRMS analysis showed a highest NAs removal efficiency with a carbon number of 14 and a -Z number of 4. Confocal laser scanning microscopy (CLSM) showed thicker biofilms in the raw OSPW MBBR (97 ± 5 μm) than in the ozonated OSPW MBBR (71 ± 12 μm). Quantitative polymerase chain reaction (q-PCR) results showed higher abundance of gene copies of total bacteria and nitrogen removal relevant bacteria in the ozonated OSPW MBBR, but no significant difference was found. MiSeq sequencing showed Proteobacteria, Nitrospirae, and Acidobacteria were dominant. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biodegradation of atrazine from wastewater using moving bed biofilm reactor under nitrate-reducing conditions: A kinetic study.

PubMed

Derakhshan, Zahra; Ehrampoush, Mohammad Hassan; Mahvi, Amir Hossein; Ghaneian, Mohammad Taghi; Mazloomi, Seyed Mohammad; Faramarzian, Mohammad; Dehghani, Mansooreh; Fallahzadeh, Hossein; Yousefinejad, Saeed; Berizi, Enayat; Bahrami, Shima

2018-04-15

In this study employed an anoxic moving bed biofilm reactor (AnMBBR) to evaluate the effects of hydraulic and toxic shocks on performance reactor. The results indicated a relatively good resistance of system against exercised shocks and its ability to return to steady-state conditions. In optimal conditions when there was the maximum rate of atrazine and soluble chemical oxygen demand (COD) removal were 74.82% and 99.29% respectively. Also, atrazine biodegradation rapidly declines in AnMBBR from 74% ± 0.05 in the presence of nitrate to 9.12% only 3 days after the nitrate was eliding from the influent. Coefficients kinetics was studied and the maximum atrazine removal rate was determined by modified Stover & Kincannon model (U max  = 9.87 g ATZ /m 3 d). Results showed that AnMBBR is feasible, easy, affordable, so suitable process for efficiently biodegrading toxic chlorinated organic compounds such as atrazine. Also, its removal mechanism in this system is co-metabolism. Copyright © 2018 Elsevier Ltd. All rights reserved.

Model-based design of an intermittent simulated moving bed process for recovering lactic acid from ternary mixture.

PubMed

Song, Mingkai; Cui, Linlin; Kuang, Han; Zhou, Jingwei; Yang, Pengpeng; Zhuang, Wei; Chen, Yong; Liu, Dong; Zhu, Chenjie; Chen, Xiaochun; Ying, Hanjie; Wu, Jinglan

2018-08-10

An intermittent simulated moving bed (3F-ISMB) operation scheme, the extension of the 3W-ISMB to the non-linear adsorption region, has been introduced for separation of glucose, lactic acid and acetic acid ternary-mixture. This work focuses on exploring the feasibility of the proposed process theoretically and experimentally. Firstly, the real 3F-ISMB model coupled with the transport dispersive model (TDM) and the Modified-Langmuir isotherm was established to build up the separation parameter plane. Subsequently, three operating conditions were selected from the plane to run the 3F-ISMB unit. The experimental results were used to verify the model. Afterwards, the influences of the various flow rates on the separation performances were investigated systematically by means of the validated 3F-ISMB model. The intermittent-retained component lactic acid was finally obtained with the purity of 98.5%, recovery of 95.5% and the average concentration of 38 g/L. The proposed 3F-ISMB process can efficiently separate the mixture with low selectivity into three fractions. Copyright © 2018 Elsevier B.V. All rights reserved.

Experimental evaluation of the effect of a modified port-location mode on the performance of a three-zone simulated moving-bed process for the separation of valine and isoleucine.

PubMed

Park, Chanhun; Nam, Hee-Geun; Kim, Pung-Ho; Mun, Sungyong

2014-06-01

The removal of isoleucine from valine has been a key issue in the stage of valine crystallization, which is the final step in the valine production process in industry. To address this issue, a three-zone simulated moving-bed (SMB) process for the separation of valine and isoleucine has been developed previously. However, the previous process, which was based on a classical port-location mode, had some limitations in throughput and valine product concentration. In this study, a three-zone SMB process based on a modified port-location mode was applied to the separation of valine and isoleucine for the purpose of making a marked improvement in throughput and valine product concentration. Computer simulations and a lab-scale process experiment showed that the modified three-zone SMB for valine separation led to >65% higher throughput and >160% higher valine concentration compared to the previous three-zone SMB for the same separation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Standing wave design and experimental validation of a tandem simulated moving bed process for insulin purification.

PubMed

Xie, Yi; Mun, Sungyong; Kim, Jinhyun; Wang, Nien-Hwa Linda

2002-01-01

A tandem simulated moving bed (SMB) process for insulin purification has been proposed and validated experimentally. The mixture to be separated consists of insulin, high molecular weight proteins, and zinc chloride. A systematic approach based on the standing wave design, rate model simulations, and experiments was used to develop this multicomponent separation process. The standing wave design was applied to specify the SMB operating conditions of a lab-scale unit with 10 columns. The design was validated with rate model simulations prior to experiments. The experimental results show 99.9% purity and 99% yield, which closely agree with the model predictions and the standing wave design targets. The agreement proves that the standing wave design can ensure high purity and high yield for the tandem SMB process. Compared to a conventional batch SEC process, the tandem SMB has 10% higher yield, 400% higher throughput, and 72% lower eluant consumption. In contrast, a design that ignores the effects of mass transfer and nonideal flow cannot meet the purity requirement and gives less than 96% yield.

Microalgal growth in municipal wastewater treated in an anaerobic moving bed biofilm reactor.

PubMed

Hultberg, Malin; Olsson, Lars-Erik; Birgersson, Göran; Gustafsson, Susanne; Sievertsson, Bertil

2016-05-01

Nutrient removal from the effluent of an anaerobic moving bed biofilm reactor (AnMBBR) treated with microalgae was evaluated. Algal treatment was highly efficient in removal of nutrients and discharge limits were met after 3days. Extending the cultivation time from 3 to 5days resulted in a large increase in biomass, from 233.3±49.3 to 530.0±72.1mgL(-1), despite nutrients in the water being exhausted after 3days (ammonium 0.04mgL(-1), orthophosphate <0.05mgL(-1)). Biomass productivity, lipid content and quality did not differ in microalgal biomass produced in wastewater sampled before the AnMBBR. The longer cultivation time resulted in a slight increase in total lipid concentration and a significant decrease in linolenic acid concentration in all treatments. Differences were observed in chemical oxygen demand, which decreased after algal treatment in wastewater sampled before the AnMBBR whereas it increased after algal treatment in the effluent from the AnMBBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

High efficiency power generation from coal and wastes utilizing high temperature air combustion technology (Part 1: Performance of pebble bed gasifier for coal and wastes)

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

Kosaka, Hitoshi; Iwahashi, Takashi; Yoshida, Nobuhiro

1998-07-01

A new concept of a gasifier for coal and wastes is proposed where entrained bed and fixed pebble bed are combined. Main features of this pebble bed gasifier are high efficiency molten slag capture, high efficiency gasification and compactness. Coal and RFD combustion experiments using the pebble bed gasifier demonstrated high efficiency capture and continuous extraction of molten slag as well as complete char combustion with extra ordinarily short residence time of pulverized coal and crushed RDF at the temperature level of about 1,500 C within the pebble bed. Durability tests using high temperature electric furnace has shown that highmore » density alumna is a good candidate for pebble material.« less

Peering inside the granular bed: illuminating feedbacks between bed-load transport and bed-structure evolution

NASA Astrophysics Data System (ADS)

Houssais, M.; Jerolmack, D. J.; Martin, R. L.

2013-12-01

The threshold of motion is perhaps the most important quantity to determine for understanding rates of bed load transport, however it is a moving target. Decades of research show that it changes in space and in time within a river, and is highly variable among different systems; however, these differences are not mechanistically understood. Recent researchers have proposed that the critical Shields stress is strongly dependent on the local configuration of the sediment bed [Frey and Church, 2011]. Critical Shields stress has been observed to change following sediment-transporting flood events in natural rivers [e.g., Turowski et al., 2011], while small-scale laboratory experiments have produced declining bed load transport rates associated with slow bed compaction [Charru et al., 2004]. However, no direct measurements have been made of the evolving bed structure under bed load transport, so the connection between granular controls and the threshold of motion remains uncertain. A perspective we adopt is that granular effects determine the critical Shields stress, while the fluid supplies a distribution of driving stresses. In order to isolate the granular effect, we undertake laminar bed load transport experiments using plastic beads sheared by a viscous oil in a small, annular flume. The fluid and beads are refractive index matched, and the fluid impregnated with a fluorescing powder. When illuminated with a planar laser sheet, we are able to image slices of the granular bed while also tracking the overlying sediment transport. We present the first results showing how bed load transport influences granular packing, and how changes in packing influence the threshold of motion to feed back on bed load transport rates. This effect may account for much of the variability observed in the threshold of motion in natural streams, and by extension offers a plausible explanation for hysteresis in bed load transport rates observed during floods. Charru, F., H. Mouilleron, and O. Eiff, Erosion and deposition of particles on a bed sheared by a viscous flow, Journal of Fluid Mech., 519, 55-80, 2004 Frey, P. and Church, M. (2011), Bedload: a granular phenomenon. Earth Surf. Process. Landforms, 36: 58-69. doi: 10.1002/esp.2103 Turowski, J. M., A. Badoux, and D. Rickenmann (2011), Start and end of bedload transport in gravel-bed streams, Geophys. Res. Lett., 38, L04401, doi:10.1029/2010GL046558.

Advanced expander test bed program

NASA Technical Reports Server (NTRS)

Masters, A. I.; Mitchell, J. C.

1991-01-01

The Advanced Expander Test Bed (AETB) is a key element in NASA's Chemical Transfer Propulsion Program for development and demonstration of expander cycle oxygen/hydrogen engine technology component technology for the next space engine. The AETB will be used to validate the high-pressure expander cycle concept, investigate system interactions, and conduct investigations of advanced missions focused components and new health monitoring techniques. The split-expander cycle AETB will operate at combustion chamber pressures up to 1200 psia with propellant flow rates equivalent to 20,000 lbf vacuum thrust.

Fully industrialised single photon avalanche diodes

NASA Astrophysics Data System (ADS)

Pellegrini, S.; Rae, B.

2017-05-01

Single Photon Avalanche diodes (SPADs) were first realized more than five decades ago[1][1], and have now been industrialized for mass production in the 130 nm CMOS technology node by STMicroelectronics (STM). In this paper we present the latest STM SPAD with an excellent NIR photon detection probability (>5% at 850nm), a dark count rate median of 100 cps at room temperature and a low breakdown voltage of 14.2V. The dead time of the SPAD is approximately 25 ns, leading to a maximum count rate of 40 Mcps. Thanks to the 130 nm gate length of the CMOS technology used and the associated high digital gate density, complex digital signal processing can be implemented allowing fully integrated systems to be realized. The low bias required by the SPAD makes it possible for voltage generation to be achieved on-chip (e.g. charge pumped). We introduce our first generation time-of-flight system (VL6180) based on the STM SPAD technology, which is capable of ranging up to 60 cm in 60 ms. Ranging capabilities and accuracy are measured using a set of moving targets with reflectance of 5%, 17% and 88% in a fully automated test bed. To the best of our knowledge this was the first high volume SPAD-based device. To our knowledge this is the first time details of SPAD performance over production volumes and lifetime have been presented.

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM

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

Wei-Ping Pan; Andy Wu; John T. Riley

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period October 1, 2004 through December 31, 2004. The following tasks have been completed. First, the renovation of the new Combustion Laboratory and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building have proceeded well. Second, the detailed design of supporting and hanging structures for the CFBC was completed. Third, the laboratory-scale simulated fluidized-bed facility was modified after completing a series of pretests. The two problems identified during the pretest were solved.more » Fourth, the carbonization of chicken waste and coal was investigated in a tube furnace and a Thermogravimetric Analyzer (TGA). The experimental results from this study are presented in this report. Finally, the proposed work for the next quarter has been outlined in this report.« less

Life-finding detector development at NASA GSFC using a custom H4RG test bed

NASA Astrophysics Data System (ADS)

Mosby, Gregory; Rauscher, Bernard; Kutyrev, Alexander

2018-01-01

Chemical species associated with life, called biosignatures, should be visible in exoplanet atmospheres with larger space telescopes. These signals will be faint and require very low noise (~e-) detectors to robustly measure. At NASA Goddard we are developing a single detector H4RG test bed to characterize and identify potential technology developments needed for the next generation's large space telescopes. The vacuum and cryogenic test bed will include near infrared light sources from integrating spheres using a motorized shutter. The detector control and readout will be handled by a Leach controller. Detector cables have been manufactured and test planning has begun. Planned tests include testing minimum read noise capabilities, persistence mitigation strategies using long wavelength light, and measuring intrapixel variation which might affect science goals of future missions. In addition to providing a means to identify areas of improvement in detector technology, we hope to use this test bed to probe some fundamental physics of these infrared arrays.

Improvement of the performances of a tandem simulated moving bed chromatography by controlling the yield level of a key product of the first simulated moving bed unit.

PubMed

Mun, Sungyong; Wang, Nien-Hwa Linda

2017-03-10

One of the trustworthy processes for ternary separation is a tandem simulated moving bed (SMB) process, which consists of two subordinate four-zone SMB units (Ring I and Ring II). To take full advantage of a tandem SMB as a means of recovering all three products with high purities and high economical efficiency, it is important to understand how the separation condition in Ring II is affected by that in Ring I, and further to reflect such point in the stage of designing a tandem SMB. In regard to such issue, it was clarified in this study that the Ring I factors affecting the Ring II condition could be represented by the yield level of a key product of Ring I (Y key RingI ). As the Y key RingI level became higher, the amount of the Ring I key-product that was reloaded into Ring II was reduced, which affected favorably the Ring II separation condition. On the other hand, the higher Y key RingI level caused a larger dilution for the stream from Ring I to Ring II, which affected adversely the Ring II separation condition. As a result, a minimum in the desorbent usage of a tandem SMB occurred at the Y key RingI level where the two aforementioned factors could be balanced with each other. If such an optimal Y key RingI level was adopted, the desorbent usage could be reduced by up to 25%. It was also found that as the throughput of a tandem SMB became higher, the factor related to the migration of the Ring I key-product into Ring II was more influential in the performances of a tandem SMB than the factor related to the dilution of the stream from Ring I to Ring II. Copyright © 2016 Elsevier B.V. All rights reserved.

Space station propulsion technology

NASA Technical Reports Server (NTRS)

Briley, G. L.

1986-01-01

The progress on the Space Station Propulsion Technology Program is described. The objectives are to provide a demonstration of hydrogen/oxygen propulsion technology readiness for the Initial Operating Capability (IOC) space station application, specifically gaseous hydrogen/oxygen and warm hydrogen thruster concepts, and to establish a means for evolving from the IOC space station propulsion to that required to support and interface with advanced station functions. The evaluation of concepts was completed. The accumulator module of the test bed was completed and, with the microprocessor controller, delivered to NASA-MSFC. An oxygen/hydrogen thruster was modified for use with the test bed and successfully tested at mixture ratios from 4:1 to 8:1.

Seismogenic rotational slumps and translational glides in pelagic deep-water carbonates. Upper Tithonian-Berriasian of Southern Tethyan margin (W Sicily, Italy)

NASA Astrophysics Data System (ADS)

Basilone, Luca

2017-07-01

Soft-sediment deformation structures (SSDSs), which reflect sediment mobilization processes, are helpful to identify punctual events of paleoenvironmental stresses. In the upper Tithonian-Berriasian calpionellid pelagic limestone of the Lattimusa Fm. outcropping in the Barracù section (W Sicily), paleoenvironmental restoration reveals the occurrence of a deep-water flat basin, characterised by undeformed planar bedding, laterally passing to a gentle slope where the deformed horizons alternate with undeformed beds. Here, two types of gravity slides have been differentiated on the basis of different kinds of SSDSs, brittle deformation, involved lithofacies, geometry and morphology. Type 1 slump sheets, involving marl-limestone couplets, are characterised by chaotic stratification, truncated beds, recumbent folds, tension gashes, clastic dikes and small-scale listric normal faults and thrusts. They moved downslope as a rotational slump, displaying the typical wedge-shaped morphology, becoming thicker toe-wards. Type 2 slump sheets, involving bed packages of lime mudstone, are characterised by arcuate slump scars developing downwards as listric normal faults, associated with rotational beds and bulging. Displaying tabular geometries, they moved coherently along an overall bedding parallel detachment surface as a translational glide characterised by sediment creep. Regional geology indicates that the basin (Sicanian), bordered by a stepped carbonate platform, was affected by synsedimentary tectonics throughout the Mesozoic. The synsedimentary extensional tectonics that affect the Upper Triassic-Jurassic deposits with steeped normal faults, causing tilt-block and instability of the seafloor through fluidization processes, triggered the rotational slumps of the lower portion of the section. Seismic shocks, induced by outside sector tectonics, like those recorded in the adjacent Busambra stepped carbonate platform margin, triggered the rotational slumps that are not related to local-scale faults. To explain the translational glides of the upper portion of the section, the aforementioned outside sector earthquakes produced instability of the sea-floor through thixotropy of marls. In this case, the driving forces (i.e., gravitational) were favoured by the uplifting trend that is well recorded in the Southern Tethyan continental margin. We suggest that the various early deformations represent rotational slump and sediment creep that may be characteristic for slump structures in pelagic carbonates, depending on the involved lithologies (i.e., paleoenvironmental setting) and the intensity/distance of the trigger mechanism (i.e., earthquake epicentre).

A 34-meter VAWT (Vertical Axis Wind Turbine) point design

NASA Astrophysics Data System (ADS)

Ashwill, T. D.; Berg, D. E.; Dodd, H. M.; Rumsey, M. A.; Sutherland, H. J.; Veers, P. S.

The Wind Energy Division at Sandia National Laboratories recently completed a point design based on the 34-m Vertical Axis Wind Turbine (VAWT) Test Bed. The 34-m Test Bed research machine incorporates several innovations that improve Darrieus technology, including increased energy production, over previous machines. The point design differs minimally from the Test Bed; but by removing research-related items, its estimated cost is substantially reduced. The point design is a first step towards a Test-Bed-based commercial machine that would be competitive with conventional sources of power in the mid-1990s.

Hydrologic environment of the Silurian salt deposits in parts of Michigan, Ohio, and New York

USGS Publications Warehouse

Norris, Stanley E.

1978-01-01

The aggregate thickness of evaporites (salt, gypsum, and anhydrite) in the Silurian Salina sequence in Michigan exceeds 1200 feet in areas near the periphery of the Michigan basin, where the salt beds are less than 3000 feet below land surface. In northeast Ohio the aggregate thickness of salt beds is as much as 200 feet in places, and in western New York it is more than 500 feet, where th beds are less than 3000 feet deep. The salt-bearing rocks dip regionally on the order of 50 feet per mile; those in Michigan dip toward the center of the Michigan basin, and those in Ohio and New York, in the Appalachian basin, dip generally southward. The rocks in both basins thicken downdip. Minor folds and faults occur in the salt-bearing rocks in all three states. Some of this defrmation has been attenuated or absorbed bo the salt beds. Occuring near the middle of thick sedimentary sequences, the salt beds are bounded aboe and below by beds containing water having dissolved-solids concentrations several times that seawter. The brines occur commonly in discrete zones of high permeability at specific places in the stratigraphic sequence. In northeast Ohio two prominent brine zones are recognized by the driller, the Devonian Oriskany Sandstone, or 'first water' zone, above the Salina Formation, and the Newburg or 'second water' zone below the Salina. In each aquifer there is a vertical component of hydraulic head, but little brine probably moves through the salt beds because their permeability is extremely low. Also, ther is little evidence of dissolution of the salt in areas distant from the outcrop, suggesting that if brine does move through the salt, movement is at a slow enough rate so that, in combination with the saturated or near-saturated condition of the water, it precludes significant dissolution. Principal brine movement is probably in the permeable zones in the direction of the hydraulic gradient. Two areas in Michigan and one area each in Ohio and New York appear suitable for additional investigation of salt beds for purposes radioactive waste disposal. One of the Michigan areas is in the northern part of the southern peninsula, in Presque Isle and Alpena Counties; the other is in the southern part of the southern peninsula, in Oakland, Macomb, and St. Clair Counties (fig. 3). In northeast Ohio the area that appears to be suitable for investigation includes most of the eastern half of Lake County and extends eastward into Ashtabula County and southward into Geauga County. In western New York conditions may warrant additional investigation in Schuyler, Tompkins, and western Cortland Counties.

COSTS FOR ADVANCED COAL COMBUSTION TECHNOLOGIES

EPA Science Inventory

The report gives results of an evaluation of the development status of advanced coal combustion technologies and discusses the preparation of performance and economic models for their application to electric utility plants. he technologies addressed were atmospheric fluidized bed...

Beyond the threshold for motion: river channel geometry and grain size reflect sediment supply

NASA Astrophysics Data System (ADS)

Pfeiffer, A.; Finnegan, N. J.; Willenbring, J. K.

2016-12-01

In many gravel-bedded rivers, floods that fill the ch­­annel banks create just enough shear stress to move the median-sized gravel particles on the bed surface (D50). Because this observation is common and is supported by theory, the coincidence of bankfull flow and the incipient motion of D50 has become a­­ commonly employed assumption. However, not all natural gravel channels actually conform to this simple relationship; some channels maintain bankfull stresses far in excess of the critical stress required to initiate sediment transport. We use a database of >300 gravel-bedded rivers and >600 10Be-derived erosion rates from across North America to explore the hypothesis that sediment supply drives the magnitude of bankfull shear stress relative to the critical stress required to mobilize the median bed surface grain size. We find that the ratio of bankfull to critical stress is significantly higher in West Coast river reaches (2.47, n= 84) than in river reaches in the rest of the continent (1.03, n = 245). This pattern parallels trends in erosion rates (and hence sediment supplies). Supporting our hypothesis, we find a significant correlation between upstream erosion rate and local τ*bf/τ*c at sites where this comparison is possible. Our analysis reveals a decrease in bed surface armoring with increasing τ*bf/τ*c, suggesting that channels accommodate changes in sediment supply through adjustments in bed surface grain size, as predicted through numerical modeling. Our findings demonstrate that sediment supply is encoded in the bankfull hydraulic geometry of gravel-bedded channels through its control on bed surface grain size.

Guaranteeng Of Ecological Safety Of Wastewater Tretment By Phytoremediation

NASA Astrophysics Data System (ADS)

Nefedieva, E. E.; Kartushina, Yu N.; Zheltobryukhov, V. F.; Sevriukova, G. A.; Baybakova, E. V.

2017-01-01

This article is devoted to the experimental identification of the copper ions (II) uptake by the remediation plant. Wheat and barley were used as plants for phytoremediation. They were cultivated in the aqueous culture on the Hellriegel nutritive medium prepared without phosphorus. The copper was dissolved in the medium in the concentration 0 mg/l (control variant), 0.5 mg/l, 1.0 mg/l, 2.5 mg/l, 5 mg/l, 10 mg/l, 20 mg/l. The concentrations of the copper were identified in solutions by the ion meter in 2 weeks of cultivation. The moving arrangement with a plant as a biological bed is elaborated for phytofiltration. That is a technology for decontamination and final treatment of the wastewater from pollutants using plants. Particularly it is possible to remove ions of heavy metals. The device will be inexpensive, simple and easy for exploitation at the enterprise. It is offered to complete standard rectangular settler by the mentioned device.

KSC-2012-4107

NASA Image and Video Library

2012-07-31

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, is being moved out of its checkout building for a short trip to a launch position at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/Dimitri Gerondidakis

KSC-2012-4106

NASA Image and Video Library

2012-07-31

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, is being moved out of its checkout building for a short trip to a launch position at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/Dimitri Gerondidakis

KSC-2012-4031

NASA Image and Video Library

2012-07-27

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, has been moved into a building at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser

KSC-2012-4032

NASA Image and Video Library

2012-07-27

CAPE CANAVERAL, Fla. - NASA's Morpheus lander, a vertical test bed vehicle, has been moved into a building at the Shuttle Landing Facility, or SLF, at the Kennedy Space Center in Florida. Morpheus is designed to demonstrate new green propellant propulsion systems and autonomous landing and an Autonomous Landing and Hazard Avoidance Technology, or ALHAT, system. Checkout of the prototype lander has been ongoing at NASA’s Johnson Space Center in Houston in preparation for its first free flight. The SLF site will provide the lander with the kind of field necessary for realistic testing. Project Morpheus is one of 20 small projects comprising the Advanced Exploration Systems, or AES, program in NASA’s Human Exploration and Operations Mission Directorate. AES projects pioneer new approaches for rapidly developing prototype systems, demonstrating key capabilities and validating operational concepts for future human missions beyond Earth orbit. For more information on Project Morpheus, visit http://www.nasa.gov/centers/johnson/exploration/morpheus/index.html Photo credit: NASA/ Charisse Nahser

Multiphase flow simulations of a moving fluidized bed regenerator in a carbon capture unit

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

Sarkar, Avik; Pan, Wenxiao; Suh, Dong-Myung

2014-10-01

To accelerate the commercialization and deployment of carbon capture technologies, computational fluid dynamics (CFD)-based tools may be used to model and analyze the performance of carbon capture devices. This work presents multiphase CFD-based flow simulations for the regeneration device responsible for extracting CO 2 from CO 2-loaded sorbent particles before the particles are recycled. The use of solid particle sorbents in this design is a departure from previously reported systems, where aqueous sorbents are employed. Another new feature is the inclusion of a series of perforated plates along the regenerator height. The influence of these plates on sorbent distribution ismore » examined for varying sorbent holdup, fluidizing gas velocity, and particle size. The residence time distribution of sorbents is also measured to classify the low regime as plug flow or well-mixed flow. The purpose of this work is to better understand the sorbent flow characteristics before reaction kinetics of CO 2 desorption can be implemented.« less

A New Dry Flue Gas Desulfurization Process-Underfeed Circulating Spouted Bed

NASA Astrophysics Data System (ADS)

Tao, M.; Jin, B. S.; Yang, Y. P.

Applying an underfeed system, the underfeed circulating spouted bed was designed as a desulfurization reactor. The main objective of the technology is to improve the mixing effect and distribution uniformity of solid particles, and therefore to advance the desulfurization efficiency and calcium utility. In this article, a series of experimental studies were conducted to investigate the fluidization behavior of the solid-gas two-phase flow in the riser. The results show that the technology can distinctly improve the distribution of gas velocity and particle flux on sections compared with the facefeed style. Analysis of pressure fluctuation signals indicates that the operation parameters have significant influence on the flow field in the reaction bed. The existence of injecting flow near the underfeed nozzle has an evident effect on strengthening the particle mixing.

Is there a Developed Oldowan A at Olduvai Gorge? A diachronic analysis of the Oldowan in Bed I and Lower-Middle Bed II at Olduvai Gorge, Tanzania.

PubMed

Proffitt, Tomos

2018-05-08

Debates regarding the validity of the Developed Oldowan as separate cultural facies within the Oldowan techno-complex have primarily concentrated on the Developed Oldowan B/Acheulean transition, with little attention paid to the validity of the Developed Oldowan A (DOA) as a valid technological differentiation. This study presents a diachronic technological analysis and comparison of Oldowan and DOA lithic assemblages from Olduvai Gorge, Tanzania, dated between 1.84 and 1.6 Ma, to test the validity of Leakey's original distinction between these two cultural facies. The results from this comparative analysis show very few technological differences between the lithic assemblages previously assigned to the DOA and Classic Oldowan. Significant diachronic variation in raw material availability and use is, however, identified between Bed I and Lower/Middle Bed II of Olduvai Gorge, which may go some way to explaining the originally perceived techno-cultural differences. The results suggest an increase in hominin knapping and percussive activities, as well as a clear ability to preferentially select high quality raw materials stratigraphically above Tuff IF. Technological innovation and complexity, however, does not seem to vary significantly between the Classic Oldowan and DOA assemblages. The results of this analysis along with similar studies from the wider eastern African region lead to the conclusion that the term Developed Oldowan A should no longer be used. Copyright © 2018 Elsevier Ltd. All rights reserved.

Identification of discontinuous sand pulses on the bed of the Colorado River in Grand Canyon

NASA Astrophysics Data System (ADS)

Mueller, E. R.; Grams, P. E.; Buscombe, D.; Topping, D. J.

2017-12-01

Decades of research on alluvial sandbars and sand transport on the Colorado River in Grand Canyon has contributed to in-depth understanding of the sand budget and lead to management actions designed to rebuild eroded sandbars. However, some basic, but difficult to address, questions about the processes and rates of sand movement through the system still limit our ability to predict geomorphic responses. The coarse fraction of the bed is heterogeneous and varies among boulders, cobble, gravel, and bedrock. Sand covers these substrates in patches of variable size and thickness, fills interstices to varying degrees, and forms mixed sand/coarse bed configurations such as linear stripes. Understanding the locations of sand accumulation, the quantities of sand contained in those locations, and the processes by which sand is exchanged among depositional locations is needed to predict the morphological response of sandbars to management actions, such as the controlled flood releases, and to predict whether sandbars are likely to increase or decrease in size over long (i.e. decadal) time periods. Here, we present evidence for the downstream translation of the sand component of tributary sediment inputs as discontinuous sand pulses. The silt and clay (mud) fraction of sediment introduced episodically by seasonal floods from tributary streams is transported entirely in suspension and moves through the 400 km series of canyons in a few days. The sand fraction of this sediment, which is transported on the bed and in suspension, moves downstream in sand pulses that we estimate range in length from a few km to tens of km. Owing to the complex geomorphic organization, the sand pulses are not detectable as coherent bed features; each individual sand pulse is comprised of many isolated storage locations, separated by rapids and riffles where sand cover is sparse. The presence of the sand pulses is inferred by the existence of alternating segments of sand accumulation and depletion computed from repeat maps of the channel. Improved understanding of the behavior of these sand pulses may be used to adjust the timing, magnitude, and duration of controlled floods to maximize potential for deposition on sandbars in different segments of the 450 km-long Grand Canyon.

Response of bed surface patchiness to reductions in sediment supply

NASA Astrophysics Data System (ADS)

Nelson, Peter A.; Venditti, Jeremy G.; Dietrich, William E.; Kirchner, James W.; Ikeda, Hiroshi; Iseya, Fujiko; Sklar, Leonard S.

2009-06-01

River beds are often arranged into patches of similar grain size and sorting. Patches can be distinguished into "free patches," which are zones of sorted material that move freely, such as bed load sheets; "forced patches," which are areas of sorting forced by topographic controls; and "fixed patches" of bed material rendered immobile through localized coarsening that remain fairly persistent through time. Two sets of flume experiments (one using bimodal, sand-rich sediment and the other using unimodal, sand-free sediment) are used to explore how fixed and free patches respond to stepwise reductions in sediment supply. At high sediment supply, migrating bed load sheets formed even in unimodal, sand-free sediment, yet grain interactions visibly played a central role in their formation. In both sets of experiments, reductions in supply led to the development of fixed coarse patches, which expanded at the expense of finer, more mobile patches, narrowing the zone of active bed load transport and leading to the eventual disappearance of migrating bed load sheets. Reductions in sediment supply decreased the migration rate of bed load sheets and increased the spacing between successive sheets. One-dimensional morphodynamic models of river channel beds generally are not designed to capture the observed variability, but should be capable of capturing the time-averaged character of the channel. When applied to our experiments, a 1-D morphodynamic model (RTe-bookAgDegNormGravMixPW.xls) predicted the bed load flux well, but overpredicted slope changes and was unable to predict the substantial variability in bed load flux (and load grain size) because of the migration of mobile patches. Our results suggest that (1) the distribution of free and fixed patches is primarily a function of sediment supply, (2) the dynamics of bed load sheets are primarily scaled by sediment supply, (3) channels with reduced sediment supply may inherently be unable to transport sediment uniformly across their width, and (4) cross-stream variability in shear stress and grain size can produce potentially large errors in width-averaged sediment flux calculations.

Forces on stationary particles in near-bed turbulent flows

NASA Astrophysics Data System (ADS)

Schmeeckle, Mark W.; Nelson, Jonathan M.; Shreve, Ronald L.

2007-06-01

In natural flows, bed sediment particles are entrained and moved by the fluctuating forces, such as lift and drag, exerted by the overlying flow on the particles. To develop a better understanding of these forces and the relation of the forces to the local flow, the downstream and vertical components of force on near-bed fixed particles and of fluid velocity above or in front of them were measured synchronously at turbulence-resolving frequencies (200 or 500 Hz) in a laboratory flume. Measurements were made for a spherical test particle fixed at various heights above a smooth bed, above a smooth bed downstream of a downstream-facing step, and in a gravel bed of similarly sized particles as well as for a cubical test particle and 7 natural particles above a smooth bed. Horizontal force was well correlated with downstream velocity and not correlated with vertical velocity or vertical momentum flux. The standard drag formula worked well to predict the horizontal force, but the required value of the drag coefficient was significantly higher than generally used to model bed load motion. For the spheres, cubes, and natural particles, average drag coefficients were found to be 0.76, 1.36, and 0.91, respectively. For comparison, the drag coefficient for a sphere settling in still water at similar particle Reynolds numbers is only about 0.4. The variability of the horizontal force relative to its mean was strongly increased by the presence of the step and the gravel bed. Peak deviations were about 30% of the mean force for the sphere over the smooth bed, about twice the mean with the step, and 4 times it for the sphere protruding roughly half its diameter above the gravel bed. Vertical force correlated poorly with downstream velocity, vertical velocity, and vertical momentum flux whether measured over or ahead of the test particle. Typical formulas for shear-induced lift based on Bernoulli's principle poorly predict the vertical forces on near-bed particles. The measurements suggest that particle-scale pressure variations associated with turbulence are significant in the particle momentum balance.

Forces on stationary particles in near-bed turbulent flows

USGS Publications Warehouse

Schmeeckle, M.W.; Nelson, J.M.; Shreve, R.L.

2007-01-01

In natural flows, bed sediment particles are entrained and moved by the fluctuating forces, such as lift and drag, exerted by the overlying flow on the particles. To develop a better understanding of these forces and the relation of the forces to the local flow, the downstream and vertical components of force on near-bed fixed particles and of fluid velocity above or in front of them were measured synchronously at turbulence-resolving frequencies (200 or 500 Hz) in a laboratory flume. Measurements were made for a spherical test particle fixed at various heights above a smooth bed, above a smooth bed downstream of a downstream-facing step, and in a gravel bed of similarly sized particles as well as for a cubical test particle and 7 natural particles above a smooth bed. Horizontal force was well correlated with downstream velocity and not correlated with vertical velocity or vertical momentum flux. The standard drag formula worked well to predict the horizontal force, but the required value of the drag coefficient was significantly higher than generally used to model bed load motion. For the spheres, cubes, and natural particles, average drag coefficients were found to be 0.76, 1.36, and 0.91, respectively. For comparison, the drag coefficient for a sphere settling in still water at similar particle Reynolds numbers is only about 0.4. The variability of the horizontal force relative to its mean was strongly increased by the presence of the step and the gravel bed. Peak deviations were about 30% of the mean force for the sphere over the smooth bed, about twice the mean with the step, and 4 times it for the sphere protruding roughly half its diameter above the gravel bed. Vertical force correlated poorly with downstream velocity, vertical velocity, and vertical momentum flux whether measured over or ahead of the test particle. Typical formulas for shear-induced lift based on Bernoulli's principle poorly predict the vertical forces on near-bed particles. The measurements suggest that particle-scale pressure variations associated with turbulence are significant in the particle momentum balance. Copyright 2007 by the American Geophysical Union.

Network operating system focus technology

NASA Technical Reports Server (NTRS)

1985-01-01

An activity structured to provide specific design requirements and specifications for the Space Station Data Management System (DMS) Network Operating System (NOS) is outlined. Examples are given of the types of supporting studies and implementation tasks presently underway to realize a DMS test bed capability to develop hands-on understanding of NOS requirements as driven by actual subsystem test beds participating in the overall Johnson Space Center test bed program. Classical operating system elements and principal NOS functions are listed.

Heat transfer and technological investigations on mixed beds of beryllium and Li 4SiO 4 pebbles

NASA Astrophysics Data System (ADS)

Dalle Donne, M.; Goraieb, A.; Huber, R.; Schmitt, B.; Schumacher, G.; Sordon, G.; Weisenburger, A.

1994-09-01

For the European BOT DEMO solid breeder blanket design the use of mixtures of 2 mm beryllium and 0.1-0.2 mm Li 4SiO 4 pebbles with and without 0.1-0.2 mm beryllium pebbles has been proposed. A series of heat transfer and technological investigations are being performed for these pebbles. Namely: (a) Measurements of the thermal conductivity and of the wall heat transfer coefficient of a 2 mm Be pebble bed, of a bed with 2 mm Be plus 0.1-0.2 mm Li 4SiO 4 pebbles and of a bed with 2 mm Be pebbles plus 0.1-0.2 mm Li 4SiO 4 and Be pebbles. (b) Thermal cycle tests of mixed beds of Li 4SiO 4 and beryllium pebbles; during these tests the pressure drop across the bed of the helium purging flow is measured. (c) Annealing tests at 650°C of the Li 4SiO 4 pebbles with and without the beryllium pebbles. (d) Measurement of the failure loads of the Li 4SiO 4 pebbles before and after annealing. Tests (a) and (b) have been performed for bigger Li 4SiO 4 pebbles (0.3-0.6 mm) as well. The results of the experiments are reported in the paper.

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

Burge, S.W.

Erosion has been identified as one of the significant design issues in fluid beds. A cooperative R&D venture of industry, research, and government organizations was recently formed to meet the industry need for a better understanding of erosion in fluid beds. Research focussed on bed hydrodynamics, which are considered to be the primary erosion mechanism. As part of this work, ANL developed an analytical model (FLUFIX) for bed hydrodynamics. Partial validation was performed using data from experiments sponsored by the research consortium. Development of a three-dimensional fluid bed hydrodynamic model was part of Asea-Babcock`s in-kind contribution to the R&D venture.more » This model, FORCE2, was developed by Babcock & Wilcox`s Research and Development Division existing B&W program and on the gas-solids modeling and was based on an existing B&W program and on the gas-solids modeling technology developed by ANL and others. FORCE2 contains many of the features needed to model plant size beds and, therefore can be used along with the erosion technology to assess metal wastage in industrial equipment. As part of the development efforts, FORCE2 was partially validated using ANL`s two-dimensional model, FLUFIX, and experimental data. Time constraints as well as the lack of good hydrodynamic data, particularly at the plant scale, prohibited a complete validation of FORCE2. This report describes this initial validation of FORCE2.« less

Atmospheric volatilization and distribution of (Z)- and (E)-1,3-dichloropropene in field beds with and without plastic covers.

PubMed

Thomas, John E; Allen, L Hartwell; McCormack, Leslie A; Vu, Joseph C; Dickson, Donald W; Ou, Li-Tse

2004-01-01

The fumigant 1,3-dichloropropene (1,3-D) is considered to be a potential replacement for methyl bromide when methyl bromide is phased out in 2005. This study on surface emissions and subsurface diffusion of 1,3-D in a Florida sandy soil was conducted in field beds with or without plastic covers. After injection of the commercial fumigant Telone II by conventional chisels to field beds at 30cm depth which were covered with polyethylene film (PE), virtually impermeable film, or no cover (bare), (Z)- and (E)-1,3-D rapidly diffused upward. Twenty hours after injection, majority of (Z)- and (E)-1,3-D had moved upward from 30 cm depth to the layer of 5-20 cm depth. Downward movement of the two isomers in the beds with or without a plastic cover was not significant. (Z)-1,3-D diffused more rapidly than (E)-1,3-D. Virtually impermeable films (VIF) had a good capacity to retain (Z)- and (E)-1,3-D in soil pore air space. Vapor concentrations of the two isomers in the shallow subsurface of the field bed covered with VIF were greater than that in the two beds covered with polyethylene film (PE) or no cover (bare). In addition, VIF cover provided more uniform distribution of (Z)- and (E)-1,3-D in shallow subsurface than PE cover or no cover. Virtually impermeable film also had a better capability to retard surface emissions of the two isomers from soil in field beds than PE cover or no cover.

Interplay between spatially explicit sediment sourcing, hierarchical river-network structure, and in-channel bed material sediment transport and storage dynamics

NASA Astrophysics Data System (ADS)

Czuba, Jonathan A.; Foufoula-Georgiou, Efi; Gran, Karen B.; Belmont, Patrick; Wilcock, Peter R.

2017-05-01

Understanding how sediment moves along source to sink pathways through watersheds—from hillslopes to channels and in and out of floodplains—is a fundamental problem in geomorphology. We contribute to advancing this understanding by modeling the transport and in-channel storage dynamics of bed material sediment on a river network over a 600 year time period. Specifically, we present spatiotemporal changes in bed sediment thickness along an entire river network to elucidate how river networks organize and process sediment supply. We apply our model to sand transport in the agricultural Greater Blue Earth River Basin in Minnesota. By casting the arrival of sediment to links of the network as a Poisson process, we derive analytically (under supply-limited conditions) the time-averaged probability distribution function of bed sediment thickness for each link of the river network for any spatial distribution of inputs. Under transport-limited conditions, the analytical assumptions of the Poisson arrival process are violated (due to in-channel storage dynamics) where we find large fluctuations and periodicity in the time series of bed sediment thickness. The time series of bed sediment thickness is the result of dynamics on a network in propagating, altering, and amalgamating sediment inputs in sometimes unexpected ways. One key insight gleaned from the model is that there can be a small fraction of reaches with relatively low-transport capacity within a nonequilibrium river network acting as "bottlenecks" that control sediment to downstream reaches, whereby fluctuations in bed elevation can dissociate from signals in sediment supply.

Advanced Turbine Technology Applications Project (ATTAP)

NASA Technical Reports Server (NTRS)

1989-01-01

ATTAP activities during the past year were highlighted by an extensive materials assessment, execution of a reference powertrain design, test-bed engine design and development, ceramic component design, materials and component characterization, ceramic component process development and fabrication, component rig design and fabrication, test-bed engine fabrication, and hot gasifier rig and engine testing. Materials assessment activities entailed engine environment evaluation of domestically supplied radial gasifier turbine rotors that were available at the conclusion of the Advanced Gas Turbine (AGT) Technology Development Project as well as an extensive survey of both domestic and foreign ceramic suppliers and Government laboratories performing ceramic materials research applicable to advanced heat engines. A reference powertrain design was executed to reflect the selection of the AGT-5 as the ceramic component test-bed engine for the ATTAP. Test-bed engine development activity focused on upgrading the AGT-5 from a 1038 C (1900 F) metal engine to a durable 1371 C (2500 F) structural ceramic component test-bed engine. Ceramic component design activities included the combustor, gasifier turbine static structure, and gasifier turbine rotor. The materials and component characterization efforts have included the testing and evaluation of several candidate ceramic materials and components being developed for use in the ATTAP. Ceramic component process development and fabrication activities were initiated for the gasifier turbine rotor, gasifier turbine vanes, gasifier turbine scroll, extruded regenerator disks, and thermal insulation. Component rig development activities included combustor, hot gasifier, and regenerator rigs. Test-bed engine fabrication activities consisted of the fabrication of an all-new AGT-5 durability test-bed engine and support of all engine test activities through instrumentation/build/repair. Hot gasifier rig and test-bed engine testing activities were performed.

The sleep and technology use of Americans: findings from the National Sleep Foundation's 2011 Sleep in America poll.

PubMed

Gradisar, Michael; Wolfson, Amy R; Harvey, Allison G; Hale, Lauren; Rosenberg, Russell; Czeisler, Charles A

2013-12-15

To describe the technology use and sleep quality of Americans, and the unique association between technology use and sleep disturbances. Interviews were conducted via random digit dialing (N = 750) or the Internet (N = 758). 1,508 Americans (13-64 years old, 50% males) matched to 2009 U.S. Census data provided complete interviews. The sample was further divided into adolescents (13-18 years, N = 171), young adults (19-29 years, N = 293), middle-aged adults (30-45 years, N = 469), and older adults (46-64 years, N = 565) to contrast different generations' technology use. Participants answered a 47-item semi-structured survey, including questions about their sleep habits, and the presence and use of technology in the hour before bed in the past 2 weeks. Nine of 10 Americans reported using a technological device in the hour before bed (e.g., TVs the most popular; 60%). However, those under 30 years of age were more likely to use cell phones (72% of adolescents, 67% of young adults) than those over 30 years (36% of middle-aged, and 16% of older adults). Young adults' sleep patterns were significantly later than other age groups on both weekdays and weekend nights. Unlike passive technological devices (e.g., TV, mp3 music players), the more interactive technological devices (i.e., computers/laptops, cell phones, video game consoles) used in the hour before bed, the more likely difficulties falling asleep (β = 9.4, p < 0.0001) and unrefreshing sleep (β = 6.4, p < 0.04) were reported. Technology use near bedtime is extremely prevalent in the United States. Among a range of technologies, interactive technological devices are most strongly associated with sleep complaints.

Advanced Turbine Technology Applications Project (ATTAP) 1993 annual report

NASA Technical Reports Server (NTRS)

1994-01-01

This report summarizes work performed by AlliedSignal Engines, a unit of AlliedSignal Aerospace Company, during calendar year 1993, toward development and demonstration of structural ceramic technology for automotive gas turbine engines. This work was performed for the U.S. Department of Energy (DOE) under National Aeronautics and Space Administration (NASA) Contract DEN3-335, Advanced Turbine Technology Applications Project (ATFAP). During 1993, the test bed used to demonstrate ceramic technology was changed from the AlliedSignal Engines/Garrett Model AGT101 regenerated gas turbine engine to the Model 331-200(CT) engine. The 331-200(CT) ceramic demonstrator is a fully-developed test platform based on the existing production AlliedSignal 331-200(ER) gas turbine auxiliary power unit (APU), and is well suited to evaluating ceramic turbine blades and nozzles. In addition, commonality of the 331-200(CT) engine with existing gas turbine APU's in commercial service provides the potential for field testing of ceramic components. The 1993 ATTAP activities emphasized design modifications of the 331-200 engine test bed to accommodate ceramic first-stage turbine nozzles and blades, fabrication of the ceramic components, ceramic component proof and rig tests, operational tests of the test bed equipped with the ceramic components, and refinement of critical ceramic design technologies.

Next Generation Life Support Project Status

NASA Technical Reports Server (NTRS)

Barta, Daniel J.; Chullen, Cinda; Pickering, Karen D.; Cox, Marlon; Towsend, Neil; Campbell, Colin; Flynn, Michael; Wheeler, Raymond

2012-01-01

Next Generation Life Support (NGLS) is one of several technology development projects sponsored by NASA s Game Changing Development Program. The NGLS Project is developing life support technologies (including water recovery and space suit life support technologies) needed for humans to live and work productively in space. NGLS has three project tasks: Variable Oxygen Regulator (VOR), Rapid Cycle Amine (RCA) swing bed, and Alternative Water Processor (AWP). The RCA swing bed and VOR tasks are directed at key technology needs for the Portable Life Support System (PLSS) for an Advanced Extravehicular Mobility Unit, with focus on test article development and integrated testing in an Advanced PLSS in cooperation with the Advanced Extra Vehicular Activity (EVA) Project. An RCA swing-bed provides integrated carbon dioxide removal and humidity control that can be regenerated in real time during an EVA. The VOR technology will significantly increase the number of pressure settings available to the space suit. Current space suit pressure regulators are limited to only two settings whereas the adjustability of the advanced regulator will be nearly continuous. The AWP effort, based on natural biological processes and membrane-based secondary treatment, will result in the development of a system capable of recycling wastewater from sources expected in future exploration missions, including hygiene and laundry water. This paper will provide a status of technology development activities and future plans.

Health Occupations Curriculum. Skills for Nursing Assistant. Volume 3, Unit 8.

ERIC Educational Resources Information Center

Arizona State Dept. of Education, Phoenix.

Part of a health occupations program, this instructional unit contains 13 learning modules for use in training nursing assistants. Covered in the modules are (1) making beds, bathing patients, and measuring intake and output; (2) body mechanics, moving and lifting patients, range of motion exercises, and caring for patients in casts or traction;…

Get Kids Moving: Simple Activities To Build Gross-Motor Skills.

ERIC Educational Resources Information Center

Texas Child Care, 2003

2003-01-01

Highlights the importance of activities to build gross motor skills and provides hints for encouraging such activities. Specific areas of activities presented are: (1) running and jumping; (2) music games; (3) action games; (4) races; (5) bed sheets or parachutes; (6) hula hoops; (7) balls; (8) batting; (9) balance; and (10) creative movement. (SD)

Patient's breath controls comfort devices

NASA Technical Reports Server (NTRS)

Schrader, M.; Carpenter, B.; Nichols, C. D.

1972-01-01

Patient assist system for totally disabled persons was developed which permits a person, so paralyzed as to be unable to move, to activate by breathing, a call system to summon assistance, turn the page of a book, ajust his bed, or do any one of a number of other things. System consists of patient assist control and breath actuated switch.

Defining phases of bedload transport using piecewise regression

Treesearch

Sandra E. Ryan; Laurie S. Porth; C. A. Troendle

2002-01-01

Differences in the transport rate and size of bedload exist for varying levels of flow in coarse-grained channels. For gravel-bed rivers, at least two phases of bedload transport, with notably differing qualities, have been described in the literature. Phase I consists primarily of sand and small gravel moving at relatively low rates over a stable channel surface....

CONTINUOUS MICRO-SORTING OF COMPLEX WASTE PLASTICS PARTICLEMIXTURES VIA LIQUID-FLUIDIZED BED CLASSIFICATION (LFBC) FOR WASTE MINIMIZATIONAND RECYCLING

EPA Science Inventory

A fundamental investigation is proposed to provide a technical basis for the development of a novel, liquid-fluidized bed classification (LFBC) technology for the continuous separation of complex waste plastic mixtures for in-process recycling and waste minimization. Although ...

Electrical Capacitance Volume Tomography for the Packed Bed Reactor ISS Flight Experiment

NASA Technical Reports Server (NTRS)

Marashdeh, Qussai; Motil, Brian; Wang, Aining; Liang-Shih, Fan

2013-01-01

Fixed packed bed reactors are compact, require minimum power and maintenance to operate, and are highly reliable. These features make this technology a highly desirable unit operation for long duration life support systems in space. NASA is developing an ISS experiment to address this technology with particular focus on water reclamation and air revitalization. Earlier research and development efforts funded by NASA have resulted in two hydrodynamic models which require validation with appropriate instrumentation in an extended microgravity environment. To validate these models, the instantaneous distribution of the gas and liquid phases must be measured.Electrical Capacitance Volume Tomography (ECVT) is a non-invasive imaging technology recently developed for multi-phase flow applications. It is based on distributing flexible capacitance plates on the peripheral of a flow column and collecting real-time measurements of inter-electrode capacitances. Capacitance measurements here are directly related to dielectric constant distribution, a physical property that is also related to material distribution in the imaging domain. Reconstruction algorithms are employed to map volume images of dielectric distribution in the imaging domain, which is in turn related to phase distribution. ECVT is suitable for imaging interacting materials of different dielectric constants, typical in multi-phase flow systems. ECVT is being used extensively for measuring flow variables in various gas-liquid and gas-solid flow systems. Recent application of ECVT include flows in risers and exit regions of circulating fluidized beds, gas-liquid and gas-solid bubble columns, trickle beds, and slurry bubble columns. ECVT is also used to validate flow models and CFD simulations. The technology is uniquely qualified for imaging phase concentrations in packed bed reactors for the ISS flight experiments as it exhibits favorable features of compact size, low profile sensors, high imaging speed, and flexibility to fit around columns of various shapes and sizes. ECVT is also safer than other commonly used imaging modalities as it operates in the range of low frequencies (1 MHz) and does not radiate radioactive energy. In this effort, ECVT is being used to image flow parameters in a packed bed reactor for an ISS flight experiment.

Examination of wireless technology to improve nurse communication, response time to bed alarms, and patient safety.

PubMed

Guarascio-Howard, Linda

2011-01-01

A medical-surgical unit in a southwestern United States hospital examined the results of adding wireless communication technology to assist nurses in identifying patient bed status changes and enhancing team communication. Following the addition of wireless communication, response time to patient calls and the number of nurse-initiated communications were compared to pre-wireless calls and response time sampling period. In the baseline study, nurse-initiated communications and response time to patient calls were investigated for a team nursing model (Guarascio-Howard & Malloch, 2007). At this time, technology consisted of a nurse call system and telephones located at each decentralized nurse station and health unit coordinator (HUC) station. For this follow-up study, a wireless device was given to nurses and their team members following training on device use and privacy issues. Four registered nurses (RNs) were shadowed for 8 hours (32 hours total) before and after the introduction of the wireless devices. Data were collected regarding patient room visits, number of patient calls, bed status calls, response time to calls, and the initiator of the communication episodes. Follow-up study response time to calls significantly decreased (t-test p = .03). RNs and licensed practical nurses responded to bed status calls in less than 1 minute-62% of the 37 calls. Communication results indicated a significant shift (One Proportion Z Test) in RN-initiated communications, suggesting an enhanced ability to communicate with team members and to assist in monitoring patient status. Patient falls trended downward, although not significantly (p > .05), for a 6-month period of wireless technology use compared to the same period the previous year. The addition of a wireless device has advantages in team nursing, namely increasing communication with staff members and decreasing response time to patient and bed status calls. Limitations of the study included a change in caregiver team members and issues regarding wireless device and locator badge compliance. Administrative issues that arose during this field study included bed and cable maintenance, device battery charging, and the training of new and floating team members.

Movements of a Sphere Moving Over Smooth and Rough Inclines

NASA Astrophysics Data System (ADS)

Jan, Chyan-Deng

1992-01-01

The steady movements of a sphere over a rough incline in air, and over smooth and rough inclines in a liquid were studied theoretically and experimentally. The principle of energy conservation was used to analyze the translation velocities, rolling resistances, and drag coefficients of a sphere moving over the inclines. The rolling resistance to the movement of a sphere from the rough incline was presumed to be caused by collisions and frictional slidings. A varnished wooden board was placed on the bottom of an experimental tilting flume to form a smooth incline and a layer of spheres identical to the sphere moving over them was placed on the smooth wooden board to form a rough incline. Spheres used in the experiments were glass spheres, steel spheres, and golf balls. Experiments show that a sphere moving over a rough incline with negligible fluid drag in air can reach a constant translation velocity. This constant velocity was found to be proportional to the bed inclination (between 11 ^circ and 21^circ) and the square root of the sphere's diameter, but seemingly independent of the sphere's specific gravity. Two empirical coefficients in the theoretical expression of the sphere's translation velocity were determined by experiments. The collision and friction parts of the shear stress exerted on the interface between the moving sphere and rough incline were determined. The ratio of collision to friction parts appears to increase with increase in the bed inclination. These two parts seem to be of the same order of magnitude. The rolling resistances and the relations between the drag coefficient and Reynolds number for a sphere moving over smooth and rough inclines in a liquid, such as water or salad oil, were determined by a regression analysis based on experimental data. It was found that the drag coefficient for a sphere over the rough incline is larger than that for a sphere over the smooth incline, and both of which are much larger than that for a sphere in free fall. The relative magnitudes of the shear stresses due to drag, collision, and friction were also determined in terms of the Reynolds number.

Forecasting Daily Patient Outflow From a Ward Having No Real-Time Clinical Data

PubMed Central

Tran, Truyen; Luo, Wei; Phung, Dinh; Venkatesh, Svetha

2016-01-01

Background: Modeling patient flow is crucial in understanding resource demand and prioritization. We study patient outflow from an open ward in an Australian hospital, where currently bed allocation is carried out by a manager relying on past experiences and looking at demand. Automatic methods that provide a reasonable estimate of total next-day discharges can aid in efficient bed management. The challenges in building such methods lie in dealing with large amounts of discharge noise introduced by the nonlinear nature of hospital procedures, and the nonavailability of real-time clinical information in wards. Objective Our study investigates different models to forecast the total number of next-day discharges from an open ward having no real-time clinical data. Methods We compared 5 popular regression algorithms to model total next-day discharges: (1) autoregressive integrated moving average (ARIMA), (2) the autoregressive moving average with exogenous variables (ARMAX), (3) k-nearest neighbor regression, (4) random forest regression, and (5) support vector regression. Although the autoregressive integrated moving average model relied on past 3-month discharges, nearest neighbor forecasting used median of similar discharges in the past in estimating next-day discharge. In addition, the ARMAX model used the day of the week and number of patients currently in ward as exogenous variables. For the random forest and support vector regression models, we designed a predictor set of 20 patient features and 88 ward-level features. Results Our data consisted of 12,141 patient visits over 1826 days. Forecasting quality was measured using mean forecast error, mean absolute error, symmetric mean absolute percentage error, and root mean square error. When compared with a moving average prediction model, all 5 models demonstrated superior performance with the random forests achieving 22.7% improvement in mean absolute error, for all days in the year 2014. Conclusions In the absence of clinical information, our study recommends using patient-level and ward-level data in predicting next-day discharges. Random forest and support vector regression models are able to use all available features from such data, resulting in superior performance over traditional autoregressive methods. An intelligent estimate of available beds in wards plays a crucial role in relieving access block in emergency departments. PMID:27444059

Development of the silane process for the production of low-cost polysilicon

NASA Technical Reports Server (NTRS)

Iya, S. K.

1986-01-01

It was recognized that the traditional hot rod type deposition process for decomposing silane is energy intensive, and a different approach for converting silane to silicon was chosen. A 1200 metric tons/year capacity commercial plant was constructed in Moses Lake, Washington. A fluidized bed processor was chosen as the most promising technology and several encouraging test runs were conducted. This technology continues to be very promising in producing low cost polysilicon. The Union Carbide silane process and the research development on the fluidized bed silane decomposition are discussed.

Pressurized fluidized bed offers promising route to cogeneration

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

Not Available

1980-03-01

STAL-LAVAL has been monitoring the development of pressurized fluidized-bed combustion (PFBC) technology and has decided to apply it as a way to burn coal and satisfy the important criteria of efficiency, low cost, environmental acceptability, low investment cost, and the capacity to use a wide range of coal qualities. The present status of PFBC and co-generation technology is reviewed and examples of industrial as well as utiltiy applications are cited. A successful commercialization of PFBC could contribute to the success of coal-utilization policies. (DCK)

Evaluation of Sensor Technology to Detect Fall Risk and Prevent Falls in Acute Care.

PubMed

Potter, Patricia; Allen, Kelly; Costantinou, Eileen; Klinkenberg, William Dean; Malen, Jill; Norris, Traci; O'Connor, Elizabeth; Roney, Wilhemina; Tymkew, Heidi Hahn; Wolf, Laurie

2017-08-01

Sensor technology that dynamically identifies hospitalized patients' fall risk and detects and alerts nurses of high-risk patients' early exits out of bed has potential for reducing fall rates and preventing patient harm. During Phase 1 (August 2014-January 2015) of a previously reported performance improvement project, an innovative depth sensor was evaluated on two inpatient medical units to study fall characteristics. In Phase 2 (April 2015-January 2016), a combined depth and bed sensor system designed to assign patient fall probability, detect patient bed exits, and subsequently prevent falls was evaluated. Fall detection depth sensors remained in place on two medicine units; bed sensors used to detect patient bed exits were added on only one of the medicine units. Fall rates and fall with injury rates were evaluated on both units. During Phase 2, the designated evaluation unit had 14 falls, for a fall rate of 2.22 per 1,000 patient-days-a 54.1% reduction compared with the Phase 1 fall rate. The difference in rates from Phase 1 to Phase 2 was statistically significant (z = 2.20; p = 0.0297). The comparison medicine unit had 30 falls-a fall rate of 4.69 per 1,000 patient-days, representing a 57.9% increase as compared with Phase 1. A fall detection sensor system affords a level of surveillance that standard fall alert systems do not have. Fall prevention remains a complex issue, but sensor technology is a viable fall prevention option. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Fixed bed gasification for production of industrial fuel gas

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

Not Available

1977-10-01

This report summarizes the results of technical and economic evaluations of six commercially available, fixed-bed coal gasification processes for the production of industrial fuel gas. The study was performed for DOE and is intended to assist industrial companies in exploring the feasibility of producing gaseous fuels for both retrofit and new industrial plant situations. The report includes a technical analysis of the physical configuration, performance capabilities, and commercial experiments to-date for both air-blown and oxygen-blown fixed bed gasifiers. The product gas from these gasifiers is analyzed economically for three different degrees of cleanliness: (1) hot raw gas, (2) dust-, tar-,more » and oil-free gas, and (3) dust-, tar-, oil-free and desulfurized gas. The evaluations indicate that low-Btu gases produced from fixed bed gasifiers constitute one of the most logical short-term solutions for helping ease the shortage of natural gas for industrial fuel applications because the technology is well-proven and has been utilized on a commercial scale for several decades both in this country and overseas; time from initiation of design to commercial operation is about two years; the technology is not complicated to construct, operate, or maintain; and a reliable supply of product gas can be generated on-site. The advantages and disadvantages of fixed bed gasification technology are listed. The cost of the low Btu gas is estimated at $2 to $4 per MM Btu depending on gas purity, cost of coal ($20 to $50 per ton) and a number of specified assumptions with respect to financing, reliability, etc. (LTN)« less

Development of NASA's Space Communications and Navigation Test Bed Aboard ISS to Investigate SDR, On-Board Networking and Navigation Technologies

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.; Kacpura, Thomas J.; Johnson, Sandra K.; Lux, James P.

2010-01-01

NASA is developing an experimental flight payload (referred to as the Space Communication and Navigation (SCAN) Test Bed) to investigate software defined radio (SDR), networking, and navigation technologies, operationally in the space environment. The payload consists of three software defined radios each compliant to NASA s Space Telecommunications Radio System Architecture, a common software interface description standard for software defined radios. The software defined radios are new technology developments underway by NASA and industry partners. Planned for launch in early 2012, the payload will be externally mounted to the International Space Station truss and conduct experiments representative of future mission capability.

Prospects for using the technology of circulating fluidized bed for technically refitting Russian thermal power stations

NASA Astrophysics Data System (ADS)

Ryabov, G. A.; Folomeev, O. M.; Litun, D. S.; Sankin, D. A.; Dmitryukova, I. G.

2009-01-01

The present state and development of circulating fluidized bed (CFB) technology around the world are briefly reviewed. Questions of increasing the capacity of single boiler units and raising the parameters of steam are discussed. CFB boilers for 225- and 330-MW power units are described and their parameters are estimated as applied to the conditions of firing different Russian fuels. Indicators characterizing CFB boilers and pulverized-coal boilers are given. Capital outlays and operational costs for new coal-fired units are compared, and the results from this comparison are used to show the field of the most promising use of the CFB technology during technical refitting of Russian thermal power stations.

Performance Qualification Test of the ISS Water Processor Assembly (WPA) Expendables

NASA Technical Reports Server (NTRS)

Carter, Layne; Tabb, David; Tatara, James D.; Mason, Richard K.

2005-01-01

The Water Processor Assembly (WPA) for use on the International Space Station (ISS) includes various technologies for the treatment of waste water. These technologies include filtration, ion exchange, adsorption, catalytic oxidation, and iodination. The WPA hardware implementing portions of these technologies, including the Particulate Filter, Multifiltration Bed, Ion Exchange Bed, and Microbial Check Valve, was recently qualified for chemical performance at the Marshall Space Flight Center. Waste water representing the quality of that produced on the ISS was generated by test subjects and processed by the WPA. Water quality analysis and instrumentation data was acquired throughout the test to monitor hardware performance. This paper documents operation of the test and the assessment of the hardware performance.

Test Plan for a Calibration Demonstration System for the Reflected Solar Instrument for the Climate Absolute Radiance and Refractivity Observatory

NASA Technical Reports Server (NTRS)

Thome, Kurtis; McCorkel, Joel; Hair, Jason; McAndrew, Brendan; Daw, Adrian; Jennings, Donald; Rabin, Douglas

2012-01-01

The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe high-accuracy, long-term climate change trends and to use decadal change observations as the most critical method to determine the accuracy of climate change. One of the major objectives of CLARREO is to advance the accuracy of SI traceable absolute calibration at infrared and reflected solar wavelengths. This advance is required to reach the on-orbit absolute accuracy required to allow climate change observations to survive data gaps while remaining sufficiently accurate to observe climate change to within the uncertainty of the limit of natural variability. While these capabilities exist at NIST in the laboratory, there is a need to demonstrate that it can move successfully from NIST to NASA and/or instrument vendor capabilities for future spaceborne instruments. The current work describes the test plan for the Solar, Lunar for Absolute Reflectance Imaging Spectroradiometer (SOLARIS) which is the calibration demonstration system (CDS) for the reflected solar portion of CLARREO. The goal of the CDS is to allow the testing and evaluation of calibration approaches , alternate design and/or implementation approaches and components for the CLARREO mission. SOLARIS also provides a test-bed for detector technologies, non-linearity determination and uncertainties, and application of future technology developments and suggested spacecraft instrument design modifications. The end result of efforts with the SOLARIS CDS will be an SI-traceable error budget for reflectance retrieval using solar irradiance as a reference and methods for laboratory-based, absolute calibration suitable for climate-quality data collections. The CLARREO mission addresses the need to observe high-accuracy, long-term climate change trends and advance the accuracy of SI traceable absolute calibration. The current work describes the test plan for the SOLARIS which is the calibration demonstration system for the reflected solar portion of CLARREO. SOLARIS provides a test-bed for detector technologies, non-linearity determination and uncertainties, and application of future technology developments and suggested spacecraft instrument design modifications. The end result will be an SI-traceable error budget for reflectance retrieval using solar irradiance as a reference and methods for laboratory-based, absolute calibration suitable for climate-quality data collections.

Advanced technologies for Mission Control Centers

NASA Technical Reports Server (NTRS)

Dalton, John T.; Hughes, Peter M.

1991-01-01

Advance technologies for Mission Control Centers are presented in the form of the viewgraphs. The following subject areas are covered: technology needs; current technology efforts at GSFC (human-machine interface development, object oriented software development, expert systems, knowledge-based software engineering environments, and high performance VLSI telemetry systems); and test beds.

Technological and life cycle assessment of organics processing odour control technologies.

PubMed

Bindra, Navin; Dubey, Brajesh; Dutta, Animesh

2015-09-15

As more municipalities and communities across developed world look towards implementing organic waste management programmes or upgrading existing ones, composting facilities are emerging as a popular choice. However, odour from these facilities continues to be one of the most important concerns in terms of cost & effective mitigation. This paper provides a technological and life cycle assessment of some of the different odour control technologies and treatment methods that can be implemented in organics processing facilities. The technological assessment compared biofilters, packed tower wet scrubbers, fine mist wet scrubbers, activated carbon adsorption, thermal oxidization, oxidization chemicals and masking agents. The technologies/treatment methods were evaluated and compared based on a variety of operational, usage and cost parameters. Based on the technological assessment it was found that, biofilters and packed bed wet scrubbers are the most applicable odour control technologies for use in organics processing faculties. A life cycle assessment was then done to compare the environmental impacts of the packed-bed wet scrubber system, organic (wood-chip media) bio-filter and inorganic (synthetic media) bio-filter systems. Twelve impact categories were assessed; cumulative energy demand (CED), climate change, human toxicity, photochemical oxidant formation, metal depletion, fossil depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, terrestrial eco-toxicity, freshwater eco-toxicity and marine eco-toxicity. The results showed that for all impact categories the synthetic media biofilter had the highest environmental impact, followed by the wood chip media bio-filter system. The packed-bed system had the lowest environmental impact for all categories. Copyright © 2015 Elsevier B.V. All rights reserved.

The Space Station Module Power Management and Distribution automation test bed

NASA Technical Reports Server (NTRS)

Lollar, Louis F.

1991-01-01

The Space Station Module Power Management And Distribution (SSM/PMAD) automation test bed project was begun at NASA/Marshall Space Flight Center (MSFC) in the mid-1980s to develop an autonomous, user-supportive power management and distribution test bed simulating the Space Station Freedom Hab/Lab modules. As the test bed has matured, many new technologies and projects have been added. The author focuses on three primary areas. The first area is the overall accomplishments of the test bed itself. These include a much-improved user interface, a more efficient expert system scheduler, improved communication among the three expert systems, and initial work on adding intermediate levels of autonomy. The second area is the addition of a more realistic power source to the SSM/PMAD test bed; this project is called the Large Autonomous Spacecraft Electrical Power System (LASEPS). The third area is the completion of a virtual link between the SSM/PMAD test bed at MSFC and the Autonomous Power Expert at Lewis Research Center.

Three-dimensional flow structure and patterns of bed shear stress in an evolving compound meander bend

USGS Publications Warehouse

Engel, Frank; Rhoads, Bruce L.

2016-01-01

Compound meander bends with multiple lobes of maximum curvature are common in actively evolving lowland rivers. Interaction among spatial patterns of mean flow, turbulence, bed morphology, bank failures and channel migration in compound bends is poorly understood. In this paper, acoustic Doppler current profiler (ADCP) measurements of the three-dimensional (3D) flow velocities in a compound bend are examined to evaluate the influence of channel curvature and hydrologic variability on the structure of flow within the bend. Flow structure at various flow stages is related to changes in bed morphology over the study timeframe. Increases in local curvature within the upstream lobe of the bend reduce outer bank velocities at morphologically significant flows, creating a region that protects the bank from high momentum flow and high bed shear stresses. The dimensionless radius of curvature in the upstream lobe is one-third less than that of the downstream lobe, with average bank erosion rates less than half of the erosion rates for the downstream lobe. Higher bank erosion rates within the downstream lobe correspond to the shift in a core of high velocity and bed shear stresses toward the outer bank as flow moves through the two lobes. These erosion patterns provide a mechanism for continued migration of the downstream lobe in the near future. Bed material size distributions within the bend correspond to spatial patterns of bed shear stress magnitudes, indicating that bed material sorting within the bend is governed by bed shear stress. Results suggest that patterns of flow, sediment entrainment, and planform evolution in compound meander bends are more complex than in simple meander bends. Moreover, interactions among local influences on the flow, such as woody debris, local topographic steering, and locally high curvature, tend to cause compound bends to evolve toward increasing planform complexity over time rather than stable configurations.

Novel CFB Boiler Technology with Reconstruction of its Fluidization State

NASA Astrophysics Data System (ADS)

Yang, H. R.; Zhang, H.; Lu, J. F.; Lfu, Q.; Wu, Y. X.; Yuet, G. X.; Su, J.; Fu, Z. P.

Compared with a conventional pulverized coal fired boiler, the combustion efficiency of a CFB boiler is lower while the self-consumed service power is 1-2% higher. The solution of these problems is the key research topic for researchers and manufacturers of CFB boilers. Based on the State Specification Design Theory of CFB boilers, Tsinghua University proposed a novel CFB technology by reconstruction of the fluidization state in the furnace by adjusting the bed inventory and bed quality. Theoretical analyses show that there is an optimal bed pressure drop, around which the boiler operation can achieve the maximal combustion efficiency and with significant reduction of the wear of the heating surface and fan power consumption. The proposed novel process was implemented in a 75t/h CFB boiler. The results of field tests on this boiler validated the theoretical analyses.

Biochemical separations by continuous-bed chromatography.

PubMed

Tisch, T L; Frost, R; Liao, J L; Lam, W K; Remy, A; Scheinpflug, E; Siebert, C; Song, H; Stapleton, A

1998-08-07

Innovations in column-packing media for biomolecule purification have progressed from large spherical, porous polysaccharide beads to advanced polymeric supports. Continuous-bed technology is a radical new technology for chromatography based on the polymerization of advanced monomers and ionomers directly in the chromatographic column. The polymer chains form aggregates which coalesce into a dense, homogeneous network of interconnected nodules consisting of microparticles with an average diameter of 3000 A. The voids or channels between the nodules are large enough to permit a high hydrodynamic flow. Due to the high cross-linking of the polymer matrix, the surface of each nodule is nonporous yet the polymeric microparticles provide a very large surface area for high binding capacity. This paper will demonstrate the properties and advantages of using a continuous bed support for high resolution biomolecule separations at high flow-rates without sacrificing capacity.

Rapid Access Ice Drill: A New Tool for Exploration of the Deep Antarctic Ice Sheets and Subglacial Geology

NASA Astrophysics Data System (ADS)

Goodge, J. W.; Severinghaus, J. P.

2014-12-01

The Rapid Access Ice Drill (RAID) will penetrate the Antarctic ice sheets in order to core through deep ice, the glacial bed, and into bedrock below. This new technology will provide a critical first look at the interface between major ice caps and their subglacial geology. Currently in construction, RAID is a mobile drilling system capable of making several long boreholes in a single field season in Antarctica. RAID is interdisciplinary and will allow access to polar paleoclimate records in ice >1 Ma, direct observation at the base of the ice sheets, and recovery of rock cores from the ice-covered East Antarctic craton. RAID uses a diamond rock-coring system as in mineral exploration. Threaded drill-pipe with hardened metal bits will cut through ice using reverse circulation of Estisol for pressure-compensation, maintenance of temperature, and removal of ice cuttings. Near the bottom of the ice sheet, a wireline bottom-hole assembly will enable diamond coring of ice, the glacial bed, and bedrock below. Once complete, boreholes will be kept open with fluid, capped, and made available for future down-hole measurement of thermal gradient, heat flow, ice chronology, and ice deformation. RAID will also sample for extremophile microorganisms. RAID is designed to penetrate up to 3,300 meters of ice and take sample cores in less than 200 hours. This rapid performance will allow completion of a borehole in about 10 days before moving to the next drilling site. RAID is unique because it can provide fast borehole access through thick ice; take short ice cores for paleoclimate study; sample the glacial bed to determine ice-flow conditions; take cores of subglacial bedrock for age dating and crustal history; and create boreholes for use as an observatory in the ice sheets. Together, the rapid drilling capability and mobility of the drilling system, along with ice-penetrating imaging methods, will provide a unique 3D picture of the interior Antarctic ice sheets.

Hybrid moving bed biofilm reactors: a pilot plant experiment.

PubMed

Di Trapani, D; Mannina, G; Torregrossa, M; Viviani, G

2008-01-01

The growing increment of the urbanization and, on the other hand, the even more strict effluent limits imposed by the Water Framework Directive for the receiving water body quality state have led to the need for upgrading several existing WWTP. With this respect HMBBR systems are an innovative solution since they allow to upgrade existing high loaded WWTP without building new tanks. However, some uncertainties in their design, maintenance as well as performance have to be addressed due to their recent acquisition compared with well consolidated technologies such as activated sludge systems. In this light, a data gathering campaign on a HMBBR pilot plant has been performed. The aim was to detect the performance of such new technology as well as to survey the influencing effect of the carrier media filling ratio. Indeed, there may be problem of competitiveness between attached and suspended biomass that jointly operate in the same system for carbon and nitrogen removal. Such competitiveness may lead to a worsening of the system efficiency. The results are interesting and the gathered data in the experimental period show a slight difference in terms of performance behaviour, between the two systems (35 and 66%). Such result leads to address the filling ratio choice towards the 35%. IWA Publishing 2008.

Integrated detoxification methodology of hazardous phenolic wastewaters in environmentally based trickle-bed reactors: Experimental investigation and CFD simulation.

PubMed

Lopes, Rodrigo J G; Almeida, Teresa S A; Quinta-Ferreira, Rosa M

2011-05-15

Centralized environmental regulations require the use of efficient detoxification technologies for the secure disposal of hazardous wastewaters. Guided by federal directives, existing plants need reengineering activities and careful analysis to improve their overall effectiveness and to become environmentally friendly. Here, we illustrate the application of an integrated methodology which encompasses the experimental investigation of catalytic wet air oxidation and CFD simulation of trickle-bed reactors. As long as trickle-bed reactors are determined by the flow environment coupled with chemical kinetics, first, on the optimization of prominent numerical solution parameters, the CFD model was validated with experimental data taken from a trickle bed pilot plant specifically designed for the catalytic wet oxidation of phenolic wastewaters. Second, several experimental and computational runs were carried out under unsteady-state operation to evaluate the dynamic performance addressing the TOC concentration and temperature profiles. CFD computations of total organic carbon conversion were found to agree better with experimental data at lower temperatures. Finally, the comparison of test data with simulation results demonstrated that this integrated framework was able to describe the mineralization of organic matter in trickle beds and the validated consequence model can be exploited to promote cleaner remediation technologies of contaminated waters. Copyright © 2011 Elsevier B.V. All rights reserved.

Fluidized-Bed Heat Transfer Modeling for the Development of Particle/Supercritical-CO2 Heat Exchanger

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

Ma, Zhiwen; Martinek, Janna G

Concentrating solar power (CSP) technology is moving toward high-temperature and high-performance design. One technology approach is to explore high-temperature heat-transfer fluids and storage, integrated with a high-efficiency power cycle such as the supercritical carbon dioxide (s-CO2) Brayton power cycle. The s-CO2 Brayton power system has great potential to enable the future CSP system to achieve high solar-to-electricity conversion efficiency and to reduce the cost of power generation. Solid particles have been proposed as a possible high-temperature heat-transfer medium that is inexpensive and stable at high temperatures above 1,000 degrees C. The particle/heat exchanger provides a connection between the particles andmore » s-CO2 fluid in the emerging s-CO2 power cycles in order to meet CSP power-cycle performance targets of 50% thermal-to-electric efficiency, and dry cooling at an ambient temperature of 40 degrees C. The development goals for a particle/s-CO2 heat exchanger are to heat s-CO2 to =720 degrees C and to use direct thermal storage with low-cost, stable solid particles. This paper presents heat-transfer modeling to inform the particle/s-CO2 heat-exchanger design and assess design tradeoffs. The heat-transfer process was modeled based on a particle/s-CO2 counterflow configuration. Empirical heat-transfer correlations for the fluidized bed and s-CO2 were used in calculating the heat-transfer area and optimizing the tube layout. A 2-D computational fluid-dynamics simulation was applied for particle distribution and fluidization characterization. The operating conditions were studied from the heat-transfer analysis, and cost was estimated from the sizing of the heat exchanger. The paper shows the path in achieving the cost and performance objectives for a heat-exchanger design.« less

Bed Bugs: Clinical Relevance and Control Options

PubMed Central

Dwyer, Dominic E.; Peñas, Pablo F.; Russell, Richard C.

2012-01-01

Summary: Since the late 1990s, bed bugs of the species Cimex lectularius and Cimex hemipterus have undergone a worldwide resurgence. These bed bugs are blood-sucking insects that readily bite humans. Cutaneous reactions may occur and can start out as small macular lesions that can develop into distinctive wheals of around 5 cm in diameter, which are accompanied by intense itching. Occasionally, bullous eruptions may result. If bed bugs are numerous, the patient can present with widespread urticaria or eythematous rashes. Often, bites occur in lines along the limbs. Over 40 pathogens have been detected in bed bugs, but there is no definitive evidence that they transmit any disease-causing organisms to humans. Anemia may result when bed bugs are numerous, and their allergens can trigger asthmatic reactions. The misuse of chemicals and other technologies for controlling bed bugs has the potential to have a deleterious impact on human health, while the insect itself can be the cause of significant psychological trauma. The control of bed bugs is challenging and should encompass a multidisciplinary approach utilizing nonchemical means of control and the judicious use of insecticides. For accommodation providers, risk management procedures should be implemented to reduce the potential of bed bug infestations. PMID:22232375

Design assessment of a 150 kWt CFBC Test Unit

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

Batu, A.; Selcuk, N.; Kulah, G.

2010-04-15

For clean and efficient energy generation from coal, the most suitable technology known to date is 'Fluidized Bed Combustion' technology. Applications of circulating fluidized bed (CFB) combustion technology have been steadily increasing in both capacity and number over the past decade. Designs of these units have been based on the combustion tests carried out in pilot scale facilities to determine the combustion and desulfurization characteristics of coal and limestone reserves in CFB conditions. Similarly, utilization of Turkish lignites in CFB boilers necessitates adaptation of CFB combustion technology to these resources. However, the design of these test units are not basedmore » on firing coals with high ash, volatile matter and sulfur contents like Turkish lignites. For this purpose, a 150 kWt CFB combustor test unit is designed and constructed in Chemical Engineering Department of Middle East Technical University, based on the extensive experience acquired at the existing 0.3 MWt Bubbling Atmospheric Fluidized Bed Combustor (AFBC) Test Rig. Following the commissioning tests, a combustion test is carried out for investigation of combustion characteristics of Can lignite in CFB conditions and for assessment of the design of test unit. Comparison of the design outputs with experimental results reveals that most of the predictions and assumptions have acceptable agreement with the operating conditions. In conclusion, the performance of 150 kWt CFBC Test Unit is found to be satisfactory to be utilized for the long term research studies on combustion and desulfurization characteristics of indigenous lignite reserves in circulating fluidized bed combustors. (author)« less

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

Mutanen, K.I.

Development of fluidized bed combustion (FBC) was started both in North America and in Europe in the 1960`s. In Europe and especially in Scandinavia the major driving force behind the development was the need to find new more efficient technologies for utilization of low-grade fuels like different biomasses and wastes. Both bubbling fluidized bed (BFB) and circulating fluidized bed (CFB) technologies were under intensive R&D,D efforts and have now advanced to dominating role in industrial and district heating power plant markets in Europe. New advanced CFB designs are now entering the markets. In North America and especially in the USmore » the driving force behind the FBC development was initially the need to utilize different types of coals in a more efficient and environmentally acceptable way. The present and future markets seem to be mainly in biomass and multifuel applications where there is benefit from high combustion efficiency, high fuel flexibility and low emissions such as in the pulp and paper industry. The choice between CFB technology and BFB technology is based on selected fuels, emission requirements, plant size and on technical and economic feasibility. Based on Scandinavian experience there is vast potential in the North American industry to retrofit existing oil fired, pulverized coal fired, chemical recovery or grate fired boilers with FBC systems or to build a new FBC based boiler plant. This paper will present the status of CFB technologies and will compare technical and economic feasibility of CFB technology to CFB technology to BFB and also to other combustion methods. Power plant projects that are using advanced CFB technology e.g. Ahlstrom Pyroflow Compact technology for biomass firing and co-firing of biomass with other fuels will also be introduced.« less

Moving Bed Granular Bed Filter Development Program. Topical report, September 1994

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

Haas, J.C.; Prudhomme, J.W.; Wilson, K.W.

1994-09-01

Five test arrangements have been designed to support the Granular Bed Filter Development Program as defined in the Test Plan. The first arrangement is a 3.6 ft. diameter half filter, with a glass covering along the cross section to allow visual examination of the granular alumina material passing through the filter. The second test arrangement is a 3.6 ft diameter full size filter having refractory lining to simulate actual surface roughness conditions. The third test arrangement will examine filter geometry scale up by testing a 6.0 ft. diameter full size filter. The fourth Test Arrangement consists of a small 12more » inch diameter fluidizer to measure the minimum fluidization velocity of the 7 m (approx. size) alumina material to be used in the filter assemblies. The last Test Unit is used to evaluation relative abrasion characteristics of potential refractory and ceramic materials to be installed in high abrasion areas in the pneumatic transport piping.« less

CFD modelling of liquid-solid transport in the horizontal eccentric annuli

NASA Astrophysics Data System (ADS)

Sayindla, Sneha; Challabotla, Niranjan Reddy

2017-11-01

In oil and gas drilling operations, different types of drilling fluids are used to transport the solid cuttings in an annulus between drill pipe and well casing. The inner pipe is often eccentric and flow inside the annulus can be laminar or turbulent regime. In the present work, Eulerian-Eulerian granular multiphase CFD model is developed to systematically investigate the effect of the rheology of the drilling fluid type (Newtonian and non-Newtonian), drill pipe eccentricity and inner pipe rotation on the efficiency of cuttings transport. Both laminar and turbulent flow regimes were considered. Frictional pressure drop is computed and compared with the flow loop experimental results reported in the literature. The results confirm that the annular frictional pressure loss in a fully eccentric annulus are significantly lesser than the concentric annulus. Inner pipe rotation improve the efficiency of the cuttings transport in laminar flow regime. Cuttings transport velocity and concentration distribution were analysed to predict the different flow patterns such as stationary bed, moving bed, heterogeneous and homogeneous bed formation.

Process for gasifying carbonaceous material from a recycled condensate slurry

DOEpatents

Forney, Albert J.; Haynes, William P.

1981-01-01

Coal or other carbonaceous material is gasified by reaction with steam and oxygen in a manner to minimize the problems of effluent water stream disposal. The condensate water from the product gas is recycled to slurry the coal feed and the amount of additional water or steam added for cooling or heating is minimized and preferably kept to a level of about that required to react with the carbonaceous material in the gasification reaction. The gasification is performed in a pressurized fluidized bed with the coal fed in a water slurry and preheated or vaporized by indirect heat exchange contact with product gas and recycled steam. The carbonaceous material is conveyed in a gas-solid mixture from bottom to top of the pressurized fluidized bed gasifier with the solids removed from the product gas and recycled steam in a supported moving bed filter of the resulting carbonaceous char. Steam is condensed from the product gas and the condensate recycled to form a slurry with the feed coal carbonaceous particles.

Fixed Bed Column Study for Adsolubilization of 2,4-D Herbicide on Surfactant Modified Silica Gel Waste

NASA Astrophysics Data System (ADS)

Koner, S.; Adak, A.

2012-09-01

The fixed bed column study was conducted for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D), a widely used herbicide from synthetically prepared wastewater using surfactant modified silica gel waste (SMSGW) as an adsorbing media. The adsorbing media was prepared by treating silica gel waste (SGW) with cationic surfactant. The removal was due to adsolubilization of 2,4-D molecules within the admicelles formed on the surface of SGW. The column having 2.5 cm diameter, with different bed heights such as 20, 30 and 40 cm were used in the study. The different column design parameters like depth of exchange zone, time required for exchange zone to move its own height, adsorption rate constant, adsorption capacity constant were calculated using BDST model. The SMSGW was found to be a very efficient media for the removal of 2,4-D from wastewater. Column design parameters were modeled for different field conditions to predict the duration of column run for practical application.

Nondestructive Quantitative Sampling for Freshwater Mussels in Variable Substrate Streams

Treesearch

John B. Richardson; Winston Paul Smith

1994-01-01

Unionidmussels were sampled in the Big South Fork of the Cumberland River, Tennessee and Kentucky, from July to October 1988 with a chain grid of10 l-m2 quadrats. The chain grid was used to define 100-m2 areas along the stream bed by repeatedly moving the10-m2 rectangle upstream. Within each100-m

Illustrative Experiments of the Erosion of Sand and Accompanying Theoretical Considerations

ERIC Educational Resources Information Center

Schneiderbauer, Simon

2012-01-01

Winds in desert regions form the well-known barchan dunes. Frequently, human settlements are threatened by the migration of these dunes. But why do these dunes move? And how is dune migration in deserts connected to scour development in the vicinity of pylons in river beds or to snow cornices in alpine regions? This paper introduces the topic of…

Laying hen performance and well-being over two flock cycles on different litter substrates in an aviary housing

USDA-ARS?s Scientific Manuscript database

The momentum to move toward aviary housing has continued to increase in the past eight months. The pressure to find consistent bedding sources for meat birds may impact litter substrate for the laying hen industry as the number of cage-free hens increases in the next nine years. Molting laying hens ...

Intermittent simulated moving bed chromatography: 3. Separation of Tröger's base enantiomers under nonlinear conditions.

PubMed

Katsuo, Shigeharu; Langel, Christian; Sandré, Anne-Laure; Mazzotti, Marco

2011-12-30

One of the modified simulated moving bed (SMB) processes, the intermittent SMB (I-SMB) process, has been recently analyzed theoretically [1] and its superior performance compared to the conventional SMB process has been demonstrated at a rather low total feed concentration through experiments and simulations [2]. This work shows that the I-SMB process outperforms the conventional SMB process also at high feed concentration where the species are clearly subject to a nonlinear adsorption isotherm. In the case of the separation of the Tröger's base's enantiomers in ethanol on ChiralPak AD, the two processes operated in a six-column 1-2-2-1 configuration (one column in sections 1 and 4 and two columns in sections 2 and 3) and in a four-column 1-1-1-1 configuration (one column in each section) are compared at high feed concentration through both experiments and simulations. Even under nonlinear conditions the four column I-SMB process can successfully separate the two enantiomers achieving purity levels as high as the two six column processes and exhibiting better productivity. Copyright © 2011 Elsevier B.V. All rights reserved.

Microbial community composition of a multi-stage moving bed biofilm reactor and its interaction with kinetic model parameters estimation.

PubMed

Wang, Xiaodong; Bi, Xuejun; Hem, Lars John; Ratnaweera, Harsha

2018-07-15

Microbial community diversity determines the function of each chamber of multi-stage moving bed biofilm reactor (MBBR) systems. How the microbial community data can be further used to serve wastewater treatment process modelling and optimization has been rarely studied. In this study, a MBBR system was set up to investigate the microbial community diversity of biofilm in each functional chamber. The compositions of microbial community of biofilm from different chambers of MBBR were quantified by high-throughput sequencing. Significantly higher proportion of autotrophs were found in the second aerobic chamber (15.4%), while 4.3% autotrophs were found in the first aerobic chamber. Autotrophs in anoxic chamber were negligible. Moreover, ratios of active heterotrophic biomass and autotrophic biomass (X H /X A ) were obtained by performing respiration tests. By setting heterotroph/autotroph ratios obtained from sequencing analysis equal to X H /X A , a novel approach for kinetic model parameters estimation was developed. This work not only investigated microbial community of MBBR system, but also it provided an approach to make further use of molecular microbiology analysis results. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluating a strategy for maintaining nitrifier activity during long-term starvation in a moving bed biofilm reactor (MBBR) treating reverse osmosis concentrate.

PubMed

Ye, Liu; Hu, Shihu; Poussade, Yvan; Keller, Jurg; Yuan, Zhiguo

2012-01-01

A two-stage moving bed biofilm reactor (MBBR) was applied at the Bundamba advanced water treatment plant (AWTP) (Queensland, Australia) to treat the reverse osmosis concentrate (ROC) for inorganic nutrient removal. One of the operational challenges for the system was to cope with the large fluctuations of the ROC flow. This study investigated the decay rates of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) and biofilm detachment in MBBR during starvation for up to one month. An intermittent aeration strategy of 15 min aeration every 6 h was applied. This study also evaluated the activity recovery of both AOB and NOB after normal operation was resumed. The results showed that the activity loss of AOB and NOB was relatively minor (<20%) within 10 days of starvation, which ensured relatively quick recovery of ammonium removal when normal operation resumed. In contrast, the AOB and NOB activity loss reached 60-80% when the starvation time was longer than 20 days, resulting in slower recovery of ammonium removal after starvation. Starvation for less than 20 days didn't result in an apparent biomass detachment from carriers.

Highly-resolved numerical simulations of bed-load transport in a turbulent open-channel flow

NASA Astrophysics Data System (ADS)

Vowinckel, Bernhard; Kempe, Tobias; Nikora, Vladimir; Jain, Ramandeep; Fröhlich, Jochen

2015-11-01

The study presents the analysis of phase-resolving Direct Numerical Simulations of a horizontal turbulent open-channel flow laden with a large number of spherical particles. These particles have a mobility close to their threshold of incipient motion andare transported in bed-load mode. The coupling of the fluid phase with the particlesis realized by an Immersed Boundary Method. The Double-Averaging Methodology is applied for the first time convolutingthe data into a handy set of quantities averaged in time and space to describe the most prominent flow features.In addition, a systematic study elucidatesthe impact of mobility and sediment supply on the pattern formation of particle clusters ina very large computational domain. A detailed description of fluid quantities links the developed particle patterns to the enhancement of turbulence and to a modified hydraulic resistance. Conditional averaging isapplied toerosion events providingthe processes involved inincipient particle motion. Furthermore, the detection of moving particle clusters as well as their surrounding flow field is addressedby a a moving frameanalysis. Funded by German Research Foundation (DFG), project FR 1593/5-2, computational time provided by ZIH Dresden, Germany, and JSC Juelich, Germany.

Degradation of mecoprop in polluted landfill leachate and waste water in a moving bed biofilm reactor.

PubMed

Escolà Casas, Mònica; Nielsen, Tue Kjærgaard; Kot, Witold; Hansen, Lars Hestbjerg; Johansen, Anders; Bester, Kai

2017-09-15

Mecoprop is a common pollutant in effluent-, storm- and groundwater as well as in leachates from derelict dumpsites. Thus, bioremediation approaches may be considered. We conducted batch experiments with moving bed biofilm (MBBR)-carriers to understand the degradation of mecoprop. As a model, the carriers were incubated in effluent from a conventional wastewater treatment plant which was spiked to 10, 50 and 100 μg L -1 mecoprop. Co-metabolic processes as well as mineralization were studied. Initial mecoprop concentration and mecoprop degradation impacted the microbial communities. The removal of (S)-mecoprop prevailed over the (R)-mecoprop. This was associated with microbial compositions, in which several operational taxonomic units (OTUs) co-varied positively with (S)-mecoprop removal. The removal-rate constant of (S)-mecoprop was 0.5 d -1 in the 10 μg L -1 set-up but it decreased in the 50 and 100 μg L -1 set-ups. The addition of methanol prolonged the removal of (R)-mecoprop. During mecoprop degradation, 4-chloro-2-methylphenol was formed and degraded. A new metabolite (4-chloro-2-methylphenol sulfate) was identified and quantified. Copyright © 2017 Elsevier Ltd. All rights reserved.

Responses of biofilm characteristics to variations in temperature and NH4(+)-N loading in a moving-bed biofilm reactor treating micro-polluted raw water.

PubMed

Zhang, Shuangfu; Wang, Yayi; He, Weitao; Wu, Min; Xing, Meiyan; Yang, Jian; Gao, Naiyun; Yin, Daqiang

2013-03-01

A pilot-scale moving-bed biofilm reactor (MBBR) for biological treatment of micro-polluted raw water was operated over 400days to investigate the responses of biofilm characteristics and nitrification performance to variations in temperature and NH4(+)-N loading. The mean removal efficiency of NH4(+)-N in the MBBR reached 71.4±26.9%, and batch experiments were performed to study nitrification kinetics for better process understanding. Seven physical-chemical parameters, including volatile solids (VS), polysaccharides (PS) and phospholipids (PL) increased firstly, and then rapidly decreased with increasing temperature and NH4(+)-N loading, and properly characterized the attached biomass during biofilm development and detachment in the MBBR. The biofilm compositions were described by six ratios, e.g., PS/VS and PL/VS ratios showed different variation trends, indicating different responses of PS and PL to the changes in temperature and NH4(+)-N loading. Furthermore, fluorescent in situ hybridization (FISH) analysis revealed that increased NH4(+)-N loadings caused an enrichment of the nitrifying biofilm. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Factors for Degaussing of a Cochlear Implant Magnet in the MR Scanner].

PubMed

Koganezawa, Takumi; Uchiyama, Naoko; Teshigawara, Mai; Ogura, Akio

This study examined the conditions influencing degauss of the magnet using magnetic resonance imaging (MRI). Poly methyl methacrylate (PMMA) was used to fix the measurement magnets to the MRI bed at angles from 0° to 180° for the magnetic flux vector of static magnetic field. The PMMA was moved in the MRI magnetic field. Magnetic flux density was measured before and after bed movement, and the rate of degauss was calculated. The contents examined are as follows: (1) the angle of the magnetic flux vector of the measurement magnets for the magnetic flux vector of the static magnetic field, (2) the number of movements, (3) moving velocity, and (4) the movement on the spatial gradient of magnetic field. Mann-Whitney U test was used for statistical analysis of the data. In conclusion, the effect of the angle of the magnetic flux vector of the implant magnet was high under the conditions of degauss in this study. Therefore, during the MRI examination of a patient with a cochlear implant magnet, the operators identified the directions of the magnetic flux vector and static magnetic field of the implant magnet.

Impact of fine mesh sieve primary treatment on nitrogen removal in moving bed biofilm reactors.

PubMed

Rusten, B; Razafimanantsoa, V A; Andriamiarinjaka, M A; Otis, C L; Sahu, A K; Bilstad, T

2016-01-01

The purpose of this project was to investigate the effect of selective particle removal during primary treatment on nitrogen removal in moving bed biofilm reactors (MBBRs). Two small MBBR pilot plants were operated in parallel, where one train treated 2 mm screened municipal wastewater and the other train treated wastewater that had passed through a Salsnes Filter SF1000 rotating belt sieve (RBS) with a 33 µs sieve cloth. The SF1000 was operated without a filter mat on the belt. The tests confirmed that, for the wastewater characteristics at the test plant, Salsnes Filter primary treatment with a 33 µs RBS and no filter mat produced a primary effluent that was close to optimum. Removal of organic matter with the 33 µs sieve had no negative effect on the denitrification process. Nitrification rates improved by 10-15% in the train with 33 µs RBS primary treatment. Mass balance calculations showed that without RBS primary treatment, the oxygen demand in the biological system was 36% higher. Other studies have shown that the sludge produced by RBS primary treatment is beneficial for biogas production and will also significantly improve sludge dewatering of the combined primary and biological sludge.

Glacitectonic deformation around the retreating margin of the last Irish ice sheet

NASA Astrophysics Data System (ADS)

Knight, J.

2008-12-01

Evidence for ice-marginal glacitectonic shunting and deformation of bedrock slabs is described from three sites around the west coast of Ireland. These sites (Brandon Bay, County Kerry; Pigeon Point, County Mayo; Inishcrone, County Sligo) are all locations where the late Devensian ice margin retreated on land and was confined to within limestone bedrock embayments. At these sites, flat-lying bedrock slabs (< 8 m long) have been dissociated from rockhead and moved seaward (in the direction of ice flow) by glacitectonic shunting. At all of the sites, bedrock slabs have been variously stacked, rotated, deformed into open folds, and brecciated. Separating the bedrock slabs is either a thin layer (< 20 cm) of brecciated and mylonitised cemented bedrock that shows internal folding; or a thicker (< 50 cm) normally-graded diamicton with a fine matrix. Together, the presence of these features suggests oscillation of a polythermal and clean basal ice margin that was strongly associated with basal freeze-on and the presence of proglacial permafrost. Subglacial sediment-laden meltwater was focused from behind the ice margin and through permafrost taliks. It is suggested that hydrofracturing under high hydraulic pressure, and through a frozen-bed ice margin, forced sediment injection into bedrock fractures and bedding planes and away from the ice margin, and that bedrock slabs were moved in part by hydraulic lift as well as thrust-style ice-marginal tectonics. The presence of a mosaic of warm and frozen ice-bed patches, in combination with strong geologic control and meltwater generation from behind the ice margin, can help explain formation of these unusual bedrock slab features.

Optical coherence tomography for non-destructive analysis of coatings in pharmaceutical tablets

NASA Astrophysics Data System (ADS)

Markl, Daniel; Hannesschläger, Günther; Sacher, Stephan; Khinast, Johannes G.; Leitner, Michael

2013-04-01

Tablet coating is a common pharmaceutical technique to apply a thin continuous layer of solid on the top of a tablet or a granule containing active pharmaceutical ingredients (APIs). Coating thickness and homogeneity are critical parameters regarding the drug release rate, and consequently a direct or indirect monitoring strategy of these critical process parameters is essential. With the aid of Optical Coherence Tomography (OCT) it is not only possible to measure the absolute coating thickness, but also to detect inhomogeneities in the coating or substrate material. In this work the possible application of OCT as in-line method for monitoring pharmaceutical tablet film coating is studied. Firstly, the feasibility of OCT for analysis tablet coating is examined. Seven different commercially available film-coated tablets with different shapes, formulations and coating thicknesses were investigated off-line. OCT images were acquired by two different spectral-domain OCT systems operating at center wavelengths of 830 and 1325 nm. Since the images of both systems allow the analysis of the coatings, the OCT system employing the shorter wavelength and thus providing a higher axial resolution was selected for the further experiments. The influence of a moving tablet bed on OCT images was analyzed by considering a static tablet bed and moving the sensor head along the tablet bed. The ability to analyze the coating homogeneity is limited to a speed up to 0.3 m/s. However, determining the coating thickness and inter-coating uniformity is still possible up to a speed of 0.7 m/s.

Formulating food protein-stabilized indomethacin nanosuspensions into pellets by fluid-bed coating technology: physical characterization, redispersibility, and dissolution.

PubMed

He, Wei; Lu, Yi; Qi, Jianping; Chen, Lingyun; Yin, Lifang; Wu, Wei

2013-01-01

Drug nanosuspensions are very promising for enhancing the dissolution and bioavailability of drugs that are poorly soluble in water. However, the poor stability of nanosuspensions, reflected in particle growth, aggregation/agglomeration, and change in crystallinity state greatly limits their applications. Solidification of nanosuspensions is an ideal strategy for addressing this problem. Hence, the present work aimed to convert drug nanosuspensions into pellets using fluid-bed coating technology. Indomethacin nanosuspensions were prepared by the precipitation-ultrasonication method using food proteins (soybean protein isolate, whey protein isolate, β-lactoglobulin) as stabilizers. Dried nanosuspensions were prepared by coating the nanosuspensions onto pellets. The redispersibility, drug dissolution, solid-state forms, and morphology of the dried nanosuspensions were evaluated. The mean particle size for the nanosuspensions stabilized using soybean protein isolate, whey protein isolate, and β-lactoglobulin was 588 nm, 320 nm, and 243 nm, respectively. The nanosuspensions could be successfully layered onto pellets with high coating efficiency. Both the dried nanosuspensions and nanosuspensions in their original amorphous state and not influenced by the fluid-bed coating drying process could be redispersed in water, maintaining their original particle size and size distribution. Both the dried nanosuspensions and the original drug nanosuspensions showed similar dissolution profiles, which were both much faster than that of the raw crystals. Fluid-bed coating technology has potential for use in the solidification of drug nanosuspensions.

Mitigation of High Altitude and Low Earth Orbit Radiation Effects on Microelectronics via Shielding or Error Detection and Correction Systems

NASA Technical Reports Server (NTRS)

Gupta, Kajal (Technical Monitor); Kirby, Kelvin

2004-01-01

The NASA Cooperative Agreement NAG4-210 was granted under the FY2000 Faculty Awards for Research (FAR) Program. The project was proposed to examine the effects of charged particles and neutrons on selected random access memory (RAM) technologies. The concept of the project was to add to the current knowledge of Single Event Effects (SEE) concerning RAM and explore the impact of selected forms of radiation on Error Detection and Correction Systems. The project was established as an extension of a previous FAR awarded to Prairie View A&M University (PVAMU), under the direction of Dr. Richard Wilkins as principal investigator. The NASA sponsored Center for Applied Radiation Research (CARR) at PVAMU developed an electronic test-bed to explore and quantify SEE on RAM from charged particles and neutrons. The test-bed was developed using 486DX microprocessor technology (PC-104) and a custom test board to mount RAM integrated circuits or other electronic devices. The test-bed had two configurations - a bench test version for laboratory experiments and a 400 Hz powered rack version for flight experiments. The objectives of this project were to: 1) Upgrade the Electronic Test-bed (ETB) to a Pentium configuration; 2) Accommodate more than only 8 Mbytes of RAM; 3) Explore Error Detection and Correction Systems for radiation effects; 4) Test modern RAM technologies in radiation environments.

Tetherless ergonomics workstation to assess nurses' physical workload in a clinical setting.

PubMed

Smith, Warren D; Nave, Michael E; Hreljac, Alan P

2011-01-01

Nurses are at risk of physical injury when moving immobile patients. This paper describes the development and testing of a tetherless ergonomics workstation that is suitable for studying nurses' physical workload in a clinical setting. The workstation uses wearable sensors to record multiple channels of body orientation and muscle activity and wirelessly transmits them to a base station laptop computer for display, storage, and analysis. In preparation for use in a clinical setting, the workstation was tested in a laboratory equipped for multi-camera video motion analysis. The testing included a pilot study of the effect of bed height on student nurses' physical workload while they repositioned a volunteer posing as a bedridden patient toward the head of the bed. Each nurse subject chose a preferred bed height, and data were recorded, in randomized order, with the bed at this height, at 0.1 m below this height, and at 0.1 m above this height. The testing showed that the body orientation recordings made by the wearable sensors agreed closely with those obtained from the video motion analysis system. The pilot study showed the following trends: As the bed height was raised, the nurses' trunk flexion at both thoracic and lumbar sites and lumbar muscle effort decreased, whereas trapezius and deltoid muscle effort increased. These trends will be evaluated by further studies of practicing nurses in the clinical setting.

Buffer management to solve bed-blocking in the Netherlands 2000–2010. Cooperation from an integrated care chain perspective as a key success factor for managing patient flows

PubMed Central

Mur-Veeman, Ingrid; Govers, Mark

2011-01-01

Introduction Bed-blocking problems in hospitals reflect how difficult and complex it is to move patients smoothly through the chain of care. In the Netherlands, during the first decade of the 21st century, some hospitals attempted to tackle this problem by using an Intermediate Care Department (ICD) as a buffer for bed-blockers. However, research has shown that ICDs do not sufficiently solve the bed-blocking problem and that bed-blocking is often caused by a lack of buffer management. Tool Buffer management (BM) is a tool that endeavors to balance patient flow in the hospital to nursing home chain of care. Results Additional research has indicated that the absence of BM is not the result of providers’ thinking that BM is unnecessary, unethical or impossible because of unpredictable patient flows. Instead, BM is hampered by a lack of cooperation between care providers. Conclusion Although stakeholders recognize that cooperation is imperative, they often fail to take the actions necessary to realize cooperation. Our assumption is that this lack of willingness and ability to cooperate is the result of several impeding conditions as well as stakeholders’ perceptions of these conditions and the persistence of their current routines, principles and beliefs (RPBs). Discussion We recommend simultaneously working on improving the conditions and changing stakeholders’ perceptions and RPBs. PMID:21954373

Rapid Cycle Amine (RCA 2.0) System Development

NASA Technical Reports Server (NTRS)

Papale, William; O'Coin, James; Wichowski, Robert; Chullen, Cinda; Campbell, Colin

2013-01-01

The Rapid Cycle Amine (RCA) system is a low-power assembly capable of simultaneously removing carbon dioxide (CO2) and humidity from an influent air steam and subsequent regeneration when exposed to a vacuum source. Two solid amine sorbent beds are alternated between an uptake mode and a regeneration mode. During the uptake mode, the sorbent is exposed to an air steam (ventilation loop) to adsorb CO2 and water (H2O) vapor, whereas during the regeneration mode, the sorbent rejects the adsorbed CO2 and H2O vapor to a vacuum source. The two beds operate such that while one bed is in the uptake mode, the other is in the regeneration mode, thus continuously providing an on-service sorbent bed by which CO2 and humidity may be removed. A novel valve assembly provides a simple means of diverting the process air flow through the uptake bed while simultaneously directing the vacuum source to the regeneration bed. Additionally, the valve assembly is designed to allow for switching between uptake and regeneration modes with only one moving part while minimizing gas volume losses to the vacuum source by means of an internal pressure equalization step during actuation. The process can be controlled by a compact, low-power controller design with several modes of operation available to the user. Together with NASA Johnson Space Center, Hamilton Sundstrand Space Systems International, Inc. has been developing RCA 2.0 based on performance and design feedback on several sorbent bed test articles and valve design concepts. A final design of RCA 2.0 was selected in November 2011 and fabricated and assembled between March and August 2012, with delivery to NASA Johnson Space Center in September 2012. This paper provides an overview of the RCA system design and results of pre-delivery testing.

Microbial community evolution of black and stinking rivers during in situ remediation through micro-nano bubble and submerged resin floating bed technology.

PubMed

Sun, Yanmei; Wang, Shiwei; Niu, Junfeng

2018-06-01

Microbes play important roles during river remediation and the interaction mechanism illustration between microorganisms and sewage is of great significance to improve restoration technology. In this study, micro-nano bubble and submerged resin floating bed composite technology (MBSR) was firstly used to restore two black and stinking urban rivers. After restoration, the water pollution indices such as dissolved oxygen (DO), ammonia nitrogen (NH 4 + -N), total phosphorous (TP), chemical oxygen demand (COD Cr ), water clarity, and the number of facial coliform were significantly improved. Microbial community composition and relative abundance both varied and more aerobic microbes emerged after remediation. The microbial changes showed correlation with DO, NH 4 + -N, TP and COD Cr of the rivers. In summary, the MBSR treatment improved the physiochemical properties of the two black and stinking urban rivers probably through oxygen enrichment of micro-nano bubble and adsorption of submerged resin floating bed, which thereby stimulated functional microbes to degrade pollutants. Copyright © 2018 Elsevier Ltd. All rights reserved.

From the Gleam in the Eye of an Engineer to a Dream Classroom: How Assistive Technology Products Move from Research and Development into the Hands of Children

ERIC Educational Resources Information Center

de St. Aubin, Shawn-Laree

2010-01-01

This article explains how Asssistive Technology products move from research and development into the hands of children. The assistive technology (AT) industry is maturing, with many exciting new technologies under development in university settings, by individual inventors and engineers, and by leading AT and information technology (IT) companies.…

Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

NASA Astrophysics Data System (ADS)

Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

International Space Station (ISS)

NASA Image and Video Library

1994-09-21

Artist's concept of the final configuration of the International Space Station (ISS) Alpha. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experimentation.

International Space Station (ISS)

NASA Image and Video Library

1994-04-20

An artist's concept of a fully deployed International Space Station (ISS) Alpha. The ISS-A is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experiments.

Numerical simulation of turbulence and sediment transport of medium sand

NASA Astrophysics Data System (ADS)

Schmeeckle, M. W.

2012-12-01

Eleven numerical simulations, ranging from no transport to bedload to vigorous suspension transport, are presented of a combined large eddy simulation (LES) and distinct element model (DEM) of an initially flat bed of medium sand. The fluid and particles are fully coupled in momentum. The friction coefficient, defined here as the squared ratio of the friction velocity to the depth-averaged velocity, is in good agreement with well-known rough bed relations at no transport and increases with the intensity of bedload transport. The friction coefficient nearly doubles in value at the onset of sediment suspension owing to a rapid increase of the depth over which particles and fluid exchange momentum. The friction coefficient decreases with increasing suspension intensity because of increasingly stable stratification. Fluid Reynolds stress and time-averaged velocity profiles in the bedload regime agree well with previous experiments and simulations. Also consistent with previous studies of suspended sediment, there is an increase in slope of the lower portion of the velocity profile that has been modeled in the past using stably stratified eddy viscosity closures or an adjusted von Karman constant. Stokes numbers in the simulations, using an estimated lagrangian integral time scale, are less than unity. As such, particles faithfully follow the fluid, except for particle settling and grain-grain interactions near the bed. Fluid-particle velocity correlation coefficients approach one in portions of the flow where volumetric sediment concentrations are below about ten percent. Bedload entrainment is critically connected to vertical velocity fluctuations. When a fluid packet approaches the bed from the interior of the flow (i.e. a sweep), fluid is forced into the bed, and at the edges of the sweep, fluid is forced out of the bed. Much of the particle entrainment occurs at these sweep edges. Fluid velocity statistics following the particles reveal that moving bedload particles are preferentially concentrated in zones of upward fluid velocity. This may explain previous observations noting a rapid vertical rise at the beginning of saltation trajectories. The simulations described here have no lift forces. Because of the short particle time scales relative to that of the turbulent structures, high transport stage bedload entrainment zones involve mutual interaction between turbulence structures and bed deformation. These deformation structures appear as depressed areas of the bed at the center of the sweep and raised areas of entraining particles at the edges of the sweep penetration. Suspended sediment entrainment structures are similar to these bedload entrainment structures but have much larger scales. Preferential concentration of suspended grains in zones of upward moving fluid dampens turbulence intensities and momentum transport. Much of the suspended transport takes place within this highly concentrated near-bed zone of damped turbulence. Particle-fluid correlation coefficients are relatively low in the lower portion of this highly concentrated suspended sediment zone, owing to particle-particle interactions. As such, Rouse-like profiles utilizing eddy viscosity closures, adjusted according to flux Richardson numbers, do not adequately describe the physics of this zone.

Underwater microscope for measuring spatial and temporal changes in bed-sediment grain size

USGS Publications Warehouse

Rubin, David M.; Chezar, Henry; Harney, Jodi N.; Topping, David J.; Melis, Theodore S.; Sherwood, Christopher R.

2007-01-01

For more than a century, studies of sedimentology and sediment transport have measured bed-sediment grain size by collecting samples and transporting them back to the laboratory for grain-size analysis. This process is slow and expensive. Moreover, most sampling systems are not selective enough to sample only the surficial grains that interact with the flow; samples typically include sediment from at least a few centimeters beneath the bed surface. New hardware and software are available for in situ measurement of grain size. The new technology permits rapid measurement of surficial bed sediment. Here we describe several systems we have deployed by boat, by hand, and by tripod in rivers, oceans, and on beaches.

Underwater Microscope for Measuring Spatial and Temporal Changes in Bed-Sediment Grain Size

USGS Publications Warehouse

Rubin, David M.; Chezar, Henry; Harney, Jodi N.; Topping, David J.; Melis, Theodore S.; Sherwood, Christopher R.

2006-01-01

For more than a century, studies of sedimentology and sediment transport have measured bed-sediment grain size by collecting samples and transporting them back to the lab for grain-size analysis. This process is slow and expensive. Moreover, most sampling systems are not selective enough to sample only the surficial grains that interact with the flow; samples typically include sediment from at least a few centimeters beneath the bed surface. New hardware and software are available for in-situ measurement of grain size. The new technology permits rapid measurement of surficial bed sediment. Here we describe several systems we have deployed by boat, by hand, and by tripod in rivers, oceans, and on beaches.

"The swarming of life": moving images, education, and views through the microscope.

PubMed

Gaycken, Oliver

2011-09-01

Discussions of the scientific uses of moving-image technologies have emphasized applications that culminated in static images, such as the chronophotographic decomposition of movement into discrete and measurable instants. The projection of movement, however, was also an important capability of moving-image technologies that scientists employed in a variety of ways. Views through the microscope provide a particularly sustained and prominent instance of the scientific uses of the moving image. The category of "education" subsumes theses various scientific uses, providing a means by which to bridge the cultures of scientific and popular scientific moving images.

Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control

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

Nsakala ya Nsakala; Gregory N. Liljedahl; David G. Turek

2007-03-31

Given that fossil fuel fired power plants are among the largest and most concentrated producers of CO{sub 2} emissions, recovery and sequestration of CO{sub 2} from the flue gas of such plants has been identified as one of the primary means for reducing anthropogenic (i.e., man-made) CO{sub 2} emissions. In 2001, ALSTOM Power Inc. (ALSTOM) began a two-phase program to investigate the feasibility of various carbon capture technologies. This program was sponsored under a Cooperative Agreement from the US Department of Energy's National Energy Technology Laboratory (DOE). The first phase entailed a comprehensive study evaluating the technical feasibility and economicsmore » of alternate CO{sub 2} capture technologies applied to Greenfield US coal-fired electric generation power plants. Thirteen cases, representing various levels of technology development, were evaluated. Seven cases represented coal combustion in CFB type equipment. Four cases represented Integrated Gasification Combined Cycle (IGCC) systems. Two cases represented advanced Chemical Looping Combined Cycle systems. Marion, et al. reported the details of this work in 2003. One of the thirteen cases studied utilized an oxygen-fired circulating fluidized bed (CFB) boiler. In this concept, the fuel is fired with a mixture of oxygen and recirculated flue gas (mainly CO{sub 2}). This combustion process yields a flue gas containing over 80 percent (by volume) CO{sub 2}. This flue gas can be processed relatively easily to enrich the CO{sub 2} content to over 96 percent for use in enhanced oil or gas recovery (EOR or EGR) or simply dried for sequestration. The Phase I study identified the O{sub 2}-fired CFB as having a near term development potential, because it uses conventional commercial CFB technology and commercially available CO{sub 2} capture enabling technologies such as cryogenic air separation and simple rectification or distillation gas processing systems. In the long term, air separation technology advancements offer significant reductions in power requirements, which would improve plant efficiency and economics for the oxygen-fired technology. The second phase consisted of pilot-scale testing followed by a refined performance and economic evaluation of the O{sub 2} fired CFB concept. As a part of this workscope, ALSTOM modified its 3 MW{sub th} (9.9 MMBtu/hr) Multiuse Test Facility (MTF) pilot plant to operate with O{sub 2}/CO{sub 2} mixtures of up to 70 percent O{sub 2} by volume. Tests were conducted with coal and petroleum coke. The test objectives were to determine the impacts of oxygen firing on heat transfer, bed dynamics, potential agglomeration, and gaseous and particulate emissions. The test data results were used to refine the design, performance, costs, and economic models developed in Phase-I for the O{sub 2}-fired CFB with CO{sub 2} capture. Nsakala, Liljedahl, and Turek reported results from this study in 2004. ALSTOM identified several items needing further investigation in preparation for large scale demonstration of the oxygen-fired CFB concept, namely: (1) Operation and performance of the moving bed heat exchanger (MBHE) to avoid recarbonation and also for cost savings compared to the standard bubbling fluid bed heat exchanger (FBHE); (2) Performance of the back-end flash dryer absorber (FDA) for sulfur capture under high CO{sub 2}/high moisture flue gas environment using calcined limestone in the fly ash and using fresh commercial lime directly in the FDA; (3) Determination of the effect of recarbonation on fouling in the convective pass; (4) Assessment of the impact of oxygen firing on the mercury, other trace elements, and volatile organic compound (VOC) emissions; and (5) Develop a proposal-level oxygen-fired retrofit design for a relatively small existing CFB steam power plant in preparation for a large-scale demonstration of the O{sub 2} fired CFB concept. Hence, ALSTOM responded to a DOE Solicitation to address all these issues with further O{sub 2} fired MTF pilot testing and a subsequent retrofit design study of oxygen firing and CO{sub 2} capture on an existing air-fired CFB plant. ALSTOM received a contract award from the DOE to conduct a project entitled 'Commercialization Development of Oxygen Fired CFB for Greenhouse Gas Control', under Cooperative Agreement DE-FC26-04NT42205 that is the subject of this topical report.« less

Experimental Bedrock Channel Incision: Scaling, Sculpture and Sediment Transport

NASA Astrophysics Data System (ADS)

Johnson, J. P.; Whipple, K. X.

2004-12-01

Abrasion by sediment in turbulent flows often sculpts bedrock channels into dramatic forms; quantifying the feedbacks between fluid flow, sediment impacts, and channel morphology is needed to refine models of fluvial incision into bedrock. We present data from laboratory flume experiments funded by the National Center for Earth-Surface Dynamics and conducted at St. Anthony Falls Laboratory, University of Minnesota that show how the spatial and temporal distribution of erosion is strongly coupled to the evolving topography of the bed. These experiments focus on the high Froude number and tool-starved end of parameter space, where bed cover tends to be negligible. Independent variables include flume slope, water flux and sediment flux and size distribution. Sediment moves energetically as bedload, suspended load, or locally transitional between transport modes. Quantitative measurements of the evolving bed topography show that the synthetic brittle "bedrock" in the flume (cured sand-cement mixture) eroded to form narrow incised channels with tight scoops and potholes. The experimental erosional forms are similar in morphology, and sometimes in scale, to those observed in natural bedrock rivers in southeast Utah and other field settings. The experiments demonstrate that both the mean and distribution of measured erosion rates change as the bed topography evolves, even with constant water and sediment discharges. Even starting with a plane bed geometry, erosion and sediment transport very quickly become localized in interconnected topographic lows. Positive feedback develops between the evolving topography and the fluid velocity and sediment transport fields, resulting in the incision of an inner channel. Once formed, the erosion rate in the axis of the inner channel decreases as local bed shear stresses and fluid velocities are reduced by increasing wall drag, and sediment fluxes through the channel but causes less incision (no deposition). Decreasing the sediment flux (all else held equal) causes renewed incision, but of an even narrower inner channel; increasing the sediment flux leads to inner channel deposition. Where erosion is most vigorous, sediment generally moving as saltating bedload becomes locally suspended by upward-directed mean flow. For example, swirling clouds of "bedload" particles are continuously suspended by vortices developed within potholes such that the upward flux of particles out of the potholes balance the total sediment flux through the flume. Potholes spontaneously form where average bed slope and fluid velocities were highest, dramatically accelerating the local erosion rate. Our experimental potholes are smaller in scale but morphologically strikingly similar to many observed in the field, and include features such as corkscrew grooves down the outside walls and a protruding horn at the pothole center. More generally, abrasion becomes focused in places where the flow is spatially accelerated, such as in scoops and bends with high curvature. The knife-edge margins and spatial distribution of erosional forms indicate abrupt transitions in erosional efficiency that are tightly coupled to near-bed fluid flow patterns, which in turn are strongly influenced by the erosional forms themselves. Our experiments suggest that, in highly sculpted bedrock channels, naturally developed bed roughness presents a physical length scale that is important to controlling the interaction between sediment impacts and the bed, rather than a length scale based explicitly on sediment transport and average flow conditions such as the saltation hop length.

High-speed image transmission via the Advanced Communication Technology Satellite (ACTS)

NASA Astrophysics Data System (ADS)

Bazzill, Todd M.; Huang, H. K.; Thoma, George R.; Long, L. Rodney; Gill, Michael J.

1996-05-01

We are developing a wide area test bed network using the Advanced Communication Technology Satellite (ACTS) from NASA for high speed medical image transmission. The two test sites are the University of California, San Francisco, and the National Library of Medicine. The first phase of the test bed runs over a T1 link (1.544 Mbits/sec) using a Very Small Aperture Terminal. The second phase involves the High Data Rate Terminal via an ATM OC 3C (155 Mbits/sec) connection. This paper describes the experimental set up and some preliminary results from phase 1.

U.S. Geological Survey research on surrogate measurements for suspended sediment

USGS Publications Warehouse

Gray, John R.; Melis, Theodore S.; Patiño, Eduardo; Larsen, Matthew C.; Topping, David J.; Rasmussen, Patrick P.; Figueroa-Alamo, Carlos

2003-01-01

The U.S. Geological Survey is evaluating potentially useful surrogate instruments and methods for inferring the physical characteristics of suspended sediments. Instruments operating on bulk acoustic, bulk and digital optic, laser, and pressure-differential technologies are being tested in riverine and laboratory settings for their usefulness to Federal agencies toward providing quantifiably reliable information on bed-material and bed-topography characteristics, and on concentrations, size distributions and transport rates of sediments in suspension and as bedload. The efficacy of four suspended-sediment surrogate technologies has been demonstrated to varying degrees of success in Kansas, Florida, Arizona, and Puerto Rico.

Advanced expander test bed engine

NASA Technical Reports Server (NTRS)

Mitchell, J. P.

1992-01-01

The Advanced Expander Test Bed (AETB) is a key element in NASA's Space Chemical Engine Technology Program for development and demonstration of expander cycle oxygen/hydrogen engine and advanced component technologies applicable to space engines as well as launch vehicle upper stage engines. The AETB will be used to validate the high pressure expander cycle concept, study system interactions, and conduct studies of advanced mission focused components and new health monitoring techniques in an engine system environment. The split expander cycle AETB will operate at combustion chamber pressures up to 1200 psia with propellant flow rates equivalent to 20,000 lbf vacuum thrust.

Fluidized bed combustor 50 MW thermal power plant, Krabi, Thailand. Feasibility study. Export trade information

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

Not Available

The report presents the results of a study prepared by Burns and Roe for the Electricity Generating Authority of Thailand to examine the technical feasibility and economic attractiveness for building a 50 MW Atmospheric Fluidized Bed Combustion lignite fired power plant at Krabi, southern Thailand. The study is divided into seven main sections, plus an executive summary and appendices: (1) Introduction; (2) Atmospheric Fluidized Bed Combustion Technology Overview; (3) Fuel and Limestone Tests; (4) Site Evaluation; (5) Station Design and Arrangements; (6) Environmental Considerations; (7) Economic Analysis.

Bedload and river hydraulics - Inferences from the East Fork River, Wyoming

USGS Publications Warehouse

Leopold, Luna Bergere; Emmett, William W.

1997-01-01

During 1973-79, bedload data were collected in a sophisticated trap on a river of moderate size, the East Fork. The transport rate was measured most days through a full snowmelt season, and the rate was determined separately for eight zones across the channel width. The quantitative data are unique and unlikely to be repeated. Nor need they be, because as a result of this effort a practical bedload sampler was adequately tested against full river measurement.It was shown that bedload moves sporadically and randomly on the river bed. Therefore, transport rate is highly variable in short periods of time. There is also a wide variance from day to day. Yet, different rivers have transport rates, which are functions of discharge, depth, and sediment size, that are clearly distinct. Comparison of computed and measured transport rates indicates that a major problem remains: What grain size is representative of the bedload when there is a wide or heterogeneous particle-size distribution? Size of the bedload in motion may be very different from the size of bed material obtained from samples of the streambed.For general computation, the river channel slope may be averaged, and it may be assumed that water-surface slope does not change materially with changing discharge. Indeed, this generality is correct, in that, compared with depth, velocity, and width, slope is conservative at-a-station. However, in more detail, slope changes importantly with discharge in short reaches of channel, and those changes are very different in pool and riffle.These local changes in slope are not merely an aspect of a detailed longitudinal profile but involve cross-channel as well as down-channel components. The pool and riffle sequence involves not only undulation of bed elevation and bar formation on alternate sides of the channel, but alternation of the zone of superovulation of the water surface, and changing relation of watersurface slope to discharge. These details can be seen only in the full topography of the water surface. Riffles fill during high flow and scour at low flow. Changes in local water-surface slope illustrate this process. Pools are a storage zone for sediment in the low-flow season. Even though large volumes of sediment move, the distance moved is not large—in the East Fork River, sand of size 0.5-1 millimeter moved 650 meters during the 1979 snowmelt runoff season.Bedload transport is greatest over or near bars and not in the deepest part of the channel. Direct observation of the locus of sediment transport indicates that this locus moves from one side of the channel to the other in concert with the occurrence of alternate bars. Separately, data indicate that at constant stream power, transport rate increases as depth decreases.

Research on measurement method of optical camouflage effect of moving object

NASA Astrophysics Data System (ADS)

Wang, Juntang; Xu, Weidong; Qu, Yang; Cui, Guangzhen

2016-10-01

Camouflage effectiveness measurement as an important part of the camouflage technology, which testing and measuring the camouflage effect of the target and the performance of the camouflage equipment according to the tactical and technical requirements. The camouflage effectiveness measurement of current optical band is mainly aimed at the static target which could not objectively reflect the dynamic camouflage effect of the moving target. This paper synthetical used technology of dynamic object detection and camouflage effect detection, the digital camouflage of the moving object as the research object, the adaptive background update algorithm of Surendra was improved, a method of optical camouflage effect detection using Lab-color space in the detection of moving-object was presented. The binary image of moving object is extracted by this measurement technology, in the sequence diagram, the characteristic parameters such as the degree of dispersion, eccentricity, complexity and moment invariants are constructed to construct the feature vector space. The Euclidean distance of moving target which through digital camouflage was calculated, the results show that the average Euclidean distance of 375 frames was 189.45, which indicated that the degree of dispersion, eccentricity, complexity and moment invariants of the digital camouflage graphics has a great difference with the moving target which not spray digital camouflage. The measurement results showed that the camouflage effect was good. Meanwhile with the performance evaluation module, the correlation coefficient of the dynamic target image range 0.1275 from 0.0035, and presented some ups and down. Under the dynamic condition, the adaptability of target and background was reflected. In view of the existing infrared camouflage technology, the next step, we want to carry out the camouflage effect measurement technology of the moving target based on infrared band.

Envisioning New Technologies in Teacher Practice: Moving Forward, Circling Back Using a Teacher Action Research Approach. New Literacies and Digital Epistemologies. Volume 47

ERIC Educational Resources Information Center

Strong-Wilson, Teresa, Ed.

2012-01-01

How do classroom teachers envision new technologies within their practice? In the conversation on incorporating new technologies into classrooms, teachers are often sidelined. "Envisioning New Technologies in Teacher Practice" looks at the complex ways in which teachers move forward to embrace change as well as how they circle back, continually…

The impact of benthic fauna on fluvial bed load transport: Challenges of upscaling laboratory experiments to river and landscape scales.

NASA Astrophysics Data System (ADS)

Rice, S. P.

2012-04-01

The impact on sediment transport processes and channel morphology of several relatively large, iconic animals including beaver and salmon is increasingly well understood. However, many other aquatic fauna are important zoogeomorphic agents and ecosystem engineers. These somewhat overlooked "Cinderella" species include benthic aquatic insect larvae, freshwater crustaceans and many species of fish. Despite relatively modest individual effects, the ubiquity, abundance and cumulative impact of these organisms makes them a potentially significant agency, with as yet undiscovered and unquantified impacts on channel morphology and sediment fluxes. Their actions (digging, foraging, moving, burrowing), constructions and secretions modify bed sediment characteristics (grain size distribution, interlock, imbrication, protrusion), alter bed topography (thence hydraulic roughness) and contribute to biogenic restraints on grain movement. In turn, they can affect the distribution of surface particle entrainment thresholds and bed shear stresses, with implications for bed load transport. Flume experiments have measured some of these impacts and provided direct observations of the mechanisms involved, but many of the most interesting research questions pertain to the impact of these animals at reach, catchment and even landscape scales: Not least, what is the impact of small aquatic animals on bed load flux and yield? This presentation will consider some of the challenges involved in answering this question; that is, of scaling up experimental understanding of how aquatic animals affect bed load transport processes to river scales. Pertinent themes include: (1) the potential impacts of experimental arrangements on the behaviours and activities that affect hydraulic or geomorphological processes; (2) field coincidence of the spatial and temporal distributions of (a) the animals and their behaviours with (b) the physical conditions (substrates, flows) under which those animals are understood to have an effect; (3) the magnitude of any demonstrable net field impact, relative to those other factors that control bed load transport rates.

Mathematical modelling of sewage sludge incineration in a bubbling fluidised bed with special consideration for thermally-thick fuel particles.

PubMed

Yang, Yao Bin; Sharifi, Vida; Swithenbank, Jim

2008-11-01

Fluidised bed combustor (FBC) is one of the key technologies for sewage sludge incineration. In this paper, a mathematical model is developed for the simulation of a large-scale sewage sludge incineration plant. The model assumes the bed consisting of a fast-gas phase, an emulsion phase and a fuel particle phase with specific consideration for thermally-thick fuel particles. The model further improves over previous works by taking into account throughflow inside the bubbles as well as the floating and random movement of the fuel particles inside the bed. Validation against both previous lab-scale experiments and operational data of a large-scale industrial plant was made. Calculation results indicate that combustion split between the bed and the freeboard can range from 60/40 to 90/10 depending on the fuel particle distribution across the bed height under the specific conditions. The bed performance is heavily affected by the variation in sludge moisture level. The response time to variation in feeding rate is different for different parameters, from 6 min for outlet H2O, 10 min for O2, to 34 min for bed temperature.

Fluidized bed gasification of industrial solid recovered fuels.

PubMed

Arena, Umberto; Di Gregorio, Fabrizio

2016-04-01

The study evaluates the technical feasibility of the fluidized bed gasification of three solid recovered fuels (SRFs), obtained as co-products of a recycling process. The SRFs were pelletized and fed to a pilot scale bubbling fluidized bed reactor, operated in gasification and co-gasification mode. The tests were carried out under conditions of thermal and chemical steady state, with a bed of olivine particles and at different values of equivalence ratio. The results provide a complete syngas characterization, in terms of its heating value and composition (including tars, particulates, and acid/basic pollutants) and of the chemical and physical characterization of bed material and entrained fines collected at the cyclone outlet. The feasibility of the fluidized bed gasification process of the different SRFs was evaluated with the support of a material and substance flow analysis, and a feedstock energy analysis. The results confirm the flexibility of fluidized bed reactor, which makes it one of the preferable technologies for the gasification of different kind of wastes, even in co-gasification mode. The fluidized bed gasification process of the tested SRFs appears technically feasible, yielding a syngas of valuable quality for energy applications in an appropriate plant configuration. Copyright © 2016 Elsevier Ltd. All rights reserved.

FSA future directions: FSA technology activities in FY86

NASA Technical Reports Server (NTRS)

Leipold, M. H.

1985-01-01

The silicon material, advanced silicon sheet, device research, and process research activities are explained. There will be no new initiatives. Many activities are targeted for completion and the emphasis will then be on technology transfer. Industrial development of the fluidized-bed reactor (FBR) deposition technology is proceeding. Technology transfer and industry funding of sheet development are continuing.

Moving Target Techniques: Leveraging Uncertainty for CyberDefense

DTIC Science & Technology

2015-12-15

cyberattacks is a continual struggle for system managers. Attackers often need only find one vulnerability (a flaw or bug that an attacker can exploit...additional parsing code itself could have security-relevant software bugs . Dynamic  Network   Techniques in the dynamic network domain change the...evaluation of MT techniques can benefit from a variety of evaluation approaches, including abstract analysis, modeling and simulation, test bed

Effects of alkalinity on ammonia removal, carbon dioxide stripping, and system pH in semi-commercial scale water recirculating aquaculture systems operated with moving bed bioreactors

USDA-ARS?s Scientific Manuscript database

When operating water recirculating systems (RAS) with high make-up water flushing rates in locations that have low alkalinity in the raw water, such as Norway, knowledge about the required RAS alkalinity concentration is important. Flushing RAS with make-up water containing low alkalinity washes out...

Move to outpatient settings may boost medical hotels.

PubMed

Burns, J

1992-06-08

The shift of surgeries to outpatient settings could be healthy for medical hotels, those amenity-equipped facilities originally developed to ease patients out of costly acute-care beds. Because fewer hospitals have a pressing need to use such alternative lodging, some medical hotels are hoping to hitch their fortunes to the outpatient trade, keeping patients overnight after surgeries that don't require hospital admission.

Development of Additional Hazard Assessment Models

DTIC Science & Technology

1977-03-01

globules, their trajectory (the distance from the spill point to the impact point on the river bed), and the time required for sinking. Established theories ...chemicals, the dissolution rate is estimated by using eddy diffusivity surface renewal theories . The validity of predictions of these theories has been... theories and experimental data on aeration of rivers. * Describe dispersion in rivers with stationary area source and sources moving with the stream

Missouri gravel bed and a pot-in-pot system superior to white polyethylene and foam for overwintering Syringa pubescens subsp patula Liners

Treesearch

Steven D. Kirk; Chris J. Starbuck; J.W. Van Sambeek

2004-01-01

The production of containerized nursery stock started in southern California because of its mild climate and long growing season (Whitcomb, 1987). As production of containerized stock moved into areas of the country with harsher climates, methods of overwintering were developed to protect plants from winter damage. Proper winter protection in the production of...

A Successful Model for a Comprehensive Patient Flow Management Center at an Academic Health System.

PubMed

Lovett, Paris B; Illg, Megan L; Sweeney, Brian E

2016-05-01

This article reports on an innovative approach to managing patient flow at a multicampus academic health system, integrating multiple services into a single, centralized Patient Flow Management Center that manages supply and demand for inpatient services across the system. Control of bed management was centralized across 3 campuses and key services were integrated, including bed management, case management, environmental services, patient transport, ambulance and helicopter dispatch, and transfer center. A single technology platform was introduced, as was providing round-the-clock patient placement by critical care nurses, and adding medical directors. Daily bed meetings with nurse managers and charge nurses drive action plans. This article reports immediate improvements in the first year of operations in emergency department walkouts, emergency department boarding, ambulance diversion, growth in transfer volume, reduction in lost transfers, reduction in time to bed assignment, and bed turnover time. The authors believe theirs is the first institution to integrate services and centralize bed management so comprehensively. © The Author(s) 2014.

Space station propulsion test bed

NASA Technical Reports Server (NTRS)

Briley, G. L.; Evans, S. A.

1989-01-01

A test bed was fabricated to demonstrate hydrogen/oxygen propulsion technology readiness for the intital operating configuration (IOC) space station application. The test bed propulsion module and computer control system were delivered in December 1985, but activation was delayed until mid-1986 while the propulsion system baseline for the station was reexamined. A new baseline was selected with hydrogen/oxygen thruster modules supplied with gas produced by electrolysis of waste water from the space shuttle and space station. As a result, an electrolysis module was designed, fabricated, and added to the test bed to provide an end-to-end simulation of the baseline system. Subsequent testing of the test bed propulsion and electrolysis modules provided an end-to-end demonstration of the complete space station propulsion system, including thruster hot firings using the oxygen and hydrogen generated from electrolysis of water. Complete autonomous control and operation of all test bed components by the microprocessor control system designed and delivered during the program was demonstrated. The technical readiness of the system is now firmly established.

Multi-objective optimization for the economic production of d-psicose using simulated moving bed chromatography.

PubMed

Wagner, N; Håkansson, E; Wahler, S; Panke, S; Bechtold, M

2015-06-12

The biocatalytic production of rare carbohydrates from available sugar sources rapidly gains interest as a route to acquire industrial amounts of rare sugars for food and fine chemical applications. Here we present a multi-objective optimization procedure for a simulated moving bed (SMB) process for the production of the rare sugar d-psicose from enzymatically produced mixtures with its epimer d-fructose. First, model parameters were determined using the inverse method and experimentally validated on a 2-2-2-2 lab-scale SMB plant. The obtained experimental purities (PUs) were in excellent agreement with the simulated data derived from a transport-dispersive true-moving bed model demonstrating the feasibility of the proposed design. In the second part the performance of the separation was investigated in a multi-objective optimization study addressing the cost-contributing performance parameters productivity (PR) and desorbent requirement (DR) as a function of temperature. While rare sugar SMB operation under conditions of low desorbent consumption was found to be widely unaffected by temperature, SMB operation focusing on increased PR significantly benefited from high temperatures, with possible productivities increasing from 3.4kg(Lday)(-1) at 20°C to 5kg(Lday)(-1) at 70°C, indicating that decreased selectivity at higher temperatures could be fully compensated for by the higher mass transfer rates, as they translate into reduced switch times and hence higher PR. A DR/PR Pareto optimization suggested a similar but even more pronounced trend also under relaxed PU requirements, with the PR increasing from 4.3kg(Lday)(-1) to a maximum of 7.8kg(Lday)(-1) for SMB operation at 50°C when the PU of the non-product stream was reduced from 99.5% to 90%. Based on the in silico optimization results experimental SMB runs were performed yielding considerable PRs of 1.9 (30°C), 2.4 (50°C) and 2.6kg(Lday)(-1) (70°C) with rather low DR (27L per kg of rare sugar produced) on a lab-scale SMB installation. Copyright © 2015. Published by Elsevier B.V.

Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments.

PubMed

Liu, Wen; Fu, Xiao; Deng, Zhongliang

2016-12-02

Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS). Due to the absence of satellite signal in Global Navigation Satellite System (GNSS), various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP), which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC), is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1) and the XiDan Joy City (Floors 1 and 2, as Test-bed 2), and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means.

Coordinate-Based Clustering Method for Indoor Fingerprinting Localization in Dense Cluttered Environments

PubMed Central

Liu, Wen; Fu, Xiao; Deng, Zhongliang

2016-01-01

Indoor positioning technologies has boomed recently because of the growing commercial interest in indoor location-based service (ILBS). Due to the absence of satellite signal in Global Navigation Satellite System (GNSS), various technologies have been proposed for indoor applications. Among them, Wi-Fi fingerprinting has been attracting much interest from researchers because of its pervasive deployment, flexibility and robustness to dense cluttered indoor environments. One challenge, however, is the deployment of Access Points (AP), which would bring a significant influence on the system positioning accuracy. This paper concentrates on WLAN based fingerprinting indoor location by analyzing the AP deployment influence, and studying the advantages of coordinate-based clustering compared to traditional RSS-based clustering. A coordinate-based clustering method for indoor fingerprinting location, named Smallest-Enclosing-Circle-based (SEC), is then proposed aiming at reducing the positioning error lying in the AP deployment and improving robustness to dense cluttered environments. All measurements are conducted in indoor public areas, such as the National Center For the Performing Arts (as Test-bed 1) and the XiDan Joy City (Floors 1 and 2, as Test-bed 2), and results show that SEC clustering algorithm can improve system positioning accuracy by about 32.7% for Test-bed 1, 71.7% for Test-bed 2 Floor 1 and 73.7% for Test-bed 2 Floor 2 compared with traditional RSS-based clustering algorithms such as K-means. PMID:27918454

Design and Analysis of Embedded I&C for a Fully Submerged Magnetically Suspended Impeller Pump

DOE PAGES

Melin, Alexander M.; Kisner, Roger A.

2018-04-03

Improving nuclear reactor power system designs and fuel-processing technologies for safer and more efficient operation requires the development of new component designs. In particular, many of the advanced reactor designs such as the molten salt reactors and high-temperature gas-cooled reactors have operating environments beyond the capability of most currently available commercial components. To address this gap, new cross-cutting technologies need to be developed that will enable design, fabrication, and reliable operation of new classes of reactor components. The Advanced Sensor Initiative of the Nuclear Energy Enabling Technologies initiative is investigating advanced sensor and control designs that are capable of operatingmore » in these extreme environments. Under this initiative, Oak Ridge National Laboratory (ORNL) has been developing embedded instrumentation and control (I&C) for extreme environments. To develop, test, and validate these new sensing and control techniques, ORNL is building a pump test bed that utilizes submerged magnetic bearings to levitate the shaft. The eventual goal is to apply these techniques to a high-temperature (700°C) canned rotor pump that utilizes active magnetic bearings to eliminate the need for mechanical bearings and seals. The technologies will benefit the Next Generation Power Plant, Advanced Reactor Concepts, and Small Modular Reactor programs. In this paper, we will detail the design and analysis of the embedded I&C test bed with submerged magnetic bearings, focusing on the interplay between the different major systems. Then we will analyze the forces on the shaft and their role in the magnetic bearing design. Next, we will develop the radial and thrust bearing geometries needed to meet the operational requirements of the test bed. In conclusion, we will present some initial system identification results to validate the theoretical models of the test bed dynamics.« less

Design and Analysis of Embedded I&C for a Fully Submerged Magnetically Suspended Impeller Pump

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

Melin, Alexander M.; Kisner, Roger A.

Improving nuclear reactor power system designs and fuel-processing technologies for safer and more efficient operation requires the development of new component designs. In particular, many of the advanced reactor designs such as the molten salt reactors and high-temperature gas-cooled reactors have operating environments beyond the capability of most currently available commercial components. To address this gap, new cross-cutting technologies need to be developed that will enable design, fabrication, and reliable operation of new classes of reactor components. The Advanced Sensor Initiative of the Nuclear Energy Enabling Technologies initiative is investigating advanced sensor and control designs that are capable of operatingmore » in these extreme environments. Under this initiative, Oak Ridge National Laboratory (ORNL) has been developing embedded instrumentation and control (I&C) for extreme environments. To develop, test, and validate these new sensing and control techniques, ORNL is building a pump test bed that utilizes submerged magnetic bearings to levitate the shaft. The eventual goal is to apply these techniques to a high-temperature (700°C) canned rotor pump that utilizes active magnetic bearings to eliminate the need for mechanical bearings and seals. The technologies will benefit the Next Generation Power Plant, Advanced Reactor Concepts, and Small Modular Reactor programs. In this paper, we will detail the design and analysis of the embedded I&C test bed with submerged magnetic bearings, focusing on the interplay between the different major systems. Then we will analyze the forces on the shaft and their role in the magnetic bearing design. Next, we will develop the radial and thrust bearing geometries needed to meet the operational requirements of the test bed. In conclusion, we will present some initial system identification results to validate the theoretical models of the test bed dynamics.« less

Sediment Transport Processes During Flood Events in the Middle LoireGauging and First Results

NASA Astrophysics Data System (ADS)

Gautier, J.; Rodrigues, S.; Juge, P.; Peters, J.

2008-12-01

A hydraulic and sediment transport survey campaign was organised in March 2007 on the Loire River, at the Bréhémont site. The aim was to collect data useful for the understanding of fluviomorphological mechanisms. A survey procedure, established at the end of the 1960's and relying on a follow-up bathymetric surveys and ancient sediments samplers was combined with modern technologies such as DGPS satellite positioning and ADCP flow gauging. The survey campaign allowed quantifying the sediment transport rates of the size fractions larger than 50 microns. The results confirm the earlier made hypothesis concerning the existence of a sediment load moving close to the bottom and distinct from the suspended load as described in the theories. This load was called "morphological" and is composed of solids having sizes between those of the river bed and those moving in suspension at higher elevations. This statement, made on the basis of surveys on other large streams in Africa, Asia and the America's questions the concepts on which have been based the majority of the sediment transport theories. The analysis shows also that the rate of bedload transport can be very high up to 60% in some verticals and nearly 50% on all a profil, that is much more than the rate usually admits. The present surveys show that campaigns as these are necessary in order to comprehend the processes, a condition prior to investigating solutions.

Aspects of design, structure, performance and operation of reed beds--eight years' experience in northeastern New South Wales, Australia.

PubMed

Davison, L; Headley, T; Pratt, K

2005-01-01

Reed beds (horizontal subsurface flow constructed wetlands) have been employed as secondary treatment devices in on-site and decentralised wastewater management systems in the northeast of the Australian state of New South Wales (NSW) for over a decade. This paper summarises some of the practical and research findings that have come to light in that time. Experience with various aspects of reed bed structure is discussed. A study of the evaporative performance of four small beds planted with Phragmites australis yielded an annual crop factor of 2.6. A total of 28 studies on reed beds treating a variety of commonly encountered wastewater streams yielded the following mean pollutant removal efficiencies: total suspended solids (TSS) 83%, biochemical oxygen demand (BOD) 81%, total nitrogen (TN) 57%, total phosphorus (TP) 35% and faecal coliforms (FC) 1.9 logs. The reed bed is becoming the preferred on-site technology for removing TN and BOD and polishing TSS from primary settled domestic wastewater. Sizing beds for a residence time of approximately five days has become standard practice. A study of six reed beds found six different species of earthworm present, mainly Perionyx excavatus (Indian Blue). A mesocosm experiment subsequently showed that the worms were translocating clogging material from the substrate interstices to the surface of the bed thereby indicating a possible method for prolonging reed bed life.

A review on equipped hospital beds with wireless sensor networks for reducing bedsores

PubMed Central

Ajami, Sima; Khaleghi, Lida

2015-01-01

At present, the solutions to prevent bedsore include using various techniques for movement and displacement of patients, which is not possible for some patients or dangerous for some of them while it also poses problems for health care providers. On the other hand, development of information technology in the health care system including application of wireless sensor networks (WSNs) has led to easy and quick service-providing. It can provide a solution to prevent bedsore in motionless and disabled patients. Hence, the aim of this article was first to introduce WSNs in hospital beds and second, to identify the benefits and challenges in implementing this technology. This study was a nonsystematic review. The literature was searched for WSNs to reduce and prevent bedsores with the help of libraries, databases (PubMed, SCOPUS, and EMBASE), and also searches engines available at Google Scholar including during 1974-2014 while the inclusion criteria were applied in English and Persian. In our searches, we employed the following keywords and their combinations: “wireless sensor network,” “smart bed,” “information technology,” “smart mattress,” and “bedsore” in the searching areas of titles, keywords, abstracts, and full texts. In this study, more than 45 articles and reports were collected and 37 of them were selected based on their relevance. Therefore, identification and implementation of this technology will be a step toward mechanization of traditional procedures in providing care for hospitalized patients and disabled people. The smart bed and mattress, either alone or in combination with the other technologies, should be capable of providing all of the novel features while still providing the comfort and safety features usually associated with traditional and hospital mattresses. It can eliminate the expense of bedsore in the intensive care unit (ICU) department in the hospital and save much expense there. PMID:26929768

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

NASA Technical Reports Server (NTRS)

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

2013-01-01

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.

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

NASA Technical Reports Server (NTRS)

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

2012-01-01

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.

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

NASA Technical Reports Server (NTRS)

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

2011-01-01

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.

Formulating food protein-stabilized indomethacin nanosuspensions into pellets by fluid-bed coating technology: physical characterization, redispersibility, and dissolution

PubMed Central

He, Wei; Lu, Yi; Qi, Jianping; Chen, Lingyun; Yin, Lifang; Wu, Wei

2013-01-01

Background Drug nanosuspensions are very promising for enhancing the dissolution and bioavailability of drugs that are poorly soluble in water. However, the poor stability of nanosuspensions, reflected in particle growth, aggregation/agglomeration, and change in crystallinity state greatly limits their applications. Solidification of nanosuspensions is an ideal strategy for addressing this problem. Hence, the present work aimed to convert drug nanosuspensions into pellets using fluid-bed coating technology. Methods Indomethacin nanosuspensions were prepared by the precipitation-ultrasonication method using food proteins (soybean protein isolate, whey protein isolate, β-lactoglobulin) as stabilizers. Dried nanosuspensions were prepared by coating the nanosuspensions onto pellets. The redispersibility, drug dissolution, solid-state forms, and morphology of the dried nanosuspensions were evaluated. Results The mean particle size for the nanosuspensions stabilized using soybean protein isolate, whey protein isolate, and β-lactoglobulin was 588 nm, 320 nm, and 243 nm, respectively. The nanosuspensions could be successfully layered onto pellets with high coating efficiency. Both the dried nanosuspensions and nanosuspensions in their original amorphous state and not influenced by the fluid-bed coating drying process could be redispersed in water, maintaining their original particle size and size distribution. Both the dried nanosuspensions and the original drug nanosuspensions showed similar dissolution profiles, which were both much faster than that of the raw crystals. Conclusion Fluid-bed coating technology has potential for use in the solidification of drug nanosuspensions. PMID:23983465

Towards an autonomous telescope system: the Test-Bed Telescope project

NASA Astrophysics Data System (ADS)

Racero, E.; Ocaña, F.; Ponz, D.; the TBT Consortium

2015-05-01

In the context of the Space Situational Awareness (SSA) programme of ESA, it is foreseen to deploy several large robotic telescopes in remote locations to provide surveillance and tracking services for man-made as well as natural near-Earth objects (NEOs). The present project, termed Telescope Test Bed (TBT) is being developed under ESA's General Studies and Technology Programme, and shall implement a test-bed for the validation of an autonomous optical observing system in a realistic scenario, consisting of two telescopes located in Spain and Australia, to collect representative test data for precursor NEO services. It is foreseen that this test-bed environment will be used to validate future prototype software systems as well as to evaluate remote monitoring and control techniques. The test-bed system will be capable to deliver astrometric and photometric data of the observed objects in near real-time. This contribution describes the current status of the project.

Performance Evaluation of a Data Validation System

NASA Technical Reports Server (NTRS)

Wong, Edmond (Technical Monitor); Sowers, T. Shane; Santi, L. Michael; Bickford, Randall L.

2005-01-01

Online data validation is a performance-enhancing component of modern control and health management systems. It is essential that performance of the data validation system be verified prior to its use in a control and health management system. A new Data Qualification and Validation (DQV) Test-bed application was developed to provide a systematic test environment for this performance verification. The DQV Test-bed was used to evaluate a model-based data validation package known as the Data Quality Validation Studio (DQVS). DQVS was employed as the primary data validation component of a rocket engine health management (EHM) system developed under NASA's NGLT (Next Generation Launch Technology) program. In this paper, the DQVS and DQV Test-bed software applications are described, and the DQV Test-bed verification procedure for this EHM system application is presented. Test-bed results are summarized and implications for EHM system performance improvements are discussed.

A methodology for the comparative evaluation of alternative bioseparation technologies.

PubMed

Tran, Richard; Zhou, Yuhong; Lacki, Karol M; Titchener-Hooker, Nigel J

2008-01-01

Advances in upstream technologies and growing commercial demand have led to cell culture processes of ever larger volumes and expressing at higher product titers. This has increased the burden on downstream processing. Concerns regarding the capacity limitations of packed-bed chromatography have led process engineers to begin investigating new bioseparation techniques that may be considered as "alternatives" to chromatography, and which could potentially offer higher processing capacities but at a lower cost. With the wide range of alternatives, which are currently available, each with their own strengths and inherent limitations, coupled with the time pressures associated with process development, the challenge for process engineers is to determine which technologies are most worth investigating. This article presents a methodology based on a multiattribute decision making (MADM) analysis approach, utilizing both quantitative and qualitative data, which can be used to determine the "industrial attractiveness" of bioseparation technologies, accounting for trade-offs between their strengths and weaknesses. By including packed-bed chromatography in the analysis as a reference point, it was possible to determine the alternatives, which show the most promise for use in large-scale manufacturing processes. The results of this analysis show that although the majority of alternative techniques offer certain advantages over conventional packed-bed chromatography, their attractiveness overall means that currently none of these technologies may be considered as viable alternatives to chromatography. The methodology introduced in this study may be used to gain significant quantitative insight as to the key areas in which improvements are required for each technique, and thus may be used as a tool to aid in further technological development.

Experimental attrition rates of bed-material sediment from geologic provinces of Western Oregon and their application to regional sediment models

NASA Astrophysics Data System (ADS)

Mangano, J.; O'Connor, J. E.; Jones, K. L.; Wallick, R.

2011-12-01

Many topographic, hydrologic, and land use variables affect the supply and transport of bed-material in rivers, but the underlying geology is a key factor controlling both the volume of introduced material and the attrition of bed-material as it moves downstream. Recent and ongoing USGS river studies in Western Oregon document strong links between geologic province and bed-material transport. Rivers originating in the Mesozoic metamorphic and intrusive igneous rocks of the Klamath terranes of southwestern Oregon have the greatest gravel transport rates (and channel and valley-bottom morphologies reflecting high bed-material fluxes), whereas the generally lesser amounts of gravel in streams that drain Oregon's Coast Range and western Cascade Range owes in large part to Tertiary sedimentary and volcanic units underlying most of these basins. Aspects of these differences are controlled by supply as well as clast attrition. Here we aim to quantify bed-material attrition rates associated with the five main geologic provinces of Western Oregon: the Klamath terranes, Western Cascades, High Cascades, Coast Range sedimentary rocks, and Coast Range volcanic rocks. Bed-material samples were collected throughout the region from streams that drain a single geologic province and tumbled with a lapidary tumbler to determine relative attrition rates. Two kilograms of each sample were sorted into an initial distribution of clast sizes (from 16 to 64mm) and tumbled, with periodic breaks to reweigh and sieve the sample. Results show marked differences in attrition rates, with the sedimentary rocks of the Coast Range having weight loss coefficients between 1.206 and 0.211/km, orders of magnitude greater than all of the other sampled provinces. For comparison, bed material from the Klamath terranes have weight loss coefficients ranging from 0.013 to 0.005/km, and a control sample of quartzite clasts (from the Klamath terranes) has a weight loss coefficient of 0.001/km. These results confirm that bed-material attrition is an important process affecting bed-material supply and transport, and will allow for more complete development of regional bed-material sediment budgets in ongoing efforts to understand patterns of gravel abundance and channel morphology in rivers of Western Oregon.

Process Engineering Technology Center Initiative

NASA Technical Reports Server (NTRS)

Centeno, Martha A.

2001-01-01

NASA's Kennedy Space Center (KSC) is developing as a world-class Spaceport Technology Center (STC). From a process engineering (PE) perspective, the facilities used for flight hardware processing at KSC are NASA's premier factories. The products of these factories are safe, successful shuttle and expendable vehicle launches carrying state-of-the-art payloads. PE is devoted to process design, process management, and process improvement, rather than product design. PE also emphasizes the relationships of workers with systems and processes. Thus, it is difficult to speak of having a laboratory for PE at KSC because the entire facility is practically a laboratory when observed from a macro level perspective. However, it becomes necessary, at times, to show and display how KSC has benefited from PE and how KSC has contributed to the development of PE; hence, it has been proposed that a Process Engineering Technology Center (PETC) be developed to offer a place with a centralized focus on PE projects, and a place where KSC's PE capabilities can be showcased, and a venue where new Process Engineering technologies can be investigated and tested. Graphics for showcasing PE capabilities have been designed, and two initial test beds for PE technology research have been identified. Specifically, one test bed will look into the use of wearable computers with head mounted displays to deliver work instructions; the other test bed will look into developing simulation models that can be assembled into one to create a hierarchical model.

Process Engineering Technology Center Initiative

NASA Technical Reports Server (NTRS)

Centeno, Martha A.

2002-01-01

NASA's Kennedy Space Center (KSC) is developing as a world-class Spaceport Technology Center (STC). From a process engineering (PE) perspective, the facilities used for flight hardware processing at KSC are NASA's premier factories. The products of these factories are safe, successful shuttle and expendable vehicle launches carrying state-of-the-art payloads. PE is devoted to process design, process management, and process improvement, rather than product design. PE also emphasizes the relationships of workers with systems and processes. Thus, it is difficult to speak of having a laboratory for PE at K.S.C. because the entire facility is practically a laboratory when observed from a macro level perspective. However, it becomes necessary, at times, to show and display how K.S.C. has benefited from PE and how K.S.C. has contributed to the development of PE; hence, it has been proposed that a Process Engineering Technology Center (PETC) be developed to offer a place with a centralized focus on PE projects, and a place where K.S.C.'s PE capabilities can be showcased, and a venue where new Process Engineering technologies can be investigated and tested. Graphics for showcasing PE capabilities have been designed, and two initial test beds for PE technology research have been identified. Specifically, one test bed will look into the use of wearable computers with head mounted displays to deliver work instructions; the other test bed will look into developing simulation models that can be assembled into one to create a hierarchical model.

The mobility and distribution of heavy metals during the formation of first cycle red beds.

USGS Publications Warehouse

Zielinski, R.A.; Bloch, S.; Walker, T.R.

1983-01-01

Analysis of the heavy metal content in a Holocene-Pliocene red bed sequence near San Felipe in N Baja California, Mexico, has yielded new information on the mobility and distribution of these metals during ageing of iron oxyhydroxides from the amorphous to the crystalline state. Whole-rock samples (27) and a series of successive leachates were analysed for V, Al, Cr, Mn, Fe, Co, Ni, Cu and Zn by ICP spectrometry and for U by a delayed neutron technique. These data are supported by a variety of other mineralogical and petrographical observations. The results indicate that the metal content of the samples is predominantly inherited from the constituent detrital minerals. Reddening of the whole-rock samples does not promote major open-system migration of the heavy metals; rather, contained metals redistribute themselves on an intergranular scale, moving from detrital mineral hosts to the secondary iron oxides. The amount of secondary iron oxides and the fraction of whole-rock metals associated with these oxides increase during red-bed development. In addition, the abundance of well- crystallized iron oxides increases during this period. Differences in the leaching efficiency for various metals are related to differences in metal site distribution and intergranular permeability. Inferred conditions for rapid vs limited removal of metals from red beds are summarized. It is suggested that developed red beds which are well flushed by suitable pore fluids may be sources of significant quantities of heavy metals. -J.E.S.

Modeling sediment transport with an integrated view of the biofilm effects

NASA Astrophysics Data System (ADS)

Fang, H. W.; Lai, H. J.; Cheng, W.; Huang, L.; He, G. J.

2017-09-01

Most natural sediment is invariably covered by biofilms in reservoirs and lakes, which have significant influence on bed form dynamics and sediment transport, and also play a crucial role in natural river evolution, pollutant transport, and habitat changes. However, most models for sediment transport are based on experiments using clean sediments without biological materials. In this study, a three-dimensional mathematical model of hydrodynamics and sediment transport is presented with a comprehensive consideration of the biofilm effects. The changes of the bed resistance mainly due to the different bed form dynamics of the biofilm-coated sediment (biosediment), which affect the hydrodynamic characteristics, are considered. Moreover, the variations of parameters related to sediment transport after the biofilm growth are integrated, including the significant changes of the incipient velocity, settling velocity, reference concentration, and equilibrium bed load transport rate. The proposed model is applied to evaluate the effects of biofilms on the hydrodynamic characteristics and sediment transport in laboratory experiments. Results indicate that the mean velocity increases after the biofilm growth, and the turbulence intensity near the river bed decreases under the same flow condition. Meanwhile, biofilm inhibits sediment from moving independently. Thus, the moderate erosion is observed for biosediment resulting in smaller suspended sediment concentrations. The proposed model can reasonably reflect these sediment transport characteristics with biofilms, and the approach to integration of the biological impact could also be used in other modeling of sediment transport, which can be further applied to provide references for the integrated management of natural aqueous systems.

West-Antarctic Ice Streams: Analog to Ice Flow in Channels on Mars

NASA Technical Reports Server (NTRS)

Lucchitta, B. K.

1997-01-01

Sounding of the sea floor in front of the Ross Ice Shelf in Antarctica recently revealed large persistent patterns of longitudinal megaflutes and drumlinoid forms, which are interpreted to have formed at the base of ice streams during the list glacial advance. The flutes bear remarkable resemblance to longitudinal grooves and highly elongated streamlined islands found on the floors of some large martian channels, called outflow channels. ln addition, other similarities exist between Antarctic ice streams and outflow channels. Ice streams are 30 to 80 km wide and hundreds of kilometers long, as are the martian channels. Ice stream beds are below sea level. Floors of many martian outflow channels lie below martian datum, which may have been close to or below past martian sea levels. The Antarctic ice stream bed gradient is flat and locally may go uphill, and surface slopes are exceptionally low. So are gradients of martian channels. The depth to the bed in ice streams is 1 to 1.5 km. At bankful stage, the depth of the fluid in outflow channels would have been 1 to 2 km. These similarities suggest that the martian outflow channels, whose origin is commonly attributed to gigantic catastrophic floods, were locally filled by ice that left a conspicuous morphologic imprint. Unlike the West-Antarctic-ice streams, which discharge ice from an ice sheet, ice in the martian channels came from water erupting from the ground. In the cold martian environment, this water, if of moderate volume, would eventually freeze. Thus it may have formed icings on springs, ice dams and jams on constrictions in the channel path, or frozen pools. Given sufficient thickness and downhill surface gradient, these ice masses would have moved; and given the right conditions, they could have moved like Antarctic ice streams.

Move to improve: the feasibility of using an early mobility protocol to increase ambulation in the intensive and intermediate care settings.

PubMed

Drolet, Anne; DeJuilio, Patti; Harkless, Sherri; Henricks, Sherry; Kamin, Elizabeth; Leddy, Elizabeth A; Lloyd, Joanna M; Waters, Carissa; Williams, Sarah

2013-02-01

Prolonged bed rest in hospitalized patients leads to deconditioning, impaired mobility, and the potential for longer hospital stays. The purpose of this study was to determine the effectiveness of a nurse-driven mobility protocol to increase the percentage of patients ambulating during the first 72 hours of their hospital stay. A quasi-experimental design was used before and after intervention in a 16-bed adult medical/surgical intensive care unit (ICU) and a 26-bed adult intermediate care unit (IMCU) at a large community hospital. A multidisciplinary team developed and implemented a mobility order set with an embedded algorithm to guide nursing assessment of mobility potential. Based on the assessments, the protocol empowers the nurse to consult physical therapists or occupational therapists when appropriate. Daily ambulation status reports were reviewed each morning to determine each patient's activity level. Retrospective and prospective chart reviews were performed to evaluate the effectiveness of the protocol for patients 18 years of age and older who were hospitalized 72 hours or longer. In the 3 months prior to implementation of the Move to Improve project, 6.2% (12 of 193) of the ICU patients and 15.5% (54 of 349) of the IMCU patients ambulated during the first 72 hours of their hospitalization. During the 6 months following implementation, those rates rose to 20.2% (86 of 426) and 71.8% (257 of 358), respectively. The study was carried out at only one center. The initial experience with a nurse-driven mobility protocol suggests that the rate of patient ambulation in an adult ICU and IMCU during the first 72 hours of a hospital stay can be increased.

Sex that moves mountains: The influence of spawning fish on river profiles over geologic timescales

NASA Astrophysics Data System (ADS)

Fremier, Alexander K.; Yanites, Brian J.; Yager, Elowyn M.

2018-03-01

A key component of resilience is to understand feedbacks among components of biophysical systems, such as physical drivers, ecological responses and the subsequent feedbacks onto physical process. While physically based explanations of biological speciation are common (e.g., mountains separating a species can lead to speciation), less common is the inverse process examined: can a speciation event have significant influence on physical processes and patterns in a landscape? When such processes are considered, such as with 'ecosystem engineers', many studies have focused on the short-term physical and biological effects rather than the long-term impacts. Here, we formalized the physical influence of salmon spawning on stream beds into a model of channel profile evolution by altering the critical shear stress required to move stream bed particles. We then asked if spawning and an adaptive radiation event (similar to the one that occurred in Pacific salmon species) could have an effect on channel erosion processes and stream profiles over geological timescales. We found that spawning can profoundly influence the longitudinal profiles of stream beds and thereby the evolution of entire watersheds. The radiation of five Pacific salmon from a common ancestor, additionally, could also cause significant geomorphic change by altering a wider section of the profile for a given distribution of grain sizes. This modeling study suggests that biological evolution can impact landscape evolution by increasing the sediment transport and erosion efficiency of mountain streams. Moreover, the physical effects of a species on its environment might be a complementary explanation for rapid radiation events in species through the creation of new habitat types. This example provides an illustrative case for thinking about the long- and short-term coupling of biotic and abiotic systems.

Pilot-scale Limestone Emission Control (LEC) process: A development project. Volume 1, Main report and appendices A, B, C, and D: Final report

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

Prudich, M.E.; Appell, K.W.; McKenna, J.D.

ETS, Inc., a pollution consulting firm with headquarters in Roanoke, Virginia, has developed a dry, limestone-based flue gas desulfurization (FGD) system. This SO{sub 2} removal system, called Limestone Emission Control (LEC), can be designed for installation on either new or existing coal-fired boilers. In the LEC process, the SO{sub 2} in the flue gas reacts with wetted granular limestone that is contained in a moving bed. A surface layer of principally calcium sulfate (CaSO{sub 4}) is formed on the limestone. Periodic removal of this surface layer by mechanical agitation allows high utilization of the limestone granules. A nominal 5,000 acfmmore » LEC pilot plant has been designed, fabricated and installed on the slipstream of a 70,000 pph stoker boiler providing steam to Ohio University`s Athens, Ohio campus. A total of over 90 experimental trials have been performed using the pilot-scale moving-bed LEC dry scrubber as a part of this research project with run times ranging up to a high of 125 hours. SO{sub 2} removal efficiencies as high as 99.9% were achievable for all experimental conditions studied during which sufficient humidification was added to the LEC bed. The LEC process and conventional limestone scrubbing have been compared on an equatable basis using flue gas conditions that would be expected at the outlet of the electrostatic precipitator (ESP) of a 500 MW coal-fired power plant. The LEC was found to have a definite economic advantage in both direct capital costs and operating costs. Based on the success and findings of the present project, the next step in LEC process development will be a full-scale commercial demonstration unit.« less

Designing components using smartMOVE electroactive polymer technology

NASA Astrophysics Data System (ADS)

Rosenthal, Marcus; Weaber, Chris; Polyakov, Ilya; Zarrabi, Al; Gise, Peter

2008-03-01

Designing components using SmartMOVE TM electroactive polymer technology requires an understanding of the basic operation principles and the necessary design tools for integration into actuator, sensor and energy generation applications. Artificial Muscle, Inc. is collaborating with OEMs to develop customized solutions for their applications using smartMOVE. SmartMOVE is an advanced and elegant way to obtain almost any kind of movement using dielectric elastomer electroactive polymers. Integration of this technology offers the unique capability to create highly precise and customized motion for devices and systems that require actuation. Applications of SmartMOVE include linear actuators for medical, consumer and industrial applications, such as pumps, valves, optical or haptic devices. This paper will present design guidelines for selecting a smartMOVE actuator design to match the stroke, force, power, size, speed, environmental and reliability requirements for a range of applications. Power supply and controller design and selection will also be introduced. An overview of some of the most versatile configuration options will be presented with performance comparisons. A case example will include the selection, optimization, and performance overview of a smartMOVE actuator for the cell phone camera auto-focus and proportional valve applications.

Combining microwave resonance technology to multivariate data analysis as a novel PAT tool to improve process understanding in fluid bed granulation.

PubMed

Lourenço, Vera; Herdling, Thorsten; Reich, Gabriele; Menezes, José C; Lochmann, Dirk

2011-08-01

A set of 192 fluid bed granulation batches at industrial scale were in-line monitored using microwave resonance technology (MRT) to determine moisture, temperature and density of the granules. Multivariate data analysis techniques such as multiway partial least squares (PLS), multiway principal component analysis (PCA) and multivariate batch control charts were applied onto collected batch data sets. The combination of all these techniques, along with off-line particle size measurements, led to significantly increased process understanding. A seasonality effect could be put into evidence that impacted further processing through its influence on the final granule size. Moreover, it was demonstrated by means of a PLS that a relation between the particle size and the MRT measurements can be quantitatively defined, highlighting a potential ability of the MRT sensor to predict information about the final granule size. This study has contributed to improve a fluid bed granulation process, and the process knowledge obtained shows that the product quality can be built in process design, following Quality by Design (QbD) and Process Analytical Technology (PAT) principles. Copyright © 2011. Published by Elsevier B.V.

Destruction of problematic airborne contaminants by hydrogen reduction using a Catalytically Active, Regenerable Sorbent (CARS)

NASA Technical Reports Server (NTRS)

Thompson, John O.; Akse, James R.

1993-01-01

Thermally regenerable sorbent beds were demonstrated to be a highly efficient means for removal of toxic airborne trace organic contaminants aboard spacecraft. The utilization of the intrinsic weight savings available through this technology was not realized since many of the contaminants desorbed during thermal regeneration are poisons to the catalytic oxidizer or form highly toxic oxidation by-products in the Trace Contaminant Control System (TCCS). Included in this class of compounds are nitrogen, sulfur, silicon, and halogen containing organics. The catalytic reduction of these problematic contaminants using hydrogen at low temperatures (200-300 C) offers an attractive route for their destruction since the by-products of such reactions, hydrocarbons and inorganic gases, are easily removed by existing technology. In addition, the catalytic oxidizer can be operated more efficiently due to the absence of potential poisons, and any posttreatment beds can be reduced in size. The incorporation of the catalyst within the sorbent bed further improves the system's efficiency. The demonstration of this technology provides the basis for an efficient regenerable TCCS for future NASA missions and can be used in more conventional settings to efficiently remove environmental pollutants.

Apparatus and method for solar coal gasification

DOEpatents

Gregg, David W.

1980-01-01

Apparatus for using focused solar radiation to gasify coal and other carbonaceous materials. Incident solar radiation is focused from an array of heliostats onto a tower-mounted secondary mirror which redirects the focused solar radiation down through a window onto the surface of a vertically-moving bed of coal, or a fluidized bed of coal, contained within a gasification reactor. The reactor is designed to minimize contact between the window and solids in the reactor. Steam introduced into the gasification reactor reacts with the heated coal to produce gas consisting mainly of carbon monoxide and hydrogen, commonly called "synthesis gas", which can be converted to methane, methanol, gasoline, and other useful products. One of the novel features of the invention is the generation of process steam at the rear surface of the secondary mirror.

Apparatus for solar coal gasification

DOEpatents

Gregg, D.W.

Apparatus for using focused solar radiation to gasify coal and other carbonaceous materials is described. Incident solar radiation is focused from an array of heliostats onto a tower-mounted secondary mirror which redirects the focused solar radiation down through a window onto the surface of a vertically-moving bed of coal, or a fluidized bed of coal, contained within a gasification reactor. The reactor is designed to minimize contact between the window and solids in the reactor. Steam introduced into the gasification reactor reacts with the heated coal to produce gas consisting mainly of carbon monoxide and hydrogen, commonly called synthesis gas, which can be converted to methane, methanol, gasoline, and other useful products. One of the novel features of the invention is the generation of process steam at the rear surface of the secondary mirror.

Tracking channel bed resiliency in forested mountain catchments using high temporal resolution channel bed movement

NASA Astrophysics Data System (ADS)

Conklin, M. H.; Martin, S.

2017-12-01

This study uses continuous-recording load cell pressure sensors in four, high-elevation (1500-1800 m), Sierra Nevada, headwater streams, to collect high temporal resolution, bedload-movement data for investigating the channel bed movement patterns within these streams for water years 2012-2014. Data show an annual pattern where channel bed material in the thalweg starts to build up in early fall, peaks around peak snow melt, and scours back to baseline levels during hydrograph drawdown and baseflow. This pattern is punctuated by disturbance and recovery of channel bed material associated with short-term, storm events. We propose conceptual model, linking sediment sources at the channel margins to patterns of channel bed fill and scour in the thalweg, based on this and earlier work showing in-stream sources for bedload material. The material in the thalweg represents a balance between sediment supply from the channel margins and sporadic, conveyor-belt-like, downstream transport in the thalweg. The conceptual model highlights not only the importance of production and transport rates but also that seasonal connectedness between the margins and thalweg is a key sediment control, determining both the accumulation rate of sediment stores at the margins, and the redistribution of sediment from margins to thalweg that "feeds" the conveyor-belt. Disturbance and recovery cycles are observed at multiple temporal scales, but long term, the channel beds are stable, suggesting the beds act as short-term storage for sediment, but are in equilibrium interannually. The feasibility of use for these sensors in forested mountain stream environments is tested. Despite a high failure rate (50%), load cell pressure sensors show potential for high-temporal-resolution bedload measurements, allowing for the collection of channel bed movement data to move beyond time-integrated change measurements - where many of the subtleties of bedload movement patterns may be missed - to continuous and/or real-time measurements. This type of high-temporal-resolution data provides insight into short term cycles of bedload movement in high gradient, forested, mountain streams.

Tracking channel bed resiliency in forested mountain catchments using high temporal resolution channel bed movement

NASA Astrophysics Data System (ADS)

Martin, Sarah E.; Conklin, Martha H.

2018-01-01

This study uses continuous-recording load cell pressure sensors in four, high-elevation (1500-1800 m), Sierra Nevada headwater streams to collect high-temporal-resolution, bedload-movement data for investigating the channel bed movement patterns within these streams for water years 2012-2014. Data show an annual pattern where channel bed material in the thalweg starts to build up in early fall, peaks around peak snow melt, and scours back to baseline levels during hydrograph drawdown and base flow. This pattern is punctuated by disturbance and recovery of channel bed material associated with short-term storm events. A conceptual model, linking sediment sources at the channel margins to patterns of channel bed fill and scour in the thalweg, is proposed building on the results of Martin et al. (2014). The material in the thalweg represents a balance between sediment supply from the channel margins and sporadic, conveyor-belt-like downstream transport in the thalweg. The conceptual model highlights not only the importance of production and transport rates but also that seasonal connectedness between the margins and thalweg is a key sediment control, determining the accumulation rate of sediment stores at the margins and the redistribution of sediment from margins to thalweg that feeds the conveyor belt. Disturbance and recovery cycles are observed at multiple temporal scales; but long term, the channel beds are stable, suggesting that the beds act as short-term storage for sediment but are in equilibrium interannually. The feasibility of use for these sensors in forested mountain stream environments is tested. Despite a high failure rate (50%), load cell pressure sensors show potential for high-temporal-resolution bedload measurements, allowing for the collection of channel bed movement data to move beyond time-integrated change measurements - where many of the subtleties of bedload movement patterns may be missed - to continuous and/or real-time measurements. This type of high-temporal-resolution data provides insight into short-term cycles of bedload movement in high gradient, forested mountain streams.

Speckle-correlation analysis of the microcapillary blood circulation in nail bed

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

Vilenskii, M A; Agafonov, D N; Zimnyakov, D A

2011-04-30

We present the results of the experimental studies of the possibility of monitoring the blood microcirculation in human finger nail bed with application of speckle-correlation analysis, based on estimating the contrast of time-averaged dynamic speckles. The hemodynamics at normal blood circulation and under conditions of partially suppressed blood circulation is analysed. A microscopic analysis is performed to visualise the structural changes in capillaries that are caused by suppressing blood circulation. The problems and prospects of speckle-correlation monitoring of the nail bed microhemodynamics under laboratory and clinical conditions are discussed. (optical technologies in biophysics and medicine)

Upgrading of a small overloaded activated sludge plant using a MBBR system.

PubMed

Andreottola, G; Foladori, P; Gatti, G; Nardelli, P; Pettena, M; Ragazzi, M

2003-01-01

The aim of this research was the application of a biofilm system for the upgrading of a full-scale overloaded activated sludge MWWTP using the MBBR (Moving Bed Biofilm Reactor) technology. The choice of this fixed biomass system appeared appropriate because it offers several advantages including good potential in nitrification process, easiness of management and above all, the possibility to use the existing tank with very few modifications. MBBR system counts only few full-scale plants in Italy at the moment, thus a pilot-scale experimentation was preliminarily carried out. The acquired parameters were used for the fullscale MWWTP upgrading. The upgrading of the activated sludge reactor in the MBBR system has given (1) a relevant increase in the flowrate treated up to 60%; (2) a good efficiency in organic carbon removal and nitrification, equal to 88% and 90% respectively, with HRTs of 5.5-7 h; (3) the overcoming of the hydraulic overload of the secondary settler, applying a lamellar settler. It was observed a good correlation between the results obtained at pilot-scale and those observed in the full-scale plant.

Exploration Medical System Demonstration (EMSD) Project

NASA Technical Reports Server (NTRS)

Chin, Duane

2012-01-01

The Exploration Medical System Demonstration (EMSD) is a project under the Exploration Medical Capability (ExMC) element managed by the Human Research Program (HRP). The vision for the EMSD is to utilize ISS as a test bed to show that several medical technologies needed for an exploration mission and medical informatics tools for managing evidence and decision making can be integrated into a single system and used by the on-orbit crew in an efficient and meaningful manner. Objectives: a) Reduce and even possibly eliminate the time required for on-orbit crew and ground personnel (which include Surgeon, Biomedical Engineer (BME) Flight Controller, and Medical Operations Data Specialist) to access and move medical data from one application to another. b) Demonstrate that the on-orbit crew has the ability to access medical data/information using an intuitive and crew-friendly software solution to assist/aid in the treatment of a medical condition. c) Develop a common data management framework and architecture that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all crew health and life sciences activities.

The Biological Deep Sea Hydrothermal Vent as a Model to Study Carbon Dioxide Capturing Enzymes

PubMed Central

Minic, Zoran; Thongbam, Premila D.

2011-01-01

Deep sea hydrothermal vents are located along the mid-ocean ridge system, near volcanically active areas, where tectonic plates are moving away from each other. Sea water penetrates the fissures of the volcanic bed and is heated by magma. This heated sea water rises to the surface dissolving large amounts of minerals which provide a source of energy and nutrients to chemoautotrophic organisms. Although this environment is characterized by extreme conditions (high temperature, high pressure, chemical toxicity, acidic pH and absence of photosynthesis) a diversity of microorganisms and many animal species are specially adapted to this hostile environment. These organisms have developed a very efficient metabolism for the assimilation of inorganic CO2 from the external environment. In order to develop technology for the capture of carbon dioxide to reduce greenhouse gases in the atmosphere, enzymes involved in CO2 fixation and assimilation might be very useful. This review describes some current research concerning CO2 fixation and assimilation in the deep sea environment and possible biotechnological application of enzymes for carbon dioxide capture. PMID:21673885

The biological deep sea hydrothermal vent as a model to study carbon dioxide capturing enzymes.

PubMed

Minic, Zoran; Thongbam, Premila D

2011-01-01

Deep sea hydrothermal vents are located along the mid-ocean ridge system, near volcanically active areas, where tectonic plates are moving away from each other. Sea water penetrates the fissures of the volcanic bed and is heated by magma. This heated sea water rises to the surface dissolving large amounts of minerals which provide a source of energy and nutrients to chemoautotrophic organisms. Although this environment is characterized by extreme conditions (high temperature, high pressure, chemical toxicity, acidic pH and absence of photosynthesis) a diversity of microorganisms and many animal species are specially adapted to this hostile environment. These organisms have developed a very efficient metabolism for the assimilation of inorganic CO₂ from the external environment. In order to develop technology for the capture of carbon dioxide to reduce greenhouse gases in the atmosphere, enzymes involved in CO₂ fixation and assimilation might be very useful. This review describes some current research concerning CO₂ fixation and assimilation in the deep sea environment and possible biotechnological application of enzymes for carbon dioxide capture.

A New Method for Tracking Individual Particles During Bed Load Transport in a Gravel-Bed River

NASA Astrophysics Data System (ADS)

Tremblay, M.; Marquis, G. A.; Roy, A. G.; Chaire de Recherche Du Canada En Dynamique Fluviale

2010-12-01

Many particle tracers (passive or active) have been developed to study gravel movement in rivers. It remains difficult, however, to document resting and moving periods and to know how particles travel from one deposition site to another. Our new tracking method uses the Hobo Pendant G acceleration Data Logger to quantitatively describe the motion of individual particles from the initiation of movement, through the displacement and to the rest, in a natural gravel river. The Hobo measures the acceleration in three dimensions at a chosen temporal frequency. The Hobo was inserted into 11 artificial rocks. The rocks were seeded in Ruisseau Béard, a small gravel-bed river in the Yamaska drainage basin (Québec) where the hydraulics, particle sizes and bed characteristics are well known. The signals recorded during eight floods (Summer and Fall 2008-2009) allowed us to develop an algorithm which classifies the periods of rest and motion. We can differentiate two types of motion: sliding and rolling. The particles can also vibrate while remaining in the same position. The examination of the movement and vibration periods with respect to the hydraulic conditions (discharge, shear stress, stream power) showed that vibration occurred mostly before the rise of hydrograph and allowed us to establish movement threshold and response times. In all cases, particle movements occurred during floods but not always in direct response to increased bed shear stress and stream power. This method offers great potential to track individual particles and to establish a spatiotemporal sequence of the intermittent transport of the particle during a flood and to test theories concerning the resting periods of particles on a gravel bed.

40 CFR 57.102 - Eligibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., but not the cost of compliance). (i) Retrofit control technologies. (A) Sulfuric acid plant in conjunction with an adequately demonstrated replacement technology or process modification; (B) Magnesium... burning in conjunction with acid plant; (D) Electric Furnace; (E) Noranda process; (F) Fluid bed roaster...

40 CFR 57.102 - Eligibility.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., but not the cost of compliance). (i) Retrofit control technologies. (A) Sulfuric acid plant in conjunction with an adequately demonstrated replacement technology or process modification; (B) Magnesium... burning in conjunction with acid plant; (D) Electric Furnace; (E) Noranda process; (F) Fluid bed roaster...

40 CFR 57.102 - Eligibility.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., but not the cost of compliance). (i) Retrofit control technologies. (A) Sulfuric acid plant in conjunction with an adequately demonstrated replacement technology or process modification; (B) Magnesium... burning in conjunction with acid plant; (D) Electric Furnace; (E) Noranda process; (F) Fluid bed roaster...

40 CFR 57.102 - Eligibility.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., but not the cost of compliance). (i) Retrofit control technologies. (A) Sulfuric acid plant in conjunction with an adequately demonstrated replacement technology or process modification; (B) Magnesium... burning in conjunction with acid plant; (D) Electric Furnace; (E) Noranda process; (F) Fluid bed roaster...

40 CFR 57.102 - Eligibility.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., but not the cost of compliance). (i) Retrofit control technologies. (A) Sulfuric acid plant in conjunction with an adequately demonstrated replacement technology or process modification; (B) Magnesium... burning in conjunction with acid plant; (D) Electric Furnace; (E) Noranda process; (F) Fluid bed roaster...

Model-based identification of optimal operating conditions for amino acid simulated moving bed enantioseparation using a macrocyclic glycopeptide stationary phase.

PubMed

Fuereder, Markus; Majeed, Imthiyas N; Panke, Sven; Bechtold, Matthias

2014-06-13

Teicoplanin aglycone columns allow efficient separation of amino acid enantiomers in aqueous mobile phases and enable robust and predictable simulated moving bed (SMB) separation of racemic methionine despite a dependency of the adsorption behavior on the column history (memory effect). In this work we systematically investigated the influence of the mobile phase (methanol content) and temperature on SMB performance using a model-based optimization approach that accounts for methionine solubility, adsorption behavior and back pressure. Adsorption isotherms became more favorable with increasing methanol content but methionine solubility was decreased and back pressure increased. Numerical optimization suggested a moderate methanol content (25-35%) for most efficient operation. Higher temperature had a positive effect on specific productivity and desorbent requirement due to higher methionine solubility, lower back pressure and virtually invariant selectivity at high loadings of racemic methionine. However, process robustness (defined as a difference in flow rate ratios) decreased strongly with increasing temperature to the extent that any significant increase in temperature over 32°C will likely result in operating points that cannot be realized technically even with the lab-scale piston pump SMB system employed in this study. Copyright © 2014. Published by Elsevier B.V.

Kinetic energy density and agglomerate abrasion rate during blending of agglomerates into powders.

PubMed

Willemsz, Tofan A; Hooijmaijers, Ricardo; Rubingh, Carina M; Tran, Thanh N; Frijlink, Henderik W; Vromans, Herman; van der Voort Maarschalk, Kees

2012-01-23

Problems related to the blending of a cohesive powder with a free flowing bulk powder are frequently encountered in the pharmaceutical industry. The cohesive powder often forms lumps or agglomerates which are not dispersed during the mixing process and are therefore detrimental to blend uniformity. Achieving sufficient blend uniformity requires that the blending conditions are able to break up agglomerates, which is often an abrasion process. This study was based on the assumption that the abrasion rate of agglomerates determines the required blending time. It is shown that the kinetic energy density of the moving powder bed is a relevant parameter which correlates with the abrasion rate of agglomerates. However, aspects related to the strength of agglomerates should also be considered. For this reason the Stokes abrasion number (St(Abr)) has been defined. This parameter describes the ratio between the kinetic energy density of the moving powder bed and the work of fracture of the agglomerate. The St(Abr) number is shown to predict the abrasion potential of agglomerates in the dry-mixing process. It appeared possible to include effects of filler particle size and impeller rotational rate into this concept. A clear relationship between abrasion rate of agglomerates and the value of St(Abr) was demonstrated. Copyright © 2011 Elsevier B.V. All rights reserved.

Measuring and modeling the oxygen profile in a nitrifying Moving Bed Biofilm Reactor.

PubMed

Masić, Alma; Bengtsson, Jessica; Christensson, Magnus

2010-09-01

In this paper we determine the oxygen profile in a biofilm on suspended carriers in two ways: firstly by microelectrode measurements and secondly by a simple mathematical model. The Moving Bed Biofilm Reactor is well-established for wastewater treatment where bacteria grow as a biofilm on the protective surfaces of suspended carriers. The flat shaped BiofilmChip P was developed to allow good conditions for transport of substrates into the biofilm. The oxygen profile was measured in situ the nitrifying biofilm with a microelectrode and it was simulated with a one-dimensional mathematical model. We extended the model by adding a CSTR equation, to connect the reactor to the biofilm through the boundary conditions. We showed the dependence of the thickness of the mass transfer boundary layer on the bulk flow rate. Finally, we estimated the erosion parameter lambda to increase the concordance between the measured and simulated profiles. This lead to a simple empirical relationship between lambda and the flow rate. The data gathered by in situ microelectrode measurements can, together with the mathematical model, be used in predictive modeling and give more insight in the design of new carriers, with the ambition of making process operation more energy efficient. Copyright 2010 Elsevier Inc. All rights reserved.

An integrated mathematical model for chemical oxygen demand (COD) removal in moving bed biofilm reactors (MBBR) including predation and hydrolysis.

PubMed

Revilla, Marta; Galán, Berta; Viguri, Javier R

2016-07-01

An integrated mathematical model is proposed for modelling a moving bed biofilm reactor (MBBR) for removal of chemical oxygen demand (COD) under aerobic conditions. The composite model combines the following: (i) a one-dimensional biofilm model, (ii) a bulk liquid model, and (iii) biological processes in the bulk liquid and biofilm considering the interactions among autotrophic, heterotrophic and predator microorganisms. Depending on the values for the soluble biodegradable COD loading rate (SCLR), the model takes into account a) the hydrolysis of slowly biodegradable compounds in the bulk liquid, and b) the growth of predator microorganisms in the bulk liquid and in the biofilm. The integration of the model and the SCLR allows a general description of the behaviour of COD removal by the MBBR under various conditions. The model is applied for two in-series MBBR wastewater plant from an integrated cellulose and viscose production and accurately describes the experimental concentrations of COD, total suspended solids (TSS), nitrogen and phosphorous obtained during 14 months working at different SCLRs and nutrient dosages. The representation of the microorganism group distribution in the biofilm and in the bulk liquid allow for verification of the presence of predator microorganisms in the second reactor under some operational conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Organic matter degradation in a greywater recycling system using a multistage moving bed biofilm reactor (MBBR).

PubMed

Saidi, Assia; Masmoudi, Khaoula; Nolde, Erwin; El Amrani, Btissam; Amraoui, Fouad

2017-12-01

Greywater is an important non-conventional water resource which can be treated and recycled in buildings. A decentralized greywater recycling system for 223 inhabitants started operating in 2006 in Berlin, Germany. High load greywater undergoes advanced treatment in a multistage moving bed biofilm reactor (MBBR) followed by sand filtration and UV disinfection. The treated water is used safely as service water for toilet flushing. Monitoring of the organic matter degradation was pursued to describe the degradation processes in each stage and optimize the system. Results showed that organic matter reduction was achieved for the most part in the first three reactors, whereas the highest reduction rate was observed in the third reactor in terms of COD (chemical oxygen demand), dissolved organic carbon and BOD 7 (biological oxygen demand). The results also showed that the average loading rate entering the system was 3.7 kg COD/d, while the removal rate was 3.4 kg COD/d in a total bioreactor volume of 11.7 m³. In terms of BOD, the loading rate was 2.8 kg BOD/d and it was almost totally removed. This system requires little space (0.15 m²/person) and maintenance work of less than one hour per month and it shows operational stability under peak loads.

Carrier effects on tertiary nitrifying moving bed biofilm reactor: An examination of performance, biofilm and biologically produced solids.

PubMed

Forrest, Daina; Delatolla, Robert; Kennedy, Kevin

2016-01-01

Increasingly stricter ammonia and nitrogen release regulations with respect to wastewater effluents are creating a need for tertiary treatment systems. The moving bed biofilm reactor (MBBR) is being considered as an upgrade option for an increasing number of wastewater treatment facilities due to its small footprint and ease of operation. Despite the MBBRs creation as a system to remove nitrogen, recent research on MBBR systems showing that the system's performance is directly related to carrier surface area and is irrespective of carrier shape and type has been performed exclusively on chemical oxygen demand (COD) removal systems. Furthermore, the influence of carrier type on the solids produced by MBBR systems has also been exclusively studied for COD removal systems. This work investigates the effects of three specific carrier types on ammonia removal rates, biofilm morphology, along with solids production and settleability of tertiary nitrifying MBBR systems. The study concludes that carrier type has no significant effect on tertiary nitrifying MBBR system performance under steady, moderate loading conditions. The research does however highlight the propensity of greater surface area to volume carriers to become clogged under high loading conditions and that the high surface area carriers investigated in this study required longer adjustment periods to changes in loading after becoming clogged.

Start-up of membrane bioreactor and hybrid moving bed biofilm reactor-membrane bioreactor: kinetic study.

PubMed

Leyva-Díaz, J C; Poyatos, J M

2015-01-01

A hybrid moving bed biofilm reactor-membrane bioreactor (hybrid MBBR-MBR) system was studied as an alternative solution to conventional activated sludge processes and membrane bioreactors. This paper shows the results obtained from three laboratory-scale wastewater treatment plants working in parallel in the start-up and steady states. The first wastewater treatment plant was a MBR, the second one was a hybrid MBBR-MBR system containing carriers both in anoxic and aerobic zones of the bioreactor (hybrid MBBR-MBRa), and the last one was a hybrid MBBR-MBR system which contained carriers only in the aerobic zone (hybrid MBBR-MBRb). The reactors operated with a hydraulic retention time of 30.40 h. A kinetic study for characterizing heterotrophic biomass was carried out and organic matter and nutrients removals were evaluated. The heterotrophic biomass of the hybrid MBBR-MBRb showed the best kinetic performance in the steady state, with yield coefficient for heterotrophic biomass=0.30246 mg volatile suspended solids per mg chemical oxygen demand, maximum specific growth rate for heterotrophic biomass=0.00308 h(-1) and half-saturation coefficient for organic matter=3.54908 mg O2 L(-1). The removal of organic matter was supported by the kinetic study of heterotrophic biomass.

Three-Dimensional Stratification of Bacterial Biofilm Populations in a Moving Bed Biofilm Reactor for Nitritation-Anammox

PubMed Central

Almstrand, Robert; Persson, Frank; Daims, Holger; Ekenberg, Maria; Christensson, Magnus; Wilén, Britt-Marie; Sörensson, Fred; Hermansson, Malte

2014-01-01

Moving bed biofilm reactors (MBBRs) are increasingly used for nitrogen removal with nitritation-anaerobic ammonium oxidation (anammox) processes in wastewater treatment. Carriers provide protected surfaces where ammonia oxidizing bacteria (AOB) and anammox bacteria form complex biofilms. However, the knowledge about the organization of microbial communities in MBBR biofilms is sparse. We used new cryosectioning and imaging methods for fluorescence in situ hybridization (FISH) to study the structure of biofilms retrieved from carriers in a nitritation-anammox MBBR. The dimensions of the carrier compartments and the biofilm cryosections after FISH showed good correlation, indicating little disturbance of biofilm samples by the treatment. FISH showed that Nitrosomonas europaea/eutropha-related cells dominated the AOB and Candidatus Brocadia fulgida-related cells dominated the anammox guild. New carriers were initially colonized by AOB, followed by anammox bacteria proliferating in the deeper biofilm layers, probably in anaerobic microhabitats created by AOB activity. Mature biofilms showed a pronounced three-dimensional stratification where AOB dominated closer to the biofilm-water interface, whereas anammox were dominant deeper into the carrier space and towards the walls. Our results suggest that current mathematical models may be oversimplifying these three-dimensional systems and unless the multidimensionality of these systems is considered, models may result in suboptimal design of MBBR carriers. PMID:24481066

Start-up of two moving bed membrane bioreactors treating saline wastewater contaminated by hydrocarbons.

PubMed

Campo, R; Di Prima, N; Freni, G; Giustra, M G; Di Bella, G

2016-01-01

This work aims to assess the acclimation of microorganisms to a gradual increase of salinity and hydrocarbons, during the start-up of two moving bed membrane bioreactors (MB-MBRs) fed with saline oily wastewater. In both systems an ultrafiltration membrane was used and two types of carriers were employed: polyurethane sponge cubes (MB-MBRI) and polyethylene cylindrical carriers (MB-MBRII). A decreasing dilution factor of slops has been adopted in order to allow biomass acclimation. The simultaneous effect of salinity and hydrocarbons played an inhibitory role in biomass growth and this resulted in a decrease of the biological removal efficiencies. A reduction of bound extracellular polymeric substances and a simultaneous release of soluble microbial products (SMPs) were observed, particularly in the MB-MBRII system, probably due to the occurrence of a greater suspended biomass stress as response to the recalcitrance of substrate. On the one hand, a clear attachment of biomass occurred only in MB-MBRI and this affected the fouling deposition on the membrane surface. The processes of detachment and entrapment of biomass, from and into the carriers, significantly influenced the superficial cake deposition and its reversibility. On the other hand, in MB-MBRII, the higher production of SMPs implied a predominance of the pore blocking.

Decolourization of remazol black-5 textile dyes using moving bed bio-film reactor

NASA Astrophysics Data System (ADS)

Pratiwi, R.; Notodarmojo, S.; Helmy, Q.

2018-01-01

The desizing and dyeing processes in the textile industries produces wastewaster containing high concentration of organic matter and colour, so it needs treatment before released to environment. In this research, removal of azo dye (Remazol Black 5/RB 5) and organic as COD was performed using Moving Bed Biofilm Reactor (MBBR). MBBR is biological treatment process with attached growth media system that can increase removal of organic matter in textile wastewater. The effectiveness of ozonation as pre-treatment process to increase the removal efficiency in MBBR was studied. The results showed that in MBBR batch system with detention time of 1 hour, pre-treatment with ozonation prior to MBBR process able to increase the colour removal efficiency of up to 86.74%. While on the reactor without ozone pre-treatment, the colour removal efficiency of up to 68.6% was achieved. From the continuous reactor experiments found that both colour and COD removal efficiency depends on time detention of RB-5 dyes in the system. The higher of detention time, the higher of colour and COD removal efficiency. It was found that optimum removal of colour and COD was achieved in 24 hour detention time with its efficiency of 96.9% and 89.13%, respectively.

Operation Joint Endeavor in Bosnia: telemedicine systems and case reports.

PubMed

Calcagni, D E; Clyburn, C A; Tomkins, G; Gilbert, G R; Cramer, T J; Lea, R K; Ehnes, S G; Zajtchuk, R

1996-01-01

For the last several years the U.S. Department of Defense (DoD) has operated a telemedicine test bed at the U.S. Army Medical Research and Material Command's Medical Advanced Technology Management Office. The goal of this test bed is to reengineer the military health service system from the most forward deployed forces to tertiary care teaching medical centers within the United States by exploiting emerging telemedicine technologies. The test bed has conducted numerous proof-of-concept telemedicine demonstrations as part of military exercises and in support of real-world troop deployments. The most ambitious of those demonstrations is Primetime III, an ongoing effort to provide telemedicine and other advanced technology support to medical units supporting Operation Joint Endeavor in Bosnia. Several of the first instances of the clinical use of the Primetime III systems are presented as case reports in this paper. These reports demonstrate capabilities and limitations of telemedicine. The Primetime III system demonstrates the technical ability to provide current telecommunications capabilities to medical units stationed in the remote, austere, difficult-to-serve environment of Bosnia. Telemedicine capabilities cannot be used without adequate training, operations, and sustainment support. Video consultations have eliminated the need for some evacuations. The system has successfully augmented the clinical capability of physicians assigned to these medical units. Fullest clinical utilization of telemedicine technologies requires adjustment of conventional clinical practice patterns.

Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

NASA Technical Reports Server (NTRS)

Button, Amy B.; Sweterlitsch, Jeffrey J.; Cox, Marlon R.

2010-01-01

An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In three previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology. That testing was performed in a sea-level pressure environment with both simulated and real human metabolic loads, and in both open and closed-loop configurations. The Orion ARS is designed to also support space-suited operations in a depressurized cabin, so the next step in developmental testing at JSC was to test the ARS technology in a typical closed space suit-loop environment with low-pressure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure, high-oxygen, closed-loop testing of the Orion ARS technology, and it was conducted with simulated human metabolic loads in March 2009. The test investigated pressure drops and flow balancing through two different styles of prototype suit umbilical connectors. General swing-bed performance was tested with both umbilical configurations, as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable suit atmospheric CO2 and moisture levels.

Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

NASA Technical Reports Server (NTRS)

Lin, Amy; Sweterlitsch, Jeffrey; Cox, Marlon

2009-01-01

An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology in a sea-level pressure environment with simulated human metabolic loads. Another paper at this year s conference discusses similar testing with real human metabolic loads, including some closed-loop testing with emergency breathing masks. The Orion ARS is designed to also support extravehicular activity operations from a depressurized cabin. The next step in developmental testing at JSC was, therefore, to test this ARS technology in a typical closed space suit loop environment with low-pressure pure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure oxygen loop testing of a new Orion ARS technology, and was conducted with simulated human metabolic loads in December 2008. The test investigated pressure drops through two different styles of prototype suit umbilical connectors and general swing-bed performance with both umbilical configurations as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable atmospheric CO2 and moisture levels.

The Effect of Computer Games on the Proficiency of the B.Ed. Teacher Trainees in Using the Conventional Expressions in Conversations

ERIC Educational Resources Information Center

Muthiah, Rajendran

2015-01-01

The purpose of the study is to assess the effect of computer games on the proficiency of the B.Ed teacher trainees in using the conventional expressions in conversations. The role of technology in language learning has made outdated, drills, grammatical explanations and translation of texts, and the focus is shifted to communication based…

Possible change in distribution of seaweed, Sargassum horneri, in northeast Asia under A2 scenario of global warming and consequent effect on some fish.

PubMed

Komatsu, Teruhisa; Fukuda, Masahiro; Mikami, Atsuko; Mizuno, Shizuha; Kantachumpoo, Attachai; Tanoue, Hideaki; Kawamiya, Michio

2014-08-30

Global warming effects on seaweed beds are already perceptible. Their geographical distributions greatly depend on water temperatures. To predict future geographical distributions of brown alga, Sargassum horneri, forming large beds in the northwestern Pacific, we referred to future monthly surface water temperatures at about 1.1° of longitude and 0.6° of latitude in February and August in 2050 and 2100 simulated by 12 organizations under an A2 scenario of global warming. The southern limit of S. horneri distribution is expected to keep moving northward such that it may broadly disappear from Honshu Island, the Chinese coast, and Korean Peninsula in 2100, when tropical Sargassum species such as Sargassum tenuifolium may not completely replace S. horneri. Thus, their forests in 2100 do not substitute those of S. horneri in 2000. Fishes using the beds and seaweed rafts consisting of S. horneri in East China Sea suffer these disappearances. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Postural responses of head and foot cutaneous microvascular flow and their sensitivity to bed rest

NASA Technical Reports Server (NTRS)

Aratow, Michael; Hargens, Alan R.; Meyer, J.-UWE; Arnaud, Sara B.

1991-01-01

To explore the mechanism for facial puffiness, headache, and nasal congestion associated with microgravity and cephalad fluid shifts, the postural responses of the cutaneous microcirculation (CMC) in the forehead and dorsum of the foot of eight healthy men were studied by changing body position on a tilt table and measuring blood flows with a laser Doppler flowmeter. Increasing arterial pressure in the feet by moving from a -6-deg head-down tilt to a 60-deg head-up posture decreased foot CMC by 46.5 + or - 12.0 percent. Raising arterial pressure in the head increased forehead CMC by 25.5 + or - 0.7 percent (p less than 0.05). To investigate the possibility that these opposite responses could be modified by simulated microgravity, tilt test were repeated after 7 d of -6-deg head-down-tilt bed rest. The responses were not significantly different from those recorded before bed rest. Therefore, CMC in the feet is well regulated to prevent edema when shifting to an upright position, whereas there is less regulation in the head CMC.

Laboratory evaluation of an OTT acoustic digital current meter and a SonTek Laboratory acoustic Doppler velocimeter

USGS Publications Warehouse

Vermeyen, T.B.; Oberg, Kevin A.; Jackson, Patrick Ryan

2009-01-01

Recently, an acoustic current meter known as the OTT * acoustic digital current meter (ADC) was introduced as an alternative instrument for stream gaging measurements. The Bureau of Reclamation and the U.S. Geological Survey collaborated on a side- by-side evaluation of the ADC and a SonTek/YSI acoustic Doppler velocimeter (ADV). Measurements were carried out in a laboratory flume to evaluate the performance characteristics of the ADC under a range of flow and boundary conditions. The flume contained a physical model of a mountain river with a diversion dam and variety of bed materials ranging from smooth mortar to a cobble bed. The instruments were installed on a trolley system that allowed them to be easily moved within the flume while maintaining a consistent probe orientation. More than 50 comparison measurements were made in an effort to verify the manufacturer’s performance specifications and to evaluate potential boundary disturbance for near-bed and vertical boundary measurements. Data and results from this evaluation are presented and discussed. 

Selective phenol methylation to 2,6-dimethylphenol in a fluidized bed of iron-chromium mixed oxide catalyst with o-cresol circulation.

PubMed

Zukowski, Witold; Berkowicz, Gabriela; Baron, Jerzy; Kandefer, Stanisław; Jamanek, Dariusz; Szarlik, Stefan; Wielgosz, Zbigniew; Zielecka, Maria

2014-01-01

2,6-dimethylphenol (2,6-DMP) is a product of phenol methylation, especially important for the plastics industry. The process of phenol methylation in the gas phase is strongly exothermic. In order to ensure good temperature equalization in the catalyst bed, the process was carried out using a catalyst in the form of a fluidized bed - in particular, the commercial iron-chromium catalyst TZC-3/1. Synthesis of 2,6-dimethylphenol from phenol and methanol in fluidized bed of iron-chromium catalyst was carried out and the fluidization of the catalyst was examined. Stable state of fluidized bed of iron-chromium catalyst was achieved. The measured velocities allowed to determine the minimum flow of reactants, ensuring introduction of the catalyst bed in the reactor into the state of fluidization. Due to a high content of o-cresol in products of 2,6-dimethylphenol synthesis, circulation in the technological node was proposed. A series of syntheses with variable amount of o-cresol in the feedstock allowed to determine the parameters of stationary states. A stable work of technological node with o-cresol circulation is possible in the temperature range of350-380°C, and o-cresolin/phenolin molar ratio of more than 0.48. Synthesis of 2,6-DMP over the iron-chromium catalyst is characterized by more than 90% degree of phenol conversion. Moreover, the O-alkylation did not occur (which was confirmed by GC-MS analysis). By applying o-cresol circulation in the 2,6-DMP process, selectivity of more than 85% degree of 2,6-DMP was achieved. The participation levels of by-products: 2,4-DMP and 2,4,6-TMP were low. In the optimal conditions based on the highest yield of 2,6-DMP achieved in the technological node applying o-cresol circulation, there are 2%mol. of 2,4-DMP and 6%mol. of 2,4,6-TMP in the final mixture, whereas 2,4,6-TMP can be useful as a chain stopper and polymer's molar mass regulator during the polymerization of 2,6-DMP.

Computational open-channel hydraulics for movable-bed problems

USGS Publications Warehouse

Lai, Chintu; ,

1990-01-01

As a major branch of computational hydraulics, notable advances have been made in numerical modeling of unsteady open-channel flow since the beginning of the computer age. According to the broader definition and scope of 'computational hydraulics,' the basic concepts and technology of modeling unsteady open-channel flow have been systematically studied previously. As a natural extension, computational open-channel hydraulics for movable-bed problems are addressed in this paper. The introduction of the multimode method of characteristics (MMOC) has made the modeling of this class of unsteady flows both practical and effective. New modeling techniques are developed, thereby shedding light on several aspects of computational hydraulics. Some special features of movable-bed channel-flow simulation are discussed here in the same order as given by the author in the fixed-bed case.

Assessment of UASB-DHS technology for sewage treatment: a comparative study from a sustainability perspective.

PubMed

Maharjan, Namita; Nomoto, Naoki; Tagawa, Tadashi; Okubo, Tsutomu; Uemura, Shigeki; Khalil, Nadeem; Hatamoto, Masashi; Yamaguchi, Takashi; Harada, Hideki

2018-04-06

This paper assesses the technical and economic sustainability of a combined system of an up-flow anaerobic sludge blanket (UASB)-down-flow hanging sponge (DHS) for sewage treatment. Additionally, this study compares UASB-DHS with current technologies in India like trickling filters (TF), sequencing batch reactor (SBR), moving bed biofilm reactor (MBBR), and other combinations of UASB with post-treatment systems such as final polishing ponds (FPU) and extended aeration sludge process (EASP). The sustainability of the sewage treatment plants (STPs) was evaluated using a composite indicator, which incorporated environmental, societal, and economic dimensions. In case of the individual sustainability indicator study, the results showed that UASB-FPU was the most economically sustainable system with a score of 0.512 and aeration systems such as MBBR, EASP, and SBR were environmentally sustainable, whereas UASB-DHS system was socially sustainable. However, the overall comparative analysis indicated that the UASB-DHS system scored the highest value of 2.619 on the global sustainability indicator followed by EASP and MBBR with scores of 2.322 and 2.279, respectively. The highlight of this study was that the most environmentally sustainable treatment plants were not economically and socially sustainable. Moreover, sensitivity analysis showed that five out of the seven scenarios tested, the UASB-DHS system showed good results amongst the treatment system.

JPL control/structure interaction test bed real-time control computer architecture

NASA Technical Reports Server (NTRS)

Briggs, Hugh C.

1989-01-01

The Control/Structure Interaction Program is a technology development program for spacecraft that exhibit interactions between the control system and structural dynamics. The program objectives include development and verification of new design concepts - such as active structure - and new tools - such as combined structure and control optimization algorithm - and their verification in ground and possibly flight test. A focus mission spacecraft was designed based upon a space interferometer and is the basis for design of the ground test article. The ground test bed objectives include verification of the spacecraft design concepts, the active structure elements and certain design tools such as the new combined structures and controls optimization tool. In anticipation of CSI technology flight experiments, the test bed control electronics must emulate the computation capacity and control architectures of space qualifiable systems as well as the command and control networks that will be used to connect investigators with the flight experiment hardware. The Test Bed facility electronics were functionally partitioned into three units: a laboratory data acquisition system for structural parameter identification and performance verification; an experiment supervisory computer to oversee the experiment, monitor the environmental parameters and perform data logging; and a multilevel real-time control computing system. The design of the Test Bed electronics is presented along with hardware and software component descriptions. The system should break new ground in experimental control electronics and is of interest to anyone working in the verification of control concepts for large structures.

Advanced Turbine Technology Applications Project (ATTAP)

NASA Technical Reports Server (NTRS)

1992-01-01

ATTAP activities during the past year included test-bed engine design and development, ceramic component design, materials and component characterization, ceramic component process development and fabrication, ceramic component rig testing, and test-bed engine fabrication and testing. Significant technical challenges remain, but all areas exhibited progress. Test-bed engine design and development included engine mechanical design, combustion system design, alternate aerodynamic designs of gasifier scrolls, and engine system integration aimed at upgrading the AGT-5 from a 1038 C (1900 F) metal engine to a durable 1372 C (2500 F) structural ceramic component test-bed engine. ATTAP-defined ceramic and associated ceramic/metal component design activities completed include the ceramic gasifier turbine static structure, the ceramic gasifier turbine rotor, ceramic combustors, the ceramic regenerator disk, the ceramic power turbine rotors, and the ceramic/metal power turbine static structure. The material and component characterization efforts included the testing and evaluation of seven candidate materials and three development components. Ceramic component process development and fabrication proceeded for the gasifier turbine rotor, gasifier turbine scroll, gasifier turbine vanes and vane platform, extruded regenerator disks, and thermal insulation. Component rig activities included the development of both rigs and the necessary test procedures, and conduct of rig testing of the ceramic components and assemblies. Test-bed engine fabrication, testing, and development supported improvements in ceramic component technology that permit the achievement of both program performance and durability goals. Total test time in 1991 amounted to 847 hours, of which 128 hours were engine testing, and 719 were hot rig testing.

Reproductive Potential of Salmon Spawning Substrates Inferred from Grain Size and Fish Length

NASA Astrophysics Data System (ADS)

Riebe, C. S.; Sklar, L. S.; Overstreet, B. T.; Wooster, J. K.; Bellugi, D. G.

2014-12-01

The river restoration industry spends millions of dollars every year on improving salmon spawning in riverbeds where sediment is too big for fish to move and thus use during redd building. However, few studies have addressed the question of how big is too big in salmon spawning substrates. Hence managers have had little quantitative basis for gauging the amount of spawning habitat in coarse-bedded rivers. Moreover, the scientific framework has remained weak for restoration projects that seek to improve spawning conditions. To overcome these limitations, we developed a physically based, field-calibrated model for the fraction of the bed that is fine-grained enough to support spawning by fish of a given size. Model inputs are fish length and easy-to-measure indices of bed-surface grain size. Model outputs include the number of redds and eggs the substrate can accommodate when flow depth, temperature, and other environmental factors are not limiting. The mechanistic framework of the model captures the biophysical limits on sediment movement and the space limitations on redd building and egg deposition in riverbeds. We explored the parameter space of the model and found a previously unrecognized tradeoff in salmon size: bigger fish can move larger sediment and thus use more riverbed area for spawning; they also tend to have higher fecundity, and so can deposit more eggs per redd; however, because redd area increases with fish length, the number of eggs a substrate can accommodate is highest for moderate-sized fish. One implication of this tradeoff is that differences in grain size may help regulate river-to-river differences in salmon size. Thus, our model suggests that population diversity and, by extension, species resilience are linked to lithologic, geomorphic, and climatic factors that determine grain size in rivers. We cast the model into easy-to-use look-up tables, charts, and computer applications, including a JavaScript app that works on tablets and mobile phones. We explain how these tools can be used in a new, mechanistic approach to assessing spawning substrates and optimizing gravel augmentation projects in coarse-bedded rivers.

Modeling wood dynamics, jam formation, and sediment storage in a gravel-bed stream

NASA Astrophysics Data System (ADS)

Eaton, B. C.; Hassan, M. A.; Davidson, S. L.

2012-12-01

In small and intermediate sized streams, the interaction between wood and bed material transport often determines the nature of the physical habitat, which in turn influences the health of the stream's ecosystem. We present a stochastic model that can be used to simulate the effects on physical habitat of forest fires, climate change, and other environmental disturbances that alter wood recruitment. The model predicts large wood (LW) loads in a stream as well as the volume of sediment stored by the wood; while it is parameterized to describe gravel bed streams similar to a well-studied field prototype, Fishtrap Creek, British Columbia, it can be calibrated to other systems as well. In the model, LW pieces are produced and modified over time as a result of random tree-fall, LW breakage, LW movement, and piece interaction to form LW jams. Each LW piece traps a portion of the annual bed material transport entering the reach and releases the stored sediment when the LW piece is entrained and moved. The equations governing sediment storage are based on a set of flume experiments also scaled to the field prototype. The model predicts wood loads ranging from 70 m3/ha to more than 300 m3/ha, with a mean value of 178 m3/ha: both the range and the mean value are consistent with field data from streams with similar riparian forest types and climate. The model also predicts an LW jam spacing that is consistent with field data. Furthermore, our modeling results demonstrate that the high spatial and temporal variability in sediment storage, sediment transport, and channel morphology associated with LW-dominated streams occurs only when LW pieces interact and form jams. Model runs that do not include jam formation are much less variable. These results suggest that river restoration efforts using engineered LW pieces that are fixed in place and not permitted to interact will be less successful at restoring the geomorphic processes responsible for producing diverse, productive physical habitats than efforts using LW pieces that are free to move, interact, and form LW jams.

Controlling thermal properties of dense gas fluidized beds for concentrated solar power by internal and external solids circulation

NASA Astrophysics Data System (ADS)

Ammendola, Paola; Bareschino, Piero; Chirone, Riccardo; Salatino, Piero; Solimene, Roberto

2017-06-01

Fluidization technology displays a long record of success stories, mostly related to applications to thermal and thermochemical processes, which are fostering extension to novel and relatively unexplored fields. Application of fluidized beds to collection and thermal storage of solar radiation in Concentrated Solar Power (CSP) is one of the most promising, a field which poses challenging issues and great opportunities to fluidization scientists and technologists. The potential of this growing field calls for reconsideration of some of the typical design and operation guidelines and criteria, with the goal of exploiting the inherently good thermal performances of gas-fluidized beds at their best. "Creative" and non-conventional design and operation of fluidized beds, like those based on internal and external solids circulation, may be beneficial to the enhancement of thermal diffusivity and surface-to-bed heat transfer, improving the potential for application in the very demanding context of CSP with thermal energy storage. This paper investigated: i) a fluidized bed configuration with an uneven distribution of the fluidizing gas to promote vortices in the scale of bed height (internal solids circulation); ii) a dual fluidized bed configuration characterized by an external solids circulation achieved by the operation of a riser and a bubbling fluidized bed. CFD simulations showed the hydrodynamics conditions under which the internal solids circulation was established. The hydrodynamic characterization of the external solids circulation was achieved by an experimental study carried out with different cold models. The dual fluidized bed system was optimized in terms of operating conditions and geometrical features of the connections between two fluidized beds.

Adaptive Structures Programs for the Strategic Defense Initiative Organization

DTIC Science & Technology

1992-01-01

Advanced Control Technology Experiment ( ACTEX ) Modular Control Patch High Frequency Passive Damping Strut Development Optional PZT Passive...on this space test bed in FY95. The Advanced Control Technology Experiment ( ACTEX ) will demonstrate many of the adaptive structures technologies...Accelerometer Bi-ax Accelerometer Smart Strut Figure 7. Schematic of Advanced Control Technology Experiment ( ACTEX ) 6-28-91-2M 1-6-92-5M PZ Stack

The Sleep and Technology Use of Americans: Findings from the National Sleep Foundation's 2011 Sleep in America Poll

PubMed Central

Gradisar, Michael; Wolfson, Amy R.; Harvey, Allison G.; Hale, Lauren; Rosenberg, Russell; Czeisler, Charles A.

2013-01-01

Study Objectives: To describe the technology use and sleep quality of Americans, and the unique association between technology use and sleep disturbances. Methods: Interviews were conducted via random digit dialing (N = 750) or the Internet (N = 758). 1,508 Americans (13-64 years old, 50% males) matched to 2009 U.S. Census data provided complete interviews. The sample was further divided into adolescents (13-18 years, N = 171), young adults (19-29 years, N = 293), middle-aged adults (30-45 years, N = 469), and older adults (46-64 years, N = 565) to contrast different generations' technology use. Participants answered a 47-item semi-structured survey, including questions about their sleep habits, and the presence and use of technology in the hour before bed in the past 2 weeks. Results: Nine of 10 Americans reported using a technological device in the hour before bed (e.g., TVs the most popular; 60%). However, those under 30 years of age were more likely to use cell phones (72% of adolescents, 67% of young adults) than those over 30 years (36% of middle-aged, and 16% of older adults). Young adults' sleep patterns were significantly later than other age groups on both weekdays and weekend nights. Unlike passive technological devices (e.g., TV, mp3 music players), the more interactive technological devices (i.e., computers/laptops, cell phones, video game consoles) used in the hour before bed, the more likely difficulties falling asleep (β = 9.4, p < 0.0001) and unrefreshing sleep (β = 6.4, p < 0.04) were reported. Conclusions: Technology use near bedtime is extremely prevalent in the United States. Among a range of technologies, interactive technological devices are most strongly associated with sleep complaints. Commentary: A commentary on this article appears in this issue on page 1301. Citation: Gradisar M; Wolfson AR; Harvey AG; Hale L; Rosenberg R; Czeisler CA. The sleep and technology use of Americans: findings from the National Sleep Foundation's 2011 Sleep in America Poll. J Clin Sleep Med 2013;9(12):1291-1299. PMID:24340291

Characterization of solid fuels at pressurized fluidized bed gasification conditions

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

Zevenhoven, R.; Hupa, M.

1998-07-01

The gasification of co-gasification of solid fuel (coal, peat, wood) in air-blown fluidized bed gasifiers is receiving continued attention as an alternative to entrained flow gasifiers which in general are oxygen-blown. Fluidized bed gasification of wood and wood-waste at elevated pressures, and the so-called air-blown gasification cycle are examples of processes which are under development in Europe. based on complete or partial gasification of a solid fuel in a pressurized fluidized bed. At the same time, fuel characterization data for the combination of temperature, pressure and fuel particle heating rate that is encountered in fluidized bed gasification are very scarce.more » In this paper, quantitative data on the characterization of fuels for advanced combustion and gasification technologies based on fluidized beds are given, as a result from the authors participation in the JOULE 2 extension project on clean coal technology of the European community. Eleven solid fuels, ranging from coal via peat to wood, have been studied under typical fluidized bed gasification conditions: 800--1,000 C, 1--25 bar, fuel heating rate in the order of 100--1,000 C/s. Carbon dioxide was used as gasifying agent. A pressurized thermogravimetric reactor was used for the experiments. The results show that the solid residue yield after pyrolysis/devolatilization increases with pressure and decreases with temperature. For coal, the gasification reactivity of the char increases by a factor of 3 to 4 when pressurizing from 1 to 25 bar, for the younger fuels such as peat and wood, this effect is negligible. Several empirical engineering equations are given which relate the fuel performance to the process parameters and the proximate and chemical analyses of the fuel. A pressure maximum was found at which a maximum gasification reactivity occurs, for practically all fuels, and depending on temperature. It is shown that this can be explained and modeled using a Langmuir-Hinshelwood model.« less

Characterisation of solid fuels at pressurised fluidised bed gasification conditions

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

Zebenhoven, R.; Hupa, M.

1998-04-01

The gasification or co-gasification of solid fuels (coal, peat, wood) in air-blown fluidised bed gasifiers is receiving continued attention as an alternative to entrained flow gasifiers which in general are oxygen-blown. Fluidised bed gasification of wood and wood-waste at elevated pressures, and the so-called air-blown gasification cycle are examples of processes which are under development in Europe, based on complete or partial gasification of a solid fuel in a pressurised fluidised bed. At the same time, fuel characterisation data for the combination of temperature, pressure and fuel particle heating rate that is encountered in fluidised bed gasification are very scarce.more » Quantitative data on the characterisation of fuels for advanced combustion and gasification technologies based on fluidised beds are given, as a result from our participation to the JOULE 2 extension project on clean coal technology of the European Community. Eleven solid fuels, ranging from coal via peat to wood, have been studied under typical fluidised bed gasification conditions: 800-1000{degrees}C, 1-25 bar, fuel heating rate in the order of 100-1000{degrees}C/s. Carbon dioxide was used as gasifying agent. A pressurised thermogravimetric reactor was used for the experiments. The results show that the solid residue yield after pyrolysis/devolatilisation. increases with pressure and decreases with temperature. For coal, the gasification reactivity of the char increases by a factor of 3 to 4 when pressurising from 1 to 25 bar, for the `younger` fuels such as peat and wood, this effect is negligible. Several empirical, `engineering` equations are given which relate the fuel performance to the process parameters and the proximate and chemical analyses of the fuel. A pressure maximum was found at which a maximum gasification reactivity occurs, for practically all fuels, and depending on temperature. It is shown that this can be explained and modelled using a Langmuir-Hinshelwood model.« less

International Space Station (ISS)

NASA Image and Video Library

1994-07-20

An artist's conception of what the final configuration of the International Space Station (ISS) will look like when it is fully built and deployed. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experimentation.

Grain velocity of bedload movement in an armored non-uniform mobile bed

NASA Astrophysics Data System (ADS)

Liu, C.

2015-12-01

The velocity of bedload particles, which directly reflects the interaction between flow and sediment, is one of the important parameters to predict sediment transport rate, is also one of the fundamental problems for sediment transport. Many excellent works have been accomplished in this filed. However, the existing researches are mostly based on the artificial fixed bed, few moveable bed studies are focus on uniform sediment bed, these boundary conditions are different from a real river. In this research, an experiment on non-uniform sediment with an armored, moveable bed were carried out in a flume, the range of bed material is from 0.2mm to 20mm. With a special hanging glass and illumination system, the motion particles in the bed were clearly shoot on top of the flume by a video camera, avoiding the interference of waves at the flow surface. The speed of the camera is 50 frames per second. About 7000 unique coordinates of moving particles were determined from 3000 frames of successive pictures, the particle velocity of longitudinal and crosswise directions were obtained from the coordinates. The results show that, the probability density distribution of grain velocities of both directions are similar to that in the uniform sediment, which have an exponent decay trend, whereas the value of cross velocity of particles is clearly greater than that in the uniform sediment condition. Negative particle velocity was recognized in the experiment, it is shown that these negative may occur at two conditions, one is the backflow of fine particles behind the coarser particles, and the other is a state of movement change, such as a particle from static state to motion or vice versa. Furthermore, the particle movement was strongly affected by the arrangement of local coarse particles. The influence of coarser particles to the movement of fine particles also identified by two opposite effects, one is the acceleration effects in a 'tunnel' between pair of series particles, the other is the deceleration effects out of the tunnel, or fine particles captured by the backwater flow just behind a coarse particle. In addition, ensemble particle velocity in the armored bed is distinctly less than which in the fixed bed and uniform bed condition with same particle Reynolds number and Shields parameter. (Supported by(2012BAB04B01;NSFC(11472310))

Expected hazards and hospital beds in host cities of the 2014 FIFA World Cup in Brazil.

PubMed

Miranda, Elaine Silva; Shoaf, Kimberley; Silva, Raulino Sabino da; Freitas, Carolina Figueiredo; Osorio-de-Castro, Claudia Garcia Serpa

2017-06-12

Planning for mass gatherings involves health system preparedness based on an understanding of natural and technological hazards identified through prior risk assessment. We present the expected hazards reported by health administrators of the host cities for the 2014 FIFA World Cup in Brazil and discuss the hazards considering minimal available public hospital beds in the 12 cities at the time of the event. Four different groups of respondents were interviewed: pharmaceutical service administrators and overall health administrators at both the municipal and hospital levels. The hospital bed occupancy rate was calculated, based on the Brazilian Health Informatics Department (DATASUS). The number of surplus beds was calculated using parameters from the literature regarding surge and mass casualty needs and number of unoccupied beds. In all groups, physical injuries ranked first, followed by emerging and endemic diseases. Baseline occupancy rates were high (95%CI: 0.93-2.19) in all 12 cities. Total shortage, considering all the cities, ranged from -47,670 (for surges) to -60,569 beds (for mass casualties). The study can contribute to discussions on mass-gathering preparedness.

HESTIA Phase I Test Results: The Air Revitalization System

NASA Technical Reports Server (NTRS)

Wright, Sarah E.; Hansen, Scott W.

2016-01-01

In any human spaceflight mission, a number of Environmental Control & Life Support System (ECLSS) technologies work together to provide the conditions astronauts need to live healthily, productively, and comfortably in space. In a long-duration mission, many of these ECLSS technologies may use materials supplied by In-Situ Resource Utilization (ISRU), introducing more interactions between systems. The Human Exploration Spacecraft Test-bed for Integration & Advancement (HESTIA) Project aims to create a test-bed to evaluate ECLSS and ISRU technologies and how they interact in a high-fidelity, closed-loop, human-rated analog habitat. Air purity and conditioning are essential components within any ECLSS and for HESTIA's first test they were achieved with the Air Revitalization System (ARS) described below. The ARS provided four essential functions to the test-bed chamber: cooling the air, removing humidity from the air, removing trace contaminants, and scrubbing carbon dioxide (CO2) from the air. In this case, the oxygen supply function was provided by ISRU. In the current configuration, the ARS is a collection of different subsystems. A fan circulates the air, while a condensing heat exchanger (CHX) pulls humidity out of the air. A Trace Contaminant Removal System (TCRS) filters the air of potentially harmful contaminants. Lastly, a Reactive Plastic Lithium Hydroxide (RP-LiOH) unit removes CO2 from the breathing air. During the HESTIA Phase I test in September 2015, the ARS and its individual components each functioned as expected, although further analysis is underway. During the Phase I testing and in prior bench-top tests, the energy balance of heat removed by the CHX was not equal to the cooling it received. This indicated possible instrument error and therefore recalibration of the instruments and follow-up testing is planned in 2016 to address the issue. The ARS was tested in conjunction with two other systems: the Human Metabolic Simulator (HMS) and the Electrolyzer. They behaved as anticipated as well. The HMS added humidity, CO2, and heat to the chamber while removing oxygen, and the Electrolyzer (an ISRU technology) added oxygen. The objective for HESTIA in 2015 was achieved: the creation of a high-fidelity test-bed for ECLSS and ISRU technologies. With the 'backbone' technologies installed, more technologies will be added to increase the analog habitat's fidelity over the next few years. The ARS was designed with this in mind, and as new technologies develop and mature, the strategic installation of the existing components will allow for them to be replaced with the new technologies.

Run-of-River Impoundments Can Remain Unfilled While Transporting Gravel Bedload: Numerical Modeling Results

NASA Astrophysics Data System (ADS)

Pearson, A.; Pizzuto, J. E.

2015-12-01

Previous work at run-of-river (ROR) dams in northern Delaware has shown that bedload supplied to ROR impoundments can be transported over the dam when impoundments remain unfilled. Transport is facilitated by high levels of sand in the impoundment that lowers the critical shear stresses for particle entrainment, and an inversely sloping sediment ramp connecting the impoundment bed (where the water depth is typically equal to the dam height) with the top of the dam (Pearson and Pizzuto, in press). We demonstrate with one-dimensional bed material transport modeling that bed material can move through impoundments and that equilibrium transport (i.e., a balance between supply to and export from the impoundment, with a constant bed elevation) is possible even when the bed elevation is below the top of the dam. Based on our field work and previous HEC-RAS modeling, we assess bed material transport capacity at the base of the sediment ramp (and ignore detailed processes carrying sediment up and ramp and over the dam). The hydraulics at the base of the ramp are computed using a weir equation, providing estimates of water depth, velocity, and friction, based on the discharge and sediment grain size distribution of the impoundment. Bedload transport rates are computed using the Wilcock-Crowe equation, and changes in the impoundment's bed elevation are determined by sediment continuity. Our results indicate that impoundments pass the gravel supplied from upstream with deep pools when gravel supply rate is low, gravel grain sizes are relatively small, sand supply is high, and discharge is high. Conversely, impoundments will tend to fill their pools when gravel supply rate is high, gravel grain sizes are relatively large, sand supply is low, and discharge is low. The rate of bedload supplied to an impoundment is the primary control on how fast equilibrium transport is reached, with discharge having almost no influence on the timing of equilibrium.

Data summary of municipal solid waste management alternatives. Volume 12, Numerically indexed bibliography

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

None

1992-10-01

This appendix contains the numerically indexed bibliography for the complete group of reports on municipal solid waste management alternatives. The list references information on the following topics: mass burn technologies, RDF technologies, fluidized bed combustion, pyrolysis and gasification of MSW, materials recovery- recycling technologies, sanitary landfills, composting and anaerobic digestion of MSW.

Data summary of municipal solid waste management alternatives. Volume 11, Alphabetically indexed bibliography

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

None

1992-10-01

This appendix contains the alphabetically indexed bibliography for the complete group of reports on municipal waste management alternatives. The references are listed for each of the following topics: mass burn technologies, RDF technologies, fluidized-bed combustion, pyrolysis and gasification of MSW, materials recovery- recycling technologies, sanitary landfills, composting, and anaerobic digestion of MSW.

COMMERCIALIZATION OF AN ATMOSPHERIC IRON-BASED CDCL PROCESS FOR POWER PRODUCTION. PHASE I: TECHNOECONOMIC ANALYSIS

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

Vargas, Luis

Coal Direct Chemical Looping (CDCL) is an advanced oxy-combustion technology that has potential to enable substantial reductions in the cost and energy penalty associated with carbon dioxide (CO2) capture from coal-fired power plants. Through collaborative efforts, the Babcock & Wilcox Power Generation Group (B&W) and The Ohio State University (OSU) developed a conceptual design for a 550 MWe (net) supercritical CDCL power plant with greater than 90% CO2 capture and compression. Process simulations were completed to enable an initial assessment of its technical performance. A cost estimate was developed following DOE’s guidelines as outlined in NETL’s report “Quality Guidelines formore » Energy System Studies: Cost Estimation Methodology for NETL Assessments of Power Plant Performance”, (2011/1455). The cost of electricity for the CDCL plant without CO2 Transportation and Storage cost resulted in $ $102.67 per MWh, which corresponds to a 26.8 % increase in cost of electricity (COE) when compared to an air-fired pulverized-coal supercritical power plant. The cost of electricity is strongly depending on the total plant cost and cost of the oxygen carrier particles. The CDCL process could capture further potential savings by increasing the performance of the particles and reducing the plant size. During the techno-economic analysis, the team identified technology and engineering gaps that need to be closed to bring the technology to commercialization. The technology gaps were focused in five critical areas: (i) moving bed reducer reactor, (ii) fluidized bed combustor, (iii) particle riser, (iv) oxygen-carrier particle properties, and (v) process operation. The key technology gaps are related to particle performance, particle manufacturing cost, and the operation of the reducer reactor. These technology gaps are to be addressed during Phase II of project. The project team is proposing additional lab testing to be completed on the particle and a 3MWth pilot facility be built to evaluate the reducer reactor performance among other aspects of the technology. A Phase II proposal was prepared and submitted to DOE. The project team proposed a three year program in Phase II. Year 1 includes lab testing and particle development work aimed at improving the chemical and mechanical properties of the oxygen carrier particle. In parallel, B&W will design the 3MWt pilot plant. Any improvements to the particle performance discovered in year 1 that would impact the design of the pilot will be incorporated into the final design. Year 2 will focus on procurement of materials and equipment, and construction of the pilot plant. Year 3 will include, commissioning, start-up, and testing in the pilot. Phase I work was successfully completed and a design and operating philosophy for a 550 MWe commercial scale coal-direct chemical looping power plant was developed. Based on the results of the techno-economic evaluation, B&W projects that the CDCL process can achieve 96.5% CO2 capture with a« less

Integration of silver nanoparticle-impregnated polyelectrolyte multilayers into murine splinted cutaneous wound beds

PubMed Central

Guthrie, Kathleen M.; Agarwal, Ankit; Teixeira, Leandro B. C.; Dubielzig, Richard R.; Abbott, Nicholas L.; Murphy, Christopher J.; Singh, Harpreet; McAnulty, Jonathan F.; Schurr, Michael J.

2013-01-01

Silver is a commonly used topical antimicrobial. However, technologies to immobilize silver at the wound surface are lacking, while currently available silver-containing wound dressings release excess silver that can be cytotoxic and impair wound healing. We have shown that precise concentrations of silver at lower levels can be immobilized into a wound bed using a polyelectrolyte multilayer (PEM) attachment technology. These silver nanoparticle-impregnated PEMs are non-cytotoxic yet bactericidal in vitro, but their effect on wound healing in vivo was previously unknown. Objective The purpose of this study was to determine the effect on wound healing of integrating silver nanoparticle/PEMs into the wound bed. Methods A full-thickness, splinted, excisional murine wound healing model was employed in both phenotypically normal mice and spontaneously diabetic mice (healing impaired model). Results Gross image measurements showed an initial small lag in healing in the silver-treated wounds in diabetic mice, but no difference in time to complete wound closure in either normal or diabetic mice. Histological analysis showed modest differences between silver-treated and control groups on day 9, but no difference between groups at the time of wound closure. Conclusions We conclude that silver nanoparticle/PEMs can be safely integrated into the wound beds of both normal and diabetic mice without delaying wound closure, and with transient histological effects. The results of this study suggest the feasibility of this technology for use as a platform to effect nanoscale wound engineering approaches to microbial prophylaxis or to augment wound healing. PMID:23511285

Advanced Turbine Technology Applications Project (ATTAP)

NASA Technical Reports Server (NTRS)

1990-01-01

Advanced Turbine Technology Application Project (ATTAP) activities during the past year were highlighted by test-bed engine design and development activities; ceramic component design; materials and component characterization; ceramic component process development and fabrication; component rig testing; and test-bed engine fabrication and testing. Although substantial technical challenges remain, all areas exhibited progress. Test-bed engine design and development activity included engine mechanical design, power turbine flow-path design and mechanical layout, and engine system integration aimed at upgrading the AGT-5 from a 1038 C metal engine to a durable 1371 C structural ceramic component test-bed engine. ATTAP-defined ceramic and associated ceramic/metal component design activities include: the ceramic combustor body, the ceramic gasifier turbine static structure, the ceramic gasifier turbine rotor, the ceramic/metal power turbine static structure, and the ceramic power turbine rotors. The materials and component characterization efforts included the testing and evaluation of several candidate ceramic materials and components being developed for use in the ATTAP. Ceramic component process development and fabrication activities are being conducted for the gasifier turbine rotor, gasifier turbine vanes, gasifier turbine scroll, extruded regenerator disks, and thermal insulation. Component rig testing activities include the development of the necessary test procedures and conduction of rig testing of the ceramic components and assemblies. Four-hundred hours of hot gasifier rig test time were accumulated with turbine inlet temperatures exceeding 1204 C at 100 percent design gasifier speed. A total of 348.6 test hours were achieved on a single ceramic rotor without failure and a second ceramic rotor was retired in engine-ready condition at 364.9 test hours. Test-bed engine fabrication, testing, and development supported improvements in ceramic component technology that will permit the achievement of program performance and durability goals. The designated durability engine accumulated 359.3 hour of test time, 226.9 of which were on the General Motors gas turbine durability schedule.

Development of the Packed Bed Reactor ISS Flight Experiment

NASA Technical Reports Server (NTRS)

Patton, Martin O.; Bruzas, Anthony E.; Rame, Enrique; Motil, Brian J.

2012-01-01

Packed bed reactors are compact, require minimum power and maintenance to operate, and are highly reliable. These features make this technology a leading candidate as a potential unit operation in support of long duration human space exploration. On earth, this type of reactor accounts for approximately 80% of all the reactors used in the chemical process industry today. Development of this technology for space exploration is truly crosscutting with many other potential applications (e.g., in-situ chemical processing of planetary materials and transport of nutrients through soil). NASA is developing an ISS experiment to address this technology with particular focus on water reclamation and air revitalization. Earlier research and development efforts funded by NASA have resulted in two hydrodynamic models which require validation with appropriate instrumentation in an extended microgravity environment. The first model developed by Motil et al., (2003) is based on a modified Ergun equation. This model was demonstrated at moderate gas and liquid flow rates, but extension to the lower flow rates expected in many advanced life support systems must be validated. The other model, developed by Guo et al., (2004) is based on Darcy s (1856) law for two-phase flow. This model has been validated for a narrow range of flow parameters indirectly (without full instrumentation) and included test points where the flow was not fully developed. The flight experiment presented will be designed with removable test sections to test the hydrodynamic models. The experiment will provide flexibility to test additional beds with different types of packing in the future. One initial test bed is based on the VRA (Volatile Removal Assembly), a packed bed reactor currently on ISS whose behavior in micro-gravity is not fully understood. Improving the performance of this system through an accurate model will increase our ability to purify water in the space environment.

Innovations in coating technology.

PubMed

Behzadi, Sharareh S; Toegel, Stefan; Viernstein, Helmut

2008-01-01

Despite representing one of the oldest pharmaceutical techniques, coating of dosage forms is still frequently used in pharmaceutical manufacturing. The aims of coating range from simply masking the taste or odour of drugs to the sophisticated controlling of site and rate of drug release. The high expectations for different coating technologies have required great efforts regarding the development of reproducible and controllable production processes. Basically, improvements in coating methods have focused on particle movement, spraying systems, and air and energy transport. Thereby, homogeneous distribution of coating material and increased drying efficiency should be accomplished in order to achieve high end product quality. Moreover, given the claim of the FDA to design the end product quality already during the manufacturing process (Quality by Design), the development of analytical methods for the analysis, management and control of coating processes has attracted special attention during recent years. The present review focuses on recent patents claiming improvements in pharmaceutical coating technology and intends to first familiarize the reader with the available procedures and to subsequently explain the application of different analytical tools. Aiming to structure this comprehensive field, coating technologies are primarily divided into pan and fluidized bed coating methods. Regarding pan coating procedures, pans rotating around inclined, horizontal and vertical axes are reviewed separately. On the other hand, fluidized bed technologies are subdivided into those involving fluidized and spouted beds. Then, continuous processing techniques and improvements in spraying systems are discussed in dedicated chapters. Finally, currently used analytical methods for the understanding and management of coating processes are reviewed in detail in the last section of the review.

Space station trace contaminant control

NASA Technical Reports Server (NTRS)

Olcutt, T.

1985-01-01

Different systems for the control of space station trace contaminants are outlined. The issues discussed include: spacecabin contaminant sources, technology base, contaminant control system elements and configuration, approach to contaminant control, contaminant load model definition, spacecraft maximum allowable concentrations, charcoal bed sizing and performance characteristics, catalytic oxidizer sizing and performance characteristics, special sorbent bed sizing, animal and plant research payload problems, and emergency upset contaminant removal. It is concluded that the trace contaminant control technology base is firm, the necessary hardware tools are available, and the previous design philosophy is still applicable. Some concerns are the need as opposed to danger of the catalytic oxidizer, contaminants with very low allowable concentrations, and the impact of relaxing materials requirements.

Impact of implementing an Internal Bed Regulation Committee on administrative and care indicators at a teaching hospital.

PubMed

Rodrigues, Luciane Cristine Ribeiro; Juliani, Carmen Maria Casquel Monti

2015-01-01

To compare hospital indicators before and after implementing an Internal Bed Regulation Committee at a reference hospital. It is an quantitative, evaluation, exploratory, descriptive and cross-sectional research. The data was gathered from the hospital administrative reports for the period 2008-2013, provided by the Information Technology Center of the Complexo FAMEMA. The indicators improved after implementation of the Internal Bed Regulation Committee. The individuals involved in the process acknowledged the improvement. It is necessary to carry on the regulatory actions, especially in a comprehensive and complex healthcare system, such as the brazilian Sistema Único de Saúde.

Defense | NREL

Science.gov Websites

Maritime Academy training ships to test promising energy saving technologies and increase steaming days between refuelings. The Maritime Pre-Screening Assessment of Conservation Technologies (M-PACT) project uses a ship-board test-bed with sophisticated sensors and a calibrated model to evaluate new and

River channel bars and dunes - Theory of kinematic waves

USGS Publications Warehouse

Langbein, Walter Basil; Leopold, Luna Bergere

1968-01-01

A kinematic wave is a grouping cf moving objects in zones along a flow path and through which the objects pass. These concentrations may be characterized by a simple relation between the speed of the moving objects and their spacing as a result of interaction between them.Vehicular traffic has long been known to have such properties. Data are introduced to show that beads carried by flowing water in a narrow flume behave in an analogous way. The flux or transport of objects in a single lane of traffic is greatest when the objects are spaced about two diameters apart; beads in a single-lane flume as well as highway traffic conform to this property.By considering the sand in a pipe or flume to a depth affected by dune movement, it is shown that flux-concentration curves similar to the previously known cases can be constructed from experimental data. From the kinematic point of view, concentration of particles in dunes and other wave bed forms results when particles in transport become more numerous or closely spaced and interact to reduce the effectiveness of the ambient water to move them.Field observations over a 5-year period are reported in which individual rocks were painted for identification and placed at various spacings on the bed of ephemeral stream in New Mexico, to study the effect of storm flows on rock movement. The data on about 14,000 rocks so observed show the effect of variable spacing which is quantitatively as well as qualitatively comparable to the spacing effect on small glass beads in a flume. Dunes and gravel bars may be considered kinematic waves caused by particle interaction, and certain of their properties can be related to the characteristics of the flux-concentration curve.

Field Assessment of Acoustic-Doppler Based Discharge Measurements

USGS Publications Warehouse

Mueller, D.S.; ,

2002-01-01

The use of equipment based on the Doppler principle for measuring water velocity and computing discharge is common within the U.S. Geological Survey (USGS). The instruments and software have changed appreciably during the last 5 years; therefore, the USGS has begun a field validation of the instruments currently (2002) available for making discharge measurements from a moving boat in streams of various sizes. Instruments manufactured by SonTek/YSI2 and RD Instruments, Inc. were used to collect discharge data at five different sites. One or more traditional discharge measurements were made by the use of a Price AA current meter and standard USGS procedures with the acoustic instruments at each site during data collection. The discharges measured with the acoustic instruments were compared with the discharges measured with Price AA meters and the current USGS stage-discharge rating for each site. The mean discharges measured by each acoustic instrument were within 5 percent of the Price AA-based measurement and (or) discharge from the stage-discharge rating. Additional analysis of the data collected indicates that the coefficient of variation of the discharge measurements consistently was less for the RD Instruments, Inc. Rio Grandes than it was for the SonTek/YSI RiverSurveyors. The bottom-tracking referenced measurement had a lower coefficient of variation than the differentially corrected global positioning system referenced measurements. It was observed that the higher frequency RiverSurveyors measured a moving bed more often than the lower frequency Rio Grandes. The detection of a moving bed caused RiverSurveyors to be consistently biased low when referenced to bottom tracking. Differentially corrected global positioning system data may be used to remove the bias observed in the bottom-tracking referenced measurements.

Hypo-Fractionated Conformal Radiation Therapy to the Tumor Bed after Segmental Mastectomy

DTIC Science & Technology

2007-07-01

reatment (17). Prone positioning of the patient rapidly •-merged as the best technique, because it minimizes move- neni of the target breast tissue...treatment ohase and 46 completed treatment. Three patients were lost to follow-up before initiating any treat- neni . and 1 patient discontinued treatment...Dossibility of completing the course of postsegmental nasiectomv radiotherapy (RT) in a smaller number of treat- nenis within a shorter Deriod is very

Li/sub 2/O microsphere fabrication. Monthly letter progress report No. 1 for the period ending May 31, 1977

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

Schluderberg, D C

1977-06-01

The purpose of this task is to establish process parameters for the fabrication of lithium oxide (Li/sub 2/O) microspheres having properties which as closely as possible approximate those required for the design characteristics of the University of Wisconsin design for a TOKAMAK-type fusion reactor utilizing the moving bed of Li/sub 2/O microspheres as both reactor coolant and tritium breeder.

Bed site selection by a subordinate predator: an example with the cougar (Puma concolor) in the Greater Yellowstone Ecosystem.

PubMed

Kusler, Anna; Elbroch, L Mark; Quigley, Howard; Grigione, Melissa

2017-01-01

As technology has improved, our ability to study cryptic animal behavior has increased. Bed site selection is one such example. Among prey species, bed site selection provides thermoregulatory benefits and mitigates predation risk, and may directly influence survival. We conducted research to test whether a subordinate carnivore also selected beds with similar characteristics in an ecosystem supporting a multi-species guild of competing predators. We employed a model comparison approach in which we tested whether cougar ( Puma concolor ) bed site attributes supported the thermoregulatory versus the predator avoidance hypotheses, or exhibited characteristics supporting both hypotheses. Between 2012-2016, we investigated 599 cougar bed sites in the Greater Yellowstone Ecosystem and examined attributes at two scales: the landscape (second-order, n  = 599) and the microsite (fourth order, n  = 140). At the landscape scale, cougars selected bed sites in winter that supported both the thermoregulatory and predator avoidance hypotheses: bed sites were on steeper slopes but at lower elevations, closer to the forest edge, away from sagebrush and meadow habitat types, and on southern, eastern, and western-facing slopes. In the summer, bed attributes supported the predator avoidance hypothesis over the thermoregulation hypothesis: beds were closer to forest edges, away from sagebrush and meadow habitat classes, and on steeper slopes. At the microsite scale, cougar bed attributes in both the winter and summer supported both the predator avoidance and thermoregulatory hypotheses: they selected bed sites with high canopy cover, high vegetative concealment, and in a rugged habitat class characterized by cliff bands and talus fields. We found that just like prey species, a subordinate predator selected bed sites that facilitated both thermoregulatory and anti-predator functions. In conclusion, we believe that measuring bed site attributes may provide a novel means of measuring the use of refugia by subordinate predators, and ultimately provide new insights into the habitat requirements and energetics of subordinate carnivores.

Integrated System Health Management (ISHM) Technology Demonstration Project Final Report

NASA Technical Reports Server (NTRS)

Mackey, Ryan; Iverson, David; Pisanich, Greg; Toberman, Mike; Hicks, Ken

2006-01-01

Integrated System Health Management (ISHM) is an essential capability that will be required to enable upcoming explorations mission systems such as the Crew Exploration Vehicle (CEV) and Crew Launch Vehicle (CLV), as well as NASA aeronautics missions. However, the lack of flight experience and available test platforms have held back the infusion by NASA Ames Research Center (ARC) and the Jet Propulsion Laboratory (JPL) of ISHM technologies into future space and aeronautical missions. To address this problem, a pioneer project was conceived to use a high-performance aircraft as a low-cost proxy to develop, mature, and verify the effectiveness of candidate ISHM technologies. Given the similarities between spacecraft and aircraft, an F/A-18 currently stationed at Dryden Flight Research Center (DFRC) was chosen as a suitable host platform for the test bed. This report describes how the test bed was conceived, how the technologies were integrated on to the aircraft, and how these technologies were matured during the project. It also describes the lessons learned during the project and a forward path for continued work.

Bed-Deformation Experiments Beneath a Temperate Glacier

NASA Astrophysics Data System (ADS)

Iverson, N. R.; Hooyer, T. S.; Fischer, U. H.; Cohen, D.; Jackson, M.; Moore, P. L.; Lappegard, G.; Kohler, J.

2002-12-01

Fast flow of glaciers and genesis of glacial landforms are commonly attributed to shear deformation of subglacial sediment. Although models of this process abound, data gathered subglacially on the kinematics and mechanics of such deformation are difficult to interpret. Major difficulties stem from the necessity of either measuring deformation near glacier margins, where conditions may be abnormal, or at the bottoms of boreholes, where the scope of instrumentation is limited, drilling disturbs sediment, and local boundary conditions are poorly known. A different approach is possible at the Svartisen Subglacial Laboratory, where tunnels melted in the ice provide temporary human access to the bed of Engabreen, a temperate outlet glacier of the Svartisen Ice Cap in Norway. A trough (2 m x 1.5 m x 0.5 m deep) was blasted in the rock bed, where the glacier is 220 m thick and sliding at 0.1-0.2 m/d. During two spring field seasons, this trough was filled with 2.5 tons of simulated till. Instruments in the till recorded shear (tiltmeters), volume change, total normal stress, and pore-water pressure as ice moved across the till surface. Pore pressure was brought to near the total normal stress by feeding water to the base of the till with a high-pressure pump, operated in a rock tunnel 4 m below the bed surface. Results illustrate some fundamental aspects of bed deformation. Permanent shear deformation requires low effective normal stress and hence high pore-water pressure, owing to the frictional nature of till. Shear strain generally increases upward in the bed toward the glacier sole, consistent with previous measurements beneath thinner ice at glacier margins. At low effective normal stresses, ice sometimes decouples from underlying till. Overall, bed deformation accounts for 10-35 % of basal motion, although this range excludes shear in the uppermost 0.05 m of till where shear was not measured. Pump tests with durations ranging from seconds to hours highlight the need to consider both elastic and permanent strain in evaluating tiltmeter records of bed kinematics.

Magnetic fabric of sheared till: A strain indicator for evaluating the bed deformation model of glacier flow

USGS Publications Warehouse

Hooyer, T.S.; Iverson, N.R.; Lagroix, F.; Thomason, J.F.

2008-01-01

Wet-based portions of ice sheets may move primarily by shearing their till beds, resting in high sediment fluxes and the development of subglacial landforms. This model of glacier movement, which requires high bed shear strains, can be tested using till microstructural characteristics that evolve during till deformation. Here we examine the development of magnetic fabric using a ring shear device to defom two Wisconsin-age basal tills to shear strains as high as 70. Hysteresis experiments and the dependence of magnetic susceptibility of these tills on temperature demonstrate that anisotropy of magnetic susceptibility (AMS) develops during shear due to the rotation of primarily magnetite particles that are silt sized or smaller. At moderate shear strains (???6-25), principal axes of maximum magnetic susceptibility develop a strong fabric (S1 eignevalues of 0.83-0.96), without further strengthening at higher strains, During deformation, directions of maximum susceptibility cluster strongly in the direction of shear and plunge 'up-glacier,' consistent with the behavior of pebbles and sand particles studied in earlier experiments. In contrast, the magnitude of AMS does not vary systematically with strain and is small relative to its variability among samples; this is because most magnetite grains are contained as inclusions in larger particles and hence do not align during shear. Although processes other than pervasive bed deformation may result in strong flow parallel fabrics, AMS fabrics provide a rapid and objective means of identifying basal tills that have not been sheared sufficiently to be compatible with the bed deformation model. Copyright 2008 by the American Geophysical Union.

Human Support Technology Research to Enable Exploration

NASA Technical Reports Server (NTRS)

Joshi, Jitendra

2003-01-01

Contents include the following: Advanced life support. System integration, modeling, and analysis. Progressive capabilities. Water processing. Air revitalization systems. Why advanced CO2 removal technology? Solid waste resource recovery systems: lyophilization. ISRU technologies for Mars life support. Atmospheric resources of Mars. N2 consumable/make-up for Mars life. Integrated test beds. Monitoring and controlling the environment. Ground-based commercial technology. Optimizing size vs capability. Water recovery systems. Flight verification topics.

Research Technology

NASA Image and Video Library

2004-04-15

Pictured is an artist's concept of the Rocket Based Combined Cycle (RBCC) launch. The RBCC's overall objective is to provide a technology test bed to investigate critical technologies associated with opperational usage of these engines. The program will focus on near term technologies that can be leveraged to ultimately serve as the near term basis for Two Stage to Orbit (TSTO) air breathing propulsions systems and ultimately a Single Stage To Orbit (SSTO) air breathing propulsion system.

Secure and Resilient Cloud Computing for the Department of Defense

DTIC Science & Technology

2015-07-21

that addresses that threat model, and (3) integrate the technology into a usable, secure, resilient cloud test bed. Underpinning this work is the...risks for the DoD’s acquisition of secure, resilient cloud technology by providing proofs of concept, technology maturity, integration demonstrations...we need a strategy for integrating LLSRC technology with the cloud services and applications that need to be secured. The LLSRC integration

Microbial Community Profiles in Wastewaters from Onsite Wastewater Treatment Systems Technology

PubMed Central

Jałowiecki, Łukasz; Chojniak, Joanna Małgorzata; Dorgeloh, Elmar; Hegedusova, Berta; Ejhed, Helene; Magnér, Jörgen; Płaza, Grażyna Anna

2016-01-01

The aim of the study was to determine the potential of community-level physiological profiles (CLPPs) methodology as an assay for characterization of the metabolic diversity of wastewater samples and to link the metabolic diversity patterns to efficiency of select onsite biological wastewater facilities. Metabolic fingerprints obtained from the selected samples were used to understand functional diversity implied by the carbon substrate shifts. Three different biological facilities of onsite wastewater treatment were evaluated: fixed bed reactor (technology A), trickling filter/biofilter system (technology B), and aerated filter system (the fluidized bed reactor, technology C). High similarities of the microbial community functional structures were found among the samples from the three onsite wastewater treatment plants (WWTPs), as shown by the diversity indices. Principal components analysis (PCA) showed that the diversity and CLPPs of microbial communities depended on the working efficiency of the wastewater treatment technologies. This study provided an overall picture of microbial community functional structures of investigated samples in WWTPs and discerned the linkages between microbial communities and technologies of onsite WWTPs used. The results obtained confirmed that metabolic profiles could be used to monitor treatment processes as valuable biological indicators of onsite wastewater treatment technologies efficiency. This is the first step toward understanding relations of technology types with microbial community patterns in raw and treated wastewaters. PMID:26807728

Influence of in line monitored fluid bed granulation process parameters on the stability of Ethinylestradiol.

PubMed

Roßteuscher-Carl, Katrin; Fricke, Sabine; Hacker, Michael C; Schulz-Siegmund, Michaela

2015-12-30

Ethinylestradiol (EE) as a highly active and low dosed compound is prone to oxidative degradation. The stability of the drug substance is therefore a critical parameter that has to be considered during drug formulation. Beside the stability of the drug substance, granule particle size and moisture are critical quality attributes (CQA) of the fluid bed granulation process which influence the tableting ability of the resulting granules. Both CQA should therefore be monitored during the production process by process analytic technology (PAT) according to ICH Q8. This work focusses on the effects of drying conditions on the stability of EE in a fluid-bed granulation process. We quantified EE degradation products 6-alpha-hydroxy-EE, 6-beta-hydroxy-EE, 9(11)-dehydro-EE and 6-oxo-EE during long time storage and accelerated conditions. PAT-tools that monitor granule particle size (Spatial filtering technology) and granule moisture (Microwave resonance technology) were applied and compared with off-line methods. We found a relevant influence of residual granule moisture and thermic stress applied during granulation on the storage stability of EE, whereas no degradation was found immediately after processing. Hence we conclude that drying parameters have a relevant influence on long term EE stability. Copyright © 2015 Elsevier B.V. All rights reserved.

Low-Impact Flooring: Does It Reduce Fall-Related Injuries?

PubMed

Hanger, H Carl

2017-07-01

To compare fall rates and injuries from falls on low-impact flooring (LIF) compared with a standard vinyl flooring. Prospective, observational, nonrandomized controlled study. Subacute Older Persons Health ward (N = 20 beds). Older inpatients. Three different types of LIF. All falls in the ward were prospectively monitored using incident reporting, noting location and consequences of each fall. Fall rates (per 1000 bed days) and injuries, were compared between bedroom falls on LIF against those occurring on standard vinyl flooring (controls). Over 31 months, there were 278 bedroom falls (from 178 fallers). The bedroom fall rate (falls per 1000 bed days occupied) did not differ between the LIF and control groups (median 15 [IQR 8-18] versus 17 [IQR 9-23], respectively; P = .47). However, fall-related injuries were significantly less frequent when they occurred on LIFs (22% of falls versus 34% of falls on control flooring; P = .02). Fractures occurred in 0.7% of falls in the LIF cohort versus 2.3% in the control cohort. Rolling resistance when moving heavier equipment, such as beds or hoists, was an issue for staff on LIF. LIF significantly reduced fall-related injuries compared with a standard vinyl flooring, whereas they did not alter the overall risk of falling. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.