30 CFR 250.1625 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2012 CFR

2012-07-01

... drills. 250.1625 Section 250.1625 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... Operations § 250.1625 Blowout preventer system testing, records, and drills. (a) Prior to conducting high..., upper and lower kelly cocks, and drill-string safety valves shall be pressure tested to pipe-ram test...

30 CFR 250.1625 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2013 CFR

2013-07-01

... drills. 250.1625 Section 250.1625 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... Operations § 250.1625 Blowout preventer system testing, records, and drills. (a) Prior to conducting high..., upper and lower kelly cocks, and drill-string safety valves shall be pressure tested to pipe-ram test...

30 CFR 250.516 - Blowout preventer system tests, inspections, and maintenance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Well-Completion Operations § 250.516 Blowout preventer system tests, inspections, and maintenance. (a...) Test affected BOP components following the disconnection or repair of any well-pressure containment... you have well-control problems. You must conduct the required BOP test as soon as possible (i.e...

30 CFR 250.1625 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 250.1625 Blowout preventer system testing, records, and drills. (a) Prior to conducting high-pressure tests, all BOP systems shall be tested to a pressure of 200 to 300 psi. (b) Ram-type BOP's and the choke manifold shall be pressure tested with water to a rated working pressure or as otherwise approved by the...

30 CFR 250.616 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.616 Blowout preventer system testing, records, and drills. (a) BOP pressure tests. When you pressure test the BOP system you must conduct a low-pressure test and a high-pressure test for each...

30 CFR 250.1707 - What are the requirements for blowout preventer system testing, records, and drills?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What are the requirements for blowout preventer system testing, records, and drills? 250.1707 Section 250.1707 Mineral Resources BUREAU OF SAFETY AND..., you must conduct a low-pressure test and a high-pressure test for each component. You must conduct the...

30 CFR 250.1707 - What are the requirements for blowout preventer system testing, records, and drills?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What are the requirements for blowout preventer system testing, records, and drills? 250.1707 Section 250.1707 Mineral Resources BUREAU OF SAFETY AND..., you must conduct a low-pressure test and a high-pressure test for each component. You must conduct the...

Windflow circulation patterns in a coastal dune blowout, south coast of Lake Michigan

USGS Publications Warehouse

Fraser, G.S.; Bennett, S.W.; Olyphant, G.A.; Bauch, N.J.; Ferguson, V.; Gellasch, C.A.; Millard, C.L.; Mueller, B.; O'Malley, P. J.; Way, J.N.; Woodfield, M.C.

1998-01-01

The windflow patterns in a large active blowout in a coastal dune on the southern shore of Lake Michigan were intensively monitored during a two-day period when the predominant winds shifted from onshore (Day 1) to offshore (Day 2). The wind data were used in conjunction with mapped geomorphic features and sedimentologic characteristics to infer the following aspects of blowout evolution: (1) Prevailing winds are transformed considerably once they enter the blowout. Flow separation occurs when offshore winds enter the blowout over the steep back wall. Separated flows may, in turn, induce countercurrent flows within the trough. Flow expansion and deceleration occur when onshore winds enter over gently sloping walls at the front of the blowout. (2) Maximum erosion occurs along the deflationary floor near the entrance to the blowout, and lateral extensional lobes are also expanding the blowout to the east. Sand avalanches down the eastern and western lateral walls toward the deflationary floor where it is moved toward the rear of the blowout and up the ramp at the south end. Sand leaves the blowout as a series of depositional lobes prograding out onto the surface of the host dune along the south and east walls. (3) Vegetation prevents expansion of the blowout in certain directions and impediments to flow, such as slump blocks, alter circulation patterns and sand transport paths. (4) Prevailing onshore winds deflate the floor and promote eastward expansion of lateral erosional lobes, whereas strong flows from the southwest apparently are the main cause of transport up the transportational ramp and over the south wall of the blowout.

Computer simulation of reservoir depletion and oil flow from the Macondo well following the Deepwater Horizon blowout

USGS Publications Warehouse

Hsieh, Paul

2010-01-01

This report describes the application of a computer model to simulate reservoir depletion and oil flow from the Macondo well following the Deepwater Horizon blowout. Reservoir and fluid data used for model development are based on (1) information released in BP's investigation report of the incident, (2) information provided by BP personnel during meetings in Houston, Texas, and (3) calibration by history matching to shut-in pressures measured in the capping stack during the Well Integrity Test. The model is able to closely match the measured shut-in pressures. In the simulation of the 86-day period from the blowout to shut in, the simulated reservoir pressure at the well face declines from the initial reservoir pressure of 11,850 pounds per square inch (psi) to 9,400 psi. After shut in, the simulated reservoir pressure recovers to a final value of 10,300 psi. The pressure does not recover back to the initial pressure owing to reservoir depletion caused by 86 days of oil discharge. The simulated oil flow rate declines from 63,600 stock tank barrels per day just after the Deepwater Horizon blowout to 52,600 stock tank barrels per day just prior to shut in. The simulated total volume of oil discharged is 4.92 million stock tank barrels. The overall uncertainty in the simulated flow rates and total volume of oil discharged is estimated to be + or - 10 percent.

Momentum kill procedure can quickly control blowouts

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

Watson, W.D.; Moore, P.

1993-08-30

The momentum kill method can help in quickly regaining control of a blowing well, providing the blowing well rate and fluid properties can be estimated reasonably. The momentum of the kill fluid counteracts and overcomes the flowing momentum of formation fluids. In other words, sufficient mud density pumped at a sufficient rate is directed into the flow stream to force the escaping fluid column back into the well bore. Sufficient kill fluid hydrostatic pressure must be stacked'' in the hole so that the well remains dead after the operation. The momentum kill is not a panacea for all blowouts. Anmore » assessment must be made of the potential problems unique to this method, and certain requirements must be met if the technique is to be successful. The paper discusses some of the considerations for evaluating the use of the momentum kill method.« less

Determination of the contaminated area after the blowouts in Alasehir (Manisa/Turkey) Geothermal Area using geophysical methods

NASA Astrophysics Data System (ADS)

Timur, Emre

2013-04-01

Western Turkey is one of the most spectacular regions of widespread active continental extension in the world. The most prominent structures of this region are E-W trending Gediz and Büyük Menderes Grabens. Geothermal activity around city of Manisa in Gediz Graben has been investigated by many researchers and many drillings has been opened in order to produce electricity and heating purposes. In the middle of May, 2012, a geothermal blowout occurred 150 m away from the deep drilling, at the depth of 1100 m, in Alkan village of Alasehir resort in city of Manisa. After that, 5 big blowouts happened at the same area and hot water had been diverted to Alkan stream for almost 4 months. In this study, it was intended to determine contaminated area by using magnetic susceptibility measurements for the surface and VLF-R method for underground layers. Magnetic observations were carried out by using Bartington MS2E system and VLF-R by Scintrex ENVI-VLF. It is observed that magnetic susceptibility values vary between 90-160 cgs in the center of the blowout and 30-80 cgs 50 m around of it. All of the susceptibility values were mapped and contaminated areas was clearly defined on the surface using 246 data points. Besides, VLF-R studies were carried out along 21 profiles each of a length of 170 m at three different frequencies with a line and station spacing of 5 m. Laterally constrained two layer inversion was applied to each station and in addition to the inversion of all profiles for each frequency, all lines were stacked within a precise resistivity interval and 2-D maps of the contaminated zones were obtained.

Characterization of Combustion Dynamics, Detection, and Prevention of an Unstable Combustion State Based on a Complex-Network Theory

NASA Astrophysics Data System (ADS)

Gotoda, Hiroshi; Kinugawa, Hikaru; Tsujimoto, Ryosuke; Domen, Shohei; Okuno, Yuta

2017-04-01

Complex-network theory has attracted considerable attention for nearly a decade, and it enables us to encompass our understanding of nonlinear dynamics in complex systems in a wide range of fields, including applied physics and mechanical, chemical, and electrical engineering. We conduct an experimental study using a pragmatic online detection methodology based on complex-network theory to prevent a limiting unstable state such as blowout in a confined turbulent combustion system. This study introduces a modified version of the natural visibility algorithm based on the idea of a visibility limit to serve as a pragmatic online detector. The average degree of the modified version of the natural visibility graph allows us to detect the onset of blowout, resulting in online prevention.

Control of an innovative super-capacitor-powered shape-memory-alloy actuated accumulator for blowout preventer

NASA Astrophysics Data System (ADS)

Chen, Jian; Li, Peng; Song, Gangbing; Ren, Zhang

2017-01-01

The design of a super-capacitor-powered shape-memory-alloy (SMA) actuated accumulator for blowout preventer (BOP) presented in this paper featured several advantages over conventional hydraulic accumulators including instant large current drive, quick system response and elimination of need for the pressure conduits. However, the mechanical design introduced two challenges, the nonlinear nature of SMA actuators and the varying voltage provided by a super capacitor, for control system design. A cerebellar model articulation controller (CMAC) feedforward plus PID controller was developed with the aim of compensation for these adverse effects. Experiments were conducted on a scaled down model and experimental results show that precision control can be achieved with the proposed configurations and algorithms.

30 CFR 250.515 - Blowout prevention equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... foreseeable conditions and circumstances, including subfreezing conditions. The working pressure rating of the BOP system and BOP system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the annular preventer, the...

30 CFR 250.516 - Blowout prevention equipment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pressure rating of the BOP system and BOP system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the...-control procedure that indicates how the annular preventer will be utilized, and the pressure limitations...

30 CFR 250.516 - Blowout prevention equipment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pressure rating of the BOP system and BOP system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the...-control procedure that indicates how the annular preventer will be utilized, and the pressure limitations...

30 CFR 250.515 - Blowout prevention equipment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pressure rating of the BOP system and BOP system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the...-control procedure that indicates how the annular preventer will be utilized, and the pressure limitations...

Blowout Prevention Act of 2010

THOMAS, 111th Congress

Rep. Waxman, Henry A. [D-CA-30

2010-06-29

House - 07/29/2010 Reported (Amended) by the Committee on Energy and Commerce. H. Rept. 111-581, Part I. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

An Anaylsis of Control Requirements and Control Parameters for Direct-Coupled Turbojet Engines

NASA Technical Reports Server (NTRS)

Novik, David; Otto, Edward W.

1947-01-01

Requirements of an automatic engine control, as affected by engine characteristics, have been analyzed for a direct-coupled turbojet engine. Control parameters for various conditions of engine operation are discussed. A hypothetical engine control is presented to illustrate the use of these parameters. An adjustable speed governor was found to offer a desirable method of over-all engine control. The selection of a minimum value of fuel flow was found to offer a means of preventing unstable burner operation during steady-state operation. Until satisfactory high-temperature-measuring devices are developed, air-fuel ratio is considered to be a satisfactory acceleration-control parameter for the attainment of the maximum acceleration rates consistent with safe turbine temperatures. No danger of unstable burner operation exists during acceleration if a temperature-limiting acceleration control is assumed to be effective. Deceleration was found to be accompanied by the possibility of burner blow-out even if a minimum fuel-flow control that prevents burner blow-out during steady-state operation is assumed to be effective. Burner blow-out during deceleration may be eliminated by varying the value of minimum fuel flow as a function of compressor-discharge pressure, but in no case should the fuel flow be allowed to fall below the value required for steady-state burner operation.

30 CFR 250.446 - What are the BOP maintenance and inspection requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.446 What are the... Prevention Equipment Systems for Drilling Wells (incorporated by reference as specified in § 250.198). You...

30 CFR 250.1706 - What are the requirements for blowout prevention equipment?

Code of Federal Regulations, 2014 CFR

2014-07-01

... circumstances, including subfreezing conditions. The working pressure rating of the BOP system and system components must exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the annular preventer, you must submit with Form BSEE-0124...

30 CFR 250.1706 - What are the requirements for blowout prevention equipment?

Code of Federal Regulations, 2013 CFR

2013-07-01

... circumstances, including subfreezing conditions. The working pressure rating of the BOP system and system components must exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the annular preventer, you must submit with Form BSEE-0124...

30 CFR 250.448 - What are the BOP pressure tests requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.448 What are the BOP...

30 CFR 250.448 - What are the BOP pressure tests requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.448 What are the BOP...

30 CFR 250.448 - What are the BOP pressure tests requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.448 What are the BOP...

[Micro-community characteristics of vegetations in blowouts and depositional areas of Hulunbuir grassland, Inner Mongolia].

PubMed

Man, Liang; Hasi, Eerdun; Zhang, Ping; Yan, Xu; Xia, Xian-Dong

2008-10-01

By using traditional sampling methods, the micro-communities of vegetations in fixed, semi-bare, and bare blowouts of Hulunbuir grassland were investigated, and the investigation data were statistical analyzed. The results showed that the vegetation coverage decreased in the order of fixed blowout, semi-bare blowout, and bare blowout, and was lower than that of the primary vegetation Form. Stipa grandis. Potentilla acaulis and Kengia squarrosa were the dominant species in fixed blowout, with the coverage being 5%; while P. acaulis and Carex sp. were the dominant species in semi-bare blowout, with the coverage being 2%. The dominant species in depositional areas of semi-bare blowout were P. acaulis, K. squarrosa, Agropyron cristatum, and Thymus mongolicus, and the coverage was 4%. The dominant species on the southwest slope of bare blowout was Agriophyllum pungens. The middle depositional area of bare blowout was also occupied by A. pungens (coverage 4.7%), and the edge of it was dominated by A. cristatum (coverage 2.7%), Carex sp. (coverage 2.6%), and T. mongolicus (coverage 1.7%) from the edge of the depositional area to primary grassland. The mean species importance value in fixed, semi-bare, and bare blowouts was 12.64%, 13.38%, and 20.08%, while that in the depositional area of semi-bare blowout and in the middle and edge of bare blowout was 12.55%, 40.18%, and 11.15%, respectively.

30 CFR 250.448 - What are the BOP pressure tests requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.448 What are the...

30 CFR 250.440 - What are the general requirements for BOP systems and system components?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements...

30 CFR 250.440 - What are the general requirements for BOP systems and system components?

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.440 What...

30 CFR 250.440 - What are the general requirements for BOP systems and system components?

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.440 What...

30 CFR 250.440 - What are the general requirements for BOP systems and system components?

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.440 What...

Morphometrics of aeolian blowouts from high-resolution digital elevation data: methodological considerations, shape metrics, and scaling

NASA Astrophysics Data System (ADS)

Hamilton, T. K.; Duke, G.; Brown, O.; Koenig, D.; Barchyn, T. E.; Hugenholtz, C.

2011-12-01

Aeolian blowouts are wind erosion hollows that form in vegetated aeolian landscapes. They are especially pervasive in dunefields of the northern Great Plains, yielding highly pitted or hummocky terrain, and adding to the spatial variability of microenvironments. Their development is thought to be linked to feedbacks between morphology and airflow; however, few measurements are available to test this hypothesis. Currently, a dearth of morphology data is limiting modeling progress. From a systematic program of blowout mapping with high-resolution airborne LiDAR data, we used a GIS to calculate morphometrics for 1373 blowouts in Great Sand Hills, Saskatchewan, Canada. All of the blowouts selected for this investigation were covered by grassland vegetation and inactive; their morphology represents the final stage of evolution. We first outline methodological considerations for delineating blowouts and measuring their volume. In particular, we present an objective method to enhance edge and reduce operator error and bias. We show that blowouts are slightly elongate and 49% of the sample blowouts are oriented parallel to the prevailing westerly winds. We also show that their size distribution is heavy-tailed, meaning that most blowouts are relatively small and rarely increase in size beyond 400 m3. Given that blowout growth is dominated by a positive feedback between sediment transport and vegetation erosion, these results suggest several possible mechanisms: i) blowouts simultaneously evolved and stabilized as a result of external climate forcing, ii) blowouts are slaved to exogenous biogenic disturbance patterns (e.g., bison wallows), or iii) a morphodynamic limiting mechanism restricts blowout size. Overall, these data will serve as a foundation for future study, providing insight into an understudied landform that is common in many dunefields.

30 CFR 250.515 - Blowout prevention equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 250.515 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT... be equipped with the following: (1) A hydraulic-actuating system that provides sufficient accumulator... manual overrides, or alternately, other devices provided to ensure capability of hydraulic operations if...

30 CFR 250.450 - What are the recordkeeping requirements for BOP tests?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.450 What are the... the duration of drilling. ...

30 CFR 250.450 - What are the recordkeeping requirements for BOP tests?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.450 What are the... the duration of drilling. ...

30 CFR 250.450 - What are the recordkeeping requirements for BOP tests?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.450 What are the... the duration of drilling. ...

30 CFR 250.440 - What are the general requirements for BOP systems and system components?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.440 What are the general...

76 FR 81957 - Mobile Offshore Drilling Unit Guidance Policy

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-29

... Purpose Dynamic Positioning Systems (DPSs), Emergency Disconnect Systems (EDSs), Blowout Preventers (BOPs..., ``Dynamically Positioned Mobile Offshore Drilling Unit (MODU) Critical Systems, Personnel and Training.'' We... association, business, labor union, etc.). You may review a Privacy Act, system of records notice regarding...

Numerical simulations of the Macondo well blowout reveal strong control of oil flow by reservoir permeability and exsolution of gas

PubMed Central

Oldenburg, Curtis M.; Freifeld, Barry M.; Pruess, Karsten; Pan, Lehua; Finsterle, Stefan; Moridis, George J.

2012-01-01

In response to the urgent need for estimates of the oil and gas flow rate from the Macondo well MC252-1 blowout, we assembled a small team and carried out oil and gas flow simulations using the TOUGH2 codes over two weeks in mid-2010. The conceptual model included the oil reservoir and the well with a top boundary condition located at the bottom of the blowout preventer. We developed a fluid properties module (Eoil) applicable to a simple two-phase and two-component oil-gas system. The flow of oil and gas was simulated using T2Well, a coupled reservoir-wellbore flow model, along with iTOUGH2 for sensitivity analysis and uncertainty quantification. The most likely oil flow rate estimated from simulations based on the data available in early June 2010 was about 100,000 bbl/d (barrels per day) with a corresponding gas flow rate of 300 MMscf/d (million standard cubic feet per day) assuming the well was open to the reservoir over 30 m of thickness. A Monte Carlo analysis of reservoir and fluid properties provided an uncertainty distribution with a long tail extending down to 60,000 bbl/d of oil (170 MMscf/d of gas). The flow rate was most strongly sensitive to reservoir permeability. Conceptual model uncertainty was also significant, particularly with regard to the length of the well that was open to the reservoir. For fluid-entry interval length of 1.5 m, the oil flow rate was about 56,000 bbl/d. Sensitivity analyses showed that flow rate was not very sensitive to pressure-drop across the blowout preventer due to the interplay between gas exsolution and oil flow rate. PMID:21730177

Independent Technical Investigation of the Puna Geothermal Venture Unplanned Steam Release, June 12 and 13, 1991, Puna, Hawaii

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

Thomas, Richard; Whiting, Dick; Moore, James

1991-07-01

On June 24, 1991, a third-party investigation team consisting of Richard P. Thomas, Duey E. Milner, James L. Moore, and Dick Whiting began an investigation into the blowout of well KS-8, which occurred at the Puna Geothermal Venture (PGV) site on June 12, 1991, and caused the unabated release of steam for a period of 31 hours before PGV succeeded in closing in the well. The scope of the investigation was to: (a) determine the cause(s) of the incident; (b) evaluate the adequacy of PGVs drilling and blowout prevention equipment and procedures; and (c) make recommendations for any appropriate changesmore » in equipment and/or procedures. This report finds that the blowout occurred because of inadequacies in PGVs drilling plan and procedures and not as a result of unusual or unmanageable subsurface geologic or hydrologic conditions. While the geothermal resource in the area being drilled is relatively hot, the temperatures are not excessive for modem technology and methods to control. Fluid pressures encountered are also manageable if proper procedures are followed and the appropriate equipment is utilized. A previous blowout of short duration occurred on February 21, 1991, at the KS-7 injection well being drilled by PGV at a depth of approximately 1600'. This unexpected incident alerted PGV to the possibility of encountering a high temperature, fractured zone at a relatively shallow depth. The experience at KS-7 prompted PGV to refine its hydrological model; however, the drilling plan utilized for KS-8 was not changed. Not only did PGV fail to modify its drilling program following the KS-7 blowout, but they also failed to heed numerous ''red flags'' (warning signals) in the five days preceding the KS-8 blowout, which included a continuous 1-inch flow of drilling mud out of the wellbore, gains in mud volume while pulling stands, and gas entries while circulating muds bottoms up, in addition to lost circulation that had occurred earlier below the shoe of the 13-3/8-hch casing.« less

Systems and methods for detection of blowout precursors in combustors

DOEpatents

Lieuwen, Tim C.; Nair, Suraj

2006-08-15

The present invention comprises systems and methods for detecting flame blowout precursors in combustors. The blowout precursor detection system comprises a combustor, a pressure measuring device, and blowout precursor detection unit. A combustion controller may also be used to control combustor parameters. The methods of the present invention comprise receiving pressure data measured by an acoustic pressure measuring device, performing one or a combination of spectral analysis, statistical analysis, and wavelet analysis on received pressure data, and determining the existence of a blowout precursor based on such analyses. The spectral analysis, statistical analysis, and wavelet analysis further comprise their respective sub-methods to determine the existence of blowout precursors.

Inductive shearing of drilling pipe

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

Ludtka, Gerard M.; Wilgen, John; Kisner, Roger

Induction shearing may be used to cut a drillpipe at an undersea well. Electromagnetic rings may be built into a blow-out preventer (BOP) at the seafloor. The electromagnetic rings create a magnetic field through the drillpipe and may transfer sufficient energy to change the state of the metal drillpipe to shear the drillpipe. After shearing the drillpipe, the drillpipe may be sealed to prevent further leakage of well contents.

Holocene Development and Progression of Aeolian Blowouts on Padre Island National Seashore

NASA Astrophysics Data System (ADS)

Jewell, M. E.; Houser, C.

2012-12-01

Recent evidence suggests that development of dune blowouts along Padre Island National Seashore, Texas, and migration of the parabolic dunes to the backbarrier shoreline are the primary mechanisms by which the island transgresses in response to relative sea level rise. This study characterizes the development and migration of dune blowouts at decadal and century scales in order to understand these changes. An initial breach, caused by the removal of vegetation, develops along the dune line allowing sediment to be funneled into the dune field. The entrance of the blowout focuses the wind velocity, allowing sediment to be transported into the dune field, covering any vegetation that is present. This process continues as sediment is eroded from the foredune increasing the size of the blowout until the foredune is rebuilt and vegetation stabilizes the entrance. With the front stabilized, the blowout begins its movement across the island. Aerial photographs, LIDAR data, ground penetrating radar, and optically stimulated luminescence were used to track and date the migration of these blowouts. Photographs and satellite images, taken at least twice a decade since the 1940s, were used to track blowouts from their initial conception to their final stabilization by vegetation. Each consecutive blowout was digitized to understand the surface characteristics of the feature. For a greater understanding of the system at the decadal scale, LIDAR data collected by the USGS and other agencies was used to create an elevation model in order compute the volumetric changes within the northern portion of the National Seashore. Within the larger study area, three smaller sites: a young blowout that had just begun to close as the foredune is reestablished, a "middle age" blowout that was detached from the foredune and become an active dune field, and a former blowout now stabilized by vegetation, were selected for geophysical analysis . A Trimble GX 3-D scanner was used to determine the current volume of the blowouts and to create an end point for the elevation model at the smaller scale. Then a ground penetrating radar survey was completed at both dune normal and the average direction of travel for each blowout to show the bounding layers, cross stratification, and bedding planes of the migrating blowout without physical disruption. Vibracoring and optically stimulated luminescence provided a physical comparison of the stratigraphy to the data returned in the GPR survey. By using this comparison, sediment type, structures, and burial age are compared to geomorphic properties to determine the abundance of storms, sediment budget, and vegetation extent, which are key characteristics in understanding blowouts. These factors are integral in understanding how the blowouts have changed over the past 70 years and how these variables will affect evolution and spatial distribution of the shoreline.

Well blowout rates in California Oil and Gas District 4--Update and Trends

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

Jordan, Preston D.; Benson, Sally M.

2009-10-01

Well blowouts are one type of event in hydrocarbon exploration and production that generates health, safety, environmental and financial risk. Well blowouts are variously defined as 'uncontrolled flow of well fluids and/or formation fluids from the wellbore' or 'uncontrolled flow of reservoir fluids into the wellbore'. Theoretically this is irrespective of flux rate and so would include low fluxes, often termed 'leakage'. In practice, such low-flux events are not considered well blowouts. Rather, the term well blowout applies to higher fluxes that rise to attention more acutely, typically in the order of seconds to days after the event commences. Itmore » is not unusual for insurance claims for well blowouts to exceed US$10 million. This does not imply that all blowouts are this costly, as it is likely claims are filed only for the most catastrophic events. Still, insuring against the risk of loss of well control is the costliest in the industry. The risk of well blowouts was recently quantified from an assembled database of 102 events occurring in California Oil and Gas District 4 during the period 1991 to 2005, inclusive. This article reviews those findings, updates them to a certain extent and compares them with other well blowout risk study results. It also provides an improved perspective on some of the findings. In short, this update finds that blowout rates have remained constant from 2005 to 2008 within the limits of resolution and that the decline in blowout rates from 1991 to 2005 was likely due to improved industry practice.« less

16 CFR 1507.6 - Burnout and blowout.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Burnout and blowout. 1507.6 Section 1507.6... FIREWORKS DEVICES § 1507.6 Burnout and blowout. The pyrotechnic chamber in fireworks devices shall be constructed in a manner to allow functioning in a normal manner without burnout or blowout. ...

16 CFR 1507.6 - Burnout and blowout.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Burnout and blowout. 1507.6 Section 1507.6... FIREWORKS DEVICES § 1507.6 Burnout and blowout. The pyrotechnic chamber in fireworks devices shall be constructed in a manner to allow functioning in a normal manner without burnout or blowout. ...

16 CFR 1507.6 - Burnout and blowout.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Burnout and blowout. 1507.6 Section 1507.6... FIREWORKS DEVICES § 1507.6 Burnout and blowout. The pyrotechnic chamber in fireworks devices shall be constructed in a manner to allow functioning in a normal manner without burnout or blowout. ...

16 CFR 1507.6 - Burnout and blowout.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Burnout and blowout. 1507.6 Section 1507.6... FIREWORKS DEVICES § 1507.6 Burnout and blowout. The pyrotechnic chamber in fireworks devices shall be constructed in a manner to allow functioning in a normal manner without burnout or blowout. ...

30 CFR 250.615 - Blowout prevention equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 250.615 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT...) A hydraulic-actuating system that provides sufficient accumulator capacity to supply 1.5 times the..., other devices provided to ensure capability of hydraulic operations if rig air is lost; (2) A secondary...

16 CFR § 1507.6 - Burnout and blowout.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Burnout and blowout. § 1507.6 Section Â... REGULATIONS FIREWORKS DEVICES § 1507.6 Burnout and blowout. The pyrotechnic chamber in fireworks devices shall be constructed in a manner to allow functioning in a normal manner without burnout or blowout. ...

Remediation of blowouts by clonal plants in Maqu degraded alpine grasslands of northwest China.

PubMed

Kang, JianJun; Zhao, WenZhi; Zhao, Ming

2017-03-01

The sand-fixation of plants is considered to be the most effective and fundamental measure in desertification control in many arid and semi-arid regions. Carex brunnescens (Carex spp) and Leymus secalinus (Leymus), two perennial clonal herbs native to the Maqu degraded alpine areas of northwest China, are dominant and constructive species in active sand dunes that have excellent adaptability to fix sand dunes found to date. In order to study the ability and mechanism of sandland blowout remediation by two clone plants C. brunnescens and L. secalinus, the artificially emulated blowouts were set up in the populations of two clonal plants in the field. The results showed that both C. brunnescens and L. secalinus produced more new ramets in the artificially emulated blowouts than in the natural conditions, suggesting that the two clonal plants had strong ability in blowouts remediation; while the biomass, number of leaves and height of new ramets in the artificially emulated blowouts were less than in the natural conditions due to the restriction of poor nutrients in the artificially emulated blowouts. The ability of blowouts remediation by C. brunnescens was stronger than L. secalinus, as it generated more new ramets than L. secalinus in the process of blowouts remediation. The new ramets of L. secalinus in the blowouts remediation were mainly generated by the buds in the rhizomes which spread from outside of the blowouts; while those of C. brunnescens were generated both by the buds in the rhizomes which spread from outside, and by the buds in the rhizomes inside which were freed from dormancy in the deeper soil under wind erosion conditions. These findings suggest that through rapid clonal expansion capability, C. brunnescens and L. secalinus exhibited strong ability in blowouts remediation which can be one of the most effective strategies to restore and reconstruct degraded vegetations in Maqu alpine areas of northwest China.

30 CFR 250.450 - What are the recordkeeping requirements for BOP tests?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.450 What are the... the duration of drilling. [68 FR 8423, Feb. 20, 2003] ...

30 CFR 250.615 - Blowout prevention equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... be applied during each mode of pressure control. (b) The minimum BOP system for well-workover operations with the tree removed must meet the appropriate standards from the following table: When The... for well-workover operations with the tree removed must be equipped with the following: (1) A...

What if Things Get Worse? Really Grand Challenges for Modeling and Simulation in a Risky and Complex World or Modeling and Simulation for the "Greater Good"?

NASA Technical Reports Server (NTRS)

Fifrey, Priscilla

2010-01-01

Today Modeling and Simulation-- ---as an important practice or industry or area of expertise ----- is at a complex crossroad - a sort of cyber-highway--where these complexities meet-technical, economic, environmental, geopolitical and cultural. They may converge or collide. Let's not kid ourselves. It is all too much for anyone person or organization Malcolm Gladwell said it. "We have constructed a world in which the potential for high tech catastrophe is embedded in the fabric of everyday life." We are surrounded by problems that scream at us from our television, Internet and social networks along with billboards and protest signs. We face not just high tech catastrophes but, also, landslides, earthquakes, tornados, floods and hurricanes and large-scale criminality. Evil, war, famine and pestilence have not gone away. It is all too much to think about. My friend, George Peabody, who taught me everything I know about power said that addressing such issues requires that we constantly build our network, information resources and the credibility and visibility of our work. That is how we will build the power of simulation so it can change the world --even maybe, save it. We need all the help we can get and give one another because our human early warning systems appear to be out of kilter. We seem to have trouble imagining how small failings can continue to lead to catastrophic disaster. Think about O-rings and blowout preventers. One is reminded of the old nursery rhyme, "For want of a nail, a shoe was lost! for want of a shoe the horse was lost! for want of a rider the battle was lost and so the kingdom fell." Although the investigation will take more time for real answers, it is worrisome that a rig worker reported to the BBC that-- weeks before the explosion of Deep Ocean Horizon. -he identified a leak in the oil rig's safety equipment -the Control Pod of the blowout preventer which has giant shears designed to cut and seal off the well's main pipe. With both electronics and hydraulics, these are effectively the brains of the blowout preventer. No one fixed it, he alleges, they just shut it down and relied on the other control pod -an act deemed unacceptable by petroleum expert, Tad Patzek, at the University of Texas. The US Congress has identified numerous other problems with the blowout preventer, including design problems and unexpected modifications.

30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.444 What are the choke... corrosiveness, volume, and abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke...

30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.444 What are the choke manifold..., and abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke manifold...

30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.444 What are the choke manifold..., and abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke manifold...

30 CFR 250.444 - What are the choke manifold requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.444 What are the choke manifold..., and abrasiveness of drilling fluids and well fluids that you may encounter. (b) Choke manifold...

30 CFR 250.616 - Blowout prevention equipment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pressure rating of the BOP system and system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the... pressure limitations that will be applied during each mode of pressure control. (b) The minimum BOP system...

30 CFR 250.616 - Blowout prevention equipment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pressure rating of the BOP system and system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the... pressure limitations that will be applied during each mode of pressure control. (b) The minimum BOP system...

30 CFR 250.615 - Blowout prevention equipment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pressure rating of the BOP system and system components shall exceed the expected surface pressure to which they may be subjected. If the expected surface pressure exceeds the rated working pressure of the... pressure limitations that will be applied during each mode of pressure control. (b) The minimum BOP system...

76 FR 49666 - Safety Zone; East Coast Drag Boat Bucksport Blowout Boat Race, Waccamaw River, Bucksport, SC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-11

...-AA00 Safety Zone; East Coast Drag Boat Bucksport Blowout Boat Race, Waccamaw River, Bucksport, SC... temporary safety zone on the waters of the Waccamaw River during the East Coast Drag Boat Bucksport Blowout in Bucksport, South Carolina. The East Coast Drag Boat Bucksport Blowout will consist of a series of...

Zebrafish blowout provides genetic evidence for Patched1-mediated negative regulation of Hedgehog signaling within the proximal optic vesicle of the vertebrate eye.

PubMed

Lee, Jiwoon; Willer, Jason R; Willer, Gregory B; Smith, Kierann; Gregg, Ronald G; Gross, Jeffrey M

2008-07-01

In this study, we have characterized the ocular defects in the recessive zebrafish mutant blowout that presents with a variably penetrant coloboma phenotype. blowout mutants develop unilateral or bilateral colobomas and as a result, the retina and retinal pigmented epithelium are not contained within the optic cup. Colobomas result from defects in optic stalk morphogenesis whereby the optic stalk extends into the retina and impedes the lateral edges of the choroid fissure from meeting and fusing. The expression domain of the proximal optic vesicle marker pax2a is expanded in blowout at the expense of the distal optic vesicle marker pax6, suggesting that the initial patterning of the optic vesicle into proximal and distal territories is disrupted in blowout. Later aspects of distal optic cup formation (i.e. retina development) are normal in blowout mutants, however. Positional cloning of blowout identified a nonsense mutation in patched1, a negative regulator of the Hedgehog pathway, as the underlying cause of the blowout phenotype. Expanded domains of expression of the Hedgehog target genes patched1 and patched2 were observed in blowout, consistent with a loss of Patched1 function and upregulation of Hedgehog pathway activity. Moreover, colobomas in blowout could be suppressed by pharmacologically inhibiting the Hedgehog pathway with cyclopamine, and maximal rescue occurred when embryos were exposed to cyclopamine between 5.5 and 13 hours post-fertilization. These observations highlight the critical role that Hedgehog pathway activity plays in mediating patterning of the proximal/distal axis of the optic vesicle during the early phases of eye development and they provide genetic confirmation for the integral role that patched1-mediated negative regulation of Hedgehog signaling plays during vertebrate eye development.

Zebrafish blowout provides genetic evidence for Patched1 mediated negative regulation of Hedgehog signaling within the proximal optic vesicle of the vertebrate eye

PubMed Central

Lee, Jiwoon; Willer, Jason R.; Willer, Gregory B.; Smith, Kierann; Gregg, Ronald G.; Gross, Jeffrey M.

2008-01-01

In this study we have characterized the ocular defects in the recessive zebrafish mutant blowout that presents with a variably penetrant coloboma phenotype. blowout mutants develop unilateral or bilateral colobomas and as a result, the retina and retinal pigmented epithelium are not contained within the optic cup. Colobomas result from defects in optic stalk morphogenesis whereby the optic stalk extends into the retina and impedes the lateral edges of the choroid fissure from meeting and fusing. The expression domain of the proximal optic vesicle marker pax2a is expanded in blowout at the expense of the distal optic vesicle marker pax6, suggesting that the initial patterning of the optic vesicle into proximal and distal territories is disrupted in blowout. Later aspects of distal optic cup formation (i.e. retina development) are normal in blowout mutants, however. Positional cloning of blowout identified a nonsense mutation in patched1, a negative regulator of the Hedgehog pathway, as the underlying cause of the blowout phenotype. Expanded domains of expression of the Hedgehog target genes patched1 and patched2 were observed in blowout, consistent with a loss of Patched1 function and upregulation of Hedgehog pathway activity. Moreover, colobomas in blowout could be suppressed by pharmacologically inhibiting the Hedgehog pathway with cyclopamine, and maximal rescue occurred when embryos were exposed to cyclopamine between 5.5 and 13 hours post fertilization. These observations highlight the critical role that Hedgehog pathway activity plays in mediating patterning of the proximal/distal axis of the optic vesicle during the early phases of eye development and they provide genetic confirmation for the integral role that patched1-mediated negative regulation of Hedgehog signaling plays during vertebrate eye development. PMID:18479681

Flow and sediment transport dynamics in a slot and cauldron blowout and over a foredune, Mason Bay, Stewart Island (Rakiura), NZ

NASA Astrophysics Data System (ADS)

Hesp, Patrick A.; Hilton, Michael; Konlecher, Teresa

2017-10-01

This study is the first to simultaneously compare flow and sediment transport through a blowout and over an adjacent foredune, and the first study of flow within a highly sinuous, slot and cauldron blowout. Flow across the foredune transect is similar to that observed in other studies and is primarily modulated by across-dune vegetation density differences. Flow within the blowout is highly complex and exhibits pronounced accelerations and jet flow. It is characterised by marked helicoidal coherent vortices in the mid-regions, and topographically vertically forced flow out of the cauldron portion of the blowout. Instantaneous sediment transport within the blowout is significant compared to transport onto and/or over the adjacent foredune stoss slope and ridge, with the blowout providing a conduit for suspended sediment to reach the downwind foredune upper stoss slope and crest. Medium term (4 months) aeolian sedimentation data indicates sand is accumulating in the blowout entrance while erosion is taking place throughout the majority of the slot, and deposition is occurring downwind of the cauldron on the foredune ridge. The adjacent lower stoss slope of the foredune is accreting while the upper stoss slope is slightly erosional. Longer term (16 months) pot trap data shows that the majority of foredune upper stoss slope and crest accretion occurs via suspended sediment delivery from the blowout, whereas the majority of the suspended sediment arriving to the well-vegetated foredune stoss slope is deposited on the mid-stoss slope. The results of this study indicate one mechanism of how marked alongshore foredune morphological variability evolves due to the role of blowouts in topographically accelerating flow, and delivering significant aeolian sediment downwind to relatively discrete sections of the foredune.

Oil release from Macondo well MC252 following the Deepwater Horizon accident.

PubMed

Griffiths, Stewart K

2012-05-15

Oil flow rates and cumulative discharge from the BP Macondo Prospect well in the Gulf of Mexico are calculated using a physically based model along with wellhead pressures measured at the blowout preventer (BOP) over the 86-day period following the Deepwater Horizon accident. Parameters appearing in the model are determined empirically from pressures measured during well shut-in and from pressures and flow rates measured the preceding day. This methodology rigorously accounts for ill-characterized evolution of the marine riser, installation and removal of collection caps, and any erosion at the wellhead. The calculated initial flow rate is 67,100 stock-tank barrels per day (stbd), which decays to 54,400 stbd just prior to installation of the capping stack and subsequent shut-in. The calculated cumulative discharge is 5.4 million stock-tank barrels, of which 4.6 million barrels entered the Gulf. Quantifiable uncertainties in these values are -9.3% and +7.5%, yielding a likely total discharge in the range from 4.9 to 5.8 million barrels. Minimum and maximum credible values of this discharge are 4.6 and 6.2 million barrels. Alternative calculations using the reservoir and sea-floor pressures indicate that any erosion within the BOP had little affect on cumulative discharge.

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

Milgram, J.; Erb, P.R.

A study of the behavior of floating drilling vessels during blowouts included: (1) a survey of actual incidents, (2) development of a computer model of a vessel in a blowout, and (3) large-scale experiments with a floating object in a bubble plume. The results disproved the common belief that a floating vessel will sink suddenly if a subsea blowout occurs below it. Actually, the average vertical support force changes very little in a blowout; in fact, a net upward force may result if the upwelling water flow overcomes the slight loss of fluid density due to bubbles. However, the currentsmore » caused by a blowout plume can make the vessel tip or oscillate.« less

78 FR 72688 - Information Collection Activities: Application for Permit To Drill; Proposed Collection; Comment...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-03

... and natural gas resources in a manner that is consistent with the need to make such resources... prevent or minimize the likelihood of blowouts, loss of well control, fires, spillages, physical... the environment or to property or endanger life or health.'' In addition to the general rulemaking...

77 FR 28401 - Information Collection Activities: Legacy Data Verification Process (LDVP); Submitted for Office...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-14

... and natural gas resources in a manner that is consistent with the need to make such resources... to prevent or minimize the likelihood of blowouts, loss of well control, fires, spillages, physical... the environment or to property, or endanger life or health.'' BSEE's Legacy Data Verification Process...

30 CFR 250.616 - Blowout preventer system testing, records, and drills.

Code of Federal Regulations, 2011 CFR

2011-07-01

... drills. 250.616 Section 250.616 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... drills. (a) BOP pressure tests. When you pressure test the BOP system you must conduct a low-pressure... engaged in well-workover operations shall participate in a weekly BOP drill to familiarize crew members...

30 CFR 250.447 - When must I pressure test the BOP system?

Code of Federal Regulations, 2013 CFR

2013-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.447 When must I pressure test the BOP... BOP, and drill-string safety valve): (a) When installed; (b) Before 14 days have elapsed since your...

30 CFR 250.445 - What are the requirements for kelly valves, inside BOPs, and drill-string safety valves?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., inside BOPs, and drill-string safety valves? 250.445 Section 250.445 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System...

30 CFR 250.447 - When must I pressure test the BOP system?

Code of Federal Regulations, 2012 CFR

2012-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.447 When must I pressure test the BOP... BOP, and drill-string safety valve): (a) When installed; (b) Before 14 days have elapsed since your...

30 CFR 250.434 - What are the recordkeeping requirements for diverter actuations and tests?

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Diverter System Requirements § 250.434 What are the recordkeeping... the facility for the duration of drilling the well. Blowout Preventer (BOP) System Requirements ...

30 CFR 250.449 - What additional BOP testing requirements must I meet?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.449 What additional BOP... water to conduct this test. You may use drilling fluids to conduct subsequent tests of a subsea BOP...

30 CFR 250.449 - What additional BOP testing requirements must I meet?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.449 What additional BOP... water to conduct this test. You may use drilling fluids to conduct subsequent tests of a subsea BOP...

30 CFR 250.451 - What must I do in certain situations involving BOP equipment or systems?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements... drilling activities. If you encounter the following situation: Then you must . . . (a) BOP equipment does...

30 CFR 250.447 - When must I pressure test the BOP system?

Code of Federal Regulations, 2014 CFR

2014-07-01

... THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.447 When must I pressure test the BOP... BOP, and drill-string safety valve): (a) When installed; (b) Before 14 days have elapsed since your...

30 CFR 250.446 - What are the BOP maintenance and inspection requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.446 What are the BOP... for Drilling Wells (as incorporated by reference in § 250.198). You must document the procedures used...

30 CFR 250.434 - What are the recordkeeping requirements for diverter actuations and tests?

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Diverter System Requirements § 250.434 What are the recordkeeping... the facility for the duration of drilling the well. Blowout Preventer (BOP) System Requirements ...

30 CFR 250.447 - When must I pressure test the BOP system?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.447 When must I pressure... valves, inside BOP, and drill-string safety valve): (a) When installed; (b) Before 14 days have elapsed...

30 CFR 250.445 - What are the requirements for kelly valves, inside BOPs, and drill-string safety valves?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., inside BOPs, and drill-string safety valves? 250.445 Section 250.445 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System...

30 CFR 250.445 - What are the requirements for kelly valves, inside BOPs, and drill-string safety valves?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., inside BOPs, and drill-string safety valves? 250.445 Section 250.445 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System...

30 CFR 250.449 - What additional BOP testing requirements must I meet?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.449 What... installation. You must use water to conduct this test. You may use drilling fluids to conduct subsequent tests...

30 CFR 250.446 - What are the BOP maintenance and inspection requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.446 What are the BOP... for Drilling Wells (incorporated by reference as specified in § 250.198). You must document how you...

30 CFR 250.446 - What are the BOP maintenance and inspection requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.446 What are the BOP... for Drilling Wells (incorporated by reference as specified in § 250.198). You must document how you...

30 CFR 250.434 - What are the recordkeeping requirements for diverter actuations and tests?

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Diverter System Requirements § 250.434 What are the recordkeeping... the facility for the duration of drilling the well. Blowout Preventer (BOP) System Requirements ...

30 CFR 250.449 - What additional BOP testing requirements must I meet?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.449 What additional BOP... water to conduct this test. You may use drilling fluids to conduct subsequent tests of a subsea BOP...

30 CFR 250.443 - What associated systems and related equipment must all BOP systems include?

Code of Federal Regulations, 2011 CFR

2011-07-01

... MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System... must be on the drilling floor. You must locate the other station in a readily accessible location away...

30 CFR 250.516 - Blowout preventer system tests, inspections, and maintenance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... inspection, whichever is longer. (2) You must visually inspect your BOP system and marine riser at least once.... The District Manager may approve alternate methods and frequencies to inspect a marine riser. (h) BOP... drills, and inspections of the BOP system, system components, and marine riser in the driller's report...

30 CFR 250.517 - Blowout preventer system tests, inspections, and maintenance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... on a daily basis. You must visually inspect your subsea BOP system and marine riser at least once... equipment. The BSEE District Manager may approve alternate methods and frequencies to inspect a marine riser..., actuations, crew drills, and inspections of the BOP system, system components, and marine riser in the...

30 CFR 250.517 - Blowout preventer system tests, inspections, and maintenance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... on a daily basis. You must visually inspect your subsea BOP system and marine riser at least once... equipment. The BSEE District Manager may approve alternate methods and frequencies to inspect a marine riser..., actuations, crew drills, and inspections of the BOP system, system components, and marine riser in the...

76 FR 50748 - Information Collection Activity: Production Safety Systems, Revision of a Collection; Submitted...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-16

... Production Safety Systems. OMB Control Number: 1010-0059. Abstract: The Outer Continental Shelf (OCS) Lands..., precautions, and techniques sufficient to prevent or minimize the likelihood of blowouts, loss of well control... an identifiable non-Federal recipient above and beyond those which accrue to the public at large...

Morphological response of a large-scale coastal blowout to a strong magnitude transport event

NASA Astrophysics Data System (ADS)

Delgado-Fernandez, Irene; Jackson, Derek; Smith, Alexander; Smyth, Thomas

2017-04-01

Large-scale blowouts are fundamental features of many coastal dune fields in temperate areas around the world. These distinctive erosional (mostly unvegetated) landform features are often characterised by a significant depression area and a connected depositional lobe at their downwind edges. These areas also provide important transport corridors to inland parts of the dune system and can provide ideal habitats for specialist flora and fauna as well as helping to enhance landscape diversity. The actual morphology and shape/size of blowouts can significantly modify the overlying atmospheric boundary layer of the wind, influencing wind flow steering and intensity within the blowout, and ultimately aeolian sediment transport. While investigations of morphological changes within blowouts have largely focused on the medium (months) to long (annual/decadal) temporal scale, studies of aeolian transport dynamics within blowouts have predominantly focused on the short-term (event) scale. Work on wind-transport processes in blowouts is still relatively rare, with ad-hoc studies providing only limited information on airflow and aeolian transport. Large-scale blowouts are characterised by elongated basins that can reach hundreds of meters, potentially resulting in airflow and transport dynamics that are very different from their smaller scale counterparts. This research focuses on a short-term, strong wind event measured at the Devil's Hole blowout (Sefton dunes, NW England), a large-scale blowout feature approximately 300 m in length and 100 m in width. In situ measurements of airflow and aeolian transport were collected during a short-term experiment on the 22nd October 2015. A total of twenty three, 3D ultrasonic anemometers, sand traps, and wenglor sensors were deployed in a spatial grid covering the distal end of the basin, walls, and depositional lobe. Terrestrial laser scanning (TLS) was used to quantify morphological changes within the blowout before and after the strong magnitude transport event. This allowed, for the first time, examination of the morphological response as a direct result of a high energy wind event as it passes through a large-scale blowout. Results indicate strong steering and acceleration of the wind along the blowout basin and up the south wall opposite to the incident regional winds. These accelerated flows generated very strong transport rates of up to 3 g/s along the basin, and moderate strong transport rates of up to 1.5 g/s up the steep north wall. The coupling of high-frequency wind events and transport response together with topographic changes defined by TLS data allows, for the first time, the ability to co-connect the morphological evolution of a coastal blowout landform with the localised driving processes.

Blow-Out Velocities of Solutions of Hydrocarbons and Boron Hydride - Hydrocarbon Reaction Products in a 1 7/8-Inch-Diameter Combustor

NASA Technical Reports Server (NTRS)

Morris, James F.; Lord, Albert M.

1957-01-01

Blow-out velocities were determined for JP-4 solutions containing: (1) 10 % ethylene - decaborane reaction product, (2) 10% and 20% acetylene - diborane reaction product, and (3) 5.5%, 15.7%, and 30.7% methylacetylene - diborane reaction product. These were compared with blow-out velocities for JP-4, propylene oxide, and neohexane and previously reported data for JP-4 solutions of pentaborane. For those reaction products investigated, the blow-out velocities at a fixed equivalence ratio were higher for those materials containing higher boron concentrations; that is, blow-out velocity increased in the following order: (1) methylacetylene - diborane, (2) acetylene - diborane, and (3) ethylene - decaborane reaction products.

DICHOTOMY OF SOLAR CORONAL JETS: STANDARD JETS AND BLOWOUT JETS

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

Moore, Ronald L.; Cirtain, Jonathan W.; Sterling, Alphonse C.

2010-09-01

By examining many X-ray jets in Hinode/X-Ray Telescope coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H{alpha} macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major coronal mass ejections. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jetsmore » that were also caught in He II 304 A snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T {approx} 10{sup 4} - 10{sup 5} K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.« less

Dichotomy of Solar Coronal Jets: Standard Jets and Blowout Jets

NASA Technical Reports Server (NTRS)

Moore, R. L.; Cirtain, J. W.; Sterling, A. C.; Falconer, D. A.

2010-01-01

By examining many X-ray jets in Hinode/XRT coronal X-ray movies of the polar coronal holes, we found that there is a dichotomy of polar X-ray jets. About two thirds fit the standard reconnection picture for coronal jets, and about one third are another type. We present observations indicating that the non-standard jets are counterparts of erupting-loop H alpha macrospicules, jets in which the jet-base magnetic arch undergoes a miniature version of the blowout eruptions that produce major CMEs. From the coronal X-ray movies we present in detail two typical standard X-ray jets and two typical blowout X-ray jets that were also caught in He II 304 Angstrom snapshots from STEREO/EUVI. The distinguishing features of blowout X-ray jets are (1) X-ray brightening inside the base arch in addition to the outside bright point that standard jets have, (2) blowout eruption of the base arch's core field, often carrying a filament of cool (T 10(exp 4) - 10(exp 5) K) plasma, and (3) an extra jet-spire strand rooted close to the bright point. We present cartoons showing how reconnection during blowout eruption of the base arch could produce the observed features of blowout X-ray jets. We infer that (1) the standard-jet/blowout-jet dichotomy of coronal jets results from the dichotomy of base arches that do not have and base arches that do have enough shear and twist to erupt open, and (2) there is a large class of spicules that are standard jets and a comparably large class of spicules that are blowout jets.

30 CFR 250.443 - What associated systems and related equipment must all BOP systems include?

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.443 What... all BOP components. (b) At least two BOP control stations. One station must be on the drilling floor...

30 CFR 250.442 - What are the requirements for a subsea BOP system?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.442 What are the requirements for a subsea BOP system? When you drill with a subsea BOP system, you must install the BOP system...

30 CFR 250.451 - What must I do in certain situations involving BOP equipment or systems?

Code of Federal Regulations, 2013 CFR

2013-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.451 What must I... actions that lessees must take when certain situations occur with BOP systems during drilling activities...

30 CFR 250.445 - What are the requirements for kelly valves, inside BOPs, and drill-string safety valves?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., inside BOPs, and drill-string safety valves? 250.445 Section 250.445 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.445 What...

30 CFR 250.445 - What are the requirements for kelly valves, inside BOPs, and drill-string safety valves?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., inside BOPs, and drill-string safety valves? 250.445 Section 250.445 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop...

30 CFR 250.451 - What must I do in certain situations involving BOP equipment or systems?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.451 What must I do in... lessees must take when certain situations occur with BOP systems during drilling activities. If you...

30 CFR 250.442 - What are the requirements for a subsea BOP system?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.442 What are the requirements for a subsea BOP system? When you drill with a subsea BOP system, you must install the BOP system...

30 CFR 250.451 - What must I do in certain situations involving BOP equipment or systems?

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.451 What must I... actions that lessees must take when certain situations occur with BOP systems during drilling activities...

30 CFR 250.442 - What are the requirements for a subsea BOP system?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.442 What are the requirements for a subsea BOP system? When you drill with a subsea BOP system, you must install the BOP system...

30 CFR 250.442 - What are the requirements for a subsea BOP system?

Code of Federal Regulations, 2011 CFR

2011-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.442 What are the requirements for a subsea BOP system? When you drill with a subsea BOP system, you must install the BOP system...

30 CFR 250.443 - What associated systems and related equipment must all BOP systems include?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.443 What associated systems... components. (b) At least two BOP control stations. One station must be on the drilling floor. You must locate...

30 CFR 250.443 - What associated systems and related equipment must all BOP systems include?

Code of Federal Regulations, 2012 CFR

2012-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.443 What... all BOP components. (b) At least two BOP control stations. One station must be on the drilling floor...

30 CFR 250.443 - What associated systems and related equipment must all BOP systems include?

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.443 What... all BOP components. (b) At least two BOP control stations. One station must be on the drilling floor...

30 CFR 250.451 - What must I do in certain situations involving BOP equipment or systems?

Code of Federal Regulations, 2014 CFR

2014-07-01

... ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.451 What must I... actions that lessees must take when certain situations occur with BOP systems during drilling activities...

30 CFR 250.516 - Blowout preventer system tests, inspections, and maintenance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... marine riser at least once each day if weather and sea conditions permit. You may use television cameras... inspect a marine riser. (h) BOP maintenance. You must maintain your BOP system to ensure that the... components, and marine riser in the driller's report. In addition, you must: (1) Record BOP test pressures on...

30 CFR 250.1611 - Blowout preventer systems tests, actuations, inspections, and maintenance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conducting high-pressure tests, all BOP systems shall be tested to a pressure of 200 to 300 psi. (b) Ram-type BOP's and the choke manifold shall be pressure tested with water to rated working pressure or as otherwise approved by the District Manager. Annular type BOP's shall be pressure tested with water to 70...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

30 CFR 250.1624 - Blowout prevention equipment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... station and one BOP-control station on the rig floor; and (5) A choke line and a kill line each equipped with two full-opening valves and a choke manifold. One of the choke-line valves and one of the kill-line valves shall be remotely controlled except that a check valve may be installed on the kill line in...

Numerical simulation of water and sand blowouts when penetrating through shallow water flow formations in deep water drilling

NASA Astrophysics Data System (ADS)

Ren, Shaoran; Liu, Yanmin; Gong, Zhiwu; Yuan, Yujie; Yu, Lu; Wang, Yanyong; Xu, Yan; Deng, Junyu

2018-02-01

In this study, we applied a two-phase flow model to simulate water and sand blowout processes when penetrating shallow water flow (SWF) formations during deepwater drilling. We define `sand' as a pseudo-component with high density and viscosity, which can begin to flow with water when a critical pressure difference is attained. We calculated the water and sand blowout rates and analyzed the influencing factors from them, including overpressure of the SWF formation, as well as its zone size, porosity and permeability, and drilling speed (penetration rate). The obtained data can be used for the quantitative assessment of the potential severity of SWF hazards. The results indicate that overpressure of the SWF formation and its zone size have significant effects on SWF blowout. A 10% increase in the SWF formation overpressure can result in a more than 90% increase in the cumulative water blowout and a 150% increase in the sand blowout when a typical SWF sediment is drilled. Along with the conventional methods of well flow and pressure control, chemical plugging, and the application of multi-layer casing, water and sand blowouts can be effectively reduced by increasing the penetration rate. As such, increasing the penetration rate can be a useful measure for controlling SWF hazards during deepwater drilling.

The Hydraulic Mechanism in the Orbital Blowout Fracture Because of a High-Pressure Air Gun Injury.

PubMed

Kang, Seok Joo; Chung, Eui Han

2015-10-01

There are 2 predominant mechanisms that are used to explain the pathogenesis of orbital blowout fracture; these include hydraulic and buckling mechanisms. Still, however, its pathophysiology remains uncertain. To date, studies in this series have been conducted using dry skulls, cadavers, or animals. But few clinical studies have been conducted to examine whether the hydraulic mechanism is involved in the occurrence of pure orbital blowout fracture. The authors experienced a case of a 52-year-old man who had a pure medial blowout fracture after sustaining an eye injury because of a high-pressure air gun. Our case suggests that surgeons should be aware of the possibility that the hydraulic mechanism might be involved in the blowout fracture in patients presenting with complications, such as limitation of eye movement, diplopia, and enophthalmos.

Quantifying the flow rate of the Deepwater Horizon Macondo Well oil spill

NASA Astrophysics Data System (ADS)

Camilli, R.; Bowen, A.; Yoerger, D. R.; Whitcomb, L. L.; Techet, A. H.; Reddy, C. M.; Sylva, S.; Seewald, J.; di Iorio, D.; Whoi Flow Rate Measurement Group

2010-12-01

The Deepwater Horizon blowout in the Mississippi Canyon block 252 of the Gulf of Mexico created the largest recorded offshore oil spill. The well outflow’s multiple leak sources, turbulent multiphase flow, tendency for hydrate formation, and extreme source depth of 1500 m below the sea surface complicated the quantitative estimation of oil and gas leakage rates. We present methods and results from a U.S. Coast Guard sponsored flow assessment study of the Deepwater Horizon’s damaged blow out preventer and riser. This study utilized a remotely operated vehicle equipped with in-situ acoustic sensors (a Doppler sonar and an imaging multibeam sonar) and isobaric gas-tight fluid samplers to measure directly outflow from the damaged well. Findings from this study indicate oil release rates and total release volume estimates that corroborate estimates made by the federal government’s Flow Rate Technical Group using non-acoustic techniques. The acoustic survey methods reported here provides a means for estimating fluid flow rates in subsurface environments, and are potentially useful for a diverse range of oceanographic applications. Photograph of the Discoverer Enterprise burning natural gas collected from the Macondo well blowout preventer during flow measurement operations. Copyright Wood Hole Oceanographic Institution.

Gas-blowout control by water injection through relief wells: a theoretical analysis. [Injection of water into the formation through relief wells

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

Lehner, F.; Williamson, A.S.

1974-08-01

Koninklijke/Shell Exploratie en Produktie Laboratorium in The Netherlands suggests bringing a gas blowout under control by injecting water into the formation through relief wells. By avoiding direct contact between relief well and blowout well, this technique reduces the inflow of gas by creating sufficient back pressure in the formation itself. The mechanics of the technique are considered.

Orbital blowout fracture location in Japanese and Chinese patients.

PubMed

Sun, Michelle T; Wu, Wencan; Watanabe, Akihide; Kakizaki, Hirohiko; Chen, Ben; Ueda, Kosuke; Katori, Nobutada; Takahashi, Yasuhiro; Selva, Dinesh

2015-01-01

To characterize the location of orbital blowout fractures in Asian individuals. This was a retrospective review of 470 consecutive Asian patients with orbital blowout fractures who presented to four tertiary care hospitals in Japan and China. Computed tomography (CT) characterized the location and severity of fractures involving the medial wall, the orbital floor, and/or the maxilloethmoidal strut. A total of 475 orbital blowout fractures were identified. More than one fracture location was involved in 19% of all cases. The medial orbital wall was the most commonly involved location, presenting in 29 cases (61%), of which 204 (43%) were isolated medial blowout fractures. The orbital floor was the second most common location involved, present in 226 cases (48%) with 150 isolated orbital floor fractures (32%), while the maxilloethmoidal strut was involved in 45 cases (9%) with 30 of those being isolated strut fractures (6%). The majority of fractures (62%) were classified as moderately severe, whilst 14% were mild, and 24% were severe. Associated nasal fractures were present in 16% of the cases. Orbital blowout fractures in Japanese and Chinese individuals occur most commonly in the medial wall. This is in contrast to previous reports on white individuals, who tend to sustain fractures involving the orbital floor rather than the medial wall.

The cool component and the dichotomy, lateral expansion, and axial rotation of solar X-ray jets

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

Moore, Ronald L.; Sterling, Alphonse C.; Falconer, David A.

2013-06-01

We present results from a study of 54 polar X-ray jets that were observed in coronal X-ray movies from the X-ray Telescope on Hinode and had simultaneous coverage in movies of the cooler transition region (T ∼ 10{sup 5} K) taken in the He II 304 Å band of the Atmospheric Imaging Assembly (AIA) on Solar Dynamics Observatory. These dual observations verify the standard-jet/blowout-jet dichotomy of polar X-ray jets previously found primarily from XRT movies alone. In accord with models of blowout jets and standard jets, the AIA 304 Å movies show a cool (T ∼ 10{sup 5} K) componentmore » in nearly all blowout X-ray jets and in a small minority of standard X-ray jets, obvious lateral expansion in blowout X-ray jets but none in standard X-ray jets, and obvious axial rotation in both blowout X-ray jets and standard X-ray jets. In our sample, the number of turns of axial rotation in the cool-component standard X-ray jets is typical of that in the blowout X-ray jets, suggesting that the closed bipolar magnetic field in the jet base has substantial twist not only in all blowout X-ray jets but also in many standard X-ray jets. We point out that our results for the dichotomy, lateral expansion, and axial rotation of X-ray jets add credence to published speculation that type-II spicules are miniature analogs of X-ray jets, are generated by granule-size emerging bipoles, and thereby carry enough energy to power the corona and solar wind.« less

Delayed onset porous polyethylene implant-related inflammation after orbital blowout fracture repair: four case reports.

PubMed

Aryasit, Orapan; Ng, Danny S; Goh, Alice S C; Woo, Kyung In; Kim, Yoon-Duck

2016-07-07

Porous polyethylene implants are commonly used in orbital blowout fracture repair because of purported biocompatibility, durability, and low frequency of complications. Delayed inflammation related to porous polyethylene sheet implants is very rare and no case series of this condition have been reported. This is a retrospective review of clinical presentations, radiographic findings, histopathological findings, treatments, and outcomes of patients who developed delayed complications in orbital blowout fracture repair using porous polyethylene sheets. Four male patients were included with a mean age of 49 years (range 35-69 years). Blowout fracture repair was complicated with implant-related inflammation 10 months, 2 years, 3 years, and 8 years after surgery. Chronic and subacute orbital inflammatory signs were noted in two patients and acute fulminant orbital inflammation was found in two patients. Three patients developed peri-implant abscesses and one patient had a soft tissue mass around the implant. All patients underwent implant removal and two of these patients with paranasal sinusitis had sinus surgery. Histopathological findings revealed chronic inflammatory changes with fibrosis, and one patient had foreign body granuloma with culture positive Staphylococcus aureus. Delayed complications with porous polyethylene sheets used in orbital blowout fracture repair may occur many years following the initial surgery in immunocompetent patients. Low-grade or fulminant inflammation could complicate blowout fracture repair related with the implant.

PHYSICAL PARAMETERS OF STANDARD AND BLOWOUT JETS

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

Pucci, Stefano; Romoli, Marco; Poletto, Giannina

2013-10-10

The X-ray Telescope on board the Hinode mission revealed the occurrence, in polar coronal holes, of much more numerous jets than previously indicated by the Yohkoh/Soft X-ray Telescope. These plasma ejections can be of two types, depending on whether they fit the standard reconnection scenario for coronal jets or if they include a blowout-like eruption. In this work, we analyze two jets, one standard and one blowout, that have been observed by the Hinode and STEREO experiments. We aim to infer differences in the physical parameters that correspond to the different morphologies of the events. To this end, we adoptmore » spectroscopic techniques and determine the profiles of the plasma temperature, density, and outflow speed versus time and position along the jets. The blowout jet has a higher outflow speed, a marginally higher temperature, and is rooted in a stronger magnetic field region than the standard event. Our data provide evidence for recursively occurring reconnection episodes within both the standard and the blowout jet, pointing either to bursty reconnection or to reconnection occurring at different locations over the jet lifetimes. We make a crude estimate of the energy budget of the two jets and show how energy is partitioned among different forms. Also, we show that the magnetic energy that feeds the blowout jet is a factor of 10 higher than the magnetic energy that fuels the standard event.« less

Kill operation requires thorough analysis

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

Abel, L.W.

1995-05-15

Full control of a blowout well requires a properly designed post-capping kill operation because failures in regaining well control usually occur during the kill operation, not during capping. Capping (the installation of pressure control or diverter equipment on the wellhead) is generally very reliable in gaining control of a blowout well. The following techniques are some of the viable means of killing blowout wells once the capping assemblies are in place: direct shut in of the flow; bullheading; momentum kill; volumetric control for migration of fluids or lubrication after migration ceases; and dynamic kills (friction-based dynamic kills or mass flowmore » rate kills) The objective of most post-capping operations is to stop the flow and put the well under hydrostatic control. The means of killing a blowout once capping assemblies are in place should be chosen with care to avoid problems such as cratering, equipment failure, and underground blowouts. The particular circumstances and well integrity will dictate which kill method will be the most viable. Each of these five methods are explained.« less

Approach for assessing coastal vulnerability to oil spills for prevention and readiness using GIS and the Blowout and Spill Occurrence Model

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

Nelson, J. R.; Grubesic, T. H.; Sim, L.

Increasing interest in offshore hydrocarbon exploration has pushed the operational fronts associated with exploration efforts further offshore into deeper waters and more uncertain subsurface settings. This has become particularly common in the U.S. Gulf of Mexico. In this study we develop a spatial vulnerability approach and example assessment to support future spill prevention and improve future response readiness. This effort, which is part of a larger integrated assessment modeling spill prevention effort, incorporated economic and environmental data, and utilized a novel new oil spill simulation model from the U.S. Department of Energy’s National Energy Technology Laboratory, the Blowout and Spillmore » Occurrence Model (BLOSOM). Specifically, this study demonstrated a novel approach to evaluate potential impacts of hypothetical spill simulations at varying depths and locations in the northern Gulf of Mexico. The simulations are analyzed to assess spatial and temporal trends associated with the oil spill. The approach itself demonstrates how these data, tools and techniques can be used to evaluate potential spatial vulnerability of Gulf communities for various spill scenarios. Results of the hypothetical scenarios evaluated in this study suggest that under conditions like those simulated, a strong westward push by ocean currents and tides may increase the impacts of deep water spills along the Texas coastline, amplifying the vulnerability of communities on the local barrier islands. Ultimately, this approach can be used further to assess a range of conditions and scenarios to better understand potential risks and improve informed decision making for operators, responders, and stakeholders to support spill prevention as well as response readiness.« less

Approach for assessing coastal vulnerability to oil spills for prevention and readiness using GIS and the Blowout and Spill Occurrence Model

DOE PAGES

Nelson, J. R.; Grubesic, T. H.; Sim, L.; ...

2015-08-01

Increasing interest in offshore hydrocarbon exploration has pushed the operational fronts associated with exploration efforts further offshore into deeper waters and more uncertain subsurface settings. This has become particularly common in the U.S. Gulf of Mexico. In this study we develop a spatial vulnerability approach and example assessment to support future spill prevention and improve future response readiness. This effort, which is part of a larger integrated assessment modeling spill prevention effort, incorporated economic and environmental data, and utilized a novel new oil spill simulation model from the U.S. Department of Energy’s National Energy Technology Laboratory, the Blowout and Spillmore » Occurrence Model (BLOSOM). Specifically, this study demonstrated a novel approach to evaluate potential impacts of hypothetical spill simulations at varying depths and locations in the northern Gulf of Mexico. The simulations are analyzed to assess spatial and temporal trends associated with the oil spill. The approach itself demonstrates how these data, tools and techniques can be used to evaluate potential spatial vulnerability of Gulf communities for various spill scenarios. Results of the hypothetical scenarios evaluated in this study suggest that under conditions like those simulated, a strong westward push by ocean currents and tides may increase the impacts of deep water spills along the Texas coastline, amplifying the vulnerability of communities on the local barrier islands. Ultimately, this approach can be used further to assess a range of conditions and scenarios to better understand potential risks and improve informed decision making for operators, responders, and stakeholders to support spill prevention as well as response readiness.« less

A small-scale eruption leading to a blowout macrospicule jet in an on-disk coronal hole

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

Adams, Mitzi; Sterling, Alphonse C.; Moore, Ronald L.

2014-03-01

We examine the three-dimensional magnetic structure and dynamics of a solar EUV-macrospicule jet that occurred on 2011 February 27 in an on-disk coronal hole. The observations are from the Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) and the SDO Helioseismic and Magnetic Imager (HMI). The observations reveal that in this event, closed-field-carrying cool absorbing plasma, as in an erupting mini-filament, erupted and opened, forming a blowout jet. Contrary to some jet models, there was no substantial recently emerged, closed, bipolar-magnetic field in the base of the jet. Instead, over several hours, flux convergence and cancellation at the polarity inversionmore » line inside an evolved arcade in the base apparently destabilized the entire arcade, including its cool-plasma-carrying core field, to undergo a blowout eruption in the manner of many standard-sized, arcade-blowout eruptions that produce a flare and coronal mass ejection. Internal reconnection made bright 'flare' loops over the polarity inversion line inside the blowing-out arcade field, and external reconnection of the blowing-out arcade field with an ambient open field made longer and dimmer EUV loops on the outside of the blowing-out arcade. That the loops made by the external reconnection were much larger than the loops made by the internal reconnection makes this event a new variety of blowout jet, a variety not recognized in previous observations and models of blowout jets.« less

The use of time-series LIDAR to understand the role of foredune blowouts in coastal dune dynamics, Sefton, NW England.

NASA Astrophysics Data System (ADS)

O'Keeffe, Nicholas; Delgado-Fernandez, Irene; Aplin, Paul; Jackson, Derek; Marston, Christopher

2017-04-01

Coastal dunes are natural buffers against the threat of climate change-induced sea level rise. Their evolution is largely controlled by sediment exchanges between the geomorphic sub-units of the nearshore, beach, foredune and dune field. Coastlines characterised by multiple blowouts at the beach-dune interface may be more susceptible to coastline retreat through the enhanced landwards transport of beach and foredune sediment. This study, based in Sefton, north-west England, exploits an unprecedented temporal coverage of LIDAR surveys spanning 15 years (1999, 2008, 2010, 2013 and 2014). Established GIS techniques have been utilised to extract both the coastline (foredune toe) and the foredune crest from each LIDAR derived DTM (Digital Terrain Model). Migration of the foredune toe has been tracked over this period. Analysis of differentials between the height of the dune toe and dune crest have been used to locate the alongshore position of blowouts within the foredune. Dune sediment budgets have then been calculated for each DTM and analysis of the budgets conducted, with the coastline being compartmentalised alongshore, based on presence of blowouts within the foredune. Results indicate that sections of the coastline where blowouts are present within the foredune may be most vulnerable to coastline retreat. Temporal changes in the sediment budget within many of these sections also provides evidence that, if blowouts are present, coastline retreat continues to be a possibility even when the dune sediment budget remains positive.

Effect of Oxygen addition on altitude blowout and relight of an experimental combustor segment

NASA Technical Reports Server (NTRS)

Norgren, C. T.; Ingebo, R. D.

1974-01-01

The effect of oxygen addition on the low pressure altitude blowout limits of an experimental combustor segment was investigated. Data were obtained for two inlet-air temperatures, two inlet-airflow rates, and a constant fuel-air ratio of 0.020 with Jet A fuel. It was shown that the pressure at blowout could be reduced to correspond to an increase in altitude of 4.6 kilometers with oxygen flow rates of 8 to 16 percent by weight of the total fuel flow.

One-side riddled basin below and beyond the blowout bifurcation

NASA Astrophysics Data System (ADS)

Yang, H. L.

2000-10-01

In this Rapid Comunication we report a phenomenon of a one-side riddled basin where one side of the basin of attraction of an attractor on an invariant subspace (ISS) is globally riddled, while the other side is only locally riddled. This kind of basin appears due to the symmetry breaking with respect to the ISS. This one-side riddled basin can even persist beyond the blowout bifurcation, contrary to the previously reported riddled basins which exist only below the blowout transition. An experimental situation where this phenomenon can be expected is proposed.

Intelligent Engine Systems: Alternate Fuels Evaluation

NASA Technical Reports Server (NTRS)

Ballal, Dilip

2008-01-01

The performance and gaseous emissions were measured for a well-stirred reactor operating under lean conditions for two fuels: JP8 and a synthetic Fisher-Tropsch fuel over a range of equivalence ratios from 0.6 down to the lean blowout. The lean blowout characteristics were determined in LBO experiments at loading parameter values from 0.7 to 1.4. The lean blowout characteristics were then explored under higher loading conditions by simulating higher altitude operation with the use of nitrogen as a dilution gas for the air stream. The experiments showed that: (1) The lean blowout characteristics for the two fuels were close under both low loading and high loading conditions. (2) The combustion temperatures and observed combustion efficiencies were similar for the two fuels. (3) The gaseous emissions were similar for the two fuels and the differences in the H2O and CO2 emissions appear to be directly relatable to the C/H ratio for the fuels.

ON A CORONAL BLOWOUT JET: THE FIRST OBSERVATION OF A SIMULTANEOUSLY PRODUCED BUBBLE-LIKE CME AND A JET-LIKE CME IN A SOLAR EVENT

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

Shen Yuandeng; Liu Yu; Su Jiangtao

2012-02-01

The coronal blowout jet is a peculiar category among various jet phenomena, in which the sheared base arch, often carrying a small filament, experiences a miniature version of blowout eruption that produces large-scale coronal mass ejection (CME). In this paper, we report such a coronal blowout jet with high-resolution multi-wavelength and multi-angle observations taken from Solar Dynamics Observatory, Solar Terrestrial Relations Observatory, and Big Bear Solar Observatory. For the first time, we find that simultaneous bubble-like and jet-like CMEs were dynamically related to the blowout jet that showed cool and hot components next to each other. Our observational results indicatemore » that (1) the cool component resulted from the eruption of the filament contained within the jet's base arch, and it further caused the bubble-like CME; (2) the jet-like CME was associated with the hot component, which was the outward moving heated plasma generated by the reconnection of the base arch and its ambient open field lines. On the other hand, bifurcation of the jet's cool component was also observed, which resulted from the uncoupling of the erupting filament's two legs that were highly twisted at the very beginning. Based on these results, we propose a model to interpret the coronal blowout jet, in which the external reconnection not only produces the jet-like CME, but also leads to the rising of the filament. Subsequently, internal reconnection starts underneath the rising filament and thereby causes the bubble-like CME.« less

A Crashworthiness Analysis with Emphasis on the Fire Hazard: U.S. and Selected Foreign Turbine Aircraft Accidents, 1964-1974

DTIC Science & Technology

1976-07-01

1965 Summary, Pg. 11 21. 6/14/65, DC-8, , Santiago , Chile Left main landing gear brakes were locked on touchdown causing tire blowouts and a small fire... concentration of nine percent will prevent an explosion such as hat which occurred under similar ex- ternal fire test conditions in an tudnerted fuel tank. These...the inert concentration in the tanks was lost, providing more time for safe evacuation. Liquid nitrogen fuel tank inerting technology is presently

Was the extreme and wide-spread marine oil-snow sedimentation and flocculent accumulation (MOSSFA) event during the Deepwater Horizon blow-out unique?

PubMed

Vonk, Sophie M; Hollander, David J; Murk, AlberTinka J

2015-11-15

During the Deepwater Horizon blowout, thick layers of oiled material were deposited on the deep seafloor. This large scale benthic concentration of oil is suggested to have occurred via the process of Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA). This meta-analysis investigates whether MOSSFA occurred in other large oil spills and identifies the main drivers of oil sedimentation. MOSSFA was found to have occurred during the IXTOC I blowout and possibly during the Santa Barbara blowout. Unfortunately, benthic effects were not sufficiently studied for the 52 spills we reviewed. However, based on the current understanding of drivers involved, we conclude that MOSSFA and related benthic contamination may be widespread. We suggest to collect and analyze sediment cores at specific spill locations, as improved understanding of the MOSSFA process will allow better informed spill responses in the future, taking into account possible massive oil sedimentation and smothering of (deep) benthic ecosystems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stacked Deck: An Effective, School-Based Program for the Prevention of Problem Gambling

ERIC Educational Resources Information Center

Williams, Robert J.; Wood, Robert T.; Currie, Shawn R.

2010-01-01

School-based prevention programs are an important component of problem gambling prevention, but empirically effective programs are lacking. Stacked Deck is a set of 5-6 interactive lessons that teach about the history of gambling; the true odds and "house edge"; gambling fallacies; signs, risk factors, and causes of problem gambling; and…

Well blowout rates and consequences in California Oil and Gas District 4 from 1991 to 2005: Implications for geological storage of carbon dioxide

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

Jordan, Preston; Jordan, Preston D.; Benson, Sally M.

2008-05-15

Well blowout rates in oil fields undergoing thermally enhanced recovery (via steam injection) in California Oil and Gas District 4 from 1991 to 2005 were on the order of 1 per 1,000 well construction operations, 1 per 10,000 active wells per year, and 1 per 100,000 shut-in/idle and plugged/abandoned wells per year. This allows some initial inferences about leakage of CO2 via wells, which is considered perhaps the greatest leakage risk for geological storage of CO2. During the study period, 9% of the oil produced in the United States was from District 4, and 59% of this production was viamore » thermally enhanced recovery. There was only one possible blowout from an unknown or poorly located well, despite over a century of well drilling and production activities in the district. The blowout rate declined dramatically during the study period, most likely as a result of increasing experience, improved technology, and/or changes in safety culture. If so, this decline indicates the blowout rate in CO2-storage fields can be significantly minimized both initially and with increasing experience over time. Comparable studies should be conducted in other areas. These studies would be particularly valuable in regions with CO2-enhanced oil recovery (EOR) and natural gas storage.« less

Cooler and particulate separator for an off-gas stack

DOEpatents

Wright, G.T.

1991-04-08

This report describes an off-gas stack for a melter, furnace or reaction vessel comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes prevents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

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

Winter, J.R.; Keywood, S.S.

PTFE-based gaskets in chemical plant service typically fail in an extrusion mode, sometimes referred to as blowout. Test work previously published by Monsanto indicated that correctly installed PTFE-based gaskets have pressure performance far exceeding system pressure ratings. These results have since been confirmed by extensive testing at the Montreal based Ecole Polytechnique Tightness Testing and Research Laboratory (TTRL), funded by a consortium of gasket users and manufacturers. With the knowledge that properly installed gaskets can withstand system pressures in excess of 1,000 psig [6,894 kPa], failures at two chemical plants were re-examined. This analysis indicates that extrusion type failures canmore » be caused by excessive internal pressures, associated with sections of pipe having an external source of heat coincident with a blocked flow condition. This results in high system pressures which explain the extrusion type failures observed. The paper discusses details of individual failures and examines methods to prevent them. Other causes for extrusion failures are reviewed, with a recommendation that stronger gasket materials not be utilized to correct problems until it is verified that excessive pressure build-up is not the problem. Also summarized are the requirements for proper installation to achieve the potential blowout resistance found in these gaskets.« less

Covered stent graft for treatment of a pseudoaneurysm and carotid blowout syndrome

PubMed Central

Janjua, Nazli; Alkawi, Ammar; Georgiadis, Alexandros L.; Kirmani, Jawad F.; Qureshi, Adnan I.

2008-01-01

Background Carotid blowout syndrome with pseudoaneurysm, a rapidly progressive pathology, may present emergently with massive oral hemorrhage. Use of an endograft prosthesis offers a treatment strategy with salvation of the carotid artery. Case History: A 55 year old man with advanced squamous cell carcinoma of the head and neck presented with recurrent transoral hemorrhage, requiring endovascular treatment. Technical Report: Coil embolization was initially performed with little impact on the hemorrhage. A 7 x 40 mm Fluency® Plus covered stent (Bard Peripheral Vascular, Tempe, Arizona, USA) was placed and was supplemented by a second 8 x 40 mm Fluency Plus stent, with resulting cessation of active contrast extravasation. Discussion: The risks and benefits of various treatment options of carotid pseudoaneurysm with blowout are discussed including the use or omission of antiplatelet and anticoagulant regimens, with reference to previously reported cases. Conclusion: Tandem, overlapping covered stent placement in the common carotid artery is feasible and offers a treatment option for carotid blowout syndrome. Risks of aggravation of hemorrhage versus long-term thromboembolic events without antiplatelet therapy must be considered in cases of active ongoing hemorrhage. PMID:22518207

Can we treat CO₂ well blowouts like routine plumbing problems? A study of the incidence, impact, and perception of loss of well control

DOE PAGES

Porse, Sean L.; Wade, Sarah; Hovorka, Susan D.

2014-12-31

Risk communication literature suggests that for a number of reasons, the public may perceive a risk to be greater than indicated by its statistical probability. Public concern over risk can lead to significant and costly delays in project permitting and operations. Considering these theories, media coverage of CO₂-related well blowouts in 2013 gave rise to the questions: What is the risk of CO₂ well blowouts associated with CCUS through CO₂ EOR? What is the potential public perception of those risks? What information could be used to respond to public concern? To address these questions, this study aims to: 1) providemore » a framework for understanding the nature of onshore well blowouts, 2) quantify the incidence of such events for three specific geographic regions of Texas, 3) relate this data to CCUS and findings from other studies, and 4) explore the potential implications for public perception of this risk associated with CCUS projects. While quantifying answers to these questions proved to be challenging, the results from this study suggest that (1) the perceived risk of CO₂ well blowouts may exceed the statistical risk and (2) information that could be used to address this gap could be made more readily available to the greater benefit of industry and stakeholders who support the development of CCUS as an option for addressing anthropogenic CO₂ emissions. The study also suggests approaches to best conduct such data inquiries.« less

Magnetic Untwisting in Most Solar X-Ray Jets

NASA Technical Reports Server (NTRS)

Moore, Ronald; Sterling, Alphonse; Falconer, David; Robe, Dominic

2013-01-01

From 54 X-ray jets observed in the polar coronal holes by Hinode's X-Ray Telescope (XRT) during coverage in movies from Solar Dynamic Observatory's Atmospheric Imaging Assembly (AIA) taken in its He II 304 Å band at a cadence of 12 s, we have established a basic characteristic of solar X-ray jets: untwisting motion in the spire. In this presentation, we show the progression of few of these X-ray jets in XRT images and track their untwisting in AIA He II images. From their structure displayed in their XRT movies, 19 jets were evidently standard jets made by interchange reconnection of the magnetic-arcade base with ambient open field, 32 were evidently blowout jets made by blowout eruption of the base arcade, and 3 were of ambiguous form. As was anticipated from the >10,000 km span of the base arcade in most polar X-ray jets and from the disparity of standard jets and blowout jets in their magnetic production, few of the standard X-ray jets (3 of 19) but nearly all of the blowout X-ray jets (29 of 32) carried enough cool (T is approximately 105 K) plasma to be seen in their He II movies. In the 32 X-ray jets that showed a cool component, the He II movies show 10-100 km/s untwisting motions about the axis of the spire in all 3 standard jets and in 26 of the 29 blowout jets. Evidently, the open magnetic field in nearly all blowout X-ray jets and probably in most standard X-ray jets carries transient twist. This twist apparently relaxes by propagating out along the open field as a torsional wave. High-resolution spectrograms and Dopplergrams have shown that most Type-II spicules have torsional motions of 10-30 km/s. Our observation of similar torsional motion in X-ray jets strengthens the case for Type-II spicules being made in the same way as X-ray jets, by blowout eruption of a twisted magnetic arcade in the spicule base and/or by interchange reconnection of the twisted base arcade with the ambient open field. This work was funded by NASA's Heliophysics Division through its LWS TRT Program and its Hinode Project, and by NSF through its Research Experience for Undergraduates Program.

Bubbling and on-off intermittency in bailout embeddings.

PubMed

Cartwright, Julyan H E; Magnasco, Marcelo O; Piro, Oreste; Tuval, Idan

2003-07-01

We establish and investigate the conceptual connection between the dynamics of the bailout embedding of a Hamiltonian system and the dynamical regimes associated with the occurrence of bubbling and blowout bifurcations. The roles of the invariant manifold and the dynamics restricted to it, required in bubbling and blowout bifurcating systems, are played in the bailout embedding by the embedded Hamiltonian dynamical system. The Hamiltonian nature of the dynamics is precisely the distinctive feature of this instance of a bubbling or blowout bifurcation. The detachment of the embedding trajectories from the original ones can thus be thought of as transient on-off intermittency, and noise-induced avoidance of some regions of the embedded phase space can be recognized as Hamiltonian bubbling.

Hydrogen enrichment for low-emission jet combustion

NASA Technical Reports Server (NTRS)

Clayton, R. M.

1978-01-01

Simultaneous gaseous pollutant emission indexes (g pollutant/kg fuel) for a research combustor with inlet air at 120,900 N/sq m (11.9 atm) pressure and 727 K (849 F) temperature are as low as 1.0 for NOx and CO and 0.5 for unburned HC. Emissions data are presented for hydrogen/jet fuel (JP-5) mixes and for jet fuel only for premixed equivalence ratios from lean blowout to 0.65. Minimized emissions were achieved at an equivalence ratio of 0.38 using 10-12 mass percent hydrogen in the total fuel to depress the lean blowout limit. They were not achievable with jet fuel alone because of the onset of lean blowout at an equivalence ratio too high to reduce the NOx emission sufficiently.

Prediction of the blowout of jet diffusion flames in a coflowing stream of air

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

Karbasi, M.; Wierzba, I.

1995-12-31

The blowout limits of a lifted diffusion flame in a coflowing stream of air are estimated using a simple model for extinction, for a range of fuels, jet diameters and co-flowing stream velocities. The proposed model uses a parameter which relates to the ratio of a time associated with the mixing processes in a turbulent jet to a characteristic chemical time. The Kolmogorov microscale of time is used as time scale in this model. It is shown that turbulent diffusion flames are quenched by excessive turbulence for a critical value of this parameter. The predicted blowout velocity of diffusion flamesmore » obtained using this model is in good agreement with the available experimental data.« less

Orbital cellulitis: a rare complication after orbital blowout fracture.

PubMed

Ben Simon, Guy J; Bush, Steven; Selva, Dinesh; McNab, Alan A

2005-11-01

To report the incidence of orbital cellulitis after orbital blowout fracture. Retrospective, noncomparative, interventional case series. All patients with orbital cellulitis and a history of recent orbital fracture. A medical record review of clinical history, imaging studies, and surgical and treatment outcome was performed. Resolution of orbital cellulitis and surgical and imaging findings. Four patients (3 male; mean age, 30 years [range, 4.5-58]) were treated for orbital cellulitis complicating orbital fracture. All patients had evidence of paranasal sinusitis before or after the orbital injury, and 2 also reported forceful nose blowing after sustaining orbital trauma. Although 3 patients received prophylactic oral antibiotics after the fracture, this failed to prevent infection. Sinusitis commenced 1 to 2 weeks before and as late as 5 weeks after orbital injury. All patients were treated with IV antibiotics. Two developed an orbital abscess that required surgical drainage; 1 patient improved after an endonasal maxillary antrostomy. One patient improved on IV antibiotics alone and underwent fracture repair at a later stage. These 4 patients represent 0.8% of all cases of orbital fractures treated in the study period. Orbital cellulitis is a rare complication of orbital fracture, and seems to be more common when paranasal sinus infection preexists or occurs within several weeks of the injury. Oral antibiotics given after the orbital injury may not prevent orbital cellulitis or abscess formation. Surgery may be required to drain orbital abscess or in nonresolving cellulitis to drain the paranasal sinuses. Fracture repair, if indicated, should be delayed, particularly if an alloplastic implant is used.

Blowout Jets: Hinode X-Ray Jets that Don't Fit the Standard Model

NASA Technical Reports Server (NTRS)

Moore, Ronald L.; Cirtain, Jonathan W.; Sterling, Alphonse C.; Falconer, David A.

2010-01-01

Nearly half of all H-alpha macrospicules in polar coronal holes appear to be miniature filament eruptions. This suggests that there is a large class of X-ray jets in which the jet-base magnetic arcade undergoes a blowout eruption as in a CME, instead of remaining static as in most solar X-ray jets, the standard jets that fit the model advocated by Shibata. Along with a cartoon depicting the standard model, we present a cartoon depicting the signatures expected of blowout jets in coronal X-ray images. From Hinode/XRT movies and STEREO/EUVI snapshots in polar coronal holes, we present examples of (1) X-ray jets that fit the standard model, and (2) X-ray jets that do not fit the standard model but do have features appropriate for blowout jets. These features are (1) a flare arcade inside the jet-base arcade in addition to the small flare arcade (bright point) outside that standard jets have, (2) a filament of cool (T is approximately 80,000K) plasma that erupts from the core of the jetbase arcade, and (3) an extra jet strand that should not be made by the reconnection for standard jets but could be made by reconnection between the ambient unipolar open field and the opposite-polarity leg of the filament-carrying flux-rope core field of the erupting jet-base arcade. We therefore infer that these non-standard jets are blowout jets, jets made by miniature versions of the sheared-core-arcade eruptions that make CMEs

Eyebrow ptosis after blowout fracture indicates impairment of trigeminal proprioceptive evocation that induces reflex contraction of the frontalis muscle.

PubMed

Ban, Ryokuya; Matsuo, Kiyoshi; Ban, Midori; Yuzuriha, Shunsuke

2013-01-01

The mixed levator and frontalis muscles lack the interior muscle spindles normally required to induce involuntary contraction of their slow-twitch fibers. To involuntarily move the eyelid and eyebrow, voluntary contraction of the levator nonskeletal fast-twitch muscle fibers stretches the mechanoreceptors in Müller's muscle to evoke trigeminal proprioception, which then induces reflex contraction of the levator and frontalis skeletal slow-twitch muscle fibers. The trigeminal proprioceptive nerve has a long intraorbital course from the mechanoreceptors in Müller's muscle to the superior orbital fissure. Since external force to the globe may cause impairment of trigeminal proprioceptive evocation, we confirmed how unilateral blowout fracture due to a hydraulic mechanism affects ipsilateral eyebrow movement as compared with unilateral zygomatic fracture. In 16 unilateral blowout fracture patients, eyebrow heights were measured on noninjured and injured sides in primary and 60° upward gaze and statistically compared. Eyebrow heights were also measured in primary gaze in 24 unilateral zygomatic fracture patients and statistically compared. In the blowout fracture patients, eyebrow heights on the injured side were significantly smaller than on the noninjured side in both gaze. In the zygomatic fracture patients, eyebrow heights on the injured side were significantly larger than on the noninjured side in primary gaze. Since 60° upward gaze did not recover the eyebrow ptosis observed in primary gaze in blowout fracture patients, such ptosis indicated impairment of trigeminal proprioceptive evocation and the presence of a hydraulic mechanism that may require ophthalmic examination.

Eyebrow Ptosis After Blowout Fracture Indicates Impairment of Trigeminal Proprioceptive Evocation That Induces Reflex Contraction of the Frontalis Muscle

PubMed Central

Ban, Ryokuya; Matsuo, Kiyoshi; Ban, Midori; Yuzuriha, Shunsuke

2013-01-01

Objective: The mixed levator and frontalis muscles lack the interior muscle spindles normally required to induce involuntary contraction of their slow-twitch fibers. To involuntarily move the eyelid and eyebrow, voluntary contraction of the levator nonskeletal fast-twitch muscle fibers stretches the mechanoreceptors in Müller's muscle to evoke trigeminal proprioception, which then induces reflex contraction of the levator and frontalis skeletal slow-twitch muscle fibers. The trigeminal proprioceptive nerve has a long intraorbital course from the mechanoreceptors in Müller's muscle to the superior orbital fissure. Since external force to the globe may cause impairment of trigeminal proprioceptive evocation, we confirmed how unilateral blowout fracture due to a hydraulic mechanism affects ipsilateral eyebrow movement as compared with unilateral zygomatic fracture. Methods: In 16 unilateral blowout fracture patients, eyebrow heights were measured on noninjured and injured sides in primary and 60° upward gaze and statistically compared. Eyebrow heights were also measured in primary gaze in 24 unilateral zygomatic fracture patients and statistically compared. Results: In the blowout fracture patients, eyebrow heights on the injured side were significantly smaller than on the noninjured side in both gaze. In the zygomatic fracture patients, eyebrow heights on the injured side were significantly larger than on the noninjured side in primary gaze. Conclusion: Since 60° upward gaze did not recover the eyebrow ptosis observed in primary gaze in blowout fracture patients, such ptosis indicated impairment of trigeminal proprioceptive evocation and the presence of a hydraulic mechanism that may require ophthalmic examination. PMID:23814636

Short-term effects of oil ingestion on American kestrels (Falco sparverius).

PubMed

Pattee, O H; Franson, J C

1982-04-01

The Mexican Ixtoc oil well blowout resulted in extensive oil contamination along the Texas Gulf coast. This oil posed a potential hazard to migrating birds including the endangered peregrine falcon (Falco peregrinus). Laboratory tests with the American kestrel (Falco sparverius) indicated that the oil: water mixture gathered at the surface of the blowout site posed little acute hazard to falcons.

Prediction and validation of blowout limits of co-flowing jet diffusion flames -- effect of dilution

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

Karbasi, M.; Wierzba, I.

1996-10-01

The blowout limits of a co-flowing turbulent methane jet diffusion flame with addition of diluent in either jet fuel or surrounding air stream is studied both analytically and experimentally. Helium, nitrogen and carbon dioxide were employed as the diluents. Experiments indicated that an addition of diluents to the jet fuel or surrounding air stream decreased the stability limit of the jet diffusion flames. The strongest effect was observed with carbon dioxide as the diluent followed by nitrogen and then by helium. A model of extinction based on recognized criterion of the mixing time scale to characteristic combustion time scale ratiomore » using experimentally derived correlations is proposed. It is capable of predicting the large reduction of the jet blowout velocity due to a relatively small increase in the co-flow stream velocity along with an increase in the concentration of diluent in either the jet fuel or surrounding air stream. Experiments were carried out to validate the model. The predicted blowout velocities of turbulent jet diffusion flames obtained using this model are in good agreement with the corresponding experimental data.« less

An ergonomics approach model to prevention of occupational musculoskeletal injuries.

PubMed

Koltan, Altan

2009-01-01

The objective of this study was to prevent occupational musculoskeletal injuries. Our workers stacked boxes of ceramics weighing 10-27 kg, making low back pain common in our enterprise. In all the stacking stations, recommended weight limits (RWL) were separately calculated using the revised National Institute for Occupational Health lifting equation. Since the boxes weighed significantly more than the RWL, we developed a new ergonomic design that completely changed the stacking process. The load put on the workers' waist vertebrae in the new and the old stacking methods was compared to evaluate the success of the new ergonomic design, using Newton's third law of motion. Thanks to the new ergonomic design, the load on the workers' vertebrae decreased by 80%. Due to its simple technology and its very low cost compared to robots, the new ergonomic design can be commonly used in enterprises with repeated and constraining stacking.

Blowout brought under control in Gulf of Mexico

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

Not Available

1992-10-19

This paper reports that Greenhill Petroleum Corp., Houston, killed a well blowout Oct. 9 and began cleaning up oil spilled into Timbalier Bay off La Fourche Parish, La. Development well No. 250 in Timbalier Bay field blew out Sept. 29 while Blake Drilling and Workover Co., Belle Chasse, La., was trying to recomplete it in a deeper zone. Fire broke out as Boots and Coots Inc., Houston, was positioning control equipment at the wellhead. State and federal oil spill response officials estimated the uncontrolled flow of well No. 250 at 1,400 b/d of oil. Coast Guard officials on Oct. 8more » upgraded the blowout to a major spill, after deciding that at least 2,500 bbl of oil had gone into the water.« less

Modeling the key factors that could influence the diffusion of CO2 from a wellbore blowout in the Ordos Basin, China.

PubMed

Li, Qi; Shi, Hui; Yang, Duoxing; Wei, Xiaochen

2017-02-01

Carbon dioxide (CO 2 ) blowout from a wellbore is regarded as a potential environment risk of a CO 2 capture and storage (CCS) project. In this paper, an assumed blowout of a wellbore was examined for China's Shenhua CCS demonstration project. The significant factors that influenced the diffusion of CO 2 were identified by using a response surface method with the Box-Behnken experiment design. The numerical simulations showed that the mass emission rate of CO 2 from the source and the ambient wind speed have significant influence on the area of interest (the area of high CO 2 concentration above 30,000 ppm). There is a strong positive correlation between the mass emission rate and the area of interest, but there is a strong negative correlation between the ambient wind speed and the area of interest. Several other variables have very little influence on the area of interest, e.g., the temperature of CO 2 , ambient temperature, relative humidity, and stability class values. Due to the weather conditions at the Shenhua CCS demonstration site at the time of the modeled CO 2 blowout, the largest diffusion distance of CO 2 in the downwind direction did not exceed 200 m along the centerline. When the ambient wind speed is in the range of 0.1-2.0 m/s and the mass emission rate is in the range of 60-120 kg/s, the range of the diffusion of CO 2 is at the most dangerous level (i.e., almost all Grade Four marks in the risk matrix). Therefore, if the injection of CO 2 takes place in a region that has relatively low perennial wind speed, special attention should be paid to the formulation of pre-planned, emergency measures in case there is a leakage accident. The proposed risk matrix that classifies and grades blowout risks can be used as a reference for the development of appropriate regulations. This work may offer some indicators in developing risk profiles and emergency responses for CO 2 blowouts.

An Experimental Study of the Ionization of Low-Density Gas Flows by Induced Discharges

NASA Technical Reports Server (NTRS)

Barger, R. L.; Brooks, J. D.; Beasley, W. D.

1960-01-01

Induced discharges are advantageous for ionizing low-density flows in that they introduce no electrode contamination into the flow and they provide a relatively high degree of ionization with good coupling of power into the gas. In this investigation a 40-megacycle oscillator was used to produce and maintain induced discharges in argon and mercury-vapor flows. Methods for preventing blowout of the discharge were determined, and power measurements were made with an in-line wattmeter. Some results with damped oscillations pulsed at 1,000 pulses per second are also presented.

Use of fascia-peritoneum patch as a pledget for an infected aortic stump.

PubMed

Sarac, Timur P; Augustinos, Peter; Lyden, Sean; Ouriel, Kenneth

2003-12-01

Treatment of aortic prosthetic graft infections remains a challenge. One frequently encountered technical difficulty when removing an infected prosthetic aortic graft is how to close a short, friable remnant aortic stump. We present three case reports in which we used a layer of posterior rectus fascia-peritoneum to bolster oversewing a short infected aortic stump after removal of an infected aortic graft. All three patients underwent staged extra-anatomic axillary-to-femoral artery bypass procedures, with subsequent removal of the infected aortic graft as a second operation. Two of the three procedures were semi-elective, and one was done urgently because of a recurrent aortoenteric fistula. All three patients had less than 1 cm of remaining aortic neck below the renal arteries for closure. In each instance a segment of autogenous posterior rectus fascia-peritoneum was harvested and used as a circumferential pledget to bolster the anastomosis. No patient had stump blowout, and in no case was there computed tomography evidence of aneurysmal enlargement of the stump with follow-up of 12 and 24 months in two of the three survivors. Use of autogenous fascia-peritoneum is a durable and effective method to assist stump closure and prevent stump blowout after removal of infected aortic grafts.

Impact of an historic underground gas well blowout on the current methane chemistry in a shallow groundwater system

PubMed Central

Schout, Gilian; Hartog, Niels; Hassanizadeh, S. Majid; Griffioen, Jasper

2018-01-01

Blowouts present a small but genuine risk when drilling into the deep subsurface and can have an immediate and significant impact on the surrounding environment. Nevertheless, studies that document their long-term impact are scarce. In 1965, a catastrophic underground blowout occurred during the drilling of a gas well in The Netherlands, which led to the uncontrolled release of large amounts of natural gas from the reservoir to the surface. In this study, the remaining impact on methane chemistry in the overlying aquifers was investigated. Methane concentrations higher than 10 mg/L (n = 12) were all found to have δ13C-CH4 values larger than −30‰, typical of a thermogenic origin. Both δ13C-CH4 and δD-CH4 correspond to the isotopic composition of the gas reservoir. Based on analysis of local groundwater flow conditions, this methane is not a remnant but most likely the result of ongoing leakage from the reservoir as a result of the blowout. Progressive enrichment of both δ13C-CH4 and δD-CH4 is observed with increasing distance and decreasing methane concentrations. The calculated isotopic fractionation factors of εC = 3 and εD = 54 suggest anaerobic methane oxidation is partly responsible for the observed decrease in concentrations. Elevated dissolved iron and manganese concentrations at the fringe of the methane plume show that oxidation is primarily mediated by the reduction of iron and manganese oxides. Combined, the data reveal the long-term impact that underground gas well blowouts may have on groundwater chemistry, as well as the important role of anaerobic oxidation in controlling the fate of dissolved methane. PMID:29279383

A novel integrated approach for path following and directional stability control of road vehicles after a tire blow-out

NASA Astrophysics Data System (ADS)

Wang, Fei; Chen, Hong; Guo, Konghui; Cao, Dongpu

2017-09-01

The path following and directional stability are two crucial problems when a road vehicle experiences a tire blow-out or sudden tire failure. Considering the requirement of rapid road vehicle motion control during a tire blow-out, this article proposes a novel linearized decoupling control procedure with three design steps for a class of second order multi-input-multi-output non-affine system. The evaluating indicators for controller performance are presented and a performance related control parameter distribution map is obtained based on the stochastic algorithm which is an innovation for non-blind parameter adjustment in engineering implementation. The analysis on the robustness of the proposed integrated controller is also performed. The simulation studies for a range of driving conditions are conducted, to demonstrate the effectiveness of the proposed controller.

Bunch modulation in LWFA blowout regime

NASA Astrophysics Data System (ADS)

Vyskočil, Jiří; Klimo, Ondřej; Vieira, Jorge; Korn, Georg

2015-05-01

Laser wakefield acceleration (LWFA) is able to produce high quality electron bunches interesting for many applications ranging from coherent light sources to high energy physics. The blow-out regime of LWFA provides excellent accelerating structure able to maintain small transverse emittance and energy spread of the accelerating electron beam if combined with localised injection. A modulation of the back of a self-injected electron bunch in the blowout regime of Laser Wakefield Acceleration appears 3D Particle-in-Cell simulations with the code OSIRIS. The shape of the modulation is connected to the polarization of the driving laser pulse, although the wavelength of the modulation is longer than that of the pulse. Nevertheless a circularly polarized laser pulse leads to a corkscrew-like modulation, while in the case of linear polarization, the modulation lies in the polarization plane.

Short protection device for stack of electrolytic cells

DOEpatents

Katz, M.; Schroll, C.R.

1984-11-29

The present invention relates to a device for preventing the electrical shorting of a stack of electrolytic cells during an extended period of operation. The device has application to fuel cell and other electrolytic cell stacks operating in low or high temperature corrosive environments. It is of particular importance for use in a stack of fuel cells operating with molten metal carbonate electrolyte for the production of electric power. Also, the device may have application in similar technology involving stacks of electrolytic cells for electrolysis to decompose chemical compounds.

Betatron x-ray radiation from laser-plasma accelerators driven by femtosecond and picosecond laser systems

NASA Astrophysics Data System (ADS)

Albert, F.; Lemos, N.; Shaw, J. L.; King, P. M.; Pollock, B. B.; Goyon, C.; Schumaker, W.; Saunders, A. M.; Marsh, K. A.; Pak, A.; Ralph, J. E.; Martins, J. L.; Amorim, L. D.; Falcone, R. W.; Glenzer, S. H.; Moody, J. D.; Joshi, C.

2018-05-01

A comparative experimental study of betatron x-ray radiation from laser wakefield acceleration in the blowout and self-modulated regimes is presented. Our experiments use picosecond duration laser pulses up to 150 J (self-modulated regime) and 60 fs duration laser pulses up to 10 J (blowout regime), for plasmas with electronic densities on the order of 1019 cm-3. In the self-modulated regime, where betatron radiation has been very little studied compared to the blowout regime, electrons accelerated in the wake of the laser pulse are subject to both the longitudinal plasma and transverse laser electrical fields. As a result, their motion within the wake is relatively complex; consequently, the experimental and theoretical properties of the x-ray source based on self-modulation differ from the blowout regime of laser wakefield acceleration. In our experimental configuration, electrons accelerated up to about 250 MeV and betatron x-ray spectra with critical energies of about 10-20 keV and photon fluxes between 108 and 1010 photons/eV Sr are reported. Our experiments open the prospect of using betatron x-ray radiation for applications, and the source is competitive with current x-ray backlighting methods on multi-kilojoule laser systems.

Seed bank dynamics of blowout penstemon in relation to local patterns of sand movement on the Ferris Dunes, south-central Wyoming

Treesearch

Kassie L. Tilini; Susan E. Meyer; Phil S. Allen

2017-01-01

Plants restricted to active sand dunes possess traits that enable both survival in a harsh environment and local migration in response to a shifting habitat mosaic. We examined seed bank dynamics of Penstemon haydenii S. Watson (blowout penstemon) in relation to local sand movement. We measured within-year sand movement along a 400 m transect and examined plant density...

Breaking primary seed dormancy in Gibbens' beardtongue (Penstemon gibbensii) and blowout penstemon (Penstemon haydenii)

Treesearch

Kassie L. Tilini; Susan E. Meyer; Phil S. Allen

2016-01-01

This study established that chilling removes primary seed dormancy in 2 rare penstemons of the western US, Gibbens’ beardtongue (Penstemon gibbensii Dorn [Scrophulariaceae]) and blowout penstemon (Penstemon haydenii S. Watson). Wild-harvested seeds were subjected either to moist chilling at 2 to 4 °C (36-39 °F) for 0, 4, 8, 12, and 16 wk or to approximately 2 y of dry...

Real Time Navigation-Assisted Orbital Wall Reconstruction in Blowout Fractures.

PubMed

Shin, Ho Seong; Kim, Se Young; Cha, Han Gyu; Han, Ba Leun; Nam, Seung Min

2016-03-01

Limitation in performing restoration of orbital structures is the narrow, deep, and dark surgical field, which makes it difficult to view the operative site directly. To avoid perioperative complications from this limitation, the authors have evaluated the usefulness of computer-assisted navigation techniques in surgical treatment of blowout fracture. Total 37 patients (14 medial orbital wall fractures and 23 inferior orbital wall fractures) with facial deformities had surgical treatment under the guide of navigation system between September 2012 and January 2015. All 37 patients were treated successfully and safely with navigation-assisted surgery without any complications, including diplopia, retrobulbar hematoma, globe injury, implant migration, and blindness. Blowout fracture can be treated safely under guidance of a surgical navigation system. In orbital surgery, navigation-assisted technology could give rise to improvements in the functional and aesthetic outcome and checking the position of the instruments on the surgical site in real time, without injuring important anatomic structures.

Dynamic Blowout Risk Analysis Using Loss Functions.

PubMed

Abimbola, Majeed; Khan, Faisal

2018-02-01

Most risk analysis approaches are static; failing to capture evolving conditions. Blowout, the most feared accident during a drilling operation, is a complex and dynamic event. The traditional risk analysis methods are useful in the early design stage of drilling operation while falling short during evolving operational decision making. A new dynamic risk analysis approach is presented to capture evolving situations through dynamic probability and consequence models. The dynamic consequence models, the focus of this study, are developed in terms of loss functions. These models are subsequently integrated with the probability to estimate operational risk, providing a real-time risk analysis. The real-time evolving situation is considered dependent on the changing bottom-hole pressure as drilling progresses. The application of the methodology and models are demonstrated with a case study of an offshore drilling operation evolving to a blowout. © 2017 Society for Risk Analysis.

Development of a unified oil droplet size distribution model with application to surface breaking waves and subsea blowout releases considering dispersant effects.

PubMed

Li, Zhengkai; Spaulding, Malcolm; French McCay, Deborah; Crowley, Deborah; Payne, James R

2017-01-15

An oil droplet size model was developed for a variety of turbulent conditions based on non-dimensional analysis of disruptive and restorative forces, which is applicable to oil droplet formation under both surface breaking-wave and subsurface-blowout conditions, with or without dispersant application. This new model was calibrated and successfully validated with droplet size data obtained from controlled laboratory studies of dispersant-treated and non-treated oil in subsea dispersant tank tests and field surveys, including the Deep Spill experimental release and the Deepwater Horizon blowout oil spill. This model is an advancement over prior models, as it explicitly addresses the effects of the dispersed phase viscosity, resulting from dispersant application and constrains the maximum stable droplet size based on Rayleigh-Taylor instability that is invoked for a release from a large aperture. Copyright © 2016 Elsevier Ltd. All rights reserved.

Seismic and structural characterization of the fluid bypass system using 3D and partial stack seismic from passive margin: inside the plumbing system.

NASA Astrophysics Data System (ADS)

Iacopini, David; Maestrelli, Daniele; Jihad, Ali; Bond, Clare; Bonini, Marco

2017-04-01

In recent years enormous attention has been paid to the understanding of the process and mechanism controlling the gas seepage and more generally the fluid expulsion affecting the earth system from onshore to offshore environment. This is because of their demonstrated impact to our environment, climate change and during subsea drilling operation. Several example from active and paleo system has been so far characterized and proposed using subsurface exploration, geophysical and geochemical monitoring technology approaches with the aims to explore what trigger and drive the overpressure necessary maintain the fluid/gas/material expulsion and what are the structure that act as a gateway for gaseous fluid and unconsolidated rock. In this contribution we explore a series of fluid escape structure (ranging from seepage pipes to large blowout pipes structure of km length) using 3D and partial stack seismic data from two distinctive passive margin from the north sea (Loyal field, West Shetland) and the Equatorial Brazil (Ceara' Basin). We will focuses on the characterization of the plumbing system internal architecture and, for selected example, exploring the AVO response (using partial stack) of the internal fluid/unconsolidated rock. The detailed seismic mapping and seismic attributes analysis of the conduit system helped us to recover some detail from the signal response of the chimney internal structures. We observed: (1) small to medium seeps and pipes following structural or sedimentary discontinuities (2) large pipes (probably incipient mud volcanoes) and blowup structures propagating upward irrespective of pre-existing fault by hydraulic fracturing and assisted by the buoyancy of a fluidised and mobilised mud-hydrocarbon mixture. The reflector termination observed inside the main conduits, the distribution of stacked bright reflectors and the AVO analysis suggests an evolution of mechanisms (involving mixture of gas, fluid and probably mud) during pipe birth and development, cycling through classical fluid escape pipes evoking non-Darcy flow to Darcy flow exploiting surrounding permeable bodies (during low fluid recharge period). Limit and uncertainty of the seismic data imaging the internal structure are still controlled by illumination factor, the lateral and vertical resolution (Fresnel. Tuning thickness) and scattering/noise effect of seismic wave when they interact with the plumbing system.

Quantitative Risk Assessment (QRA) for an Underground Blowout Scenario in the Gulf of Mexico (GoM) Well

NASA Astrophysics Data System (ADS)

Tyagi, M.; Zulqarnain, M.

2017-12-01

Offshore oil and gas exploration and production operations, involve the use of some of the cutting edge and challenging technologies of the modern time. These technological complex operations involves the risk of major accidents as well, which have been demonstrated by disasters such as the explosion and fire on the UK production platform piper alpha, the Canadian semi-submersible drilling rig Ocean Ranger and the explosion and capsizing of Deepwater horizon rig in the Gulf of Mexico. By conducting Quantitative Risk Assessment (QRA), safety of various operations as well as their associated risks and significance during the entire life phase of an offshore project can be quantitatively estimated. In an underground blowout, the uncontrolled formation fluids from higher pressure formation may charge up shallower overlying low pressure formations or may migrate to sea floor. Consequences of such underground blowouts range from no visible damage at the surface to the complete loss of well, loss of drilling rig, seafloor subsidence or hydrocarbons discharged to the environment. These blowouts might go unnoticed until the over pressured sands, which are the result of charging from higher pressure reservoir due to an underground blowout. Further, engineering formulas used to estimate the fault permeability and thickness are very simple in nature and may add to uncertainty in the estimated parameters. In this study the potential of a deepwater underground blowout are assessed during drilling life phase of a well in Popeye-Genesis field reservoir in the Gulf of Mexico to estimate the time taken to charge a shallower zone to its leak-off test (LOT) value. Parametric simulation results for selected field case show that for relatively high permeability (k = 40mD) fault connecting a deep over-pressured zone to a shallower low-pressure zone of similar reservoir volumes, the time to recharge the shallower zone up to its threshold LOT value is about 135 years. If the ratio of the reservoir volumes for shallower to deeper zone is about 0.1, the recharging time significantly decreased to 24 years. Also, the hydrocarbons might possibly migrate through casing-wellbore annulus due to delamination fractures between cement interfaces with rock/casing and any other micro annulus gap not isolated by cement.

An experimental study of flame stability in a directly-fueled wall cavity with a supersonic free stream

NASA Astrophysics Data System (ADS)

Rasmussen, Chadwick Clifford

An extensive study of flame stability in a cavity-based fuel injector/flameholder has been performed. Flames were stabilized in cavities with two different aft wall configurations and length to depth ratios of 3 and 4. Fuel was injected directly into the cavity using two injector configurations. Fuel injected from the aft wall of the cavity entered directly into the recirculation zone and provided desirable performance near the lean blowout limit. At high fuel flowrates, the cavity became flooded with fuel and rich blowout occurred. When fuel was injected from the floor of the cavity, excess fuel was directed out of the cavity which allowed for flame stabilization at extremely high fuel flowrates; however, this phenomenon also resulted in suboptimal performance near the lean limit where the blowout point was less predictable. Images of planar laser-induced fluorescence (PLIF) of CH, OH, and formaldehyde give insight into the flameholding mechanisms. CH layers in the cavity are thin and continuous and show structure that is comparable to lifted jet flames, while broad CH zones are sometimes observed in the shear layer. OH PLIF images show that hot recirculated products are always present at the location of flame stabilization, whereas images of formaldehyde indicate that partial premixing takes place in the shear layer portion of the flame. Nonreacting measurements of the boundary layer and the free stream velocity profiles were obtained to provide necessary boundary conditions for computational modeling. Mean and instantaneous velocity profiles were determined for the nonreacting flow using particle image velocimetry (PIV). A correlation of the blowout points for a directly-fueled cavity in a supersonic flow was accomplished using a Damkohler number and an equivalence ratio based upon an effective air mass flowrate. The chemical time was formulated using a generic measure of the reaction rate, tauc ˜ alpha/ S2L , which was found to be adequate for correlating lean blowout data from methane, ethylene, acetylene, and hydrogen flames. Blowout data was collected at a number of conditions with varied pressure and temperature and Mach numbers of 2, 2.4, and 3. The effective air mass flowrate was determined using scaling laws for compressible mixing layers, which correctly incorporated the impact of compressibility on air entrainment.

Environmental legacy of an underground gas well blowout: long-term effects of gas and brine leakage on groundwater quality

NASA Astrophysics Data System (ADS)

Schout, Gilian; Hartog, Niels; Majid Hassanizadeh, S.; Griffioen, Jasper

2017-04-01

In 1965, a catastrophic underground blowout occurred during the drilling of a gas well in the village of Sleen, the Netherlands. The blowout led to the uncontrolled release of large amounts of natural gas and saline groundwater. Now, 50 years later, a number of nearby groundwater monitoring have been sampled to study the long term effects of this event on the groundwater composition of the overlying freshwater aquifers. The findings are used as an analogue for studying the potential adverse effects of hydraulic fracturing on groundwater quality. In total, 27 samples were taken and analysed for dissolved gas molecular and isotopic composition, major ion chemistry, water isotopes and stable chlorine isotope ratios. The resulting data show that concentrations of dissolved methane are still strongly elevated compared to background samples in a plume downstream of the blowout location. Isotopic data reveals the thermogenic nature of this plume; all samples with methane concentrations greater than 10 mg/l (n=12) had δC-CH4 values greater than -30‰ (VPDB), characteristic of thermogenic methane. The maximum distance at which thermogenic methane is observed is at approximately 500 meter downstream of the centre of the blowout. The progressive enrichment of both δ13C-CH4 and δ2D-CH4, that is observed with distance from the well and decreasing methane concentrations, presents strong evidence for the role of anaerobic methane oxidation (AOM) in limiting the spread of the dissolved methane plume. Low sulphate and increased Fe(II) and Mn(II) concentrations indeed suggest that multiple AOM pathways are involved in the natural attenuation of the dissolved methane plume. Chlorine concentrations were only elevated in a subset of wells in close proximity to the blowout location, indicating that the present-day effects of brine migration are minimal. Nevertheless, elevated Na/Cl ratio's in multiple wells reveal that freshening of the aquifer is still on-going. In summary, this research sheds new light on the long-term effects of natural gas and brine leakage on groundwater quality, which is considered one of the main environmental hazards related to hydraulic fracturing and unconventional gas production in general. Notably, it shows that the anaerobic oxidation of methane may play a major role in containing the effects of uncontrolled gas migration from reservoirs to shallow aquifers.

Advances in Turbulent Combustion Dynamics Simulations in Bluff-Body Stabilized Flames-Body Stabilized Flames

DTIC Science & Technology

2015-11-30

Master’s Thesis 3. DATES COVERED (From - To) 01 Nov 2015 – 30 Nov 2015 4. TITLE AND SUBTITLE Advances in Turbulent Combustion Dynamics Simulations...the three main aspects of bluff-body stabilized flames: stationary combustion , lean blow-out, and thermo-acoustic instabilities. For the cases of...stationary combustion and lean blow-out, an improved version of the Linear Eddy Model approach is used, while in the case of thermo-acoustic

More Macrospicule Jets in On-Disk Coronal Holes

NASA Astrophysics Data System (ADS)

Adams, Mitzi; Sterling, Alphonse; Moore, Ronald

2015-04-01

We examine the magnetic structure and dynamics of multiple jets found in coronal holes close to or at disk center. All data are from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO). We report on observations of about ten jets in an equatorial coronal hole spanning 2011 February 27 and 28. We show the evolution of these jets in AIA 193 Å, examine the magnetic field configuration and flux changes in the jet area, and discuss the probable trigger mechanism of these events. We reported on another jet in this same coronal hole on 2011 February 27, ~13:04 UT (Adams et al 2014, ApJ, 783: 11). That jet is a previously unrecognized variety of blowout jet, in which the base-edge bright point is a miniature filament-eruption flare arcade made by internal reconnection of the legs of the erupting field. In contrast, in the presently-accepted "standard" picture for blowout jets, the base-edge bright point is made by interchange reconnection of initially-closed erupting jet-base field with ambient open field. This poster presents further evidence of the production of the base-edge bright point in blowout jets by internal reconnection. Our observations suggest that most of the bigger and brighter EUV jets in coronal holes are blowout jets of the new-found variety.

Dichotomy of X-Ray Jets in Solar Coronal Holes

NASA Astrophysics Data System (ADS)

Robe, D. M.; Moore, R. L.; Falconer, D. A.

2012-12-01

It has been found that there are two different types of X-ray jets observed in the Sun's polar coronal holes: standard jets and blowout jets. A proposed model of this dichotomy is that a standard jet is produced by a burst of reconnection of the ambient magnetic field with the opposite-polarity leg of the base arcade. In contrast, it appears that a blowout jet is produced when the interior of the arcade has so much pent-up free magnetic energy in the form of shear and twist in the interior field that the external reconnection unleashes the interior field to erupt open. In this project, X-ray movies of the polar coronal holes taken by Hinode were searched for X-ray jets. Co-temporal movies taken by the Solar Dynamics Observatory in 304 Å emission from He II, showing solar plasma at temperatures around 80,000 K, were examined for whether the identified blowout jets carry much more He II plasma than the identified standard jets. It was found that though some jets identified as standard from the X-ray movies could be seen in the He II 304 Å movies, the blowout jets carried much more 80,000 K plasma than did most standard jets. This finding supports the proposed model for the morphology and development of the two types of jets.

Electron self-injection due to a plasma density downramp and gas ionization in a plasma wakefield accelerator in the blowout regime

NASA Astrophysics Data System (ADS)

Yi, S. A.; D'Avignon, E. C.; Khudik, V.; Shvets, G.

2010-11-01

We study self-injection into a plasma wakefield accelerator (PWFA) in the blowout regime analytically and through particle-in-cell (PIC) simulations. We propose a new injection mechanism into a plasma wakefield accelerator, where growth of the blowout region is enabled through a slow decrease in background plasma density along the direction of propagation. Deepening of the potential well due to this growth causes a reduction of electron Hamiltonian in the co-moving frame. This reduction depends on the shape of the blowout region, its growth rate, and impact parameter of the electron. When the reduction is greater than mc^2 [1,2], the electron becomes trapped inside the bubble. We demonstrate this effect using analytic expressions for the bubble potentials [3], and estimate plasma density gradients, and beam charge and size required for injection. We also apply the injection criterion to electron trapping through gas ionization. This work is supported by the US DOE grants DE-FG02-04ER41321 and DE-FG02-07ER54945. [1] S. Kalmykov, S.A. Yi, V. Khudik, and G. Shvets, Phys. Rev. Lett. 103, 135004 (2009). [2] S.A. Yi, V. Khudik, S. Kalmykov, and G. Shvets, Plasma Phys. Contr. Fus., in press. [3] W. Lu, C. Huang, M. Zhou, M. Tzoufras et al., Phys. Plasmas 13, 056709 (2006).

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

Porse, Sean L.; Wade, Sarah; Hovorka, Susan D.

Risk communication literature suggests that for a number of reasons, the public may perceive a risk to be greater than indicated by its statistical probability. Public concern over risk can lead to significant and costly delays in project permitting and operations. Considering these theories, media coverage of CO₂-related well blowouts in 2013 gave rise to the questions: What is the risk of CO₂ well blowouts associated with CCUS through CO₂ EOR? What is the potential public perception of those risks? What information could be used to respond to public concern? To address these questions, this study aims to: 1) providemore » a framework for understanding the nature of onshore well blowouts, 2) quantify the incidence of such events for three specific geographic regions of Texas, 3) relate this data to CCUS and findings from other studies, and 4) explore the potential implications for public perception of this risk associated with CCUS projects. While quantifying answers to these questions proved to be challenging, the results from this study suggest that (1) the perceived risk of CO₂ well blowouts may exceed the statistical risk and (2) information that could be used to address this gap could be made more readily available to the greater benefit of industry and stakeholders who support the development of CCUS as an option for addressing anthropogenic CO₂ emissions. The study also suggests approaches to best conduct such data inquiries.« less

More Macrospicule Jets in On-Disk Coronal Holes

NASA Technical Reports Server (NTRS)

Adams, M. L.; Sterling, A. C.; Moore, R. L.

2015-01-01

We examine the magnetic structure and dynamics of multiple jets found in coronal holes close to or on disk center. All data are from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO). We report on observations of about ten jets in an equatorial coronal hole spanning 2011 February 27 and 28. We show the evolution of these jets in AIA 193 A, examine the magnetic field configuration and flux changes in the jet area, and discuss the probable trigger mechanism of these events. We reported on another jet in this same coronal hole on 2011 February 27, (is) approximately 13:04 UT (Adams et al 2014, ApJ, 783: 11). That jet is a previously-unrecognized variety of blowout jet, in which the base-edge bright point is a miniature filament-eruption flare arcade made by internal reconnection of the legs of the erupting field. In contrast, in the presently-accepted 'standard' picture for blowout jets, the base-edge bright point is made by interchange reconnection of initially-closed erupting jet-base field with ambient open field. This poster presents further evidence of the production of the base-edge bright point in blowout jets by internal reconnection. Our observations suggest that most of the bigger and brighter EUV jets in coronal holes are blowout jets of the new-found variety.

Communications systems and methods for subsea processors

DOEpatents

Gutierrez, Jose; Pereira, Luis

2016-04-26

A subsea processor may be located near the seabed of a drilling site and used to coordinate operations of underwater drilling components. The subsea processor may be enclosed in a single interchangeable unit that fits a receptor on an underwater drilling component, such as a blow-out preventer (BOP). The subsea processor may issue commands to control the BOP and receive measurements from sensors located throughout the BOP. A shared communications bus may interconnect the subsea processor and underwater components and the subsea processor and a surface or onshore network. The shared communications bus may be operated according to a time division multiple access (TDMA) scheme.

Progress Update: Stack Project Complete

ScienceCinema

Cody, Tom

2017-12-12

Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

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

Hammeschlag, S.B.; Hughes, S.; O'Reilly, G.V.

Orbital blow-out fractures were experimentally created in eight human cadavers. Each orbit underwent conventional radiographic studies, complex motion tomography, and computed tomographic examinations. A comparison of the three modalities was made. Anatomical correlation was obtained by dissecting the orbits. The significance of medial-wall fractures and enophthalmos is discussed. Limitation of inferior rectus muscle mobility is thought to be a result of muscle kinking associated with orbital fat-pad prolapse at the fracture site, rather than muscle incarceration. Blow-out fractures should be evaluated by computed tomographic computer reformations in the oblique sagittal plane.

Dynamic stability of stacked disk type flywheels

NASA Astrophysics Data System (ADS)

Younger, F. C.

1981-04-01

A flywheel assembly formed from adhesively bonded stacked fiber composite disks was analyzed. The stiffness and rigidity of the assembly required to prevent uncontrolled growth in the deformations due to centrifugal force was determined. It is shown that stacked disk type flywheels become unstable when the speed exceeds a critical value. This critical value of speed depends upon the stiffness of the bonded attachments between the disks. It is found that elastomeric bonds do not provide adequate stiffness to insure dynamic stability for high speed stacked disk type flywheels.

Integrated fuel cell stack shunt current prevention arrangement

DOEpatents

Roche, Robert P.; Nowak, Michael P.

1992-01-01

A fuel cell stack includes a plurality of fuel cells juxtaposed with one another in the stack and each including a pair of plate-shaped anode and cathode electrodes that face one another, and a quantity of liquid electrolyte present at least between the electrodes. A separator plate is interposed between each two successive electrodes of adjacent ones of the fuel cells and is unified therewith into an integral separator plate. Each integral separator plate is provided with a circumferentially complete barrier that prevents flow of shunt currents onto and on an outer peripheral surface of the separator plate. This barrier consists of electrolyte-nonwettable barrier members that are accommodated, prior to the formation of the integral separator plate, in corresponding edge recesses situated at the interfaces between the electrodes and the separator plate proper. Each barrier member extends over the entire length of the associated marginal portion and is flush with the outer periphery of the integral separator plate. This barrier also prevents cell-to-cell migration of any electrolyte that may be present at the outer periphery of the integral separator plate while the latter is incorporated in the fuel cell stack.

Simulating pathways of subsurface oil in the Faroe-Shetland Channel using an ocean general circulation model.

PubMed

Main, C E; Yool, A; Holliday, N P; Popova, E E; Jones, D O B; Ruhl, H A

2017-01-15

Little is known about the fate of subsurface hydrocarbon plumes from deep-sea oil well blowouts and their effects on processes and communities. As deepwater drilling expands in the Faroe-Shetland Channel (FSC), oil well blowouts are a possibility, and the unusual ocean circulation of this region presents challenges to understanding possible subsurface oil pathways in the event of a spill. Here, an ocean general circulation model was used with a particle tracking algorithm to assess temporal variability of the oil-plume distribution from a deep-sea oil well blowout in the FSC. The drift of particles was first tracked for one year following release. Then, ambient model temperatures were used to simulate temperature-mediated biodegradation, truncating the trajectories of particles accordingly. Release depth of the modeled subsurface plumes affected both their direction of transport and distance travelled from their release location, and there was considerable interannual variability in transport. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Behavior and dynamics of bubble breakup in gas pipeline leaks and accidental subsea oil well blowouts.

PubMed

Wang, Binbin; Socolofsky, Scott A; Lai, Chris C K; Adams, E Eric; Boufadel, Michel C

2018-06-01

Subsea oil well blowouts and pipeline leaks release oil and gas to the environment through vigorous jets. Predicting the breakup of the released fluids in oil droplets and gas bubbles is critical to predict the fate of petroleum compounds in the marine water column. To predict the gas bubble size in oil well blowouts and pipeline leaks, we observed and quantified the flow behavior and breakup process of gas for a wide range of orifice diameters and flow rates. Flow behavior at the orifice transitions from pulsing flow to continuous discharge as the jet crosses the sonic point. Breakup dynamics transition from laminar to turbulent at a critical value of the Weber number. Very strong pure gas jets and most gas/liquid co-flowing jets exhibit atomization breakup. Bubble sizes in the atomization regime scale with the jet-to-plume transition length scale and follow -3/5 power-law scaling for a mixture Weber number. Copyright © 2018 Elsevier Ltd. All rights reserved.

Minifilament Eruption as the Source of a Blowout Jet, C-class Flare, and Type-III Radio Burst

NASA Astrophysics Data System (ADS)

Hong, Junchao; Jiang, Yunchun; Yang, Jiayan; Li, Haidong; Xu, Zhe

2017-01-01

We report a strong minifilament eruption associated with Geostationary Operational Environmental Satellite C1.6 flare and WIND type-III radio burst. The minifilament, which lies at the periphery of active region 12259, is detected by Hα images from the New Vacuum Solar Telescope. The minifilament undergoes a partial and then a full eruption. Simultaneously, two co-spatial jets are successively observed in extreme ultraviolet images from the Solar Dynamic Observatory. The first jet exhibits a typical fan-spine geometry, suggesting that the co-spatial minifilament is possibly embedded in magnetic fields with a fan-spine structure. However, the second jet displays blowout morphology when the entire minifilament erupts upward, leaving behind a hard X-ray emission source in the base. Differential emission measure analyses show that the eruptive region is heated up to about 4 MK during the fan-spine jet, while up to about 7 MK during the blowout jet. In particular, the blowout jet is accompanied by an interplanetary type-III radio burst observed by WIND/WAVES in the frequency range from above 10 to 0.1 MHz. Hence, the minifilament eruption is correlated with the interplanetary type-III radio burst for the first time. These results not only suggest that coronal jets can result from magnetic reconnection initiated by erupting minifilaments with open fields, but also shed light on the potential influence of minifilament eruption on interplanetary space.

The Measurement of the Sensory Recovery Period in Zygoma and Blow-Out Fractures with Neurometer Current Perception Threshold.

PubMed

Oh, Daemyung; Yun, Taebin; Kim, Junhyung; Choi, Jaehoon; Jeong, Woonhyeok; Chu, Hojun; Lee, Soyoung

2016-09-01

Facial hypoesthesia is one of the most troublesome complaints in the management of facial bone fractures. However, there is a lack of literature on facial sensory recovery after facial trauma. The purpose of this study was to evaluate the facial sensory recovery period for facial bone fractures using Neurometer. Sixty-three patients who underwent open reduction of zygomatic and blowout fractures between December 2013 and July 2015 were included in the study. The facial sensory status of the patients was repeatedly examined preoperatively and postoperatively by Neurometer current perception threshold (CPT) until the results were normalized. Among the 63 subjects, 30 patients had normal Neurometer results preoperatively and postoperatively. According to fracture types, 17 patients with blowout fracture had a median recovery period of 0.25 months. Twelve patients with zygomatic fracture had a median recovery period of 1.00 month. Four patients with both fracture types had a median recovery period of 0.625 months. The median recovery period of all 33 patients was 0.25 months. There was no statistically significant difference in the sensory recovery period between types and subgroups of zygomatic and blowout fractures. In addition, there was no statistically significant difference in the sensory recovery period according to Neurometer results and the patients' own subjective reports. Neurometer CPT is effective for evaluating and comparing preoperative and postoperative facial sensory status and evaluating the sensory recovery period in facial bone fracture patients.

MINIFILAMENT ERUPTION AS THE SOURCE OF A BLOWOUT JET, C-CLASS FLARE, AND TYPE-III RADIO BURST

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

Hong, Junchao; Jiang, Yunchun; Yang, Jiayan

We report a strong minifilament eruption associated with Geostationary Operational Environmental Satellite C1.6 flare and WIND type-III radio burst. The minifilament, which lies at the periphery of active region 12259, is detected by H α images from the New Vacuum Solar Telescope. The minifilament undergoes a partial and then a full eruption. Simultaneously, two co-spatial jets are successively observed in extreme ultraviolet images from the Solar Dynamic Observatory . The first jet exhibits a typical fan-spine geometry, suggesting that the co-spatial minifilament is possibly embedded in magnetic fields with a fan-spine structure. However, the second jet displays blowout morphology whenmore » the entire minifilament erupts upward, leaving behind a hard X-ray emission source in the base. Differential emission measure analyses show that the eruptive region is heated up to about 4 MK during the fan-spine jet, while up to about 7 MK during the blowout jet. In particular, the blowout jet is accompanied by an interplanetary type-III radio burst observed by WIND /WAVES in the frequency range from above 10 to 0.1 MHz. Hence, the minifilament eruption is correlated with the interplanetary type-III radio burst for the first time. These results not only suggest that coronal jets can result from magnetic reconnection initiated by erupting minifilaments with open fields, but also shed light on the potential influence of minifilament eruption on interplanetary space.« less

The Correlation between the Orbital Volume Ratio and Enophthalmos in Unoperated Blowout Fractures

PubMed Central

Choi, Su Hyun; Gu, Ja Hea

2016-01-01

Background Enophthalmos may not appear immediately after trauma due to periorbital swelling in a blowout fracture, and preoperative measurements of enophthalmos cannot be used as a reliable guideline. It is important to predict the eventual final extent of enophthalmos in order to determine whether to perform surgery, and there have been several attempts to predict the degree of late enophthalmos using preoperative orbital volume. The purpose of this study is to investigate the correlation between the orbital volume ratio (OVR) with final enophthalmos and the palpebral fissure, and to find the OVR that induced 2 mm of enophthalmos in unilateral unoperated blowout fractures. Methods We retrospectively reviewed the medical records of 38 patients and divided them into 3 groups, determined by the fracture location. The relationships between the OVR and both the degree of enophthalmos and the palpebral fissure ratio (PFR) were assessed and, in particular, the OVR that induced 2 mm of enophthalmos was sought. Results Enophthalmos increased in proportion to the OVR, and there was a highly significant correlation between the increase in the OVR and the degree of enophthalmos (P<0.05). On the other hand, there was no correlation between OVR and PFR (P>0.05). The OVR that induced 2-mm enophthalmos was 112.18%. Conclusions The final degree of enophthalmos can be estimated by the preoperative measurement of OVR. Preoperative measurements of OVR can be used as quantitative values to predict the final degree of enophthalmos in pure blowout fractures. PMID:27896181

The Correlation between the Orbital Volume Ratio and Enophthalmos in Unoperated Blowout Fractures.

PubMed

Choi, Su Hyun; Kang, Dong Hee; Gu, Ja Hea

2016-11-01

Enophthalmos may not appear immediately after trauma due to periorbital swelling in a blowout fracture, and preoperative measurements of enophthalmos cannot be used as a reliable guideline. It is important to predict the eventual final extent of enophthalmos in order to determine whether to perform surgery, and there have been several attempts to predict the degree of late enophthalmos using preoperative orbital volume. The purpose of this study is to investigate the correlation between the orbital volume ratio (OVR) with final enophthalmos and the palpebral fissure, and to find the OVR that induced 2 mm of enophthalmos in unilateral unoperated blowout fractures. We retrospectively reviewed the medical records of 38 patients and divided them into 3 groups, determined by the fracture location. The relationships between the OVR and both the degree of enophthalmos and the palpebral fissure ratio (PFR) were assessed and, in particular, the OVR that induced 2 mm of enophthalmos was sought. Enophthalmos increased in proportion to the OVR, and there was a highly significant correlation between the increase in the OVR and the degree of enophthalmos (P<0.05). On the other hand, there was no correlation between OVR and PFR (P>0.05). The OVR that induced 2-mm enophthalmos was 112.18%. The final degree of enophthalmos can be estimated by the preoperative measurement of OVR. Preoperative measurements of OVR can be used as quantitative values to predict the final degree of enophthalmos in pure blowout fractures.

Mercury Dispersion Modeling And Purge Ventilation Stack Height Determination For Tank 40H

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

Rivera-Giboyeaux, A.

2017-05-19

The SRNL Atmospheric Technologies Group performed an analysis for mercury emissions from H-Tank Farm - Tank 40 ventilation system exhaust in order to assess whether the Short Term Exposure Limit (STEL), or Threshold Limit Value (TLV) levels for mercury will be exceeded during bulk sludge slurry mixing and sludge removal operations. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was used as the main dispersion modelling tool for this analysis. The results indicated that a 45-foot stack is sufficient to raise the plume centerline from the Tank 40 release to prevent mercury exposure problems for any of the stackmore » discharge scenarios provided. However, a 42-foot stack at Tank 40 is sufficient to prevent mercury exposure concerns in all emission scenarios except the 50 mg/m 3 release. At a 42-foot stack height, values exceeding the exposure standards are only measured on receptors located above 34 feet.« less

Characterization of complexities in combustion instability in a lean premixed gas-turbine model combustor.

PubMed

Gotoda, Hiroshi; Amano, Masahito; Miyano, Takaya; Ikawa, Takuya; Maki, Koshiro; Tachibana, Shigeru

2012-12-01

We characterize complexities in combustion instability in a lean premixed gas-turbine model combustor by nonlinear time series analysis to evaluate permutation entropy, fractal dimensions, and short-term predictability. The dynamic behavior in combustion instability near lean blowout exhibits a self-affine structure and is ascribed to fractional Brownian motion. It undergoes chaos by the onset of combustion oscillations with slow amplitude modulation. Our results indicate that nonlinear time series analysis is capable of characterizing complexities in combustion instability close to lean blowout.

Cooler and particulate separator for an off-gas stack

DOEpatents

Wright, George T.

1992-01-01

An off-gas stack for a melter comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes pervents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

Blowout jets and impulsive eruptive flares in a bald-patch topology

NASA Astrophysics Data System (ADS)

Chandra, R.; Mandrini, C. H.; Schmieder, B.; Joshi, B.; Cristiani, G. D.; Cremades, H.; Pariat, E.; Nuevo, F. A.; Srivastava, A. K.; Uddin, W.

2017-02-01

Context. A subclass of broad extreme ultraviolet (EUV) and X-ray jets, called blowout jets, have become a topic of research since they could be the link between standard collimated jets and coronal mass ejections (CMEs). Aims: Our aim is to understand the origin of a series of broad jets, some of which are accompanied by flares and associated with narrow and jet-like CMEs. Methods: We analyze observations of a series of recurrent broad jets observed in AR 10484 on 21-24 October 2003. In particular, one of them occurred simultaneously with an M2.4 flare on 23 October at 02:41 UT (SOLA2003-10-23). Both events were observed by the ARIES Hα Solar Tower-Telescope, TRACE, SOHO, and RHESSI instruments. The flare was very impulsive and followed by a narrow CME. A local force-free model of AR 10484 is the basis to compute its topology. We find bald patches (BPs) at the flare site. This BP topology is present for at least two days before to events. Large-scale field lines, associated with the BPs, represent open loops. This is confirmed by a global potential free source surface (PFSS) model. Following the brightest leading edge of the Hα and EUV jet emission, we can temporarily associate these emissions with a narrow CME. Results: Considering their characteristics, the observed broad jets appear to be of the blowout class. As the most plausible scenario, we propose that magnetic reconnection could occur at the BP separatrices forced by the destabilization of a continuously reformed flux rope underlying them. The reconnection process could bring the cool flux-rope material into the reconnected open field lines driving the series of recurrent blowout jets and accompanying CMEs. Conclusions: Based on a model of the coronal field, we compute the AR 10484 topology at the location where flaring and blowout jets occurred from 21 to 24 October 2003. This topology can consistently explain the origin of these events. The movie associated to Fig. 1 is available at http://www.aanda.org

Differences in 1D electron plasma wake field acceleration in MeV versus GeV and linear versus blowout regimes

NASA Astrophysics Data System (ADS)

Tsiklauri, David

2018-03-01

In some laboratory and most astrophysical situations, plasma wake-field acceleration of electrons is one dimensional, i.e., variation transverse to the beam's motion can be ignored. Thus, one dimensional, particle-in-cell (PIC), fully electromagnetic simulations of electron plasma wake field acceleration are conducted in order to study the differences in electron plasma wake field acceleration in MeV versus GeV and linear versus blowout regimes. First, we show that caution needs to be taken when using fluid simulations, as PIC simulations prove that an approximation for an electron bunch not to evolve in time for a few hundred plasma periods only applies when it is sufficiently relativistic. This conclusion is true irrespective of the plasma temperature. We find that in the linear regime and GeV energies, the accelerating electric field generated by the plasma wake is similar to the linear and MeV regimes. However, because GeV energy driving bunch stays intact for a much longer time, the final acceleration energies are much larger in the GeV energies case. In the GeV energy range and blowout regime, the wake's accelerating electric field is much larger in amplitude compared with the linear case and also plasma wake geometrical size is much larger. Thus, the correct positioning of the trailing bunch is needed to achieve the efficient acceleration. For the considered case, optimally, there should be approximately (90-100)c/ωpe distance between the trailing and driving electron bunches in the GeV blowout regime.

Tracking the Hercules 265 marine gas well blowout in the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Romero, Isabel C.; Özgökmen, Tamay; Snyder, Susan; Schwing, Patrick; O'Malley, Bryan J.; Beron-Vera, Francisco J.; Olascoaga, Maria J.; Zhu, Ping; Ryan, Edward; Chen, Shuyi S.; Wetzel, Dana L.; Hollander, David; Murawski, Steven A.

2016-01-01

On 23 July 2013, a marine gas rig (Hercules 265) ignited in the northern Gulf of Mexico. The rig burned out of control for 2 days before being extinguished. We conducted a rapid-response sampling campaign near Hercules 265 after the fire to ascertain if sediments and fishes were polluted above earlier baseline levels. A surface drifter study confirmed that surface ocean water flowed to the southeast of the Hercules site, while the atmospheric plume generated by the blowout was in eastward direction. Sediment cores were collected to the SE of the rig at a distance of ˜0.2, 8, and 18 km using a multicorer, and demersal fishes were collected from ˜0.2 to 8 km SE of the rig using a longline (508 hooks). Recently deposited sediments document that only high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) concentrations decreased with increasing distance from the rig suggesting higher pyrogenic inputs associated with the blowout. A similar trend was observed in the foraminifera Haynesina germanica, an indicator species of pollution. In red snapper bile, only HMW PAH metabolites increased in 2013 nearly double those from 2012. Both surface sediments and fish bile analyses suggest that, in the aftermath of the blowout, increased concentration of pyrogenically derived hydrocarbons was transported and deposited in the environment. This study further emphasizes the need for an ocean observing system and coordinated rapid-response efforts from an array of scientific disciplines to effectively assess environmental impacts resulting from accidental releases of oil contaminants.

The Gulf of Mexico ecosystem, six years after the Macondo oil well blowout

NASA Astrophysics Data System (ADS)

Joye, Samantha B.; Bracco, Annalisa; Özgökmen, Tamay M.; Chanton, Jeffrey P.; Grosell, Martin; MacDonald, Ian R.; Cordes, Erik E.; Montoya, Joseph P.; Passow, Uta

2016-07-01

The Gulf of Mexico ecosystem is a hotspot for biological diversity and supports a number of industries, from tourism to fishery production to oil and gas exploration, that serve as the economic backbone of Gulf coast states. The Gulf is a natural hydrocarbon basin, rich with stores of oil and gas that lie in reservoirs deep beneath the seafloor. The natural seepage of hydrocarbons across the Gulf system is extensive and, thus, the system's biological components experience ephemeral, if not, frequent, hydrocarbon exposure. In contrast to natural seepage, which is diffuse and variable over space and time, the 2010 Macondo oil well blowout, represented an intense, focused hydrocarbon infusion to the Gulf's deepwaters. The Macondo blowout drove rapid shifts in microbial populations and activity, revealed unexpected phenomena, such as deepwater hydrocarbon plumes and marine "oil snow" sedimentation, and impacted the Gulf's pelagic and benthic ecosystems. Understanding the distribution and fate of Macondo oil was limited to some degree by an insufficient ability to predict the physical movement of water in the Gulf. In other words, the available physical oceanographic models lacked critical components. In the past six years, much has been learned about the physical oceanography of the Gulf, providing transformative knowledge that will improve the ability to predict the movement of water and the hydrocarbons they carry in future blowout scenarios. Similarly, much has been learned about the processing and fate of Macondo hydrocarbons. Here, we provide an overview of the distribution, fate and impacts of Macondo hydrocarbons and offer suggestions for future research to push the field of oil spill response research forward.

40 CFR 60.61 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... cement by either the wet or dry process. (b) Bypass means any system that prevents all or a portion of the kiln or clinker cooler exhaust gases from entering the main control device and ducts the gases... cooler emissions. (c) Bypass stack means the stack that vents exhaust gases to the atmosphere from the...

40 CFR 60.61 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... cement by either the wet or dry process. (b) Bypass means any system that prevents all or a portion of the kiln or clinker cooler exhaust gases from entering the main control device and ducts the gases... cooler emissions. (c) Bypass stack means the stack that vents exhaust gases to the atmosphere from the...

40 CFR 60.61 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... cement by either the wet or dry process. (b) Bypass means any system that prevents all or a portion of the kiln or clinker cooler exhaust gases from entering the main control device and ducts the gases... cooler emissions. (c) Bypass stack means the stack that vents exhaust gases to the atmosphere from the...

40 CFR 60.61 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... cement by either the wet or dry process. (b) Bypass means any system that prevents all or a portion of the kiln or clinker cooler exhaust gases from entering the main control device and ducts the gases... cooler emissions. (c) Bypass stack means the stack that vents exhaust gases to the atmosphere from the...

40 CFR 60.61 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... cement by either the wet or dry process. (b) Bypass means any system that prevents all or a portion of the kiln or clinker cooler exhaust gases from entering the main control device and ducts the gases... cooler emissions. (c) Bypass stack means the stack that vents exhaust gases to the atmosphere from the...

Transient flow combustion

NASA Technical Reports Server (NTRS)

Tacina, R. R.

1984-01-01

Non-steady combustion problems can result from engine sources such as accelerations, decelerations, nozzle adjustments, augmentor ignition, and air perturbations into and out of the compressor. Also non-steady combustion can be generated internally from combustion instability or self-induced oscillations. A premixed-prevaporized combustor would be particularly sensitive to flow transients because of its susceptability to flashback-autoignition and blowout. An experimental program, the Transient Flow Combustion Study is in progress to study the effects of air and fuel flow transients on a premixed-prevaporized combustor. Preliminary tests performed at an inlet air temperature of 600 K, a reference velocity of 30 m/s, and a pressure of 700 kPa. The airflow was reduced to 1/3 of its original value in a 40 ms ramp before flashback occurred. Ramping the airflow up has shown that blowout is more sensitive than flashback to flow transients. Blowout occurred with a 25 percent increase in airflow (at a constant fuel-air ratio) in a 20 ms ramp. Combustion resonance was found at some conditions and may be important in determining the effects of flow transients.

Hercules 265 rapid response: Immediate ecosystem impacts of a natural gas blowout incident

NASA Astrophysics Data System (ADS)

Weber, Sarah C.; Peterson, Leigha; Battles, Jessica J.; Roberts, Brian J.; Peterson, Richard N.; Hollander, David J.; Chanton, Jeffrey P.; Joye, Samantha B.; Montoya, Joseph P.

2016-07-01

In late July 2013, the Hercules 265 drilling rig in the Northern Gulf of Mexico experienced a catastrophic loss of control. Large quantities of natural gas spewed into the environment for 2 days before the well self-sealed through down-hole collapse below the seafloor. Ecosystem Impacts of Oil and Gas Inputs to the Gulf (ECOGIG) and collaborating Gulf of Mexico Research Initiative (GoMRI) consortia mounted a rapid response cruise to characterize the waters around the Hercules 265 rig, beginning just 4 days after the blowout. Our analysis showed an immediate microbial response to the elevated concentrations of methane in the water column, as evidenced by the drawdown of oxygen to hypoxic conditions, the incorporation of methane-derived carbon into particles, and measurable rates of methane-assimilation and nitrogen-fixation. Additionally, radium isotope measurements allowed us to constrain the timescale of bottom water exposure to the influence of the rig. A second sampling by the Center for Integrated Modeling and Analysis of Gulf Ecosystems (C-IMAGE) consortium indicated that the ecosystem had returned to near pre-blowout conditions within one month.

Combustor exhaust-emissions and blowout-limits with diesel number 2 and Jet A fuels utilizing air-atomizing and pressure-atomizing nozzles

NASA Technical Reports Server (NTRS)

Ingebo, R. D.; Norgren, C. T.

1975-01-01

The effect of fuel properties on exhaust emissions and blowout limits of a high-pressure combustor segment is evaluated using a splash-groove air-atomizing fuel injector and a pressure-atomizing simplex fuel nozzle to burn both diesel number 2 and Jet A fuels. Exhaust emissions and blowout data are obtained and compared on the basis of the aromatic content and volatility of the two fuels. Exhaust smoke number and emission indices for oxides of nitrogen, carbon monoxide, and unburned hydrocarbons are determined for comparison. As compared to the pressure-atomizing nozzle, the air-atomizing nozzle is found to reduce nitrogen oxides by 20%, smoke number by 30%, carbon monoxide by 70%, and unburned hydrocarbons by 50% when used with diesel number 2 fuel. The higher concentration of aromatics and lower volatility of diesel number 2 fuel as compared to Jet A fuel appears to have the most detrimental effect on exhaust emissions. Smoke number and unburned hydrocarbons are twice as high with diesel number 2 as with Jet A fuel.

Ocean Wave Energy Harvesting Devices

DTIC Science & Technology

2007-04-01

the magnet stack and the tubular wall of the generator and completely prevent the magnet from making direct contact to the tube wall even when the...the 3.1 second device. If no ferrofluid is present, as a long magnetic stack moves inside a tube with a small gap between the magnet surface and the...inside wall of the tube , a very slight deviation from the vertical position can cause the edge of the end of the magnet stack to touch the tube (Fig. 3

Sea-floor methane blow-out and global firestorm at the K-T boundary

USGS Publications Warehouse

Max, M.D.; Dillon, William P.; Nishimura, C.; Hurdle, B.G.

1999-01-01

A previously unsuspected source of fuel for the global firestorm recorded by soot in the Cretaceous-Tertiary impact layer may have resided in methane gas associated with gas hydrate in the end-Cretaceous seafloor. End-Cretaceous impact-generated shock and megawaves would have had the potential to initiate worldwide oceanic methane gas blow-outs from these deposits. The methane would likely have ignited and incompletely combusted. This large burst of methane would have been followed by longer-term methane release as a part of a positive thermal feedback in the disturbed ocean-atmosphere system.

The persistence of large-scale blowouts in largely vegetated coastal dune fields

NASA Astrophysics Data System (ADS)

Delgado-Fernandez, Irene; Smyth, Thomas; Jackson, Derek; Davidson-Arnott, Robin; Smith, Alexander

2016-04-01

Coastal dunes move through natural phases of stability and instability during their evolution, displaying various temporal and spatial patterns across the dune field. Recent observations, however, have shown exceptionally rapid rates of stability through increased vegetative growth. This progressive vegetation colonisation and consequent loss of bare sand on coastal dune systems has been noted worldwide. Percentage reductions in bare sand of as much as 80% within just a few decades can been seen in examples from South Africa, Canada and Brazil as well as coastal dune sites across NW Europe. Despite these dramatic trends towards dune stabilisation, it is not uncommon to find particular examples of large-scale active blowouts and parabolic dunes within largely vegetated coastal dunes. While turbulence and airflow dynamics within features such as blowouts and other dune forms has been studied in detail within recent years, there is a lack of knowledge about what maintains dune mobility at these specific points in otherwise largely stabilized dune fields. This work explores the particular example of the 'Devil's Hole' blowout, Sefton Dunes, NW England. Approximately 300 m long by 100 m wide, its basin is below the water-table which leads to frequent flooding. Sefton Dunes in general have seen a dramatic loss of bare sand since the 1940s. However, and coinciding with this period of dune stabilisation, the 'Devil's Hole' has not only remained active but also grown in size at a rate of 4.5 m year-1 along its main axis. An exploration of factors controlling the maintenance of open bare sand areas at this particular location is examined using a variety of techniques including Computational Fluid Dynamics (CFD) airflow modelling and in situ empirical measurements of (short-term experiments) of wind turbulence and sand transport. Field measurements of wind parameters and transport processes were collected over a 2 week period during October 2015. Twenty three 3D ultrasonic anemometers were deployed at 0.5 m elevations over a grid covering sections of the blowout walls, deflation basin and depositional lobe. A number of high resolution sand traps and wenglor sensors were co-located with anemometers in the walls and basin, and a terrestrial laser scanner was used to collect high-resolution topographic data both before and after the strongest transport event recorded during the study period. Preliminary results indicate significant transport differences in operation at each of the two blow out walls as well as complex interactions between turbulence, superficial moisture content and up-wind sediment sources. This study represents a comprehensive examination of both wind and sediment flux patterns at high spatial and temporal resolution inside a large trough blowout feature; and reveals insights into why such systems are maintained as erosional features for long time periods.

Filament Eruptions, Jets, and Space Weather

NASA Technical Reports Server (NTRS)

Moore, Ronald; Sterling, Alphonse; Robe, Nick; Falconer, David; Cirtain, Jonathan

2013-01-01

Previously, from chromospheric H alpha and coronal X-ray movies of the Sun's polar coronal holes, it was found that nearly all coronal jets (greater than 90%) are one or the other of two roughly equally common different kinds, different in how they erupt: standard jets and blowout jets (Yamauchi et al 2004, Apl, 605, 5ll: Moore et all 2010, Apj, 720, 757). Here, from inspection of SDO/AIA He II 304 A movies of 54 polar x-ray jets observed in Hinode/XRT movies, we report, as Moore et al (2010) anticipated, that (1) most standard x-ray jets (greater than 80%) show no ejected plasma that is cool enough (T is less than or approximately 10(exp 5K) to be seen in the He II 304 A movies; (2) nearly all blownout X-ray jets (greater than 90%) show obvious ejection of such cool plasma; (3) whereas when cool plasma is ejected in standard X-ray jets, it shows no lateral expansion, the cool plasma ejected in blowout X-ray jets shows strong lateral expansion; and (4) in many blowout X-ray jets, the cool plasma ejection displays the erupting-magnetic-rope form of clasic filament eruptions and is thereby seen to be a miniature filament eruption. The XRT movies also showed most blowout X-ray jets to be larger and brighter, and hence to apparently have more energy, than most standard X-ray jets. These observations (1) confirm the dichotomy of coronal jets, (2) agree with the Shibata model for standard jets, and (3) support the conclusion of Moore et al (2010) that in blowout jets the magnetic-arch base of the jet erupts in the manner of the much larger magnetic arcades in which the core field, the field rooted along the arcade's polarity inversion line, is sheared and twisted (sigmoid), often carries a cool-plasma filament, and erupts to blowout the arcade, producing a CME. From Hinode/SOT Ca II movies of the polar limb, Sterling et al (2010, ApJ, 714, L1) found that chromospheric Type-II spicules show a dichotomy of eruption dynamics similar to that found here for the cool-plasma component of coronal X-ray jets. This favors the idea that Type-II spicules are miniature counterparts of coronal X-ray jets. In Moore et al (2011, ApJ, 731, L18), we pointed out that if Type-II spicules are magnetic eruptions that work like coronal X-ray jets, they carry an area-averaged mechanical energy flux of approximately 7x10)(exp 5) erg cm(exp -2) s(exp-1) into the corona in the form of MHD waves and jet outflow, enough to power the heating of the global corona and solar wind. On this basis, from our observations of mini-filament eruptions in blowout X-ray jets, we infer that magnetic explosions of the type that have erupting filaments in them are the main engines of both (1) the steady solar wind and (2) the CMEs that produce the most severe space weather by blasting out through the corona and solar wind, making solar energetic particle storms, and bashing the Earth's magnetosphere. We conclude that in focusing on prominences and filament eruptions, Einar had his eye on the main bet for understanding what powers all space weather, both the extreme and the normal.

Flux rope breaking and formation of a rotating blowout jet

NASA Astrophysics Data System (ADS)

Joshi, Navin Chandra; Nishizuka, Naoto; Filippov, Boris; Magara, Tetsuya; Tlatov, Andrey G.

2018-05-01

We analysed a small flux rope eruption converted into a helical blowout jet in a fan-spine configuration using multiwavelength observations taken by Solar Dynamics Observatory, which occurred near the limb on 2016 January 9. In our study, first, we estimated the fan-spine magnetic configuration with the potential-field calculation and found a sinistral small filament inside it. The filament along with the flux rope erupted upwards and interacted with the surrounding fan-spine magnetic configuration, where the flux rope breaks in the middle section. We observed compact brightening, flare ribbons, and post-flare loops underneath the erupting filament. The northern section of the flux rope reconnected with the surrounding positive polarity, while the southern section straightened. Next, we observed the untwisting motion of the southern leg, which was transformed into a rotating helical blowout jet. The sign of the helicity of the mini-filament matches the one of the rotating jets. This is consistent with recent jet models presented by Adams et al. and Sterling et al. We focused on the fine thread structure of the rotating jet and traced three blobs with the speed of 60-120 km s- 1, while the radial speed of the jet is ˜400 km s- 1. The untwisting motion of the jet accelerated plasma upwards along the collimated outer spine field lines, and it finally evolved into a narrow coronal mass ejection at the height of ˜9Rsun. On the basis of detailed analysis, we discussed clear evidence of the scenario of the breaking of the flux rope and the formation of the helical blowout jet in the fan-spine magnetic configuration.

Detection and control of combustion instability based on the concept of dynamical system theory.

PubMed

Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

2014-02-01

We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

Detection and control of combustion instability based on the concept of dynamical system theory

NASA Astrophysics Data System (ADS)

Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

2014-02-01

We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

Plasma Wake-field Acceleration in the Blow-out Regime

NASA Astrophysics Data System (ADS)

Barov, Nikolai; Rosenzweig, James

1999-11-01

Recent experiments at Argonne National Laboratory, investigating the blow-out regime of the plasma wake-field accelerator, are discussed. These experiments achieved stable underdense (beam denser than the ambient plasma density) beam transport, and measured average acceleration of 25 MV/m, corresponding to peak wave fields of over 60 MVm. A comparison of the results to simulation is given, and the physics of the system is discussed. Potential for improvements in performance and achieved acceleration gradient, as well as accelerated beam quality are examined within the context of the next generation of experiments at the Fermilab Test Facility. The status of these experiments will be given.

Blowout Monitor

NASA Technical Reports Server (NTRS)

1994-01-01

C Language Integrated Production System (CLIPS), a NASA-developed software shell for developing expert systems, has been embedded in a PC-based expert system for training oil rig personnel in monitoring oil drilling. Oil drilling rigs if not properly maintained for possible blowouts pose hazards to human life, property and the environment may be destroyed. CLIPS is designed to permit the delivery of artificial intelligence on computer. A collection of rules is set up and, as facts become known, these rules are applied. In the Well Site Advisor, CLIPS provides the capability to accurately process, predict and interpret well data in a real time mode. CLIPS was provided to INTEQ by COSMIC.

Credit PSR. The interior of the grinder room appears as ...

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

Credit PSR. The interior of the grinder room appears as seen looking southeast (148°), showing the remaining grinder equipment in the building. Note the blow-out wall in the background, and the water sprinkler head positioned over the hopper. The hopper top is connected to the dust receiver in the adjacent room. The blow-out wall is constructed to relieve pressure easily should an explosion occur, thus minimizing damage to the rest of the building structure. The floor has a conductive coating which dissipates static electrical charges that might otherwise cause fires - Jet Propulsion Laboratory Edwards Facility, Oxidizer Grinder Building, Edwards Air Force Base, Boron, Kern County, CA

Light rare earth element depletion during Deepwater Horizon blowout methanotrophy.

PubMed

Shiller, A M; Chan, E W; Joung, D J; Redmond, M C; Kessler, J D

2017-09-04

Rare earth elements have generally not been thought to have a biological role. However, recent work has demonstrated that the light REEs (LREEs: La, Ce, Pr, and Nd) are essential for at least some methanotrophs, being co-factors in the XoxF type of methanol dehydrogenase (MDH). We show here that dissolved LREEs were significantly removed in a submerged plume of methane-rich water during the Deepwater Horizon (DWH) well blowout. Furthermore, incubation experiments conducted with naturally methane-enriched waters from hydrocarbon seeps in the vicinity of the DWH wellhead also showed LREE removal concurrent with methane consumption. Metagenomic sequencing of incubation samples revealed that LREE-containing MDHs were present. Our field and laboratory observations provide further insight into the biochemical pathways of methanotrophy during the DWH blowout. Additionally, our results are the first observations of direct biological alteration of REE distributions in oceanic systems. In view of the ubiquity of LREE-containing MDHs in oceanic systems, our results suggest that biological uptake of LREEs is an overlooked aspect of the oceanic geochemistry of this group of elements previously thought to be biologically inactive and an unresolved factor in the flux of methane, a potent greenhouse gas, from the ocean.

Blowout Surge due to Interaction between a Solar Filament and Coronal Loops

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

Li, Haidong; Jiang, Yunchun; Yang, Jiayan

2017-06-20

We present an observation of the interaction between a filament and the outer spine-like loops that produces a blowout surge within one footpoint of large-scale coronal loops on 2015 February 6. Based the observation of the AIA 304 and 94 Å, the activated filament is initially embedded below a dome of a fan-spine configuration. Due to the ascending motion, the erupting filament reconnects with the outer spine-like field. We note that the material in the filament blows out along the outer spine-like field to form the surge with a wider spire, and a two-ribbon flare appears at the site ofmore » the filament eruption. In this process, small bright blobs appear at the interaction region and stream up along the outer spine-like field and down along the eastern fan-like field. As a result, a leg of the filament becomes radial and the material in it erupts, while another leg forms the new closed loops. Our results confirm that the successive reconnection occurring between the erupting filament and the coronal loops may lead to a strong thermal/magnetic pressure imbalance, resulting in a blowout surge.« less

Shear Ram Verification Test Protocol (VTP) Best Practices

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

Lindley, Roy A.; Braun, Joseph C.

A blowout preventer (BOP) is a critical component used on subsea oil and gas wells during drilling, completion, and workover operations on the U. S. outer continental shelf (OCS). The purpose of the BOP is to seal oil and gas wells, and in the case of an emergency well-control event, to prevent the uncontrolled release of hydrocarbons. One of the most important components of the BOP is the hydraulically operated blind shear ram (BSR) that shears drilling-related components, such as drill pipes, casings, tubings, and wire-related tools that may have been placed in the well. In addition to shearing thesemore » components, the BSR must form a seal to keep hydrocarbons within the well bore, even when under the highest well-fluid pressures expected. The purpose of this document is for Argonne National Laboratory (ANL) to provide an independent view, based on current regulations, and best practices for testing and confirming the operability and suitability of BSRs under realistic (or actual) well conditions.« less

Review of flow rate estimates of the Deepwater Horizon oil spill.

PubMed

McNutt, Marcia K; Camilli, Rich; Crone, Timothy J; Guthrie, George D; Hsieh, Paul A; Ryerson, Thomas B; Savas, Omer; Shaffer, Frank

2012-12-11

The unprecedented nature of the Deepwater Horizon oil spill required the application of research methods to estimate the rate at which oil was escaping from the well in the deep sea, its disposition after it entered the ocean, and total reservoir depletion. Here, we review what advances were made in scientific understanding of quantification of flow rates during deep sea oil well blowouts. We assess the degree to which a consensus was reached on the flow rate of the well by comparing in situ observations of the leaking well with a time-dependent flow rate model derived from pressure readings taken after the Macondo well was shut in for the well integrity test. Model simulations also proved valuable for predicting the effect of partial deployment of the blowout preventer rams on flow rate. Taken together, the scientific analyses support flow rates in the range of ∼50,000-70,000 barrels/d, perhaps modestly decreasing over the duration of the oil spill, for a total release of ∼5.0 million barrels of oil, not accounting for BP's collection effort. By quantifying the amount of oil at different locations (wellhead, ocean surface, and atmosphere), we conclude that just over 2 million barrels of oil (after accounting for containment) and all of the released methane remained in the deep sea. By better understanding the fate of the hydrocarbons, the total discharge can be partitioned into separate components that pose threats to deep sea vs. coastal ecosystems, allowing responders in future events to scale their actions accordingly.

Review of flow rate estimates of the Deepwater Horizon oil spill

USGS Publications Warehouse

McNutt, Marcia K.; Camilli, Rich; Crone, Timothy J.; Guthrie, George D.; Hsieh, Paul A.; Ryerson, Thomas B.; Savas, Omer; Shaffer, Frank

2012-01-01

The unprecedented nature of the Deepwater Horizon oil spill required the application of research methods to estimate the rate at which oil was escaping from the well in the deep sea, its disposition after it entered the ocean, and total reservoir depletion. Here, we review what advances were made in scientific understanding of quantification of flow rates during deep sea oil well blowouts. We assess the degree to which a consensus was reached on the flow rate of the well by comparing in situ observations of the leaking well with a time-dependent flow rate model derived from pressure readings taken after the Macondo well was shut in for the well integrity test. Model simulations also proved valuable for predicting the effect of partial deployment of the blowout preventer rams on flow rate. Taken together, the scientific analyses support flow rates in the range of ~50,000–70,000 barrels/d, perhaps modestly decreasing over the duration of the oil spill, for a total release of ~5.0 million barrels of oil, not accounting for BP's collection effort. By quantifying the amount of oil at different locations (wellhead, ocean surface, and atmosphere), we conclude that just over 2 million barrels of oil (after accounting for containment) and all of the released methane remained in the deep sea. By better understanding the fate of the hydrocarbons, the total discharge can be partitioned into separate components that pose threats to deep sea vs. coastal ecosystems, allowing responders in future events to scale their actions accordingly.

Review of flow rate estimates of the Deepwater Horizon oil spill

PubMed Central

McNutt, Marcia K.; Camilli, Rich; Crone, Timothy J.; Guthrie, George D.; Hsieh, Paul A.; Ryerson, Thomas B.; Savas, Omer; Shaffer, Frank

2012-01-01

The unprecedented nature of the Deepwater Horizon oil spill required the application of research methods to estimate the rate at which oil was escaping from the well in the deep sea, its disposition after it entered the ocean, and total reservoir depletion. Here, we review what advances were made in scientific understanding of quantification of flow rates during deep sea oil well blowouts. We assess the degree to which a consensus was reached on the flow rate of the well by comparing in situ observations of the leaking well with a time-dependent flow rate model derived from pressure readings taken after the Macondo well was shut in for the well integrity test. Model simulations also proved valuable for predicting the effect of partial deployment of the blowout preventer rams on flow rate. Taken together, the scientific analyses support flow rates in the range of ∼50,000–70,000 barrels/d, perhaps modestly decreasing over the duration of the oil spill, for a total release of ∼5.0 million barrels of oil, not accounting for BP's collection effort. By quantifying the amount of oil at different locations (wellhead, ocean surface, and atmosphere), we conclude that just over 2 million barrels of oil (after accounting for containment) and all of the released methane remained in the deep sea. By better understanding the fate of the hydrocarbons, the total discharge can be partitioned into separate components that pose threats to deep sea vs. coastal ecosystems, allowing responders in future events to scale their actions accordingly. PMID:22187459

Multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

DOEpatents

Farahmandi, C. J.; Dispennette, J. M.; Blank, E.; Kolb, A. C.

1999-05-25

A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator sleeve is inserted over the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH[sub 3]CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals. 32 figs.

Method of making a multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

DOEpatents

Farahmandi, C. Joseph; Dispennette, John M.; Blank, Edward; Kolb, Alan C.

2002-09-17

A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator is positioned against the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH.sub.3 CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals.

Multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

DOEpatents

Farahmandi, C Joseph [San Diego, CA; Dispennette, John M [Oceanside, CA; Blank, Edward [San Diego, CA; Kolb, Alan C [Rancho Santa Fe, CA

1999-05-25

A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator sleeve is inserted over the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH.sub.3 CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals.

Multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

DOEpatents

Farahmandi, C. Joseph; Dispennette, John M.; Blank, Edward; Kolb, Alan C.

1999-01-19

A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator sleeve is inserted over the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH.sub.3 CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals.

Multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

DOEpatents

Farahmandi, C.J.; Dispennette, J.M.; Blank, E.; Kolb, A.C.

1999-01-19

A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator sleeve is inserted over the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH{sub 3}CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals. 32 figs.

Method of making a multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

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

Farahmandi, C. Joseph; Dispennette, John M.; Blank, Edward

A method of making a double layer capacitior includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator is positioned against the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodesmore » are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH.sub.3 CN). In one embodiment, the two arts of the capacitor case are conductive and function as the capacitor terminals.« less

40 CFR 52.875 - Original identification of plan section.

Code of Federal Regulations, 2014 CFR

2014-07-01

... applicable to stationary sources subject to prevention of significant deterioration (PSD) permit requirements... interim stack height policy for each PSD permit issued until such time as EPA revises its general stack... submitted rule revisions to K.A.R. 28-19-17, the PSD rule; to K.A.R. 28-19-19, the CEM rule; and to K.A.R...

40 CFR 52.875 - Original identification of plan section.

Code of Federal Regulations, 2012 CFR

2012-07-01

... applicable to stationary sources subject to prevention of significant deterioration (PSD) permit requirements... interim stack height policy for each PSD permit issued until such time as EPA revises its general stack... submitted rule revisions to K.A.R. 28-19-17, the PSD rule; to K.A.R. 28-19-19, the CEM rule; and to K.A.R...

40 CFR 52.875 - Original identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

... applicable to stationary sources subject to prevention of significant deterioration (PSD) permit requirements... interim stack height policy for each PSD permit issued until such time as EPA revises its general stack... submitted rule revisions to K.A.R. 28-19-17, the PSD rule; to K.A.R. 28-19-19, the CEM rule; and to K.A.R...

40 CFR 52.875 - Original identification of plan section.

Code of Federal Regulations, 2011 CFR

2011-07-01

... applicable to stationary sources subject to prevention of significant deterioration (PSD) permit requirements... interim stack height policy for each PSD permit issued until such time as EPA revises its general stack... submitted rule revisions to K.A.R. 28-19-17, the PSD rule; to K.A.R. 28-19-19, the CEM rule; and to K.A.R...

Iridium Interfacial Stack (IRIS)

NASA Technical Reports Server (NTRS)

Spry, David James (Inventor)

2015-01-01

An iridium interfacial stack ("IrIS") and a method for producing the same are provided. The IrIS may include ordered layers of TaSi.sub.2, platinum, iridium, and platinum, and may be placed on top of a titanium layer and a silicon carbide layer. The IrIS may prevent, reduce, or mitigate against diffusion of elements such as oxygen, platinum, and gold through at least some of its layers.

Interaction of hydraulic and buckling mechanisms in blowout fractures.

PubMed

Nagasao, Tomohisa; Miyamoto, Junpei; Jiang, Hua; Tamaki, Tamotsu; Kaneko, Tsuyoshi

2010-04-01

The etiology of blowout fractures is generally attributed to 2 mechanisms--increase in the pressure of the orbital contents (the hydraulic mechanism) and direct transmission of impacts on the orbital walls (the buckling mechanism). The present study aims to elucidate whether or not an interaction exists between these 2 mechanisms. We performed a simulation experiment using 10 Computer-Aided-Design skull models. We applied destructive energy to the orbits of the 10 models in 3 different ways. First, to simulate pure hydraulic mechanism, energy was applied solely on the internal walls of the orbit. Second, to simulate pure buckling mechanism, energy was applied solely on the inferior rim of the orbit. Third, to simulate the combined effect of the hydraulic and buckling mechanisms, energy was applied both on the internal wall of the orbit and inferior rim of the orbit. After applying the energy, we calculated the areas of the regions where fracture occurred in the models. Thereafter, we compared the areas among the 3 energy application patterns. When the hydraulic and buckling mechanisms work simultaneously, fracture occurs on wider areas of the orbital walls than when each of these mechanisms works separately. The hydraulic and buckling mechanisms interact, enhancing each other's effect. This information should be taken into consideration when we examine patients in whom blowout fracture is suspected.

News from the "blowout", a man-made methane pockmark in the North Sea: chemosynthetic communities and microbial methane oxidation

NASA Astrophysics Data System (ADS)

Steinle, Lea I.; Wilfert, Philipp; Schmidt, Mark; Bryant, Lee; Haeckel, Matthias; Lehmann, Moritz F.; Linke, Peter; Sommer, Stefan; Treude, Tina; Niemann, Helge

2013-04-01

The accidental penetration of a base-Quaternary shallow gas pocket by a drilling rig in 1990 caused a "blowout" in the British sector of the North Sea (57°55.29' N, 01°37.86' E). Large quantities of methane have been seeping out of this man-made pockmark ever since. As the onset of gas seepage is well constrained, this site can be used as a natural laboratory to gain information on the development of methane oxidizing microbial communities at cold seeps. During an expedition with the R/V Celtic Explorer in July and August 2012, we collected sediments by video-guided push-coring with an ROV (Kiel 6000) along a gradient from inside the crater (close to where a jet of methane bubbles enters the water column) outwards. We also sampled the water column in a grid above the blowout at three different depths. In this presentation, we provide evidence for the establishment of methanotrophic communities in the sediment (AOM communities) on a time scale of decades. Furthermore, we will report data on methane concentrations and anaerobic methane oxidation rates in the sediment. Finally, we will also discuss the spatial distribution of methane and aerobic methane oxidation rates in the water column.

Lean blowout limits of a gas turbine combustor operated with aviation fuel and methane

NASA Astrophysics Data System (ADS)

Xiao, Wei; Huang, Yong

2016-05-01

Lean blowout (LBO) limits is critical to the operational performance of combustion systems in propulsion and power generation. The swirl cup plays an important role in flame stability and has been widely used in aviation engines. Therefore, the effects of swirl cup geometry and flow dynamics on LBO limits are significant. An experiment was conducted for studying the lean blowout limits of a single dome rectangular model combustor with swirl cups. Three types of swirl cup (dual-axial swirl cup, axial-radial swirl cup, dual-radial swirl cup) were employed in the experiment which was operated with aviation fuel (Jet A-1) and methane under the idle condition. Experimental results showed that, with using both Jet A-1 and methane, the LBO limits increase with the air flow of primary swirler for dual-radial swirl cup, while LBO limits decrease with the air flow of primary swirler for dual-axial swirl cup. In addition, LBO limits increase with the swirl intensity for three swirl cups. The experimental results also showed that the flow dynamics instead of atomization poses a significant influence on LBO limits. An improved semi-empirical correlation of experimental data was derived to predict the LBO limits for gas turbine combustors.

Combustor exhaust-emissions and blowout-limits with diesel number 2 and jet A fuels utilizing air-atomizing and pressure atomizing nozzles

NASA Technical Reports Server (NTRS)

Ingebo, R. D.; Norgren, C. T.

1975-01-01

Experimental tests with diesel number 2 and Jet A fuels were conducted in a combustor segment to obtain comparative data on exhaust emissions and blowout limits. An air-atomizing nozzle was used to inject the fuels. Tests were also made with diesel number 2 fuel using a pressure-atomizing nozzle to determine the effectiveness of the air-atomizing nozzle in reducing exhaust emissions. Test conditions included fuel-air ratios of 0.008 to 0.018, inlet-air total pressures and temperatures of 41 to 203 newtons per square centimeter and 477 to 811 K, respectively, and a reference velocity of 21.3 meters per second. Smoke number and unburned hydrocarbons were twice as high with diesel number 2 as with Jet A fuel. This was attributed to diesel number 2 having a higher concentration of aromatics and lower volatility than Jet A fuel. Oxides of nitrogen, carbon monoxide, and blowout limits were approximately the same for the two fuels. The air-atomizing nozzle, as compared with the pressure-atomizing nozzle, reduced oxides-of-nitrogen by 20 percent, smoke number by 30 percent, carbon monoxide by 70 percent, and unburned hydrocarbons by 50 percent when used with diesel number 2 fuel.

Altitude-Test-Chamber Investigation of a Solar Afterburner on the 24C Engine I - Operational Characteristics and Altitude Limits

NASA Technical Reports Server (NTRS)

1948-01-01

An altitude-test-chamber investigation was conducted to determine the operational characteristics and altitude blow-out limits of a Solar afterburner in a 24C engine. At rated engine speed and maximum permissible turbine-discharge temperature, the altitude limit as determined by combustion blow-out occurred as a band of unstable operation of about 8000 feet altitude in width with maximum altitude limits from 32,000 feet at a Mach number of 0.3 to about 42,000 feet at a Mach number of 1.0. The maximum fuel-air ratio of the afterburner, as limited by maximum permissible turbine-discharge gas temperatures at rated engine speed, varied between 0.0295 and 0.0380 over a range of flight Mach numbers from 0.25 to 1.0 and at altitudes of 20,000 and 30,000 feet. Over this range of operating conditions, the fuel-air ratio at which lean blow-out occurred was from 10 to 19 percent below these maximum fuel-air ratios. Combustion was very smooth and uniform during operation; however, ignition of the burner was very difficult throughout the investigation. A failure of the flame holder after 12 hours and 15 minutes of afterburner operation resulted in termination of the investigation.

The threats from oil spills: now, then, and in the future.

PubMed

Jernelöv, Arne

2010-01-01

The ongoing oil spill from the blown-out well by the name of Macondo, drilled by the ill-fated rig Deepwater Horizon, has many features in common with another blowout in the Mexican Gulf that happened three decades ago. Then the oil gushed out from the Ixtoc I well drilled by the Sedco 135-F semi-submersible rig. In the years between these catastrophes, the source and nature of oil spills have undergone large changes. Huge spills from tankers that ran aground or collided used to be what caught the headlines and caused large ecological damage. The number and size of such accidental spills have decreased significantly. Instead, spills from ageing, ill-maintained or sabotaged pipelines have increased, and places like Arctic Russia, the Niger Delta, and the northwestern Amazon have become sites of reoccurring oil pollution. As for blowouts, there is no clear trend with regard to the number of incidences or amounts of spilled oil, but deepwater blowouts are much harder to cap and thus tend to go on longer and result in the release of larger quantities of oil. Also, oil exploration and extraction is moving into ever-deeper water and into stormier and icier seas, increasing potential risks. The risk for reoccurring spills like the two huge Mexican Gulf ones is eminent and must be reduced.

Cell separator for use in bipolar-stack energy storage devices

DOEpatents

Mayer, Steven T.; Feikert, John H.; Kachmitter, James L.; Pekala, Richard W.

1995-01-01

An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack.

Short-range wakefields generated in the blowout regime of plasma-wakefield acceleration

NASA Astrophysics Data System (ADS)

Stupakov, G.

2018-04-01

In the past, calculation of wakefields generated by an electron bunch propagating in a plasma has been carried out in linear approximation, where the plasma perturbation can be assumed small and plasma equations of motion linearized. This approximation breaks down in the blowout regime where a high-density electron driver expels plasma electrons from its path and creates a cavity void of electrons in its wake. In this paper, we develop a technique that allows us to calculate short-range longitudinal and transverse wakes generated by a witness bunch being accelerated inside the cavity. Our results can be used for studies of the beam loading and the hosing instability of the witness bunch in plasma-wakefield and laser-wakefield acceleration.

A case of isolated abducens nerve paralysis in maxillofacial trauma

PubMed Central

Keskin, Elif Seda; Keskin, Ekrem; Atik, Bekir; Koçer, Abdülkadir

2015-01-01

Nervus abducens is a pure motor nerve located in the pons. It retracts the eyeball laterally by stimulating rectus lateralis muscle. In case of their paralysis, diplopia and restriction in the eye movements while looking sideways, are seen. Since the same signs are seen due to the muscle entrapment in blowout fractures, its differential diagnosis has importance in terms of the treatment protocol and avoiding unnecessary operations. In this article, we present a 22-year-old male patient who was referred to our department due to the prediagnosis of blowout fracture following maxillofacial trauma. However, he was diagnosed with abducens nerve paralysis after the consultations and analysis and his restriction of movement was resolved via systemic steroid treatment instead of unnecessary operation. PMID:26981484

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

Freifeld, Barry; Oldenburg, Curtis; Jordan, Preston

The 2015-2016 Aliso Canyon/Porter Ranch natural gas well blowout emitted approximately 100,000 tonnes of natural gas (mostly methane, CH 4) over four months. The blowout impacted thousands of nearby residents, who were displaced from their homes. The high visibility of the event has led to increased scrutiny of the safety of natural gas storage at the Aliso Canyon facility, as well as broader concern for natural gas storage integrity throughout the country. This report presents the findings of the DOE National Laboratories Well Integrity Work Group efforts in the four tasks. In addition to documenting the work of the Workmore » Group, this report presents high priority recommendations to improve well integrity and reduce the likelihood and consequences of subsurface natural gas leaks.« less

Investigation of Ruthenium Dissolution in Advanced Membrane Electrode Assemblies for Direct Methanol Based Fuel Cell Stacks

NASA Technical Reports Server (NTRS)

Valdez, Thomas I.; Firdosy, S.; Koel, B. E.; Narayanan, S. R.

2005-01-01

Dissolution of ruthenium was observed in the 80-cell stack. Duration testing was performed in single cell MEAs to determine the pathway of cell degradation. EDAX analysis on each of the single cell MEAs has shown that the Johnson Matthey commercial catalyst is stable in DMFC operation for 250 hours, no ruthenium dissolution was observed. Changes in the hydrophobicity of the cathode backing papers was minimum. Electrode polarization analysis revealed that the MEA performance loss is attributed to changes in the cathode catalyst layer. Ruthenium migration does not seem to occur during cell operation but can occur when methanol is absent from the anode compartment, the cathode compartment has access to air, and the cells in the stack are electrically connected to a load (Shunt Currents). The open-to-air cathode stack design allowed for: a) The MEAs to have continual access to oxygen; and b) The stack to sustain shunt currents. Ruthenium dissolution in a DMFC stack can be prevented by: a) Developing an internally manifolded stacks that seal reactant compartments when not in operation; b) Bringing the cell voltages to zero quickly when not in operation; and c) Limiting the total number of cells to 25 in an effort to limit shunt currents.

Anode protection system for shutdown of solid oxide fuel cell system

DOEpatents

Li, Bob X; Grieves, Malcolm J; Kelly, Sean M

2014-12-30

An Anode Protection Systems for a SOFC system, having a Reductant Supply and safety subsystem, a SOFC anode protection subsystem, and a Post Combustion and slip stream control subsystem. The Reductant Supply and safety subsystem includes means for generating a reducing gas or vapor to prevent re-oxidation of the Ni in the anode layer during the course of shut down of the SOFC stack. The underlying ammonia or hydrogen based material used to generate a reducing gas or vapor to prevent the re-oxidation of the Ni can be in either a solid or liquid stored inside a portable container. The SOFC anode protection subsystem provides an internal pressure of 0.2 to 10 kPa to prevent air from entering into the SOFC system. The Post Combustion and slip stream control subsystem provides a catalyst converter configured to treat any residual reducing gas in the slip stream gas exiting from SOFC stack.

Taming a wild geothermal research well in yellowstone national park

USGS Publications Warehouse

Fournier, Robert O.; Pisto, Larry M.; Howell, Bruce B.; Hutchnson, Roderick A.; ,

1993-01-01

In November 1992 the valve at the top of a U.S. Geological Survey drill hole in Yellowstone National Park parted from the casting as a result of corrosion. This allowed uncontrolled venting of boiling water and steam from the well at an estimated liquid flow rate of about 25-50 gallons per minute. A flow diverter assembly was designed, fabricated and installed on the well within 16 days, which allowed drill rods to be safely stripped into the well through on annular Blow-Out Preventer. Once this was accomplished it was a relatively routine matter to set a packer in the casting and cement the well shut permanently. The drill hole was brought under control and cemented shut within 18 days of the wellhead failure at a total cost of $47,066, which was about $5,000 less than anticipated.

[Endovascular Treatment for Carotid Blowout Syndrome after Radiation for Esophageal Cancer:A Case Report].

PubMed

Takahashi, Shigefumi; Kawaguchi, Tomohiro; Niizuma, Kuniyasu; Nakagawa, Atsuhiro; Fujimura, Miki; Ogawa, Takenori; Katori, Yukio; Tominaga, Teiji

2017-09-01

Here, we discuss a case of carotid blowout syndrome successfully treated with endovascular parent artery occlusion. A 71-year-old woman underwent treatment for esophageal cancer resection, followed by 50-Gy radiotherapy, 19 years prior. Due to local recurrence, she underwent 66- and 72-Gy radiation treatments at 2 and 4 years after the initial treatment, respectively. Afterward, tracheostomy and enterostomy were performed. This time, she was transported to our emergency department because of acute eruptive bleeding from the tracheal tube. As her vitals indicated shock, emergency endovascular treatment was performed. Digital subtraction angiography revealed that the common carotid artery in the left-sided of the neck had a pseudoaneurysm extruding to the pharyngeal cavity, which was considered to be the lesion responsible for the acute rupture. She was diagnosed as having carotid blowout syndrome. Balloon test occlusion showed that the cross flow via the anterior and posterior communicating arteries was sufficient, so parent artery occlusion was chosen for bleeding control. Carotid bifurcation was preserved to keep the collateral circulation via the external carotid artery. The patient was discharged 22 days after treatment, without any neurological deficits. Although injured vessel removal with high-flow bypass was an ideal treatment to achieve bleeding control without ischemic complication, endovascular treatment can be an efficient second-best treatment. To minimize the risk of late ischemic complications, flow preservation via carotid bifurcation might be important.

Deep-Sea Macrobenthos Community Structure Proximal to the 2010 Macondo Well Blowout (2010-2011)

NASA Astrophysics Data System (ADS)

Briggs, K. B.; Brunner, C. A.; Yeager, K. M.

2017-12-01

Macrobenthos, polycyclic aromatic hydrocarbons (PAH) and sedimentary organic carbon (SOC) were sampled by multicorer in the vicinity of the Deepwater Horizon well head in October 2010 and 2011 to assess the effects of the April 2010 spill. Four stations were sampled east of the well head, four stations were sampled west of the well head, and "control" stations were sampled 58 and 65 km to the southwest. The macrobenthos community, as expected for continental slope/bathyal (water depth 1160-1760 m) benthos, was highly diverse. Polychaetes dominated at all stations, with either crustaceans or mollusks comprising the next most abundant taxon. The stations within five km of the well head showed slightly lower diversity than the more distal stations six months after the blowout. Compared to the "control" station, proportions of suspension feeders were generally depressed at stations with high PAH concentrations. Anomalously high values for abundance and diversity (and PAH) were found at one station 20 km west of the well head. The median body size of macrobenthos was negatively correlated with total PAH concentration, with 74% of the variation in median size explained by variation in PAH, when the anomalous station was excluded. Macrobenthos abundance did not appear to be influenced by SOC. Abundance and diversity of the macrobenthos was generally higher 18 months after the blowout, with measured PAH concentrations diminished to below background level.

Method for forming a cell separator for use in bipolar-stack energy storage devices

DOEpatents

Mayer, Steven T.; Feikert, John H.; Kaschmitter, James L.; Pekala, Richard W.

1994-01-01

An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack.

Cell separator for use in bipolar-stack energy storage devices

DOEpatents

Mayer, S.T.; Feikert, J.H.; Kachmitter, J.L.; Pekala, R.W.

1995-02-28

An improved multi-cell electrochemical energy storage device is described, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack. 2 figs.

Method for forming a cell separator for use in bipolar-stack energy storage devices

DOEpatents

Mayer, S.T.; Feikert, J.H.; Kaschmitter, J.L.; Pekala, R.W.

1994-08-09

An improved multi-cell electrochemical energy storage device, such as a battery, fuel cell, or double layer capacitor using a cell separator which allows cells to be stacked and interconnected with low electrical resistance and high reliability while maximizing packaging efficiency. By adding repeating cells, higher voltages can be obtained. The cell separator is formed by applying an organic adhesive on opposing surfaces of adjacent carbon electrodes or surfaces of aerogel electrodes of a pair of adjacent cells prior to or after pyrolysis thereof to form carbon aerogel electrodes. The cell separator is electronically conductive, but ionically isolating, preventing an electrolytic conduction path between adjacent cells in the stack. 2 figs.

Fuel cell stack with internal manifolds for reactant gases

DOEpatents

Schnacke, Arthur W.

1985-01-01

A fuel cell stack includes a plurality of plate-like fuel cells arranged along an axis generally parallel to cell thickness with electrically conductive separator plates between each pair of cells. A plurality of axial manifolds are provided at opposite sides of the stack in outer marginal portions beyond the edges of electrodes and electrolyte tiles. Sealing rings prevent cross-leakage of oxidant fuel gases through use of pairs of outwardly extending lips from opposite tile surfaces bonded to first and second electrode frames respectively. The frames provide transition between electrode edges and manifold perimeters. The pairs of extension lips are sealingly bonded together through an electrically insulative sealing ring with wedge shaped fastening members.

Fuel cell stack with internal manifolds for reactant gases

DOEpatents

Schnacke, A.W.

1983-10-12

A fuel cell stack includes a plurality of plate-like fuel cells arranged along an axis generally parallel to cell thickness with electrically conductive separator plates between each pair of cells. A plurality of axial manifolds are provided at opposite sides of the stack in outer marginal portions beyond the edges of electrodes and electrolyte tiles. Sealing rings prevent cross-leakage of oxidant fuel gases through use of pairs of outwardly extending lips from opposite tile surfaces bonded to first and second electrode frames respectively. The frames provide transition between electrode edges and manifold perimeters. The pairs of extension lips are sealingly bonded together through an electrically insulative sealing ring with wedge shaped fastening members.

Structural and thermodynamic consideration of metal oxide doped GeO{sub 2} for gate stack formation on germanium

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

Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Lee, Choong Hyun; Zhang, Wenfeng

2014-11-07

A systematic investigation was carried out on the material and electrical properties of metal oxide doped germanium dioxide (M-GeO{sub 2}) on Ge. We propose two criteria on the selection of desirable M-GeO{sub 2} for gate stack formation on Ge. First, metal oxides with larger cation radii show stronger ability in modifying GeO{sub 2} network, benefiting the thermal stability and water resistance in M-GeO{sub 2}/Ge stacks. Second, metal oxides with a positive Gibbs free energy for germanidation are required for good interface properties of M-GeO{sub 2}/Ge stacks in terms of preventing the Ge-M metallic bond formation. Aggressive equivalent oxide thickness scalingmore » to 0.5 nm is also demonstrated based on these understandings.« less

Electrically Conductive and Protective Coating for Planar SOFC Stacks

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

Choi, Jung-Pyung; Stevenson, Jeffry W.

Ferritic stainless steels are preferred interconnect materials for intermediate temperature SOFCs because of their resistance to oxidation, high formability and low cost. However, their protective oxide layer produces Cr-containing volatile species at SOFC operating temperatures and conditions, which can cause cathode poisoning. Electrically conducting spinel coatings have been developed to prevent cathode poisoning and to maintain an electrically conductive pathway through SOFC stacks. However, this coating is not compatible with the formation of stable, hermetic seals between the interconnect frame component and the ceramic cell. Thus, a new aluminizing process has been developed by PNNL to enable durable sealing, preventmore » Cr evaporation, and maintain electrical insulation between stack repeat units. Hence, two different types of coating need to have stable operation of SOFC stacks. This paper will focus on the electrically conductive coating process. Moreover, an advanced coating process, compatible with a non-electrically conductive coating will be« less

Ion response to relativistic electron bunches in the blowout regime of laser-plasma accelerators.

PubMed

Popov, K I; Rozmus, W; Bychenkov, V Yu; Naseri, N; Capjack, C E; Brantov, A V

2010-11-05

The ion response to relativistic electron bunches in the so called bubble or blowout regime of a laser-plasma accelerator is discussed. In response to the strong fields of the accelerated electrons the ions form a central filament along the laser axis that can be compressed to densities 2 orders of magnitude higher than the initial particle density. A theory of the filament formation and a model of ion self-compression are proposed. It is also shown that in the case of a sharp rear plasma-vacuum interface the ions can be accelerated by a combination of three basic mechanisms. The long time ion evolution that results from the strong electrostatic fields of an electron bunch provides a unique diagnostic of laser-plasma accelerators.

Short-range wakefields generated in the blowout regime of plasma-wakefield acceleration

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

Stupakov, G.

In the past, calculation of wakefields generated by an electron bunch propagating in a plasma has been carried out in linear approximation, where the plasma perturbation can be assumed small and plasma equations of motion linearized. This approximation breaks down in the blowout regime where a high-density electron driver expels plasma electrons from its path and creates a cavity void of electrons in its wake. Here in this paper, we develop a technique that allows us to calculate short-range longitudinal and transverse wakes generated by a witness bunch being accelerated inside the cavity. Our results can be used for studiesmore » of the beam loading and the hosing instability of the witness bunch in plasma-wakefield and laser-wakefield acceleration.« less

Flow-diverter in radiation-induced skull base carotid blowout syndrome: do not write it off!

PubMed

Anil, Gopinathan; Zhang, Junwei; Ong, Yew Kwang; Hui, Francis

2017-10-01

Post-radiotherapy carotid blowout syndrome (CBS) of the skull base is a rare but often catastrophic complication of head and neck malignancies. The existing literature on the treatment of this condition with flow-diverting devices (FDD) is extremely limited and disappointing. We present a case of impending CBS in a patient previously irradiated for nasopharyngeal cancer that was successfully treated with use of multiple FDDs, adjunctive endonasal packing and delayed reinforcement with pedicled naso-septal flap, yielding an excellent outcome at 14-months follow-up. Notwithstanding the discouraging results in literature, our anecdotal experience suggests that endovascular reconstruction using FDD could be an option with long-term viability in post-radiotherapy CBS involving the skull base when reinforced with a vascularised naso-septal flap.

Short-range wakefields generated in the blowout regime of plasma-wakefield acceleration

DOE PAGES

Stupakov, G.

2018-04-02

In the past, calculation of wakefields generated by an electron bunch propagating in a plasma has been carried out in linear approximation, where the plasma perturbation can be assumed small and plasma equations of motion linearized. This approximation breaks down in the blowout regime where a high-density electron driver expels plasma electrons from its path and creates a cavity void of electrons in its wake. Here in this paper, we develop a technique that allows us to calculate short-range longitudinal and transverse wakes generated by a witness bunch being accelerated inside the cavity. Our results can be used for studiesmore » of the beam loading and the hosing instability of the witness bunch in plasma-wakefield and laser-wakefield acceleration.« less

Real-Time Control of Lean Blowout in a Turbine Engine for Minimizing No(x) Emissions

NASA Technical Reports Server (NTRS)

Zinn, Ben

2004-01-01

This report describes research on the development and demonstration of a controlled combustor operates with minimal NO, emissions, thus meeting one of NASA s UEET program goals. NO(x) emissions have been successfully minimized by operating a premixed, lean burning combustor (modeling a lean prevaporized, premixed LPP combustor) safely near its lean blowout (LBO) limit over a range of operating conditions. This was accomplished by integrating the combustor with an LBO precursor sensor and closed-loop, rule-based control system that allowed the combustor to operate far closer to the point of LBO than an uncontrolled combustor would be allowed to in a current engine. Since leaner operation generally leads to lower NO, emissions, engine NO, was reduced without loss of safety.

Wind Texture

NASA Image and Video Library

2011-03-23

On Earth, these wind-derived features are called blowouts, where the force of the wind has carved out a crescent-shaped depression in soft, uncemented material like glacial loess. This image is from NASA Mars Odyssey.

A discrete three-layer stack aggregate of a linear porphyrin tetramer: solution-phase structure elucidation by NMR and X-ray scattering.

PubMed

Hutin, Marie; Sprafke, Johannes K; Odell, Barbara; Anderson, Harry L; Claridge, Tim D W

2013-08-28

Formation of stacked aggregates can dramatically alter the properties of aromatic π-systems, yet the solution-phase structure elucidation of these aggregates is often impossible because broad distributions of species are formed, giving uninformative spectroscopic data. Here, we show that a butadiyne-linked zinc porphyrin tetramer forms a remarkably well-defined aggregate, consisting of exactly three molecules, in a parallel stacked arrangement (in chloroform at room temperature; concentration 1 mM-0.1 μM). The aggregate has a mass of 14.7 kDa. Unlike most previously reported aggregates, it gives sharp NMR resonances and aggregation is in slow exchange on the NMR time scale. The structure was elucidated using a range of NMR techniques, including diffusion-editing, (1)H-(29)Si HMBC, (1)H-(1)H COSY, TOCSY and NOESY, and (1)H-(13)C edited HSQC spectroscopy. Surprisingly, the (1)H-(1)H COSY spectrum revealed many long-range residual dipolar couplings (RDCs), and detailed analysis of magnetic field-induced (1)H-(13)C RDCs provided further evidence for the structural model. The size and shape of the aggregate is supported by small-angle X-ray scattering (SAXS) data. It adopts a geometry that maximizes van der Waals contact between the porphyrins, while avoiding clashes between side chains. The need for interdigitation of the side chains prevents formation of stacks consisting of more than three layers. Although a detailed analysis has only been carried out for one compound (the tetramer), comparison with the NMR spectra of other oligomers indicates that they form similar three-layer stacks. In all cases, aggregation can be prevented by addition of pyridine, although at low pyridine concentrations, disaggregation takes many hours to reach equilibrium.

Electrical power from sea and river water by reverse electrodialysis: a first step from the laboratory to a real power plant.

PubMed

Veerman, Joost; Saakes, Michel; Metz, Sybrand J; Harmsen, G Jan

2010-12-01

Electricity can be produced directly with reverse electrodialysis (RED) from the reversible mixing of two solutions of different salinity, for example, sea and river water. The literature published so far on RED was based on experiments with relatively small stacks with cell dimensions less than 10 × 10 cm(2). For the implementation of the RED technique, it is necessary to know the challenges associated with a larger system. In the present study we show the performance of a scaled-up RED stack, equipped with 50 cells, each measuring 25 × 75 cm(2). A single cell consists of an AEM (anion exchange membrane) and a CEM (cation exchange membrane) and therefore, the total active membrane area in the stack is 18.75 m(2). This is the largest dimension of a reverse electrodialysis stack published so far. By comparing the performance of this stack with a small stack (10 × 10 cm(2), 50 cells) it was found that the key performance parameter to maximal power density is the hydrodynamic design of the stack. The power densities of the different stacks depend on the residence time of the fluids in the stack. For the large stack this was negatively affected by the increased hydrodynamic losses due to the longer flow path. It was also found that the large stack generated more power when the sea and river water were flowing in co-current operation. Co-current flow has other advantages, the local pressure differences between sea and river water compartments are low, hence preventing leakage around the internal manifolds and through pinholes in the membranes. Low pressure differences also enable the use of very thin membranes (with low electrical resistance) as well as very open spacers (with low hydrodynamic losses) in the future. Moreover, we showed that the use of segmented electrodes increase the power output by 11%.

Research and application of borehole structure optimization based on pre-drill risk assessment

NASA Astrophysics Data System (ADS)

Zhang, Guohui; Liu, Xinyun; Chenrong; Hugui; Yu, Wenhua; Sheng, Yanan; Guan, Zhichuan

2017-11-01

Borehole structure design based on pre-drill risk assessment and considering risks related to drilling operation is the pre-condition for safe and smooth drilling operation. Major risks of drilling operation include lost circulation, blowout, sidewall collapsing, sticking and failure of drilling tools etc. In the study, studying data from neighboring wells was used to calculate the profile of formation pressure with credibility in the target well, then the borehole structure design for the target well assessment by using the drilling risk assessment to predict engineering risks before drilling. Finally, the prediction results were used to optimize borehole structure design to prevent such drilling risks. The newly-developed technique provides a scientific basis for lowering probability and frequency of drilling engineering risks, and shortening time required to drill a well, which is of great significance for safe and high-efficient drilling.

30 CFR 250.130 - Why does MMS conduct inspections?

Code of Federal Regulations, 2011 CFR

2011-07-01

... approved Exploration Plan or Development and Production Plans; or right-of-use and easement, and other... blowouts, fires, spillages, or other major accidents has been installed and is operating properly according...

The COSIMA experiments and their verification, a data base for the validation of two phase flow computer codes

NASA Astrophysics Data System (ADS)

Class, G.; Meyder, R.; Stratmanns, E.

1985-12-01

The large data base for validation and development of computer codes for two-phase flow, generated at the COSIMA facility, is reviewed. The aim of COSIMA is to simulate the hydraulic, thermal, and mechanical conditions in the subchannel and the cladding of fuel rods in pressurized water reactors during the blowout phase of a loss of coolant accident. In terms of fuel rod behavior, it is found that during blowout under realistic conditions only small strains are reached. For cladding rupture extremely high rod internal pressures are necessary. The behavior of fuel rod simulators and the effect of thermocouples attached to the cladding outer surface are clarified. Calculations performed with the codes RELAP and DRUFAN show satisfactory agreement with experiments. This can be improved by updating the phase separation models in the codes.

Premixing quality and flame stability: A theoretical and experimental study

NASA Technical Reports Server (NTRS)

Radhakrishnan, K.; Heywood, J. B.; Tabaczynski, R. J.

1979-01-01

Models for predicting flame ignition and blowout in a combustor primary zone are presented. A correlation for the blowoff velocity of premixed turbulent flames is developed using the basic quantities of turbulent flow, and the laminar flame speed. A statistical model employing a Monte Carlo calculation procedure is developed to account for nonuniformities in a combustor primary zone. An overall kinetic rate equation is used to describe the fuel oxidation process. The model is used to predict the lean ignition and blow out limits of premixed turbulent flames; the effects of mixture nonuniformity on the lean ignition limit are explored using an assumed distribution of fuel-air ratios. Data on the effects of variations in inlet temperature, reference velocity and mixture uniformity on the lean ignition and blowout limits of gaseous propane-air flames are presented.

RECURRENT SOLAR JETS INDUCED BY A SATELLITE SPOT AND MOVING MAGNETIC FEATURES

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

Chen, Jie; Su, Jiangtao; Yin, Zhiqiang

2015-12-10

Recurrent and homologous jets were observed to the west edge of active region NOAA 11513 at the boundary of a coronal hole. We find two kinds of cancellations between opposite polarity magnetic fluxes, inducing the generation of recurrent jets. First, a satellite spot continuously collides with a pre-existing opposite polarity magnetic field and causes recurrent solar jets. Second, moving magnetic features, which emerge near the sunspot penumbra, pass through the ambient plasma and eventually collide with the opposite polarity magnetic field. Among these recurrent jets, a blowout jet that occurred around 21:10 UT is investigated. The rotation of the pre-existingmore » magnetic field and the shear motion of the satellite spot accumulate magnetic energy, which creates the possibility for the jet to experience blowout right from the standard.« less

Developments in new aircraft tire tread materials. [fatigue life of elastomeric materials

NASA Technical Reports Server (NTRS)

Yager, T. J.; Mccarty, J. L.; Riccitiello, S. R.; Golub, M. A.

1976-01-01

Comparative laboratory and field tests were conducted on experimental and state-of-the-art aircraft tire tread materials in a program aimed at seeking new elastomeric materials which would provide improved aircraft tire tread wear, traction, and blowout resistance in the interests of operational safety and economy. The experimental stock was formulated of natural rubber and amorphous vinyl polybutadiene to provide high thermal-oxidative resistance, a characteristic pursued on the premise that thermal oxidation is involved both in the normal abrasion or wear of tire treads and probably in the chain of events leading to blowout failures. Results from the tests demonstrate that the experimental stock provided better heat buildup (hysteresis) and fatigue properties, at least equal wet and dry traction, and greater wear resistance than the state-of-the-art stock.

Simulation and assessment of SO2 toxic environment after ignition of uncontrolled sour gas flow of well blowout in hills.

PubMed

Zhu, Yuan; Chen, Guo-ming

2010-06-15

To study the sulfur dioxide (SO(2)) toxic environment after the ignition of uncontrolled sour gas flow of well blowout, we propose an integrated model to simulate the accident scenario and assess the consequences of SO(2) poisoning. The accident simulation is carried out based on computational fluid dynamics (CFD), which is composed of well blowout dynamics, combustion of sour gas, and products dispersion. Furthermore, detailed complex terrains are built and boundary layer flows are simulated according to Pasquill stability classes. Then based on the estimated exposure dose derived from the toxic dose-response relationship, quantitative assessment is carried out by using equivalent emergency response planning guideline (ERPG) concentration. In this case study, the contaminated areas are graded into three levels, and the areas, maximal influence distances, and main trajectories are predicted. We show that wind drives the contamination and its distribution to spread downwind, and terrains change the distribution shape through spatial aggregation and obstacles. As a result, the most dangerous regions are the downwind areas, the foot of the slopes, and depression areas such as valleys. These cause unfavorable influences on emergency response for accident control and public evacuation. In addition, the effectiveness of controlling the number of deaths by employing ignition is verified in theory. Based on the assessment results, we propose some suggestions for risk assessment, emergency response and accident decision making. Copyright 2010 Elsevier B.V. All rights reserved.

Development and testing of a contamination potential mapping system for a portion of the General Separations Area, Savannah River Site, South Carolina

USGS Publications Warehouse

Rine, J.M.; Berg, R.C.; Shafer, J.M.; Covington, E.R.; Reed, J.K.; Bennett, C.B.; Trudnak, J.E.

1998-01-01

A methodology was developed to evaluate and map the contamination potential or aquifer sensitivity of the upper groundwater flow system of a portion of the General Separations Area (GSA) at the Department of Energy's Savannah River Site (SRS) in South Carolina. A Geographic Information System (GIS) was used to integrate diverse subsurface geologic data, soils data, and hydrology utilizing a stack-unit mapping approach to construct mapping layers. This is the first time that such an approach has been used to delineate the hydrogeology of a coastal plain environment. Unit surface elevation maps were constructed for the tops of six Tertiary units derived from over 200 boring logs. Thickness or isopach maps were created for five hydrogeologic units by differencing top and basal surface elevations. The geologic stack-unit map was created by stacking the five isopach maps and adding codes for each stack-unit polygon. Stacked-units were rated according to their hydrogeologic properties and ranked using a logarithmic approach (utility theory) to establish a contamination potential index. Colors were assigned to help display relative importance of stacked-units in preventing or promoting transport of contaminants. The sensitivity assessment included the effects of surface soils on contaminants which are particularly important for evaluating potential effects from surface spills. Hydrogeologic/hydrologic factors did not exhibit sufficient spatial variation to warrant incorporation into contamination potential assessment. Development of this contamination potential mapping system provides a useful tool for site planners, environmental scientists, and regulatory agencies.A methodology was developed to evaluate and map the contamination potential or aquifer sensitivity of the upper groundwater flow system of a portion of the General Separations Area (GSA) at the Department of Energy's Savannah River Site (SRS) in South Carolina. A Geographic Information System (GIS) was used to integrate diverse subsurface geologic data, soils data, and hydrology utilizing a stack-unit mapping approach to construct mapping layers. This is the first time that such an approach has been used to delineate the hydrogeology of a coastal plain environment. Unit surface elevation maps were constructed for the tops of six Tertiary units derived from over 200 boring logs. Thickness or isopach maps were created for five hydrogeologic units by differencing top and basal surface elevations. The geologic stack-unit map was created by stacking the five isopach maps and adding codes for each stack-unit polygon. Stacked-units were rated according to their hydrogeologic properties and ranked using a logarithmic approach (utility theory) to establish a contamination potential index. Colors were assigned to help display relative importance of stacked-units in preventing or promoting transport of contaminants. The sensitivity assessment included the effects of surface soils on contaminants which are particularly important for evaluating potential effects from surface spills. Hydrogeologic/hydrologic factors did not exhibit sufficient spatial variation to warrant incorporation into contamination potential assessment. Development of this contamination potential mapping system provides a useful tool for site planners, environmental scientists, and regulatory agencies.

Lamination cooling system

DOEpatents

Rippel, Wally E.; Kobayashi, Daryl M.

2005-10-11

An electric motor, transformer or inductor having a lamination cooling system including a stack of laminations, each defining a plurality of apertures at least partially coincident with apertures of adjacent laminations. The apertures define a plurality of cooling-fluid passageways through the lamination stack, and gaps between the adjacent laminations are sealed to prevent a liquid cooling fluid in the passageways from escaping between the laminations. The gaps are sealed by injecting a heat-cured sealant into the passageways, expelling excess sealant, and heat-curing the lamination stack. The apertures of each lamination can be coincident with the same-sized apertures of adjacent laminations to form straight passageways, or they can vary in size, shape and/or position to form non-axial passageways, angled passageways, bidirectional passageways, and manifold sections of passageways that connect a plurality of different passageway sections. Manifold members adjoin opposite ends of the lamination stack, and each is configured with one or more cavities to act as a manifold to adjacent passageway ends. Complex manifold arrangements can create bidirectional flow in a variety of patterns.

Underinflated tires in the United States

DOT National Transportation Integrated Search

2007-02-09

Underinflated tires impact a drivers ability to control a vehicle against skidding, blowouts, and other tire failures. While not a leading cause of highway accidents and fatalities, a NHTSA study shows that, in 1999, underinflated tires contribute...

Polycyclic aromatic hydrocarbon (PAH)-containing soils from coal gangue stacking areas contribute to epithelial to mesenchymal transition (EMT) modulation on cancer cell metastasis.

PubMed

Yun, Yang; Gao, Rui; Yue, Huifeng; Liu, Xiaofang; Li, Guangke; Sang, Nan

2017-02-15

The total accumulative stockpiles of gangue in China comprise 4.5billion metric tons, and approximately 659million tons of additional gangue are generated per year. Considering the stacking characteristics are highly heterogeneous, the potential cancer risks from the presence of polycyclic aromatic hydrocarbons (PAHs) remain elusive. This study aimed to determine whether PAH-containing soil around coal gangue stacking areas poses a potential cancer risk and contributes to cancer cell metastasis. The results indicate that eighteen PAHs, primarily originated from coal gangue, exhibited distance variations from the coal gangues to the downstream villages, and the abandoned colliery posed increased potential carcinogenic risks for humans as a result of long-term stacking of coal gangue. Furthermore, soil samples stimulated HepG2 cell migration and invasion in a PAH-dependent manner, and the action was involved in PPARγ-mediated epithelial to mesenchymal transition (EMT) modulation. These findings highlight the potential cancer risk of PAH-containing soil samples around coal gangue stacking areas, and identify important biomarkers underlying the risk and targets preventing the outcomes in polluted areas. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular mechanism of direct proflavine-DNA intercalation: evidence for drug-induced minimum base-stacking penalty pathway.

PubMed

Sasikala, Wilbee D; Mukherjee, Arnab

2012-10-11

DNA intercalation, a biophysical process of enormous clinical significance, has surprisingly eluded molecular understanding for several decades. With appropriate configurational restraint (to prevent dissociation) in all-atom metadynamics simulations, we capture the free energy surface of direct intercalation from minor groove-bound state for the first time using an anticancer agent proflavine. Mechanism along the minimum free energy path reveals that intercalation happens through a minimum base stacking penalty pathway where nonstacking parameters (Twist→Slide/Shift) change first, followed by base stacking parameters (Buckle/Roll→Rise). This mechanism defies the natural fluctuation hypothesis and provides molecular evidence for the drug-induced cavity formation hypothesis. The thermodynamic origin of the barrier is found to be a combination of entropy and desolvation energy.

Implementation of Stack Height Regulations - Exceptions from Restrictions on Credit for Merged Stacks

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Retrospective Case Study in Killdeer, North Dakota

EPA Pesticide Factsheets

This study site was chosen at the request of the state to specifically examine any water resource impacts from a well blowout in September 2010 that resulted in an uncontrolled release of hydraulic fracturing fluids and formation fluids.

[Medpor plus titanic mesh implant in the repair of orbital blowout fractures].

PubMed

Han, Xiao-hui; Zhang, Jia-yu; Cai, Jian-qiu; Shi, Ming-guang

2011-05-10

To study the efficacy of porous polyethylene (Medpor) plus titanic mesh sheets in the repair of orbital blowout fractures. A total of 20 patients underwent open surgical reduction with the combined usage of Medpor and titanic mesh. And they were followed up for average period of 14.5 months (range: 9 - 18). There is no infection or extrusion of medpor and titanic mesh in follow-up periods. There was no instance of decreased visual acuity at post-operation. And all cases of enophthalmos were corrected. The post-operative protrusion degree of both eyes was almost identical at less than 2 mm. The movement of eye balls was satisfactory in all directions. Diplopia disappeared in 18 cases with a cure rate of 90%, 1 case improved and 1 case persisted. Medpor plus titanic mesh implant is a safe and effective treatment in the repair of orbital blow out fractures.

Afterburner performance of film-vaporizing V-gutters for inlet temperatures up to 1255 K

NASA Technical Reports Server (NTRS)

Branstetter, J. R.; Reck, G. M.

1973-01-01

Combustion tests of five variations of an integral, spray-bar - flameholder combination were conducted in a 0.49-m-diameter duct. Emphasis was on low levels of augmentation. Fuel impinged on guide plates, mixed with a controlled amount of inlet air, vaporized, and was guided into the V-gutter wake. Combustor length was 0.92 m. Good performance was demonstrated at fuel-air ratios less than 0.025 for inlet temperatures of 920 to 1255 K. Maximum combustion efficiency occured in the vicinity of fuel-air ratios of 0.02 and was 92 to 100 percent, depending on the inlet temperature. Lean blowout fuel-air ratios were in the vicinity of 0.005. Improvements in rich-limit blowout resulted from enlarging the guide-flow passageway areas. Other means of extending the operating range are suggested. A simplified afterburner concept for application to advanced engines is described.

Beam-driven acceleration in ultra-dense plasma media

DOE PAGES

Shin, Young-Min

2014-09-15

Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 10 25 m -3 and 1.6 x 10 28 m -3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlargingmore » the channel radius (r) from 0.2 Ap to 0.6 .Ap in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.« less

Aviation fuel property effects on altitude relight

NASA Technical Reports Server (NTRS)

Venkataramani, K.

1987-01-01

The major objective of this experimental program was to investigate the effects of fuel property variation on altitude relight characteristics. Four fuels with widely varying volatility properties (JP-4, Jet A, a blend of Jet A and 2040 Solvent, and Diesel 2) were tested in a five-swirl-cup-sector combustor at inlet temperatures and flows representative of windmilling conditions of turbofan engines. The effects of fuel physical properties on atomization were eliminated by using four sets of pressure-atomizing nozzles designed to give the same spray Sauter mean diameter (50 + or - 10 micron) for each fuel at the same design fuel flow. A second series of tests was run with a set of air-blast nozzles. With comparable atomization levels, fuel volatility assumes only a secondary role for first-swirl-cup lightoff and complete blowout. Full propagation first-cup blowout were independent of fuel volatility and depended only on the combustor operating conditions.

Transarterial endovascular treatment in the management of life-threatening carotid blowout syndrome in head and neck cancer patients: review of the literature.

PubMed

Dequanter, D; Shahla, M; Paulus, P; Aubert, C; Lothaire, P

2013-12-01

Carotid blowout syndrome is a rare but devastating complication in patients with head and neck malignancy, and is associated with high morbidity and mortality. Bleeding from the carotid artery or its branches is a well-recognized complication following treatment or recurrence of head and neck cancer. It is an emergency situation, and the classical approach to save the patient's life is to ligate the carotid artery. But the surgical treatment is often technically difficult. Endovascular therapies were recently reported as good alternatives to surgical ligation. Retrospective review of three cases of acute or threatened carotid hemorrhage managed by endovascular therapies. Two patients presented with acute carotid blowout, and one patient with a sentinel bleed. Two patients had previously been treated with surgery and chemo radiation. One patient was treated by chemo radiation. Two had developed pharyngocutaneous fistulas, and one had an open necrosis filled wound that surrounded the carotid artery. In two patients, stent placement resolved the acute hemorrhage. In one patient, superselective embolization was done. Mean duration follow-up was 10.2 months. No patient had residual sequelae of stenting or embolization. Management of carotid blow syndrome is very critical and difficult. A multidisciplinary approach is very important in the management of carotid blow syndrome. Correct and suitable management can be life saving. An endovascular technique is a good and effective alternative with much lower morbidity rates than surgical repair or ligation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Adhesion promoters for large scale fabrication of dielectric elastomer stack transducers (DESTs) made of pre-fabricated dielectric films

NASA Astrophysics Data System (ADS)

Grotepaß, T.; Förster-Zügel, F.; Mößinger, H.; Schlaak, H. F.

2015-04-01

Multilayer dielectric elastomer stack transducers (DESTs) are a promising new transducer technology with many applications in different industry sectors, like medical devices, human-machine-interaction, etc. Stacked dielectric elastomer transducers show larger thickness contraction driven by lower voltages than transducers made from a single dielectric layer. Traditionally multilayered DESTs are produced by repeatedly cross-linking a liquid elastomeric pre-polymer into the required shape. Our recent research focusses on a novel fabrication method for large scale stack transducers with a surface area over 200 x 300 mm by processing pre-fabricated elastomeric thin films of less than 50 μm thicknesses. The thin films are provided as two- or three-layer composites, where the elastomer is sandwiched between one or two sacrificial liners. Separating the elastomeric film from the residual layers and assembling them into dielectric elastomer stack transducers poses many challenges concerning adhesion, since the dielectric film merely separates from the liner if the adhesive forces between them are overcome. Conversely, during the assembly of a dielectric elastomer stack transducer, adhesive forces have to be established between two elastomeric layers or between the dielectric and the electrode layer. The very low Young's modulus of at least one adhesion partner requires suitable means of increasing the adhesive forces between the different adhesive layers of a dielectric elastomer stack transducer to prevent a delamination of the transducer during its lifetime. This work evaluates different surface activation treatments - corona, low-pressure plasma and UV-light - and their applicability in the production of large scale DESTs made from pre-fabricated elastomeric films.

Dual-Mode Scramjet Flameholding Operability Measurements

NASA Technical Reports Server (NTRS)

Donohue, James M.

2012-01-01

Flameholding measurements were made in two different direct connect combustor facilities that were designed to simulate a cavity flameholder in the flowfield of a hydrocarbon fueled dual-mode scramjet combustor. The presence of a shocktrain upstream of the flameholder has a significant impact on the inlet flow to the combustor and on the flameholding limits. A throttle was installed in the downstream end of the test rigs to provide the needed back-pressurization and decouple the operation of the flameholder from the backpressure formed by heat release and thermal choking, as in a flight engine. Measurements were made primarily with ethylene fuel but a limited number of tests were also performed with heated gaseous JP-7 fuel injection. The flameholding limits were measured by ramping inlet air temperature down until blowout was observed. The tests performed in the United Technologies Research Center (UTRC) facility used a hydrogen fueled vitiated air heater, Mach 2.2 and 3.3 inlet nozzles, a scramjet combustor rig with a 1.666 by 6 inch inlet and a 0.65 inch deep cavity. Mean blowout temperature measured at the baseline condition with ethylene fuel, the Mach 2.2 inlet and a cavity pressure of 21 psia was 1502 oR. Flameholding sensitivity to a variety of parameters was assessed. Blowout temperature was found to be most sensitive to fuel injection location and fuel flowrates and surprisingly insensitive to operating pressure (by varying both back-pressurization and inlet flowrate) and inlet Mach number. Video imaging through both the bottom and side wall windows was collected simultaneously and showed that the flame structure was quite unsteady with significant lateral movements as well as movement upstream of the flameholder. Experiments in the University of Virginia (UVa) test facility used a Mach 2 inlet nozzle with a 1 inch by 1.5 inch exit cross section, an aspect ratio of 1.5 versus 3.6 in the UTRC facility. The UVa facility tests were designed to measure the sensitivity of flameholding limits to inlet air vitiation by using electrically heated air and adding steam at levels to simulate vitiated air heaters. The measurements showed no significant difference in blowout temperature with inlet air mole fractions of steam from 0 to 6.7%.

Performance Testing of Tracer Gas and Tracer Aerosol Detectors for use in Radionuclide NESHAP Compliance Testing

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

Fuehne, David Patrick; Lattin, Rebecca Renee

The Rad-NESHAP program, part of the Air Quality Compliance team of LANL’s Compliance Programs group (EPC-CP), and the Radiation Instrumentation & Calibration team, part of the Radiation Protection Services group (RP-SVS), frequently partner on issues relating to characterizing air flow streams. This memo documents the most recent example of this partnership, involving performance testing of sulfur hexafluoride detectors for use in stack gas mixing tests. Additionally, members of the Rad-NESHAP program performed a functional trending test on a pair of optical particle counters, comparing results from a non-calibrated instrument to a calibrated instrument. Prior to commissioning a new stack samplingmore » system, the ANSI Standard for stack sampling requires that the stack sample location must meet several criteria, including uniformity of tracer gas and aerosol mixing in the air stream. For these mix tests, tracer media (sulfur hexafluoride gas or liquid oil aerosol particles) are injected into the stack air stream and the resulting air concentrations are measured across the plane of the stack at the proposed sampling location. The coefficient of variation of these media concentrations must be under 20% when evaluated over the central 2/3 area of the stack or duct. The instruments which measure these air concentrations must be tested prior to the stack tests in order to ensure their linear response to varying air concentrations of either tracer gas or tracer aerosol. The instruments used in tracer gas and aerosol mix testing cannot be calibrated by the LANL Standards and Calibration Laboratory, so they would normally be sent off-site for factory calibration by the vendor. Operational requirements can prevent formal factory calibration of some instruments after they have been used in hazardous settings, e.g., within a radiological facility with potential airborne contamination. The performance tests described in this document are intended to demonstrate the reliable performance of the test instruments for the specific tests used in stack flow characterization.« less

Effect of Na presence during CuInSe{sub 2} growth on stacking fault annihilation and electronic properties

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

Stange, H., E-mail: helena.stange@helmholtz-berlin.de; Brunken, S.; Hempel, H.

While presence of Na is essential for the performance of high-efficiency Cu(In,Ga)Se{sub 2} thin film solar cells, the reasons why addition of Na by post-deposition treatment is superior to pre-deposition Na supply—particularly at low growth temperatures—are not yet fully understood. Here, we show by X-ray diffraction and electron microscopy that Na impedes annihilation of stacking faults during the Cu-poor/Cu-rich transition of low temperature 3-stage co-evaporation and prevents Cu homogeneity on a microscopic level. Lower charge carrier mobilities are found by optical pump terahertz probe spectroscopy for samples with remaining high stacking fault density, indicating a detrimental effect on electronic propertiesmore » if Na is present during growth.« less

Fun in the Sun for School-Agers.

ERIC Educational Resources Information Center

Hanus, Maggie

1996-01-01

Tells how caregivers planning summertime theme-oriented special events for children can build enthusiasm, encourage cooperation, and provide fun activities. Presents four themes: (1) "Beach Blast"; (2) "Splash Day"; (3) "Crazy Carnival"; and (4) "Balloon Blowout." Describes several activities in each…

Chemical Safety Alert: Shaft Blow-Out Hazard of Check and Butterfly Valves

EPA Pesticide Factsheets

Certain types of check and butterfly valves can undergo shaft-disk separation and fail catastrophically, even when operated within their design limits of pressure and temperature, causing toxic/flammable gas releases, fires, and vapor cloud explosions.

Analysis of Flow Migration in an Ultra-Compact Combustor

DTIC Science & Technology

2011-03-01

Computational Fluid Dynamics . . . . . . . . . . . . . . . 6 UNICORN Unsteady Ignition and Combustion with Reactions . . . . 8 LBO Lean Blowout...the magnitude of enhanced flame speeds due to g- loading using the UNICORN CFD code. The study examined flame propagation for a hydrogen-air mixture in

77 FR 26562 - Mobile Offshore Drilling Unit Dynamic Positioning Guidance

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-04

... regarding a draft policy letter on Dynamic Positioning (DP) Systems, Emergency Disconnect Systems, Blowout... Coast Guard, NOSAC issued the report ``Recommendations for Dynamic Positioning System Design and... DEPARTMENT OF HOMELAND SECURITY Coast Guard [USCG-2011-1106] Mobile Offshore Drilling Unit Dynamic...

Fibrillar Chromospheric Spicule-Like Counterparts to an EUV and Soft X-Ray Blowout Coronal Jet

NASA Technical Reports Server (NTRS)

Sterling, Alphonse C.; Harra, Louise K.; Moore, Ronald L.

2010-01-01

We observe an erupting jet feature in a solar polar coronal hole, using data from Hinode/SOT, EIS, and XRT, with supplemental data from STEREO/EUVI. From EUV and soft X-ray (SXR) images we identify the erupting feature as a blowout coronal jet: in SXRs it is a jet with bright base, and in EUV it appears as an eruption of relatively cool (approximately 50,000 K) material of horizontal size scale approximately 30" originating from the base of the SXR jet. In SOT Ca II H images the most pronounced analog is a pair of thin (approximately 1") ejections, at the locations of either of the two legs of the erupting EUV jet. These Ca II features eventually rise beyond 45", leaving the SOT field of view, and have an appearance similar to standard spicules except that they are much taller. They have velocities similar to that of "type II" spicules, approximately 100 kilometers per second, and they appear to have spicule-like substructures splitting off from them with horizontal velocity approximately 50 kilometers per second, similar to the velocities of splitting spicules measured by Sterling et al. (2010). Motions of splitting features and of other substructures suggest that the macroscopic EUV jet is spinning or unwinding as it is ejected. This and earlier work suggests that a sub-population of Ca II type II spicules are the Ca II manifestation of portions of larger-scale erupting magnetic jets. A different sub-population of type II spicules could be blowout jets occurring on a much smaller horizontal size scale than the event we observe here.

Emissions due to the natural gas storage well-casing blowout at Aliso Canyon/SS-25

NASA Astrophysics Data System (ADS)

Herndon, Scott; Daube, Conner; Jervis, Dylan; Yacovitch, Tara; Roscioli, Joseph; Curry, Jason; Nelson, David; Knighton, Berk

2017-04-01

The pronounced increase in unconventional gas production in North America over the last fifteen years has intensified interest in understanding emissions and leaks in the supply chain from well pad to end use. Los Angeles, California is home 19 million consumers of natural gas in both industry and domestic end use. The well blowout at Aliso Canyon Natural Gas Storage Facility in the greater Los Angeles area was quantified using the tracer flux ratio method (TFR). Over 400 tracer plume transects were collected, each lasting 15-300 seconds, using instrumentation aboard a mobile platform on 25 days between December 21, 2015 and March 9, 2016. The leak rate from October 23rd to February 11th has been estimated here using a combination of this work (TFR) and the flight mass balance (FMB) data [Conley et al., 2016]. This estimate relies on the TFR data as the most specific SS-25 emission dataset. Scaling the FMB dataset, the leak rate is projected from Oct 23rd to December 21th. Adding up the emissions inferred and measured suggests a total leak burden of 86,022 ± 8,393 metric tons of methane. This work quantified the emissions during the "bottom kill" procedure which halted the primary emission leak. The ethane to methane enhancement ratio observed downwind of the leak site is consistent with the content of ethane in the natural gas at this site and provides definitive evidence that the methane emission rate quantified via tracer flux ratio is not due to a nearby landfill or other potential biogenic sources. Additionally, the TFR approach employed here is assessing only the leaks due to the SS-25 well blowout and excludes other possible emissions at the facility.

LINE-OF-SIGHT SHELL STRUCTURE OF THE CYGNUS LOOP

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

Uchida, Hiroyuki; Tsunemi, Hiroshi; Katsuda, Satoru

We conducted a comprehensive study on the shell structure of the Cygnus Loop using 41 observation data obtained by the Suzaku and the XMM-Newton satellites. To investigate the detailed plasma structure of the Cygnus Loop, we divided our fields of view into 1042 box regions. From the spectral analysis, the spectra obtained from the limb of the Loop are well fitted by the single-component non-equilibrium ionization plasma model. On the other hand, the spectra obtained from the inner regions are well fitted by the two-component model. As a result, we confirmed that the low-temperature and high-temperature components originated from themore » surrounding interstellar matter (ISM) and the ejecta of the Loop, respectively. From the best-fit results, we showed a flux distribution of the ISM component. The distribution clearly shows the limb-brightening structure, and we found out some low-flux regions. Among them, the south blowout region has the lowest flux. We also found other large low-flux regions at slightly west and northeast from the center. We estimated the former thin shell region to be approx1.{sup 0}3 in diameter and concluded that there exists a blowout along the line of sight in addition to the south blowout. We also calculated the emission measure distribution of the ISM component and showed that the Cygnus Loop is far from the result obtained by a simple Sedov evolution model. From the results, we support that the Cygnus Loop originated from a cavity explosion. The emission measure distribution also suggests that the cavity-wall density is higher in the northeast than that in the southwest. These results suggest that the thickness of the cavity wall surrounding the Cygnus Loop is not uniform.« less

METHODOLOGY TO EVALUATE THE POTENTIAL FOR GROUND WATER CONTAMINATION FROM GEOTHERMAL FLUID RELEASES

EPA Science Inventory

This report provides analytical methods and graphical techniques to predict potential ground water contamination from geothermal energy development. Overflows and leaks from ponds, pipe leaks, well blowouts, leaks from well casing, and migration from injection zones can be handle...

Comparative Risk Assessment of spill response options for a deepwater oil well blowout: Part 1. Oil spill modeling.

PubMed

French-McCay, Deborah; Crowley, Deborah; Rowe, Jill J; Bock, Michael; Robinson, Hilary; Wenning, Richard; Walker, Ann Hayward; Joeckel, John; Nedwed, Tim J; Parkerton, Thomas F

2018-06-01

Oil spill model simulations of a deepwater blowout in the Gulf of Mexico De Soto Canyon, assuming no intervention and various response options (i.e., subsea dispersant injection SSDI, in addition to mechanical recovery, in-situ burning, and surface dispersant application) were compared. Predicted oil fate, amount and area of surfaced oil, and exposure concentrations in the water column above potential effects thresholds were used as inputs to a Comparative Risk Assessment to identify response strategies that minimize long-term impacts. SSDI reduced human and wildlife exposure to volatile organic compounds; dispersed oil into a large water volume at depth; enhanced biodegradation; and reduced surface water, nearshore and shoreline exposure to floating oil and entrained/dissolved oil in the upper water column. Tradeoffs included increased oil exposures at depth. However, since organisms are less abundant below 200 m, results indicate that overall exposure of valued ecosystem components was minimized by use of SSDI. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparative risk assessment of spill response options for a deepwater oil well blowout: Part III. Stakeholder engagement.

PubMed

Walker, Ann Hayward; Scholz, Debra; McPeek, Melinda; French-McCay, Deborah; Rowe, Jill; Bock, Michael; Robinson, Hilary; Wenning, Richard

2018-05-25

This paper describes oil spill stakeholder engagement in a recent comparative risk assessment (CRA) project that examined the tradeoffs associated with a hypothetical offshore well blowout in the Gulf of Mexico, with a specific focus on subsea dispersant injection (SSDI) at the wellhead. SSDI is a new technology deployed during the Deepwater Horizon (DWH) oil spill response. Oil spill stakeholders include decision makers, who will consider whether to integrate SSDI into future tradeoff decisions. This CRA considered the tradeoffs associated with three sets of response strategies: (1) no intervention; (2) mechanical recovery, in-situ burning, and surface dispersants; and, (3) SSDI in addition to responses in (2). For context, the paper begins with a historical review of U.S. policy and engagement with oil spill stakeholders regarding dispersants. Stakeholder activities throughout the project involved decision-maker representatives and their advisors to inform the approach and consider CRA utility in future oil spill preparedness. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characteristics of a trapped-vortex (TV) combustor

NASA Technical Reports Server (NTRS)

Hsu, K.-Y.; Gross, L. P.; Trump, D. D.; Roquemore, W. M.

1994-01-01

The characteristics of a Trapped-Vortex (TV) combustor are presented. A vortex is trapped in the cavity established between two disks mounted in tandem. Fuel and air are injected directly into the cavity in such a way as to increase the vortex strength. Some air from the annular flow is also entrained into the recirculation zone of the vortex. Lean blow-out limits of the combustor are determined for a wide range of annular air flow rates. These data indicate that the lean blow-out limits are considerably lower for the TV combustor than for flames stabilized using swirl or bluff-bodies. The pressure loss through the annular duct is also low, being less than 2% for the flow conditions in this study. The instantaneous shape of the recirculation zone of the trapped vortex is measured using a two-color PIV technique. Temperature profiles obtained with CARS indicate a well mixed recirculation zone and demonstrate the impact of primary air injection on the local equivalence ratio.

High-pressure jet cutters improve capping operations

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

Abel, L.W.; Campbell, P.J.; Bowden, J.R. Sr.

1995-05-08

Advances in abrasive cutting technology have improved the methods for removing damaged equipment and preparing wellheads for capping. This technology, much of which was refined during well control operations in Kuwait in 1991, can improve the safety and efficiency of capping jobs by cutting wellheads or casing quickly and cleanly. The majority of well control jobs involve one of three types of capping operations: capping to a flange, capping by installing a wellhead, or capping to a casing stub. Capping operations are often the first major step in regaining control of the well during blowout intervention. Proper planning of amore » capping operation must take into account the mass flow rate, combustible nature of the flow, well bore geometry, and operations in the post-capping phase of the project. The paper discusses capping vehicles, tree removal, jet cutters, capping to a flange, capping to a stub, swallowing the stub, spin-on technique, capping on fire, stinging, offshore blowouts, firefighting, pollution control, intervention equipment, and rig removal.« less

Delayed Development of Brain Abscesses Following Stent-Graft Placement in a Head and Neck Cancer Patient Presenting with Carotid Blowout Syndrome

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

Oweis, Yaseen; Gemmete, Joseph J., E-mail: gemmete@umich.edu; Chaudhary, Neeraj

2011-02-15

We describe the delayed development of intracranial abscesses following emergent treatment with a covered stent-graft for carotid blowout syndrome (CBS) in a patient with head and neck cancer. The patient presented with hemoptysis and frank arterial bleeding through the tracheostomy site. A self-expandable stent-graft was deployed across a small pseudoaneurysm arising from the right common carotid artery (RCCA) and resulted in immediate hemostasis. Three months later, the patient suffered a recurrent hemorrhage. CT of the neck demonstrated periluminal fluid around the caudal aspect of the stent-graft with intraluminal thrombus and a small pseudoaneurysm. Subsequently, the patient underwent a balloon testmore » occlusion study and endovascular sacrifice of the RCCA and right internal carotid artery. MRI of the brain demonstrated at least four ring-enhancing lesions within the right cerebral hemisphere consistent with intracranial abscesses that resolved with broad-spectrum antibiotic coverage.« less

The Expansion of the Pulmonary Rib Cage during Breath Stacking Is Influenced by Age in Obese Women

PubMed Central

Barcelar, Jacqueline de Melo; Aliverti, Andrea; Rattes, Catarina; Ximenes, Maria Eduarda; Campos, Shirley Lima; Brandão, Daniella Cunha; Fregonezi, Guilherme; de Andrade, Armèle Dornelas

2014-01-01

Objective To analyze in obese women the acute effects of the breath stacking technique on thoraco-abdominal expansion. Design and Methods Nineteen obese women (BMI≥30 kg/m2) were evaluated by anthropometry, spirometry and maximal respiratory muscle pressures and successively analyzed by Opto-Electronic Plethysmography and a Wright respirometer during quiet breathing and breath stacking maneuvers and compared with a group of 15 normal-weighted healthy women. The acute effects of the maneuvers were assessed in terms of total and compartmental chest wall volumes at baseline, end of the breath stacking maneuver and after the maneuver. Obese subjects were successively classified into two groups, accordingly to the response during the maneuver, group 1 = prevalent rib cage or group 2 = abdominal expansion. Results Age was significantly lower in group 1 than group 2. When considering the two obese groups, FEV1 was lower and minute ventilation was higher only in group 2 compared to controls group. During breath stacking, inspiratory capacity was significant differences in obese subjects with a smaller expansion of the pulmonary rib cage and a greater expansion of the abdomen compared to controls and also between groups 1 and 2. A significant inverse linear relationship was found between age and inspiratory capacity of the pulmonary rib cage but not of the abdomen. Conclusions In obese women the maximal expansion of the rib cage and abdomen is influenced by age and breath stacking maneuver could be a possible therapy for preventing respiratory complications. PMID:25372469

Microgravity

NASA Image and Video Library

1997-01-01

Image taken during a ground based investigation of a methane-fueled laminar flame surrounded by co-flowing air. The flame was enclosed in a chamber, and the pressure reduced. As the pressure decreased, the velocity of the flow increased, causing the flame to change from a stabilized condition to near blow-out or extinction.

COST EFFECTIVE CONTROL OF HEXAVALENT CHROMIUM AIR EMISSIONS FROM FUNCTIONAL CHROMIUM ELECTROPLATING

EPA Science Inventory

This paper will summrize thie pollution prevention (p2) method to control stack emissions from hard chromium plating operations performed by the USEPA's National Risk Management Research Laboratory (NRMRL) over the last four years. During literature research and user surveys, it...

Heated transportable fuel cell cartridges

DOEpatents

Lance, Joseph R.; Spurrier, Francis R.

1985-01-01

A fuel cell stack protective system is made where a plurality of fuel cells, each containing liquid electrolyte subject to crystallization, is enclosed by a containing vessel, and where at least one electric heater is placed in the containing vessel and is capable of preventing electrolyte crystallization.

Tips for Working with ADHD Students of All Ages.

ERIC Educational Resources Information Center

Robelia, Beth

1997-01-01

Tips for working with students who have attention deficit hyperactivity disorder include putting them in charge of something, providing structure, giving feedback, using logical consequences for unwanted behavior, being patient, teaching in novel ways, helping them with their gear, pairing them with another student, allowing blow-out time, and…

75 FR 64348 - BOEMRE Information Collection Activity: 1010-0182, Increased Safety Measures for Energy...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-19

... No. BOEM-2010-0052] BOEMRE Information Collection Activity: 1010-0182, Increased Safety Measures for... the likelihood of blowouts, loss of well control, fires, spillages, physical obstruction to other... subsequent oil spill in the Gulf of Mexico. These events highlight the importance of ensuring safe operations...

78 FR 10685 - Reports, Forms, and Recordkeeping Requirements: Agency Information Collection Activity Under OMB...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-14

... Traffic Safety Administration Title: Tire Pressure Monitoring Systems Special Studies. OMB Number: 2174...: Improperly inflated tires pose a safety risk, increasing the chance of skidding, hydroplaning, longer stopping distances, and crashes due to flat tires and blowouts. In an effort to decrease the number of...

Distribution, morphometry and land use of Delmarva bays

USDA-ARS?s Scientific Manuscript database

Delmarva Bays are depressional wetlands that are elliptical in shape with sandy rims, and occur mainly in the central portion of the Delmarva Peninsula within the Mid-Atlantic United States. It is postulated that they began as wind blowouts during the Pleistocene that filled with water and became e...

Evidence of sulfate-dependent anaerobic methane oxidation within an area impacted by coalbed methane-related gas migration

EPA Science Inventory

The rapid development of unconventional gas resources has been accompanied by an increase in public awareness regarding the potential effects of drilling operations on drinking water sources. Incidents have been reported involving blowouts (e.g., Converse County, WY; Lawrence Tow...

Piezoelectrically Initiated Pyrotechnic Igniter

NASA Technical Reports Server (NTRS)

Quince, Asia; Dutton, Maureen; Hicks, Robert; Burnham, Karen

2013-01-01

This innovation consists of a pyrotechnic initiator and piezoelectric initiation system. The device will be capable of being initiated mechanically; resisting initiation by EMF, RF, and EMI (electromagnetic field, radio frequency, and electromagnetic interference, respectively); and initiating in water environments and space environments. Current devices of this nature are initiated by the mechanical action of a firing pin against a primer. Primers historically are prone to failure. These failures are commonly known as misfires or hang-fires. In many cases, the primer shows the dent where the firing pin struck the primer, but the primer failed to fire. In devices such as "T" handles, which are commonly used to initiate the blowout of canopies, loss of function of the device may result in loss of crew. In devices such as flares or smoke generators, failure can result in failure to spot a downed pilot. The piezoelectrically initiated ignition system consists of a pyrotechnic device that plugs into a mechanical system (activator), which on activation, generates a high-voltage spark. The activator, when released, will strike a stack of electrically linked piezo crystals, generating a high-voltage, low-amperage current that is then conducted to the pyro-initiator. Within the initiator, an electrode releases a spark that passes through a pyrotechnic first-fire mixture, causing it to combust. The combustion of the first-fire initiates a primary pyrotechnic or explosive powder. If used in a "T" handle, the primary would ramp the speed of burn up to the speed of sound, generating a shock wave that would cause a high explosive to go "high order." In a flare or smoke generator, the secondary would produce the heat necessary to ignite the pyrotechnic mixture. The piezo activator subsystem is redundant in that a second stack of crystals would be struck at the same time with the same activation force, doubling the probability of a first strike spark generation. If the first activation fails to ignite, the device is capable of multiple attempts. Another unique aspect is in the design of the pyrotechnic device. There is an electrode that aids the generation of a directed spark and the use of a conductive matrix to support the first-fire material so that the spark will penetrate to the second electrode.

29 CFR 1926.250 - General requirements for storage.

Code of Federal Regulations, 2010 CFR

2010-07-01

... in tiers shall be stacked, racked, blocked, interlocked, or otherwise secured to prevent sliding, falling or collapse. (2) Maximum safe load limits of floors within buildings and structures, in pounds per..., tanks, and similar storage areas shall be equipped with personal fall arrest equipment meeting the...

Development and Application of HVOF Sprayed Spinel Protective Coating for SOFC Interconnects

NASA Astrophysics Data System (ADS)

Thomann, O.; Pihlatie, M.; Rautanen, M.; Himanen, O.; Lagerbom, J.; Mäkinen, M.; Varis, T.; Suhonen, T.; Kiviaho, J.

2013-06-01

Protective coatings are needed for metallic interconnects used in solid oxide fuel cell (SOFC) stacks to prevent excessive high-temperature oxidation and evaporation of chromium species. These phenomena affect the lifetime of the stacks by increasing the area-specific resistance (ASR) and poisoning of the cathode. Protective MnCo2O4 and MnCo1.8Fe0.2O4 coatings were applied on ferritic steel interconnect material (Crofer 22 APU) by high velocity oxy fuel spraying. The substrate-coating systems were tested in long-term exposure tests to investigate their high-temperature oxidation behavior. Additionally, the ASRs were measured at 700 °C for 1000 h. Finally, a real coated interconnect was used in a SOFC single-cell stack for 6000 h. Post-mortem analysis was carried out with scanning electron microscopy. The deposited coatings reduced significantly the oxidation of the metal, exhibited low and stable ASR and reduced effectively the migration of chromium.

Screening charge localization at LiNbO{sub 3} surface with Schottky junction

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

Nagata, Takahiro, E-mail: NAGATA.Takahiro@nims.go.jp; Chikyow, Toyohiro; Kitamura, Kenji

2016-04-25

Screening charge localization was demonstrated by using a Schottky contact with LiNbO{sub 3} (LN). A Cr/LN stack structure with a 2 μm diameter hole array penetrating the Cr layer localized the screening charge of LN in the hole, although the Al/LN stack structure exhibited no surface charge localization behavior. X-ray photoelectron spectroscopy revealed that Cr formed a Schottky contact with LN, which prevents the screening charge from escaping from the hole arrays. The screening charge localization was enhanced by inserting SiO{sub 2} between the metal and LN, which moved the position of the Fermi level to mid gap.

Instability of a witness bunch in a plasma bubble

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

Burov, A.; Lebedev, V.; Nagaitsev, S.

2016-02-16

The stability of a trailing witness bunch, accelerated by a plasma wake accelerator (PWA) in a blow-out regime, is discussed. The instability growth rate as well as the energy spread, required for BNS damping, are obtained. A relationship between the PWA power efficiency and the BNS energy spread is derived.

Effect of Spray Cone Angle on Flame Stability in an Annular Gas Turbine Combustor

NASA Astrophysics Data System (ADS)

Mishra, R. K.; Kumar, S. Kishore; Chandel, Sunil

2016-04-01

Effect of fuel spray cone angle in an aerogas turbine combustor has been studied using computational fluid dynamics (CFD) and full-scale combustor testing. For CFD analysis, a 22.5° sector of an annular combustor is modeled and the governing equations are solved using the eddy dissipation combustion model in ANSYS CFX computational package. The analysis has been carried out at 125 kPa and 303 K inlet conditions for spray cone angles from 60° to 140°. The lean blowout limits are established by studying the behavior of combustion zone during transient engine operation from an initial steady-state condition. The computational study has been followed by testing the practical full-scale annular combustor in an aerothermal test facility. The experimental result is in a good agreement with the computational predictions. The lean blowout fuel-air ratio increases as the spray cone angle is decreased at constant operating pressure and temperature. At higher spray cone angle, the flame and high-temperature zone moves upstream close to atomizer face and a uniform flame is sustained over a wide region causing better flame stability.

Lean stability augmentation study. [on gas turbine combustion chambers

NASA Technical Reports Server (NTRS)

Mcvey, J. B.; Kennedy, J. B.

1979-01-01

An analytical conceptual design study and an experimental test program were conducted to investigate techniques and develop technology for improving the lean combustion limits of premixing, prevaporizing combustors applicable to gas turbine engine main burners. The use of hot gas pilots, catalyzed flameholder elements, and heat recirculation to augment lean stability limits was considered in the conceptual design study. Tests of flameholders embodying selected concepts were conducted at a pressure of 10 arm and over a range of entrance temperatures simulating conditions to be encountered during stratospheric cruise. The tests were performed using an axisymmetric flametube test rig having a nominal diameter of 10.2 cm. A total of sixteen test configurations were examined in which lean blowout limits, pollutant emission characteristics, and combustor performance were evaluated. The use of a piloted perforated plate flameholder employing a pilot fuel flow rate equivalent to 4 percent of the total fuel flow at a simulated cruise condition resulted in a lean blowout equivalence ratio of less than 0.25 with a design point (T sub zero = 600k, Phi = 0.6) NOx emission index of less than 1.0 g/kg.

Macromolecular differentiation of Golgi stacks in root tips of Arabidopsis and Nicotiana seedlings as visualized in high pressure frozen and freeze-substituted samples

NASA Technical Reports Server (NTRS)

Staehelin, L. A.; Giddings, T. H. Jr; Kiss, J. Z.; Sack, F. D.

1990-01-01

The plant root tip represents a fascinating model system for studying changes in Golgi stack architecture associated with the developmental progression of meristematic cells to gravity sensing columella cells, and finally to "young" and "old", polysaccharide-slime secreting peripheral cells. To this end we have used high pressure freezing in conjunction with freeze-substitution techniques to follow developmental changes in the macromolecular organization of Golgi stacks in root tips of Arabidopsis and Nicotiana. Due to the much improved structural preservation of all cells under investigation, our electron micrographs reveal both several novel structural features common to all Golgi stacks, as well as characteristic differences in morphology between Golgi stacks of different cell types. Common to all Golgi stacks are clear and discrete differences in staining patterns and width of cis, medial and trans cisternae. Cis cisternae have the widest lumina (approximately 30 nm) and are the least stained. Medial cisternae are narrower (approximately 20 nm) and filled with more darkly staining products. Most trans cisternae possess a completely collapsed lumen in their central domain, giving rise to a 4-6 nm wide dark line in cross-sectional views. Numerous vesicles associated with the cisternal margins carry a non-clathrin type of coat. A trans Golgi network with clathrin coated vesicles is associated with all Golgi stacks except those of old peripheral cells. It is easily distinguished from trans cisternae by its blebbing morphology and staining pattern. The zone of ribosome exclusion includes both the Golgi stack and the trans Golgi network. Intercisternal elements are located exclusively between trans cisternae of columella and peripheral cells, but not meristematic cells. In older peripheral cells only trans cisternae exhibit slime-related staining. Golgi stacks possessing intercisternal elements also contain parallel rows of freeze-fracture particles in their trans cisternal membranes. We propose that intercisternal elements serve as anchors of enzyme complexes involved in the synthesis of polysaccharide slime molecules to prevent the complexes from being dragged into the forming secretory vesicles by the very large slime molecules. In addition, we draw attention to the similarities in composition and apparent site of synthesis of xyloglucans and slime molecules.

Efficient barrier for charge injection in polyethylene by silver nanoparticles/plasma polymer stack

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

Milliere, L.; Makasheva, K., E-mail: kremena.makasheva@laplace.univ-tlse.fr; Laurent, C.

2014-09-22

Charge injection from a metal/insulator contact is a process promoting the formation of space charge in polymeric insulation largely used in thick layers in high voltage equipment. The internal charge perturbs the field distribution and can lead to catastrophic failure either through its electrostatic effects or through energetic processes initiated under charge recombination and/or hot electrons effects. Injection is still ill-described in polymeric insulation due to the complexity of the contact between the polymer chains and the electrodes. Barrier heights derived from the metal work function and the polymer electronic affinity do not provide a good description of the measurementsmore » [Taleb et al., IEEE Trans. Dielectr. Electr. Insul. 20, 311–320 (2013)]. Considering the difficulty to describe the contact properties and the need to prevent charge injection in polymers for high voltage applications, we developed an alternative approach by tailoring the interface properties by the silver nanoparticles (AgNPs)/plasma polymer stack, deposited on the polymer film. Due to their small size, the AgNPs, covered by a very thin film of plasma polymer, act as deep traps for the injected charges thereby stabilizing the interface from the point of view of charge injection. After a quick description of the method for elaborating the nanostructured layer near the contact, it is demonstrated how the AgNPs/plasma polymer stack effectively prevents, in a spectacular way, the formation of bulk space charge.« less

Tensile Response of Hoop Reinforced Multiaxially Braided Thin Wall Composite Tubes

NASA Astrophysics Data System (ADS)

Roy, Sree Shankhachur; Potluri, Prasad; Soutis, Constantinos

2017-04-01

This paper presents the tensile response of thin-walled composite tubes with multi-axial fibre architecture. A hybrid braid-wound layup has the potential to optimise the composite tube properties, however, stacking sequence plays a role in the failure mechanism. A braid-winding method has been used to produce stacked overwound braid layup [(±45°/0°)5/90°4]T. Influence of stacking sequence on premature failure of hoop layers has been reported. Under tensile loading, a cross-ply composite tube with the alternate stacking of hoop and axial fibre show hoop plies splitting similar to the overwound braided composite tube. However, splitting has been restricted by the surrounding axial plies and contained between the adjacent axial fibre tows. This observation suggests hoop layers sandwiched between braid layers will improve structural integrity. A near net shape architecture with three fibre orientation in a triaxial braid will provide additional support to prevent extensive damage for plies loaded in off-axis. Several notable observations for relatively open braid structures such as tow scissoring, high Poisson's ratio and influence of axial tow crimp on the strain to failure have been reported. Digital Image Correlation (DIC) in conjunction with surface strain gauging has been employed to capture the strain pattern.

Risk of Carotid Blowout After Reirradiation of the Head and Neck: A Systematic Review

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

McDonald, Mark W., E-mail: mwmcdona@iupui.edu; Indiana University Health Proton Therapy Center, Bloomington, IN; Moore, Michael G.

2012-03-01

Purpose: Carotid blowout (CB) is a rare but frequently fatal complication of head-and-neck (H and N) cancer or its treatment. We sought to determine the reported rate of CB in patients receiving salvage reirradiation for H and N cancer. Methods and Materials: A literature search identified 27 published articles on H and N reirradiation involving 1554 patients, and a pooled analysis was performed to determine the rate of CB. Treatment parameters, including prior radiation dose, interval from prior radiation, dose and fractionation of reirradiation, use of salvage surgery, and chemotherapy, were abstracted and summarized. The cumulative risk of CB wasmore » compared between groups using Fisher's exact test. Results: Among 1554 patients receiving salvage H and N reirradiation, there were 41 reported CBs, for a rate of 2.6%; 76% were fatal. In patients treated in a continuous course with 1.8-2-Gy daily fractions or 1.2-Gy twice-daily fractions, 36% of whom received concurrent chemotherapy, the rate of CB was 1.3%, compared with 4.5% in patients treated with 1.5 Gy twice daily in alternating weeks or with delayed accelerated hyperfractionation, all of whom received concurrent chemotherapy (p = 0.002). There was no statistically significant difference in the rate of CB between patients treated with or without concurrent chemotherapy, or between patients treated with or without salvage surgery before reirradiation. Conclusion: Carotid blowout is an infrequent but serious complication of salvage reirradiation for H and N cancer. The rate of CB was lower among patients treated with conventional or hyperfractionated schedules compared with regimens of accelerated hyperfractionation, though heterogeneous patient populations and treatment parameters preclude definite conclusions. Given the high mortality rate of CB, discussion of the risk of CB is an important component of informed consent for salvage reirradiation.« less

Solid oxidized fuel cells seals leakage setup and testing

NASA Technical Reports Server (NTRS)

Bastrzyk, Marta B.

2004-01-01

As the world s reserves of fossil fuels are depleted, the U.S. Government, as well as other countries and private industries, is researching solutions for obtaining power, answers that would be more efficient and environmentally friendly. For a long time engineers have been trying to obtain the benefits of clean electric power without heavy batteries or pollution-producing engines. While some of the inventions proved to be effective (i.e. solar panels or windmills) their applications are limited due to dependency on the energy source (i.e. sun or wind). Currently, as energy concerns increase, research is being carried out on the development of a Solid Oxide Fuel Cell (SOFC). The United States government is taking a proactive role in expanding the technology through the Solid State Energy Conversion Alliance (SECA) Program, which is coordinated by the Department of Energy. into an electrical energy. This occurs by the means of natural tendency of oxygen and hydrogen to chemically react. While controlling the process, it is possible to harvest the energy given off by the reaction. SOFCs use currently available fossil fuels and convert a variety of those fuels with very high efficiency (about 40% more efficient than modem thermal power plants). At the same time they are almost entirely nonpolluting and due to their size they can be placed in remote areas. The main fields where the application of the fuel cells appears to be the most useful for are stationary energy sources, transportation, and military applications. structure and materials must be resolved. All the components must be operational in harsh environments including temperatures reaching 800 C and cyclic thermal- mechanical loading. Under these conditions, the main concern is the requirement for hermetic seals to: (1) prevent mixing of the fuel and oxidant within the stack, (2) prevent parasitic leakage of the fuel from the stack, (3) prevent contamination of the anode by air leaking into the stack, (4) electrically isolate the individual cells within the stack, and (5) mechanically bond the cell components. The sealing challenges are aggravated by the need to maintain hermetic boundaries between the different flow paths within the fuel cell throughout cycled operation. Within the timeframe of my tenure, the main objective is to assist in building a state-of-art test facility.

Native and sodium dodecyl sulfate-capillary gel electrophoresis of proteins on a single microchip.

PubMed

Tsai, Shuo-Wen; Loughran, Michael; Suzuki, Hiroaki; Karube, Isao

2004-02-01

Simultaneous electrophoresis of both native and Sodium dodecyl sulfate (SDS) proteins was observed on a single microchip within 20 min. The capillary array prevented lateral diffusion of SDS components and avoided cross contamination of native protein samples. The planar sputtered electrode format provided a more uniform distribution of separation voltage into each of the 36 parallel microchannel capillaries than platinum wire electrodes commonly used in conventional electrophoresis. The customized geometry of the stacking capillary machined into the cover plate of the microchip facilitated reproducible sample injection without the requirement for stacking gel. Polyimide served as a mask and facilitated insulation of the anode and cathode to prevent electrode lift off and deterioration during continuous electrophoresis, even at a constant current of 8 mA. Improved protein separation was observed during capillary electrophoresis at lower currents. Ferguson plot analysis confirmed the electrophoretic mobility of native globular proteins in accordance with their charge and size. Corresponding Ferguson plot analysis of SDS-associated proteins on the same chip confirmed separation of marker proteins according to their molecular weight.

Design of hydrogen vent line for the cryogenic hydrogen system in J-PARC

NASA Astrophysics Data System (ADS)

Tatsumoto, Hideki; Aso, Tomokazu; Kato, Takashi; Ohtsu, Kiichi; Hasegawa, Shoichi; Maekawa, Fujio; Futakawa, Masatoshi

2009-02-01

As one of the main experimental facilities in J-PARC, an intense spallation neutron source (JSNS) driven by a 1-MW proton beam selected supercritical hydrogen at a temperature of 20 K and a pressure of 1.5 MPa as a moderator material. Moderators are controlled by a cryogenic hydrogen system that has a hydrogen relief system, which consists of high and low pressure stage of manifolds, a hydrogen vent line and a stack, in order to release hydrogen to the outside safely. The design of the hydrogen vent line should be considered to prevent purge nitrogen gas in the vent line from freezing when releasing the cryogenic hydrogen, to prevent moisture in the stack placed in an outdoor location from freezing, and to inhibit large piping temperature reduction at a building wall penetration. In this work, temperature change behaviors in the hydrogen vent line were analyzed by using a CFD code, STAR-CD. We determined required sizes of the vent line based on the analytical results and its layout in the building.

Adhesion enhancement methods for a roll-to-sheet fabrication process of DE stack-transducers and their influences on the electric properties

NASA Astrophysics Data System (ADS)

Bochmann, Helge; von Heckel, Benedikt; Maas, Jürgen

2017-04-01

Transducers made of dielectric elastomers (DE) offer versatile opportunities for many different applications. To gain large strains and forces a multilayer topology is commonly used. DE stack-transducers represent one multilayer topology and can be operated as a sensor, a generator or an actuator simultaneously. They are made of many layers of DE films, like silicone (PDMS) and polyurethane (PUR), stacked on top of each other. The single layers are several micrometers thin and coated with a compliant electrode on both sides. Depending on the application a DE transducer has to withstand tensile forces, which may lead to a delamination of the layers and a ripping of the stack-transducer. This can be prevented by enhancing the adhesion among the layers. Within this contribution a surface plasma jet treatment with an atmospheric plasma beam as well as an adhesive utilized as electrode material was investigated to obtain an adhesion enhancement. The effects of these methods to enhance the adhesion are introduced briefly. Furthermore, various investigations were made to determine the benefits of the enhancement methods with respect to the electromechanical properties of the electrode. Therefore, certain tests regarding the surface resistance of the electrode and the dielectric breakdown strength (DBS) of the DE film were conducted. The tests indicate that the influences are strongly dependent on the composition of the electrode and the used DE material. Finally, improvements for a dry deposition roll-to-sheet manufacturing process for DE stack-transducers are derived from the obtained results.

78 FR 72693 - Information Collection Activities: Application for Permit To Modify; Proposed Collection; Comment...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-03

... natural gas resources in a manner that is consistent with the need to make such resources available to... minimize the likelihood of blowouts, loss of well control, fires, spillages, physical obstructions to other... environment or to property or endanger life or health.'' In addition to the general authority of OCSLA...

Increased Multilayer Fabrication and RF Characterization of a High-Density Stacked MIM Capacitor Based on Selective Etching

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

Tseng, VFG; Xie, HK

2014-07-01

This paper presents the fabrication and characterization of a high-density multilayer stacked metal-insulator-metal (MIM) capacitor based on a novel process of depositing the MIM multilayer on pillars followed by polishing and selective etching steps to form a stacked capacitor with merely three photolithography steps. In this paper, the pillars were made of glass to prevent substrate loss, whereas an oxide-nitride-oxide dielectric was employed for lower leakage, better voltage/frequency linearity, and better stress compensation. MIM capacitors with six dielectric layers were successfully fabricated, yielding capacitance density of 3.8 fF/mu m(2), maximum capacitance of 2.47 nF, and linear and quadratic voltage coefficientsmore » of capacitance below 21.2 ppm/V and 2.31 ppm/V-2. The impedance was measured from 40 Hz to 3 GHz, and characterized by an analytically derived equivalent circuit model to verify the radio frequency applicability. The multilayer stacking-induced plate resistance mismatch and its effect on the equivalent series resistance (ESR) and effective capacitance was also investigated, which can be counteracted by a corrected metal thickness design. A low ESR of 800 m Omega was achieved, whereas the self-resonance frequency was >760 MHz, successfully demonstrating the feasibility of this method to scale up capacitance densities for high-quality-factor, high-frequency, and large-value MIM capacitors.« less

Stable isotope insights into the weathering processes of a phosphogypsum disposal area.

PubMed

Papaslioti, Evgenia-Maria; Pérez-López, Rafael; Parviainen, Annika; Macías, Francisco; Delgado-Huertas, Antonio; Garrido, Carlos J; Marchesi, Claudio; Nieto, José M

2018-04-28

Highly acidic phosphogypsum wastes with elevated potential for contaminant leaching are stack-piled near coastal areas worldwide, threatening the adjacent environment. Huge phosphogypsum stacks were disposed directly on the marshes of the Estuary of Huelva (SW Spain) without any impermeable barrier to prevent leaching and thus, contributing to the total contamination of the estuarine environment. According to the previous weathering model, the process water ponded on the surface of the stack, initially used to carry the waste, was thought to be the main washing agent through its infiltration and subsequently the main component of the leachates emerging as the edge outflows. Preliminary restorations have been applied to the site and similar ones are planned for the future considering process water as the only pollution agent. Further investigation to validate the pollution pathway was necessary, thus an evaluation of the relationship between leachates and weathering agents of the stack was carried out using stable isotopes (δ 18 O, δ 2 H, and δ 34 S) as geochemical tracers. Quantification of the contribution of all possible end-members to the phosphogypsum leachates was also conducted using ternary mixing via the stable isotopic tracers. The results ruled out ponded process water as main vector of edge outflow pollution and unveiled a continuous infiltration of estuarine waters to the stack implying that is subjected to an open weathering system. The isotopic tracers revealed a progressive contribution downstream from fluvial to marine signatures in the composition of the edge outflows, depending on the location of each disposal zone within the different estuarine morphodynamic domains. Thus, the current study suggests that the access of intertidal water inside the phosphogypsum stack, for instance through secondary tidal channels, is the main responsible for the weathering of the waste in depth, underlying the necessity for new, more effective restorations plans. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Determination of Hydrogen Sulfide in Stack Gases, Iodometric Titration After Sulfite Removal.

ERIC Educational Resources Information Center

Robles, E. G.

The determination of hydrogen sulfide in effluents from coal-fired furnaces and incinerators is complicated by the presence of sulfur oxides (which form acids). Organic compounds also may interfere with or prevent the formation of the cadmium sulfide precipitate or give false positive results because of reaction with iodine. The report presents a…

Desensitizing Flame Structure and Exhaust Emissions to Flow Parameters in an Ultra-Compact Combustor

DTIC Science & Technology

2012-03-22

fuel .... 9 Figure 2.4: UNICORN model of hydrogen in air flame front propagation under the loading condition (a) 10 g’s and (b) 500 g’s...Lean Blowout ...................................................................................8 UNICORN Unsteady Ignition and Combustion with...computationally recreate Lewis’ experimental results. Using the Unsteady Ignition and 9 Combustion with Reactions ( UNICORN ) code, flame propagation

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

Zilkha, A.

Computed tomographic (CT) findings in four patients with isolated blow-out fracture of the medial orbital wall are reported. CT delineated the fracture site and its extent in each case, and clearly demonstrated medial rectus muscle entrapment in two. This was confirmed by surgery. CT was found superior to polytomography and proved to be the best radiologic means for the diagnosis of medial orbital wall fracture and muscle entrapment.

Predicting The Intrusion Layer From Deep Ocean Oil Spills

NASA Astrophysics Data System (ADS)

Wang, Dayang; Chow, Aaron; Adams, E. Eric

2015-11-01

Oil spills from deep ocean blowout events motivate our study of multiphase plumes in a water column. Key to understanding the long-term fate of these plumes is the ability to predict the depth and persistence of intrusion layers. While intrusion layers from multiphase plumes have been studied under stagnant conditions, their behavior in the presence of crossflow, especially in mild crossflow, remains poorly understood. The classical classification of plume behavior identifies two regimes: crossflow-dominant and stratification-dominant--but it does not account for the interplay between the two effects, leaving the transition region unexplored. We conduct laboratory tank experiments to investigate the behavior of intrusion layers under the simultaneous action of crossflow and stratification. Our experiments use an inverted frame of reference, using glass beads with a range of sizes to simulate oil droplets. We find that crossflow creates enhanced mixing, which in turn leads to a shallower intrusion layer of the released fluid (correspondingly, a deeper layer in the case of a deep ocean blowout). We develop a mathematical formulation that extends previous models to account for crossflow effects, and use field observations to validate the analytical and experimental findings.

Reirradiation for second primary or recurrent cancers of the head and neck: Dosimetric and outcome analysis.

PubMed

Garg, Shivank; Kilburn, Jeremy M; Lucas, John T; Randolph, David; Urbanic, James J; Hinson, William H; Kearns, William T; Porosnicu, Mercedes; Greven, Kathryn

2016-04-01

The purpose of this study was to examine outcomes, toxicity, and dosimetric characteristics of patients treated with reirradiation for head and neck cancers. Fifty patients underwent ≥2 courses of radiation therapy (RT) postoperatively or definitively with or without chemotherapy. Composite dose volume histograms (DVHs) for selected anatomic structures were correlated with grade ≥3 late toxicity. Median initial and retreatment radiation dose was 64 and 60 Gy, respectively. Median overall survival (OS), progression-free survival (PFS), and 1-year PFS rates were 18 months, 11 months, and 45%, respectively, with 13 months median follow-up. Thirty-four percent of patients experienced grade ≥3 late toxicity with 1 death from carotid blowout. The DVH corresponding to the carotid blowout fell above the third quartile compared with other patients. Our analysis is the first to systematically evaluate the dose to the carotid artery using composite dosimetry in head and neck reirradiation patients, and demonstrates a promising technique for evaluating the dose to other normal tissue structures. © 2015 Wiley Periodicals, Inc. Head Neck 38: E961-E969, 2016. © 2015 Wiley Periodicals, Inc.

Beyond injection: Trojan horse underdense photocathode plasma wakefield acceleration

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

Hidding, B.; Rosenzweig, J. B.; Xi, Y.

2012-12-21

An overview on the underlying principles of the hybrid plasma wakefield acceleration scheme dubbed 'Trojan Horse' acceleration is given. The concept is based on laser-controlled release of electrons directly into a particle-beam-driven plasma blowout, paving the way for controlled, shapeable electron bunches with ultralow emittance and ultrahigh brightness. Combining the virtues of a low-ionization-threshold underdense photocathode with the GV/m-scale electric fields of a practically dephasing-free beam-driven plasma blowout, this constitutes a 4th generation electron acceleration scheme. It is applicable as a beam brightness transformer for electron bunches from LWFA and PWFA systems alike. At FACET, the proof-of-concept experiment 'E-210: Trojanmore » Horse Plasma Wakefield Acceleration' has recently been approved and is in preparation. At the same time, various LWFA facilities are currently considered to host experiments aiming at stabilizing and boosting the electron bunch output quality via a trojan horse afterburner stage. Since normalized emittance and brightness can be improved by many orders of magnitude, the scheme is an ideal candidate for light sources such as free-electron-lasers and those based on Thomson scattering and betatron radiation alike.« less

ON THE OBSERVATION AND SIMULATION OF SOLAR CORONAL TWIN JETS

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

Liu, Jiajia; Wang, Yuming; Zhang, Quanhao

We present the first observation, analysis, and modeling of solar coronal twin jets, which occurred after a preceding jet. Detailed analysis on the kinetics of the preceding jet reveals its blowout-jet nature, which resembles the one studied in Liu et al. However, the erupting process and kinetics of the twin jets appear to be different from the preceding one. Lacking detailed information on the magnetic fields in the twin jet region, we instead use a numerical simulation using a three-dimensional (3D) MHD model as described in Fang et al., and find that in the simulation a pair of twin jetsmore » form due to reconnection between the ambient open fields and a highly twisted sigmoidal magnetic flux, which is the outcome of the further evolution of the magnetic fields following the preceding blowout jet. Based on the similarity between the synthesized and observed emission, we propose this mechanism as a possible explanation for the observed twin jets. Combining our observation and simulation, we suggest that with continuous energy transport from the subsurface convection zone into the corona, solar coronal twin jets could be generated in the same fashion addressed above.« less

Effects of Fuel Composition on Combustion Stability and NO X Emissions for Traditional and Alternative Jet Fuels

NASA Astrophysics Data System (ADS)

Vijlee, Shazib Z.

Synthetic jet fuels are studied to help understand their viability as alternatives to traditionally derived jet fuel. Two combustion parameters -- flame stability and NOX emissions -- are used to compare these fuels through experiments and models. At its core, this is a fuels study comparing how chemical makeup and behavior relate. Six 'real', complex fuels are studied in this work -- four are synthetic from alternative sources and two are traditional from petroleum sources. Two of the synthetic fuels are derived from natural gas and coal via the Fischer Tropsch catalytic process. The other two are derived from Camelina oil and tallow via hydroprocessing. The traditional military jet fuel, JP8, is used as a baseline as it is derived from petroleum. The sixth fuel is derived from petroleum and is used to study the effects of aromatic content on the synthetic fuels. The synthetic fuels lack aromatic compounds, which are an important class of hydrocarbons necessary for fuel handling systems to function properly. Several single-component fuels are studied (through models and/or experiments) to facilitate interpretation and understanding. The flame stability study first compares all the 'real', complex fuels for blowout. A toroidal stirred reactor is used to try and isolate temperature and chemical effects. The modeling study of blowout in the toroidal reactor is the key to understanding any fuel-based differences in blowout behavior. A detailed, reacting CFD model of methane is used to understand how the reactor stabilizes the flame and how that changes as the reactor approaches blowout. A 22 species reduced form of GRI 3.0 is used to model methane chemistry. The knowledge of the radical species role is utilized to investigate the differences between a highly aliphatic fuel (surrogated by iso-octane) and a highly aromatic fuel (surrogated by toluene). A perfectly stirred reactor model is used to study the chemical kinetic pathways for these fuels near blowout. The differences in flame stabilization can be attributed to the rate at which these fuels are attacked and destroyed by radical species. The slow disintegration of the aromatic rings reduces the radical pool available for chain-initiating and chain-branching, which ultimately leads to an earlier blowout. The NOX study compares JP8, the aromatic additive, the synthetic fuels with and without an aromatic additive, and an aromatic surrogate (1,3,5-trimethylbenzene). A jet stirred reactor is used to try and isolate temperature and chemical effects. The reactor has a volume of 15.8 mL and a residence time of approximately 2.5 ms. The fuel flow rate (hence equivalence ratio) is adjusted to achieve nominally consistent temperatures of 1800, 1850, and 1900K. Small oscillations in fuel flow rate cause the data to appear in bands, which facilitated Arrhenius-type NOX-temperature correlations for direct comparison between fuels. The fuel comparisons are somewhat inconsistent, especially when the aromatic fuel is blended into the synthetic fuels. In general, the aromatic surrogate (1,3,5-trimethylbenzene) produces the most NOX, followed by JP8. The synthetic fuels (without aromatic additive) are always in the same ranking order for NOX production (HP Camelina > FT Coal > FT Natural Gas > HP Tallow). The aromatic additive ranks differently based on the temperature, which appears to indicate that some of the differences in NOX formation are due to the Zeldovich NOX formation pathway. The aromatic additive increases NOX for the HP Tallow and decreases NOX for the FT Coal. The aromatic additive causes increased NOX at low temperatures but decreases NOX at high temperatures for the HP Camelina and FT Natural Gas. A single perfectly stirred reactor model is used with several chemical kinetic mechanisms to study the effects of fuel (and fuel class) on NO X formation. The 27 unique NOX formation reactions from GRI 3.0 are added to published mechanisms for jet fuel surrogates. The investigation first looked at iso-octane and toluene and found that toluene produces more NOX because of a larger pool of O radical. The O radical concentration was lower for iso-octane because of an increased concentration of methyl (CH 3) radical that consumes O radical readily. Several surrogate fuels (iso-octane, toluene, propylcyclohexane, n-octane, and 1,3,5-trimethylbenzene) are modeled to look for differences in NOX production. The trend (increased CH3 → decreased O → decreased NOX) is consistently true for all surrogate fuels with multiple kinetic mechanisms. It appears that the manner in which the fuel disintegrates and creates methyl radical is an extremely important aspect of how much NOX a fuel will produce. (Abstract shortened by UMI.).

Linear particle accelerator with seal structure between electrodes and insulators

DOEpatents

Broadhurst, John H.

1989-01-01

An electrostatic linear accelerator includes an electrode stack comprised of primary electrodes formed or Kovar and supported by annular glass insulators having the same thermal expansion rate as the electrodes. Each glass insulator is provided with a pair of fused-in Kovar ring inserts which are bonded to the electrodes. Each electrode is designed to define a concavo-convex particle trap so that secondary charged particles generated within the accelerated beam area cannot reach the inner surface of an insulator. Each insulator has a generated inner surface profile which is so configured that the electrical field at this surface contains no significant tangential component. A spark gap trigger assembly is provided, which energizes spark gaps protecting the electrodes affected by over voltage to prevent excessive energy dissipation in the electrode stack.

Proceedings of the Conference on Birth Defects for Educators (May 4, 1978).

ERIC Educational Resources Information Center

Davidson, Michael S., Ed.; Davidson, Mary W., Ed.

Six papers from a 1978 conference on birth defects focus on prevention. G. Stickle ("The Health of America's Babies: How Do We Stack Up?'" reviews risk in pregnancy, cites inadequate prenatal care and maternal nutrition, and discusses examples of how the United States is not applying its knowledge of how to improve pregnancy outcome. In "Genetic…

Dispersant Effectiveness, In-Situ Droplet Size Distribution and Numerical Modeling to Assess Subsurface Dispersant Injection as a Deepwater Blowout Oil Spill Response Option and Evaluation of Oil Fluorescence Characteristics to Improve Forensic Response Tools

EPA Science Inventory

This report summarizes two projects covered under an Interagency Agreement between the Bureau of Safety and Environmental Enforcement (BSEE) and the U.S. Environmental Protection Agency (EPA) in collaboration with the Bedford Institute of Oceanography, Department of Fisheries and...

Demography and monitoring of Welsh's milkweed (Asclepias welshii) at Coral Pink Sand Dunes

Treesearch

Brent C. Palmer; L. Armstrong

2001-01-01

Results are presented of a 12-year monitoring program on the Coral Pink Sand Dunes and Sand Hills populations of the threatened Welsh's milkweed, Asclepias welshii N & P Holmgren. The species is an early sera1 member of the dune flora, colonizing blowouts and advancing with shifting dunes. When an area stabilizes and other vegetation encroaches, A. welshii is...

77 FR 11158 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-24

... Notice is hereby given that on February 17, 2012, a proposed Consent Decree in In Re: Oil Spill by the Oil Rig ``Deepwater Horizon'' in the Gulf of Mexico, on April 20, 2010, MDL 2179, was lodged with the... discharge of oil into the Gulf of Mexico resulting from the April 20, 2010 blowout of the Macondo well and...

The History All around Us: Roosevelt High School and the 1968 Eastside Blowouts

ERIC Educational Resources Information Center

Gibbs, Brian C.

2011-01-01

A text can be anything: a poem, a map, an old letter. To spur great learning, it needs to be provocative, powerful, open to multiple interpretations, and, above all, it needs to teach something profound. A school building can also become text when a teacher uses place as a way to make history come alive. The author discusses how he uses Theodore…

Flame blowout and pollutant emissions in vitiated combustion of conventional and bio-derived fuels

NASA Astrophysics Data System (ADS)

Singh, Bhupinder

The widening gap between the demand and supply of fossil fuels has catalyzed the exploration of alternative sources of energy. Interest in the power, water extraction and refrigeration (PoWER) cycle, proposed by the University of Florida, as well as the desirability of using biofuels in distributed generation systems, has motivated the exploration of biofuel vitiated combustion. The PoWER cycle is a novel engine cycle concept that utilizes vitiation of the air stream with externally-cooled recirculated exhaust gases at an intermediate pressure in a semi-closed cycle (SCC) loop, lowering the overall temperature of combustion. It has several advantages including fuel flexibility, reduced air flow, lower flame temperature, compactness, high efficiency at full and part load, and low emissions. Since the core engine air stream is vitiated with the externally cooled exhaust gas recirculation (EGR) stream, there is an inherent reduction in the combustion stability for a PoWER engine. The effect of EGR flow and temperature on combustion blowout stability and emissions during vitiated biofuel combustion has been characterized. The vitiated combustion performance of biofuels methyl butanoate, dimethyl ether, and ethanol have been compared with n-heptane, and varying compositions of syngas with methane fuel. In addition, at high levels of EGR a sharp reduction in the flame luminosity has been observed in our experimental tests, indicating the onset of flameless combustion. This drop in luminosity may be a result of inhibition of processes leading to the formation of radiative soot particles. One of the objectives of this study is finding the effect of EGR on soot formation, with the ultimate objective of being able to predict the boundaries of flameless combustion. Detailed chemical kinetic simulations were performed using a constant-pressure continuously stirred tank reactor (CSTR) network model developed using the Cantera combustion code, implemented in C++. Results have been presented showing comparative trends in pollutant emissions generation, flame blowout stability, and combustion efficiency. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

In search of thermogenic methane in groundwater in the Netherlands, with emphasis on the location of a historic gas well blowout

NASA Astrophysics Data System (ADS)

Schout, G.; Griffioen, J.; Hassanizadeh, S. M.; Hartog, N.

2017-12-01

Similar to the US, the Netherlands has a long history of oil & gas production, with around 2500 onshore hydrocarbon wells drilled since the late 1930s. While conventional reserves are diminishing, a governmental moratorium was put in place on shale gas exploration and production until 2023, in part due to concerns about its effects on groundwater quality. To investigate the industry's historic and potential future impact on groundwater quality in the country, a study was carried out to assess i) baseline methane concentrations and origin ii) the natural connectivity of deeper gas-bearing layers with the shallower groundwater systems. Through datamining, a dataset consisting of 12,200 groundwater analyses with methane concentrations was assembled. Furthermore, 25 additional samples were collected at targeted locations and analysed for dissolved gas molecular and isotopic composition. Methane concentrations are positively skewed with median, mean and maximum concentrations of 0.28, 2.17 and 120 mg/L, respectively. No correlation between methane concentrations and distance to hydrocarbon wells or faults is observed. In general, concentrations cannot be readily explained by factors such as the depth, geographic location, host formation and depositional environment. Thermogenic methane was first encountered at several hundred meters depth, below thick successions of marine Paleogene and Neogene clays that are present throughout the country and impede vertical flow. All methane encountered above these formations was found to be biogenic in origin, with one notable exception - a sample taken at the site of a catastrophic gas well blowout that occurred in 1965 near the village of Sleen. Combined, these findings suggest that thermogenic methane does not naturally occur in Dutch shallow groundwater and its presence can be used as an indicator of anthropogenic gas leakage. The unique Sleen blowout site was selected for a detailed investigation of the long-term effects of uncontrolled gas leakage on groundwater chemistry. Methane concentrations up to 45 mg/L were observed and the distribution pattern suggests on-going leakage, 50 years after the events. Results also show that anaerobic oxidation of methane plays a major role in controlling the spread of dissolved methane.

The Vibration Ring. Phase 1; [Seedling Fund

NASA Technical Reports Server (NTRS)

Asnani, Vivake M.; Krantz, Timothy L.; Delap, Damon C.; Stringer, David B.

2014-01-01

The vibration ring was conceived as a driveline damping device to prevent structure-borne noise in machines. It has the appearance of a metal ring, and can be installed between any two driveline components like an ordinary mechanical spacer. Damping is achieved using a ring-shaped piezoelectric stack that is poled in the axial direction and connected to an electrical shunt circuit. Surrounding the stack is a metal structure, called the compression cage, which squeezes the stack along its poled axis when excited by radial driveline forces. The stack in turn generates electrical energy, which is either dissipated or harvested using the shunt circuit. Removing energy from the system creates a net damping effect. The vibration ring is much stiffer than traditional damping devices, which allows it to be used in a driveline without disrupting normal operation. In phase 1 of this NASA Seedling Fund project, a combination of design and analysis was used to examine the feasibility of this concept. Several designs were evaluated using solid modeling, finite element analysis, and by creating prototype hardware. Then an analytical model representing the coupled electromechanical response was formulated in closed form. The model was exercised parametrically to examine the stiffness and loss factor spectra of the vibration ring, as well as simulate its damping effect in the context of a simplified driveline model. The results of this work showed that this is a viable mechanism for driveline damping, and provided several lessons for continued development.

Colorimetric stack pad immunoassay for bacterial identification.

PubMed

Eltzov, Evgeni; Marks, Robert S

2017-01-15

A new colorimetric immunoassay concept, utilizing conventional lateral flow membranes (e.g., conjugation, sample, absorption and nitrocellulose), were placed in a different configuration in a stacking manner, where the liquid sample that may contain the analyte diffuses from the bottom to the upper-most layer. The key element of this proprietary technology is a capture layer, where a nitrocellulose membrane is modified with the target analyte of interest, namely in this study target Escherichia coli. During the immunoassay operation, samples contaminated with the target bacteria will conjugate to their corresponding HRP-antibodies laying in wait and the immune-target measurand complex flows by capillarity towards the upper-most layer to generate a colorimetric signal (positive answer) through an enzymatic reaction. In target-free samples, previously immobilized target bacteria on the capture layer will prevent the HRP-labeled anti-target antibodies from migrating to the upper-most layer, where the enzymatic substrate lays in wait. After optimization, the sensitivity of this approach was found to be 1,000 folds higher than ELISAs (10 2 cellsmL -1 ). The advantages of the stacked pad assay include: miniaturization, operational simplicity, fast response time (less than 5min), useful sensitivity. Copyright © 2016 Elsevier B.V. All rights reserved.

Plasma Oxidation Of Silver And Zinc In Low-Emissivity Stacks

NASA Astrophysics Data System (ADS)

Ross, R. C.; Sherman, R.,; Bunger, R. A.; Nadel, S. J.

1987-11-01

The oxidation of silver and zinc films was studied by exposing metallic films to low-power 02 plasmas and analyzing the reacted films. This type of oxidation is an important phenomenon near the barrier layer in sputter-deposited metal-oxide/Ag/metal-oxide low-emissivity (low-e) coatings. Barrier layers generally are deposited on the Ag layer to prevent its degradation during subsequent 02 reactive sputtering. Both individual layers and complete stacks were studied. In addition, the thermal stability of plasma-oxidized Ag was examined. There are several important findings for the individual layers. Ag oxidizes rapidly in the plasma, forming Ag≍1.70 after complete reaction. Relative to the original Ag, the 9ide has -l.7 times greater thick-ness, >10 times higher electrical resistiv-ity (p), and increased surface roughness. Zn oxidizes slowly, at only -1% to 0.1% times the rate for Ag, and is thus more difficult to characterize. The results for individual layers are discussed as they relate to practical pro-perties of low-e stacks: the difficulty of obtaining complete barrier layer oxidation without partially degrading the Ag layer as well as the effects of heat treatment and aging.

Diverter bop system and method for a bottom supported offshore drilling rig

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

Roche, J. R.; Alexander, G. G.; Carbaugh, W. L.

1985-06-25

A system and method for installing a fluid flow controller and telescoping spools beneath an offshore bottom supported drilling rig rotary table is disclosed. Upper and lower telescoping spools are provided for initially connecting a Diverter/BOP convertible fluid flow controller between structural casing in the well and a permanent housing beneath the drilling rig rotary table. Clamp means are provided for clamping the rig vent line to an opening in the housing wall of the fluid flow controller during drilling of the borehole through the structural casing in preparation for setting and cementing the conductor casing. In that mode, themore » system is adapted as a diverter system. After the well is drilled for the conductor casing and the conductor casing is cemented and cut off at its top, a mandrel is fitted at the top of the conductor casing to which the lower end of the lower spool may be connected. The system may be used in this configuration as a diverter system, or after removal of the vent line and connection of a kill line to the housing outlet, the system may be used as a low pressure blowout preventer system.« less

Shape memory alloy actuated accumulator for ultra-deepwater oil and gas exploration

NASA Astrophysics Data System (ADS)

Patil, Devendra; Song, Gangbing

2016-04-01

As offshore oil and gas exploration moves further offshore and into deeper waters to reach hydrocarbon reserves, it is becoming essential for the industry to develop more reliable and efficient hydraulic accumulators to supply pressured hydraulic fluid for various control and actuation operations, such as closing rams of blowout preventers and controlling subsea valves on the seafloor. By utilizing the shape memory effect property of nitinol, which is a type of shape memory alloy (SMA), an innovative SMA actuated hydraulic accumulator prototype has been developed and successfully tested at Smart Materials and Structure Laboratory at the University of Houston. Absence of gas in the developed SMA accumulator prototype makes it immune to hydrostatic head loss caused by water depth and thus reduces the number of accumulators required in deep water operations. Experiments with a feedback control have demonstrated that the proposed SMA actuated accumulator can provide precisely regulated pressurized fluids. Furthermore the potential use of ultracapacitors along with an embedded system to control the electric power supplied to SMA allows this accumulator to be an autonomous device for deployment. The developed SMA accumulator will make deepwater oil extraction systems more compact and cost effective.

What happens between pure hydraulic and buckling mechanisms of blowout fractures?

PubMed

Nagasao, Tomohisa; Miyamoto, Junpei; Shimizu, Yusuke; Jiang, Hua; Nakajima, Tatsuo

2010-06-01

The present study aims to evaluate how the ratio of the hydraulic and buckling mechanisms affects blowout fracture patterns, when these two mechanisms work simultaneously. Three-dimensional computer-aided-design (CAD)models were generated simulating ten skulls. To simulate impact, 1.2J was applied on the orbital region of these models in four patterns. Pattern 1: All the energy works to cause the hydraulic effect. Pattern 2: Two-thirds of the energy works to cause the hydraulic effect; one-third of the energy works to cause the buckling effect. Pattern 3: One-third of the energy works to cause the hydraulic effect; two-thirds of the energy works to cause the buckling effect. Pattern 4: The entire energy quantum works to cause the buckling effect. Using the finite element method, the regions where fractures were theoretically expected to occur were calculated and were compared between the four patterns. More fracture damage occurred for Pattern 1 than Pattern 2, and for Pattern 3 than for Pattern 4. The hydraulic and buckling mechanisms interact with one another. When these two mechanisms are combined, the orbital walls tend to develop serious fractures. Copyright (c) 2009 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Scientific basis for safely shutting in the Macondo Well after the April 20, 2010 Deepwater Horizon blowout

USGS Publications Warehouse

Hickman, Stephen H.; Hsieh, Paul A.; Mooney, Walter D.; Enomoto, Catherine B.; Nelson, Philip H.; Flemings, Peter; Mayer, Larry; Moran, Kathryn; Weber, Thomas; McNutt, Marcia K.; Rice, James R.

2012-01-01

As part of the government response to the Deepwater Horizon blowout, a Well Integrity Team evaluated the geologic hazards of shutting in the Macondo Well at the seafloor and determined the conditions under which it could safely be undertaken. Of particular concern was the possibility that, under the anticipated high shut-in pressures, oil could leak out of the well casing below the seafloor. Such a leak could lead to new geologic pathways for hydrocarbon release to the Gulf of Mexico. Evaluating this hazard required analyses of 2D and 3D seismic surveys, seafloor bathymetry, sediment properties, geophysical well logs, and drilling data to assess the geological, hydrological, and geomechanical conditions around the Macondo Well. After the well was successfully capped and shut in on July 15, 2010, a variety of monitoring activities were used to assess subsurface well integrity. These activities included acquisition of wellhead pressure data, marine multichannel seismic profiles, seafloor and water-column sonar surveys, and wellhead visual/acoustic monitoring. These data showed that the Macondo Well was not leaking after shut in, and therefore, it could remain safely shut until reservoir pressures were suppressed (killed) with heavy drilling mud and the well was sealed with cement.

Trace element distributions in the water column near the Deepwater Horizon well blowout.

PubMed

Joung, DongJoo; Shiller, Alan M

2013-03-05

To understand the impact of the Deepwater Horizon well blowout on dissolved trace element concentrations, samples were collected from areas around the oil rig explosion site during four cruises in early and late May 2010, October 2010, and October 2011. In surface waters, Ba, Fe, Cu, Ni, Mn, and Co were relatively well correlated with salinity during all cruises, suggesting mixing with river water was the main influence on metal distributions in these waters. However, in deep oil/gas plumes (1000-1400 m depth), modestly elevated concentrations of Co and Ba were observed in late May, compared with postblowout conditions. Analysis of the oil itself along with leaching experiments confirm the oil as the source of the Co, whereas increased Ba was likely due to drilling mud used in the top kill attempt. Deep plume dissolved Mn largely reflected natural benthic input, though some samples showed slight elevation probably associated with the top kill. Dissolved Fe concentrations were low and also appeared largely topographically controlled and reflective of benthic input. Estimates suggest that microbial Fe demand may have affected the Fe distribution but probably not to the extent of Fe becoming a growth-limiting factor. Experiments showed that the dispersant can have some limited impact on dissolved-particulate metal partitioning.

Effects of oil from the 2010 Macondo well blowout on marsh foraminifera of Mississippi and Louisiana, USA.

PubMed

Brunner, Charlotte A; Yeager, Kevin M; Hatch, Rachel; Simpson, Sondra; Keim, Joseph; Briggs, Kevin B; Louchouarn, Patrick

2013-08-20

Foraminifera responded to both heavy and light oiling of marshes relative to unoiled control sites by changes to both standing stock and depth of habitation (DOH) in sediment following the 2010 Macondo well blowout. Push cores were taken from the middle marsh at sites classified as unoiled, lightly oiled, and heavily oiled based on concentrations of total polycyclic aromatic hydrocarbons ([TPAH]). Cores were sliced and stained with rose Bengal to detect live specimens of foraminifera. Short-term, sediment-mixing depths were determined using the penetration depths of excess (234)Th, and sedimentary organic carbon and carbonate were measured to distinguish depositional environments. Marsh foraminifera reacted to the highest oil concentration (5,000-18,000 ng/g of TPAH) by reducing standing stock and shortening the DOH compared with the control sites. At a second, less heavily oiled site, foraminifera responded with a shallower DOH, but with a boom in standing stock. Deformed, dead foraminifera occurred in all heavily oiled cores-but not elsewhere. Live foraminifera responded with a population boom at lightly oiled sites with [TPAH] near 1,100 ng/g. Changes in standing stock and DOH with [TPAH] suggest disturbance to the marsh food web, apparently due to oil pollution, and support the use of foraminifera as sentinel species.

ON THE MAGNETIC AND ENERGY CHARACTERISTICS OF RECURRENT HOMOLOGOUS JETS FROM AN EMERGING FLUX

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

Liu, Jiajia; Wang, Yuming; Liu, Rui

In this paper, we present the detailed analysis of recurrent homologous jets originating from an emerging negative magnetic flux at the edge of an active region. The observed jets show multithermal features. Their evolution shows high consistence with the characteristic parameters of the emerging flux, suggesting that with more free magnetic energy, the eruptions tend to be more violent, frequent, and blowout-like. The average temperature, average electron number density, and axial speed are found to be similar for different jets, indicating that they should have been formed by plasmas from similar origins. Statistical analysis of the jets and their footpointmore » region conditions reveals a strong positive relationship between the footpoint region total 131 Å intensity enhancement and jets’ length/width. Stronger linearly positive relationships also exist between the total intensity enhancement/thermal energy of the footpoint regions and jets’ mass/kinetic/thermal energy, with higher cross-correlation coefficients. All the above results together confirm the direct relationship between the magnetic reconnection and the jets and validate the important role of magnetic reconnection in transporting large amounts of free magnetic energy into jets. It is also suggested that there should be more free energy released during the magnetic reconnection of blowout than of standard jet events.« less

Lean Blow-out Studies in a Swirl Stabilized Annular Gas Turbine Combustor

NASA Astrophysics Data System (ADS)

Mishra, R. K.; Kishore Kumar, S.; Chandel, Sunil

2015-05-01

Lean blow out characteristics in a swirl stabilized aero gas turbine combustor have been studied using computational fluid dynamics. For CFD analysis, a 22.5° sector of an annular combustor is modeled using unstructured tetrahedral meshes comprising 1.2 × 106 elements. The governing equations are solved using the eddy dissipation combustion model in CFX. The primary combustion zone is analyzed by considering it as a well stirred reactor. The analysis has been carried out for different operating conditions of the reactants entering into the control volume. The results are treated as the base-line or reference values. Combustion lean blow-out limits are further characterized studying the behavior of combustion zone during transient engine operation. The validity of the computational study has been established by experimental study on a full-scale annular combustor in an air flow test facility that is capable of simulating different conditions at combustor inlet. The experimental result is in a good agreement with the analytical predictions. Upon increasing the combustor mass flow, the lean blow out limit increases, i.e., the blow out occurs at higher fuel-air ratios. In addition, when the operating pressure decreases, the lean blow out limit increases, i.e., blow out occurs at higher fuel-air ratios.

New design of a PEFC cathode separator of for water management

NASA Astrophysics Data System (ADS)

Sugiura, K.; Takahashi, N.; Kamimura, T.

2017-11-01

Generally, polymer electrolyte fuel cells (PEFCs) need humidifiers to prevent the drying of the membrane, but this use of humidifiers creates water management issues, such as the flooding/plugging phenomena and decreased system efficiency because of an increase in the electric energy needed for auxiliary equipment. Although most researchers have developed high-temperature membranes that do not need humidifiers, a lot of time is necessary for the development of these membranes, and these membranes drive up costs. Therefore, we propose a new cathode separator design that can recycle water generated by power generation in the same cell and a stack structure that can redistribute water collected in the cathode outlet manifold to drying cells. Because the new cathode separator has a bypass channel from the gas outlet to the gas inlet to transport excess water, a dry part in the gas inlet is supplied with excess water in the gas outlet through the bypass channel even if the PEFC is operated under dry conditions. Excess water in the PEFC stack can be transported from the cell with excess water to the drying cell through the cathode outlet manifold with a porous wall. Therefore, we confirm the influence of the plugging phenomenon in the cathode gas outlet manifold on the cell performance of each cell in the stack. As a result, the cell performance of the new cathode separator design is better than that of the standard separator under the low humidity conditions. We confirm that the plugging phenomenon in the cathode outlet manifold affects the cell performance of each cell in the stack.

Photonic devices on planar and curved substrates and methods for fabrication thereof

DOEpatents

Bartl, Michael H.; Barhoum, Moussa; Riassetto, David

2016-08-02

A versatile and rapid sol-gel technique for the fabrication of high quality one-dimensional photonic bandgap materials. For example, silica/titania multi-layer materials may be fabricated by a sol-gel chemistry route combined with dip-coating onto planar or curved substrate. A shock-cooling step immediately following the thin film heat-treatment process is introduced. This step was found important in the prevention of film crack formation--especially in silica/titania alternating stack materials with a high number of layers. The versatility of this sol-gel method is demonstrated by the fabrication of various Bragg stack-type materials with fine-tuned optical properties by tailoring the number and sequence of alternating layers, the film thickness and the effective refractive index of the deposited thin films. Measured optical properties show good agreement with theoretical simulations confirming the high quality of these sol-gel fabricated optical materials.

Fuel cell electrode interconnect contact material encapsulation and method

DOEpatents

Derose, Anthony J.; Haltiner, Jr., Karl J.; Gudyka, Russell A.; Bonadies, Joseph V.; Silvis, Thomas W.

2016-05-31

A fuel cell stack includes a plurality of fuel cell cassettes each including a fuel cell with an anode and a cathode. Each fuel cell cassette also includes an electrode interconnect adjacent to the anode or the cathode for providing electrical communication between an adjacent fuel cell cassette and the anode or the cathode. The interconnect includes a plurality of electrode interconnect protrusions defining a flow passage along the anode or the cathode for communicating oxidant or fuel to the anode or the cathode. An electrically conductive material is disposed between at least one of the electrode interconnect protrusions and the anode or the cathode in order to provide a stable electrical contact between the electrode interconnect and the anode or cathode. An encapsulating arrangement segregates the electrically conductive material from the flow passage thereby, preventing volatilization of the electrically conductive material in use of the fuel cell stack.

Cheating prevention in visual cryptography.

PubMed

Hu, Chih-Ming; Tzeng, Wen-Guey

2007-01-01

Visual cryptography (VC) is a method of encrypting a secret image into shares such that stacking a sufficient number of shares reveals the secret image. Shares are usually presented in transparencies. Each participant holds a transparency. Most of the previous research work on VC focuses on improving two parameters: pixel expansion and contrast. In this paper, we studied the cheating problem in VC and extended VC. We considered the attacks of malicious adversaries who may deviate from the scheme in any way. We presented three cheating methods and applied them on attacking existent VC or extended VC schemes. We improved one cheat-preventing scheme. We proposed a generic method that converts a VCS to another VCS that has the property of cheating prevention. The overhead of the conversion is near optimal in both contrast degression and pixel expansion.

Adjustable-Torque Truss-Joint Mechanism

NASA Technical Reports Server (NTRS)

Bush, Harold G.; Wallsom, Richard E.

1993-01-01

Threaded pin tightened or loosened; tedious trial-and-error procedure shortened. Mechanism joining strut and node in truss structure preloaded to desired stress to ensure tight, compressive fit preventing motion of strut during loading or vibration. Preload stress on stack of Belleville spring washers adjusted by tightening or loosening threaded Belleville-washer-alignment pin. Pin turned, by use of allen wrench, to adjust compression preload on Belleville washers and adjusts joint-operating torque.

Explosive parcel containment and blast mitigation container

DOEpatents

Sparks, Michael H.

2001-06-12

The present invention relates to a containment structure for containing and mitigating explosions. The containment structure is installed in the wall of the building and has interior and exterior doors for placing suspicious packages into the containment structure and retrieving them from the exterior of the building. The containment structure has a blast deflection chute and a blowout panel to direct over pressure from explosions away from the building, surrounding structures and people.

Air pollution from aircraft

NASA Technical Reports Server (NTRS)

Heywood, J. B.; Fay, J. A.; Chigier, N. A.

1979-01-01

A series of fundamental problems related to jet engine air pollution and combustion were examined. These include soot formation and oxidation, nitric oxide and carbon monoxide emissions mechanisms, pollutant dispension, flow and combustion characteristics of the NASA swirl can combustor, fuel atomization and fuel-air mixing processes, fuel spray drop velocity and size measurement, ignition and blowout. A summary of this work, and a bibliography of 41 theses and publications which describe this work, with abstracts, is included.

Oil Palm Phenolics Inhibit the In Vitro Aggregation of β-Amyloid Peptide into Oligomeric Complexes

PubMed Central

Koledova, Vera V.; Shin, Hyeari; Park, Jennifer H.; Tan, Yew Ai; Sambanthamurthi, Ravigadevi

2018-01-01

Alzheimer's disease is a severe neurodegenerative disease characterized by the aggregation of amyloid-β peptide (Aβ) into toxic oligomers which activate microglia and astrocytes causing acute neuroinflammation. Multiple studies show that the soluble oligomers of Aβ42 are neurotoxic and proinflammatory, whereas the monomers and insoluble fibrils are relatively nontoxic. We show that Aβ42 aggregation is inhibited in vitro by oil palm phenolics (OPP), an aqueous extract from the oil palm tree (Elaeis guineensis). The data shows that OPP inhibits stacking of β-pleated sheets, which is essential for oligomerization. We demonstrate the inhibition of Aβ42 aggregation by (1) mass spectrometry; (2) Congo Red dye binding; (3) 2D-IR spectroscopy; (4) dynamic light scattering; (5) transmission electron microscopy; and (6) transgenic yeast rescue assay. In the yeast rescue assay, OPP significantly reduces the cytotoxicity of aggregating neuropeptides in yeast genetically engineered to overexpress these peptides. The data shows that OPP inhibits (1) the aggregation of Aβ into oligomers; (2) stacking of β-pleated sheets; and (3) fibrillar growth and coalescence. These inhibitory effects prevent the formation of neurotoxic oligomers and hold potential as a means to reduce neuroinflammation and neuronal death and thereby may play some role in the prevention or treatment of Alzheimer's disease. PMID:29666700

Design and Implementation of an Operations Module for the ARGOS paperless Ship System

DTIC Science & Technology

1989-06-01

A. OPERATIONS STACK SCRIPTS SCRIPTS FOR STACK: operations * BACKGROUND #1: Operations * on openStack hide message box show menuBar pass openStack end... openStack ** CARD #1, BUTTON #1: Up ***** on mouseUp visual effect zoom out go to card id 10931 of stack argos end mouseUp ** CARD #1, BUTTON #2...STACK SCRIPTS SCRIPTS FOR STACK: Reports ** BACKGROUND #1: Operations * on openStack hie message box show menuBar pass openStack end openStack ** CARD #1

A review of polymer electrolyte membrane fuel cell durability test protocols

NASA Astrophysics Data System (ADS)

Yuan, Xiao-Zi; Li, Hui; Zhang, Shengsheng; Martin, Jonathan; Wang, Haijiang

Durability is one of the major barriers to polymer electrolyte membrane fuel cells (PEMFCs) being accepted as a commercially viable product. It is therefore important to understand their degradation phenomena and analyze degradation mechanisms from the component level to the cell and stack level so that novel component materials can be developed and novel designs for cells/stacks can be achieved to mitigate insufficient fuel cell durability. It is generally impractical and costly to operate a fuel cell under its normal conditions for several thousand hours, so accelerated test methods are preferred to facilitate rapid learning about key durability issues. Based on the US Department of Energy (DOE) and US Fuel Cell Council (USFCC) accelerated test protocols, as well as degradation tests performed by researchers and published in the literature, we review degradation test protocols at both component and cell/stack levels (driving cycles), aiming to gather the available information on accelerated test methods and degradation test protocols for PEMFCs, and thereby provide practitioners with a useful toolbox to study durability issues. These protocols help prevent the prolonged test periods and high costs associated with real lifetime tests, assess the performance and durability of PEMFC components, and ensure that the generated data can be compared.

Randomly Detected Genetically Modified (GM) Maize (Zea mays L.) near a Transport Route Revealed a Fragile 45S rDNA Phenotype

PubMed Central

Waminal, Nomar Espinosa; Ryu, Ki Hyun; Choi, Sun-Hee; Kim, Hyun Hee

2013-01-01

Monitoring of genetically modified (GM) crops has been emphasized to prevent their potential effects on the environment and human health. Monitoring of the inadvertent dispersal of transgenic maize in several fields and transport routes in Korea was carried out by qualitative multiplex PCR, and molecular analyses were conducted to identify the events of the collected GM maize. Cytogenetic investigations through fluorescence in situ hybridization (FISH) of the GM maize were performed to check for possible changes in the 45S rDNA cluster because this cluster was reported to be sensitive to replication and transcription stress. Three GM maize kernels were collected from a transport route near Incheon port, Korea, and each was found to contain NK603, stacked MON863 x NK603, and stacked NK603 x MON810 inserts, respectively. Cytogenetic analysis of the GM maize containing the stacked NK603 x MON810 insert revealed two normal compact 5S rDNA signals, but the 45S rDNA showed a fragile phenotype, demonstrating a “beads-on-a-string” fragmentation pattern, which seems to be a consequence of genetic modification. Implications of the 45S rDNA cluster fragility in GM maize are also discussed. PMID:24040165

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

Matthews, B.; Matthews, R.T.

Since Drake`s first oil well in 1859, well fires have been frequent and disastrous. Hardly a year has passed in over a century without a well fire somewhere in the world. In the 1920`s the classic method of fire fighting using explosives to starve the fire of oxygen was developed and it has been used extensively ever since. While explosives are still one of the most frequently used methods today, several other methods are used to supplement it where special conditions exist. Tunneling at an angle from a safe distance is used in some cases, especially where the fire ismore » too hot for a close approach on the ground surface. Pumping drilling muds into a well to plug it is another method that has been used successfully for some time. Diverter wells are occasionally used, and sometimes simply pumping enough water on a well fire is sufficient to extinguish it. Of course, prevention is always the best solution. Many advances in blow-out prevention devices have been developed in the last 50 years and the number of fires has been substantially reduced compared to the number of wells drilled. However, very little in new technology has been applied to oil well fire fighting in the 1960s, 1970s, or 1980s. Overall technological progress has accelerated tremendously in this period, of course, but new materials and equipment were not applied to this field for some reason. Saddam Hussein`s environmental holocaust in Kuwait changed that by causing many people throughout the world to focus their creative energy on more efficient oil well fire fighting methods.« less

The impact of stack geometry and mean pressure on cold end temperature of stack in thermoacoustic refrigeration systems

NASA Astrophysics Data System (ADS)

Wantha, Channarong

2018-02-01

This paper reports on the experimental and simulation studies of the influence of stack geometries and different mean pressures on the cold end temperature of the stack in the thermoacoustic refrigeration system. The stack geometry was tested, including spiral stack, circular pore stack and pin array stack. The results of this study show that the mean pressure of the gas in the system has a significant impact on the cold end temperature of the stack. The mean pressure of the gas in the system corresponds to thermal penetration depth, which results in a better cold end temperature of the stack. The results also show that the cold end temperature of the pin array stack decreases more than that of the spiral stack and circular pore stack geometry by approximately 63% and 70%, respectively. In addition, the thermal area and viscous area of the stack are analyzed to explain the results of such temperatures of thermoacoustic stacks.

Enceladus' near-surface CO2 gas pockets and surface frost deposits

NASA Astrophysics Data System (ADS)

Matson, Dennis L.; Davies, Ashley Gerard; Johnson, Torrence V.; Combe, Jean-Philippe; McCord, Thomas B.; Radebaugh, Jani; Singh, Sandeep

2018-03-01

Solid CO2 surface deposits were reported in Enceladus' South Polar Region by Brown et al. (2006). They noted that such volatile deposits are temporary and posited ongoing replenishment. We present a model for this replenishment by expanding on the Matson et al. (2012) model of subsurface heat and chemical transport in Enceladus. Our model explains the distributions of both CO2 frost and complexed CO2 clathrate hydrate as seen in the Cassini Visual and Infrared Mapping Spectrometer (VIMS) data. We trace the journey of CO2 from a subsurface ocean. The ocean-water circulation model of Matson et al. (2012) brings water up to near the surface where gas exsolves to form bubbles. Some of the CO2 bubbles are trapped and form pockets of gas in recesses at the bottom of the uppermost ice layer. When fissures break open these pockets, the CO2 gas is vented. Gas pocket venting is episodic compared to the more or less continuous eruptive plumes, emanating from the "tiger stripes", that are supported by plume chambers. Two styles of gas pocket venting are considered: (1) seeps, and (2) blowouts. The presence of CO2 frost patches suggests that the pocket gas slowly seeped through fractured, cold ice and when some of the gas reached the surface it was cold enough to condense (i.e., T ∼70 to ∼119 K). If the fissure opening is large, a blowout occurs. The rapid escape of gas and drop in pocket pressure causes water in the pocket to boil and create many small aerosol droplets of seawater. These may be carried along by the erupting gas. Electrically charged droplets can couple to the magnetosphere, and be dragged away from Enceladus. Most of the CO2 blowout gas escapes from Enceladus and the remainder is distributed globally. However, CO2 trapped in a clathrate structure does not escape. It is much heavier and slower moving than the CO2 gas. Its motion is ballistic and has an average range of about 17 km. Thus, it contributes to deposits in the vicinity of the vent. Local heat flow indicates that gas pockets can be located as deep as several tens of meters below the surface. Gas pockets can be reused, and we explore their life cycle.

Flame Propagation and Blowout in Hydrocarbon Jets: Experiments to Understand the Stability and Structure

DTIC Science & Technology

2012-07-29

Wilson and Kevin M. Lyons. On Diluted-Fuel Combustion Issues in Burning Biogas Surrogates, ASME-JERT, (12 2009): . doi: 2010/01/07 10:47:38 2 TOTAL...four coflow velocities are used, resulting in eight additional flow configurations. Table 2 contains the data obtained for these configurations, as...counterflow have higher stability limits than those in an oblique configuration. 4.) Conclusions Based on the results obtained from this experiment, a

Transient and steady-state performance of a single turbojet combustor with four different fuel nozzles

NASA Technical Reports Server (NTRS)

Mccafferty, Richard J; Donlon, Richard H

1955-01-01

Acceleration and steady-state performance of a tubular combustor was evaluated at two simulated altitudes with four different fuel nozzles. Temperature response lag was observed with all the nozzles. Except for rich-limit blowout, the only combustion failures observed during acceleration were with a fuel nozzle that gave an interrupted flow delivery during the acceleration. This same nozzle, because of superior fuel atomization, gave the highest steady-state combustion efficiencies.

Holocene geoarchaeology of the Sixteen Mile Beach barrier dunes in the Western Cape, South Africa

NASA Astrophysics Data System (ADS)

Compton, John S.; Franceschini, Giuliana

2005-01-01

Holocene evolution and human occupation of the Sixteen Mile Beach barrier dunes on the southwest coast of South Africa between Yzerfontein and Saldanha Bay are inferred from the radiocarbon ages of calcareous dune sand, limpet shell ( Patella spp.) manuports and gull-dropped white mussel shells ( Donax serra). A series of coast-parallel dunes have prograded seaward in response to an overall marine regression since the mid-Holocene with dated shell from relict foredunes indicating periods of shoreline progradation that correspond to drops in sea level at around 5900, 4500 and 2400 calibrated years before the present (cal yr B.P.). However, the active foredune, extensively covered by a layer of gull-dropped shell, has migrated 500 m inland by the recycling of eroded dune sand in response to an approximate 1 m sea level rise over the last 700 yr. Manuported limpet shells from relict blowouts on landward vegetated dunes indicate human occupation of coastal dune sites at 6200 and 6000 cal yr B.P. and help to fill the mid-Holocene gap in the regional archaeological record. Coastal midden shells associated with small hearth sites exposed in blowouts on the active foredune are contemporaneous (1600-500 cal yr B.P.) with large midden sites on the western margin of Langebaan Lagoon and suggest an increase in marine resource utilisation associated with the arrival of pastoralism in the Western Cape.

OBSERVATIONS OF A SERIES OF FLARES AND ASSOCIATED JET-LIKE ERUPTIONS DRIVEN BY THE EMERGENCE OF TWISTED MAGNETIC FIELDS

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

Lim, Eun-Kyung; Yurchyshyn, Vasyl; Kim, Sujin

We studied temporal changes of morphological and magnetic properties of a succession of four confined flares followed by an eruptive flare using the high-resolution New Solar Telescope (NST) operating at the Big Bear Solar Observatory (BBSO) and Helioseismic and Magnetic Imager (HMI) magnetograms and Atmospheric Image Assembly (AIA) EUV images provided by the Solar Dynamics Observatory (SDO). From the NST/Hα and the SDO/AIA 304 Å observations we found that each flare developed a jet structure that evolved in a manner similar to evolution of the blowout jet: (1) an inverted-Y-shaped jet appeared and drifted away from its initial position; (2) jets formed amore » curtain-like structure that consisted of many fine threads accompanied by subsequent brightenings near the footpoints of the fine threads; and finally, (3) the jet showed a twisted structure visible near the flare maximum. Analysis of the HMI data showed that both the negative magnetic flux and the magnetic helicity have been gradually increasing in the positive-polarity region, indicating the continuous injection of magnetic twist before and during the series of flares. Based on these results, we suggest that the continuous emergence of twisted magnetic flux played an important role in producing successive flares and developing a series of blowout jets.« less

Broad Low-Intensity Wings in the Emission-Line Profiles of Four Wolf-Rayet Galaxies

NASA Astrophysics Data System (ADS)

Méndez, David I.; Esteban, César

1997-10-01

High-resolution spectroscopic observations have been obtained for the Wolf-Rayet galaxies He 2-10, II Zw 40, POX 4, and Tol 35. Several subregions have been selected in each slit position in order to investigate possible spatial variations in the line profiles, radial velocities, and ionization conditions of the gas. The most remarkable feature of the spectra is the presence of asymmetric broad low-intensity wings in the profiles of the brightest emission lines. These spectral features are detected farther out from the star-forming knots, showing linear dimensions between 300 pc and 4.1 kpc. The maximum expansion velocity measured for this gas is between 120 and 340 km s-1 and appears to be quite constant along the slit for all the objects. Additional general properties of the spectra are (1) the quoted emission-line ratios are similar in the narrow and broad components, (2) no systematic differences of the behavior of the broad and narrow components have been found along the major and minor axis of the galaxies, and (3) the spatial distribution of the ionized gas is peaked centrally. Different mechanisms capable of producing the observed broad spectral features are discussed: cloud-cloud collisions in virialized gas, ``academic'' superbubbles, champagne flows, and superbubble blowout. It is concluded that superbubble blowout expanding over a cloudy medium can explain the observational properties in a reasonable manner.

Advanced Gas Turbine (AGT): Power-train system development

NASA Technical Reports Server (NTRS)

Helms, H. E.; Johnson, R. A.; Gibson, R. K.; Smith, L. B.

1983-01-01

Technical work on the design and effort leading to the testing of a 74.5 kW (100 hp) automotive gas turbine is described. The general effort was concentrated on building an engine for test starting in July. The buildup progressed with only routine problems and the engine was delivered to the test stand 9 July. In addition to the engine build effort, work continued in selected component areas. Ceramic turbine parts were built and tested. Burst tests of ceramic rotors show strengths are approaching that achieved in test bars; proof testing is required for acceptable strength ceramic vanes. Over 25 hours was accumulated on the combustor rig in three test modes: pilot nozzle only, start nozzle, and main nozzle operation. Satisfactory ignition was achieved for a wide range of starting speeds and the lean blowout limit was as low as 0.06 kg/b (0.14 lb/hr). Lean blowout was more a function of nozzle atomization than fuel/air ratio. A variety of cycle points were tested. Transition from start nozzle flow to main nozzle flow was done manually without difficulty. Regenerator parts were qualification tested without incident and the parts were assembled on schedule. Rig based performance matched first build requirements. Repeated failures in the harmonic drive gearbox during rig testing resulted in that concept being abandoned for an alternate scheme.

Anomalously High Recruitment of the 2010 Gulf Menhaden (Brevoortia patronus) Year Class: Evidence of Indirect Effects from the Deepwater Horizon Blowout in the Gulf of Mexico.

PubMed

Short, Jeffrey W; Geiger, Harold J; Haney, J Christopher; Voss, Christine M; Vozzo, Maria L; Guillory, Vincent; Peterson, Charles H

2017-07-01

Gulf menhaden (Brevoortia patronus) exhibited unprecedented juvenile recruitment in 2010 during the year of the Deepwater Horizon well blowout, exceeding the prior 39-year mean by more than four standard deviations near the Mississippi River. Abundance of that cohort remained exceptionally high for two subsequent years as recruits moved into older age classes. Such changes in this dominant forage fish population can be most parsimoniously explained as consequences of release from predation. Contact with crude oil induced high mortality of piscivorous seabirds, bottlenose dolphin (Tursiops truncatus), waders, and other fish-eating marsh birds, all of which are substantial consumers of Gulf menhaden. Diversions of fresh water from the Mississippi River to protect coastal marshes from oiling depressed salinities, impairing access to juvenile Gulf menhaden by aquatic predators that avoid low-salinity estuarine waters. These releases from predation led to an increase of Gulf menhaden biomass in 2011 to 2.4 million t, or more than twice the average biomass of 1.1 million t for the decade prior to 2010. Biomass increases of this magnitude in a major forage fish species suggest additional trophically linked effects at the population-, trophic-level and ecosystem scales, reflecting an heretofore little appreciated indirect effect that may be associated with major oil spills in highly productive marine waters.

Hydrocarbon composition and concentrations in the Gulf of Mexico sediments in the 3 years following the Macondo well blowout.

PubMed

Babcock-Adams, Lydia; Chanton, Jeffrey P; Joye, Samantha B; Medeiros, Patricia M

2017-10-01

In April of 2010, the Macondo well blowout in the northern Gulf of Mexico resulted in an unprecedented release of oil into the water column at a depth of approximately 1500 m. A time series of surface and subsurface sediment samples were collected to the northwest of the well from 2010 to 2013 for molecular biomarker and bulk carbon isotopic analyses. While no clear trend was observed in subsurface sediments, surface sediments (0-3 cm) showed a clear pattern with total concentrations of n-alkanes, unresolved complex mixture (UCM), and petroleum biomarkers (terpanes, hopanes, steranes) increasing from May to September 2010, peaking in late November 2010, and strongly decreasing in the subsequent years. The peak in hydrocarbon concentrations were corroborated by higher organic carbon contents, more depleted Δ 14 C values and biomarker ratios similar to those of the initial MC252 crude oil reported in the literature. These results indicate that at least part of oil discharged from the accident sedimented to the seafloor in subsequent months, resulting in an apparent accumulation of hydrocarbons on the seabed by the end of 2010. Sediment resuspension and transport or biodegradation may account for the decrease in sedimented oil quantities in the years following the Macondo well spill. Copyright © 2017 Elsevier Ltd. All rights reserved.

Blow-out protector and fire control system for petroleum exploration

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

Caraway, M.F.; Caraway, B.L.

1987-10-06

A blow-out protector is described for an oil well comprising a housing having a vertical passageway therethrough for a Kelly. The housing has a lower end adapter flange to be connected to a well casing, an elastomeric body having an opening for the Kelly and carried on the Kelly for providing sealing contact with the Kelly and housing passageway, a catch ring secured to the Kelly and having a surface defined by a given diameter, a compressor ring plate positioned below the elastomeric body on the Kelly, means on an interior of the housing having a given diameter and preventingmore » the compressor ring plate from falling down and yet providing engagement with the surface of the catch ring, the compressor ring plate having a hole for passage of the Kelly drive-mechanism for the drill pipe, the catch ring on the Kelly positioned below the compressor plate. The diameter of the catch ring is smaller than the diameter of the interior means on the housing so that when the Kelly is pulled up the catch ring will contact and force the compressor ring plate against the elastomeric body and force the elastomeric body into tight contact with both the Kelly and the housing thus sealing the space between the Kelly and the housing against a blow-out.« less

Simplified efficient phosphorescent organic light-emitting diodes by organic vapor phase deposition

NASA Astrophysics Data System (ADS)

Pfeiffer, P.; Beckmann, C.; Stümmler, D.; Sanders, S.; Simkus, G.; Heuken, M.; Vescan, A.; Kalisch, H.

2017-12-01

The most efficient phosphorescent organic light-emitting diodes (OLEDs) are comprised of complex stacks with numerous organic layers. State-of-the-art phosphorescent OLEDs make use of blocking layers to confine charge carriers and excitons. On the other hand, simplified OLEDs consisting of only three organic materials have shown unexpectedly high efficiency when first introduced. This was attributed to superior energy level matching and suppressed external quantum efficiency (EQE) roll-off. In this work, we study simplified OLED stacks, manufactured by organic vapor phase deposition, with a focus on charge balance, turn-on voltage (Von), and efficiency. To prevent electrons from leaking through the device, we implemented a compositionally graded emission layer. By grading the emitter with the hole transport material, charge confinement is enabled without additional blocking layers. Our best performing organic stack is composed of only three organic materials in two layers including the emitter Ir(ppy)3 and yields a Von of 2.5 V (>1 cd/m2) and an EQE of 13% at 3000 cd/m2 without the use of any additional light extraction techniques. Changes in the charge balance, due to barrier tuning or adjustments in the grading parameters and layer thicknesses, are clearly visible in the current density-voltage-luminance (J-V-L) measurements. As charge injection at the electrodes and organic interfaces is of great interest but difficult to investigate in complex device structures, we believe that our simplified organic stack is not only a potent alternative to complex state-of-the-art OLEDs but also a well suited test vehicle for experimental studies focusing on the modification of the electrode-organic semiconductor interface.

Method and device for electroextraction of heavy metals from technological solutions and wastewater

DOEpatents

Khalemsky, Aron Mikhailov; Payusov, Sergei Abramovic; Kelner, Leonid; Jo, Jae

2005-05-03

The basic principles of the method for heavy metals electroextraction from technological solutions and wastewater includes pretreating to remove Chromium-6 and high concentrations of heavy metals and periodically treating in a six-electrode bipolar cylindrical electroreactor made of non-conducting material to achieve lower accepted levels of impurities. Six cylindrical steel electrodes form two triode stacks and are fed with three-phase alternating current of commercial frequency (50-60 Hz), which can be pulsed. Each phase of the three-phase current is connected to three electrodes of one triode stack or in parallel to two triode stacks. The parallel connection of three-phase current to two triode stacks is performed so that the same phase of the three phase current is connected in parallel with each two opposite electrodes of six electrodes located along the periphery, or with two adjacent electrodes. A bipolar stationary aluminum electrode is situated in the inter-electrode space. In one of the embodiments, the bipolar electrode is made of a perforated heat-resistant plastic container filled with secondary aluminum and duralumin scrap. In another embodiment, the bipolar electrode of aluminum or duralumin scrap may be made without a perforated container and is placed in the inter-electrode space as a bulk scrap. In this case, to prevent shorts, each of six steel electrodes is placed in isolated perforated plastic shell with holes of 5 mm in diameter. Non-ferrous metals are extracted in a form of ferrite-chromites, and aluminates as well as hydroxyl salts deposited in the inter-electrode space without electrolysis deposits on electrodes. Deposits are separated from solution by known methods of filtration.

Natural and Unnatural Oil Layers on the Surface of the Gulf of Mexico Detected and Quantified in Synthetic Aperture RADAR Images with Texture Classifying Neural Network Algorithms

NASA Astrophysics Data System (ADS)

MacDonald, I. R.; Garcia-Pineda, O. G.; Morey, S. L.; Huffer, F.

2011-12-01

Effervescent hydrocarbons rise naturally from hydrocarbon seeps in the Gulf of Mexico and reach the ocean surface. This oil forms thin (~0.1 μm) layers that enhance specular reflectivity and have been widely used to quantify the abundance and distribution of natural seeps using synthetic aperture radar (SAR). An analogous process occurred at a vastly greater scale for oil and gas discharged from BP's Macondo well blowout. SAR data allow direct comparison of the areas of the ocean surface covered by oil from natural sources and the discharge. We used a texture classifying neural network algorithm to quantify the areas of naturally occurring oil-covered water in 176 SAR image collections from the Gulf of Mexico obtained between May 1997 and November 2007, prior to the blowout. Separately we also analyzed 36 SAR images collections obtained between 26 April and 30 July, 2010 while the discharged oil was visible in the Gulf of Mexico. For the naturally occurring oil, we removed pollution events and transient oceanographic effects by including only the reflectance anomalies that that recurred in the same locality over multiple images. We measured the area of oil layers in a grid of 10x10 km cells covering the entire Gulf of Mexico. Floating oil layers were observed in only a fraction of the total Gulf area amounting to 1.22x10^5 km^2. In a bootstrap sample of 2000 replications, the combined average area of these layers was 7.80x10^2 km^2 (sd 86.03). For a regional comparison, we divided the Gulf of Mexico into four quadrates along 90° W longitude, and 25° N latitude. The NE quadrate, where the BP discharge occurred, received on average 7.0% of the total natural seepage in the Gulf of Mexico (5.24 x10^2 km^2, sd 21.99); the NW quadrate received on average 68.0% of this total (5.30 x10^2 km^2, sd 69.67). The BP blowout occurred in the NE quadrate of the Gulf of Mexico; discharged oil that reached the surface drifted over a large area north of 25° N. Performing a similar estimate using 5x5 km grid cells, we observed discharged oil over an area of 1.20x10^5 km^2; 91% of this area was east of 90° W. The average area oil covered water observed in the SAR images was 4.41x104^ km^2, 98% of which was observed in the eastern Gulf. Numerical oil spill model experiments are used to clarify the distinction between the area impacted by the BP oil spill and the surface slicks due to known natural seeps. Natural oil seepage has been cited as a background source of hydrocarbon contamination in the Gulf of Mexico. Our direct comparison shows that during the blowout, the discharged oil impacted an average area two orders of magnitude greater than the entire Gulf total and three orders of magnitude greater than the usual dose received in the northeastern region. Because the layers of discharged oil were often many times thicker than natural seep oil, additional scale factors are required to show the true difference in doses. These differences should be weighed when evaluating the relative impact of natural and unnatural oil in a large marine ecosystem.

TESTING FOR CPT VIOLATION IN B^{0_{s SEMILEPTONIC DECAYS}}

NASA Astrophysics Data System (ADS)

Kooten, R. Van

2014-01-01

A DØ analysis measuring the charge asymmetry A^{b_{sl of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider has shown indications of possible anomalous CP violation in the mixing of neutral B mesons. This result has been used to extract the first senstivity to CPT violation in the B0s system. An analysis to explore further this anomaly by specifically measuring the semileptonic charge asymmetry, assl, in B0s decays is described, as well as how a variant of this analysis can be used to explore a larger set of CPT-violating parameters in the B0s system for the first time.}}

Fuel cell stack arrangements

DOEpatents

Kothmann, Richard E.; Somers, Edward V.

1982-01-01

Arrangements of stacks of fuel cells and ducts, for fuel cells operating with separate fuel, oxidant and coolant streams. An even number of stacks are arranged generally end-to-end in a loop. Ducts located at the juncture of consecutive stacks of the loop feed oxidant or fuel to or from the two consecutive stacks, each individual duct communicating with two stacks. A coolant fluid flows from outside the loop, into and through cooling channels of the stack, and is discharged into an enclosure duct formed within the loop by the stacks and seals at the junctures at the stacks.

AGC-4 Experiment Irradiation Monitoring Data Qualification Interim Report

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

Hull, Laurence Charles

2016-08-01

The Graphite Technology Development Program is running a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The fourth experiment, Advanced Graphite Creep 4 (AGC 4), began with Advanced Test Reactor (ATR) cycle 157D on May 30, 2015, and has been irradiated for two cycles. The capsule was removed from the reactor after ATR cycle 158A, which ended on January 2, 2016, due to interference with another experiment. Irradiation will resume when the interfering experiment is removed from the reactor. This report documents qualification of AGC 4 experiment irradiation monitoring data for use by themore » Advanced Reactor Technologies (ART) Technology Development Office (TDO) Program for research and development activities required to design and license the first HTR nuclear plant. Qualified data meet the requirements for use as described in the experiment planning and quality assurance documents. Failed data do not meet the requirements and provide no useable information. Trend data may not meet all requirements, but still provide some useable information. Use of Trend data requires assessment of how any deficiencies affect a particular use of the data. All thermocouples (TCs) have functioned throughout the AGC-4 experiment. All temperature data are Qualified for use by the ART TDO Program. Argon, helium, and total gas flow data were within expected ranges and are Qualified for use by the ART TDO Program. Discharge gas line moisture values were consistently low during cycle 157D. At the start of cycle 158A, gas moisture briefly spiked to over 600 ppmv and then declined throughout the cycle. Moisture values are within the measurement range of the instrument and are Qualified for use by the ART TDO Program. Graphite creep specimens were subjected to one of three loads, 393, 491, or 589 lbf. For a brief period during cycle 157D between 12:19 on June 2, 2015 and 08:23 on June 11, 2015 the load cells were wired incorrectly resulting in missing stack load data. Missing stack loads were estimated from measured ram pressures using regression equations developed from the existing data from cycle 157D. Estimated stack loads during this period are considered to be an accurate representation of actual load applied to the stacks. These loads deviate slightly from the planned loads. This deviation does not prevent the data from being Qualified for use, but must be taken into account when analyzing the effect of load on creep. Stack displacement increased consistently throughout the first two cycles with total displacement ranging from 0.4 to 0.8 in. During ATR outages, a set of pneumatic rams raised the stacks of graphite creep specimens to ensure the specimens were not stuck within the test train. This stack raising was performed twice. All stacks were raised successfully each time. The load and displacement data are Qualified for use by the ART TDO Program.« less

Some Operating Experience and Problems Encountered During Operation of a Free-jet Facility

NASA Technical Reports Server (NTRS)

Mcaulay, John E; Prince, William R

1957-01-01

During a free-jet investigation of a 28-inch ram-jet engine at a Mach number of 2.35, flow pulsation at the engine inlet were discovered which proved to have an effect on the engine performance and operational characteristics, particularly the engine rich blowout limits. This report discusses the finding of the flow pulsations, their elimination, and effect. Other facility characteristics, such as the establishment of flow simulation and the degree of subcritical operation of the diffuser, are also explained.

Advancements in dynamic kill calculations for blowout wells

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

Kouba, G.E.; MacDougall, G.R.; Schumacher, B.W.

1993-09-01

This paper addresses the development, interpretation, and use of dynamic kill equations. To this end, three simple calculation techniques are developed for determining the minimum dynamic kill rate. Two techniques contain only single-phase calculations and are independent of reservoir inflow performance. Despite these limitations, these two methods are useful for bracketing the minimum flow rates necessary to kill a blowing well. For the third technique, a simplified mechanistic multiphase-flow model is used to determine a most-probable minimum kill rate.

Accurate modeling of the hose instability in plasma wakefield accelerators

NASA Astrophysics Data System (ADS)

Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.; Martinez de la Ossa, A.; Osterhoff, J.; Esarey, E.; Leemans, W. P.

2018-05-01

Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. It paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

Improved 3D seismic attribute mapping by CRS stacking instead of NMO stacking: Application to a geothermal reservoir in the Polish Basin

NASA Astrophysics Data System (ADS)

Pussak, Marcin; Bauer, Klaus; Stiller, Manfred; Bujakowski, Wieslaw

2014-04-01

Within a seismic reflection processing work flow, the common-reflection-surface (CRS) stack can be applied as an alternative for the conventional normal moveout (NMO) or the dip moveout (DMO) stack. The advantages of the CRS stack include (1) data-driven automatic determination of stacking operator parameters, (2) imaging of arbitrarily curved geological boundaries, and (3) significant increase in signal-to-noise (S/N) ratio by stacking far more traces than used in a conventional stack. In this paper we applied both NMO and CRS stackings to process a sparse 3D seismic data set acquired within a geothermal exploration study in the Polish Basin. The stacked images show clear enhancements in quality achieved by the CRS stack in comparison with the conventional stack. While this was expected from previous studies, we also found remarkable improvements in the quality of seismic attributes when the CRS stack was applied instead of the conventional stack. For the major geothermal target reservoir (Lower Jurassic horizon Ja1), we present a comparison between both stacking methods for a number of common attributes, including root-mean-square (RMS) amplitudes, instantaneous frequencies, coherency, and spectral decomposition attributes derived from the continuous wavelet transform. The attribute maps appear noisy and highly fluctuating after the conventional stack, and are clearly structured after the CRS stack. A seismic facies analysis was finally carried out for the Ja1 horizon using the attributes derived from the CRS stack by using self-organizing map clustering techniques. A corridor parallel to a fault system was identified, which is characterized by decreased RMS amplitudes and decreased instantaneous frequencies. In our interpretation, this region represents a fractured, fluid-bearing compartment within the sandstone reservoir, which indicates favorable conditions for geothermal exploitation.

High Efficiency Stacked Organic Light-Emitting Diodes Employing Li2O as a Connecting Layer

NASA Astrophysics Data System (ADS)

Kanno, Hiroshi; Hamada, Yuji; Nishimura, Kazuki; Okumoto, Kenji; Saito, Nobuo; Ishida, Hiroki; Takahashi, Hisakazu; Shibata, Kenichi; Mameno, Kazunobu

2006-12-01

We demonstrate the high-efficiency stacked organic light-emitting diodes (OLEDs) introducing new connecting layers. In the green stacked OLEDs, the external efficiencies increase proportionally to the number of the stacked units without suffering the decrease in power efficiency. The current, power and external efficiencies at 0.5 mA/cm2 of the stacked OLED with six stacked units (6-stacked OLED) have reached 235 cd/A, 46.6 lm/W, and 65.8%, respectively. Furthermore, we have applied the connecting layers to a white stacked OLED and fabricated an active-matrix full-color display with a low temperature polysilicon thin film transistor backplane. In the device, the current efficiency of the white 2-stacked OLED is enhanced by a factor of 2.2. The initial luminance drop is significantly suppressed for the white 2-stacked OLED compared to 1-stacked OLED. The proposed white stacked OLED technology can be applied to a full-color display for a practical use.

Non-uniform muscle fat replacement along the proximodistal axis in Duchenne muscular dystrophy.

PubMed

Hooijmans, M T; Niks, E H; Burakiewicz, J; Anastasopoulos, C; van den Berg, S I; van Zwet, E; Webb, A G; Verschuuren, J J G M; Kan, H E

2017-05-01

The progressive replacement of muscle tissue by fat in Duchenne muscular dystrophy (DMD) has been studied using quantitative MRI between, but not within, individual muscles. We studied fat replacement along the proximodistal muscle axis using the Dixon technique on a 3T MR scanner in 22 DMD patients and 12 healthy controls. Mean fat fractions per muscle per slice for seven lower and upper leg muscles were compared between and within groups assuming a parabolic distribution. Average fat fraction for a small central slice stack and a large coverage slice stack were compared to the value when the stack was shifted one slice (15 mm) up or down. Higher fat fractions were observed in distal and proximal muscle segments compared to the muscle belly in all muscles of the DMD subjects (p <0.001). A shift of 15 mm resulted in a difference in mean fat fraction which was on average 1-2% ranging up to 12% (p <0.01). The muscle end regions are exposed to higher mechanical strain, which points towards mechanical disruption of the sarcolemma as one of the key factors in the pathophysiology. Overall, this non-uniformity in fat replacement needs to be taken into account to prevent sample bias when applying quantitative MRI as biomarker in clinical trials for DMD. Copyright © 2017 Elsevier B.V. All rights reserved.

Spectral multiplexing using stacked volume-phase holographic gratings - I

NASA Astrophysics Data System (ADS)

Zanutta, A.; Landoni, M.; Riva, M.; Bianco, A.

2017-08-01

Many focal-reducer spectrographs, currently available at state-of-the-art telescopes facilities, would benefit from a simple refurbishing that could increase both the resolution and spectral range in order to cope with the progressively challenging scientific requirements, but, in order to make this update appealing, it should minimize the changes in the existing structure of the instrument. In the past, many authors proposed solutions based on stacking subsequently layers of dispersive elements and recording multiple spectra in one shot (multiplexing). Although this idea is promising, it brings several drawbacks and complexities that prevent the straightforward integration of such a device in a spectrograph. Fortunately, nowadays, the situation has changed dramatically, thanks to the successful experience achieved through photopolymeric holographic films, used to fabricate common volume-phase holographic gratings (VPHGs). Thanks to the various advantages made available by these materials in this context, we propose an innovative solution to design a stacked multiplexed VPHG that is able to secure efficiently different spectra in a single shot. This allows us to increase resolution and spectral range enabling astronomers to greatly economize their awarded time at the telescope. In this paper, we demonstrate the applicability of our solution, both in terms of expected performance and feasibility, supposing the upgrade of the Gran Telescopio CANARIAS (GTC) Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy (OSIRIS).

Improvement of optical quality of semipolar (11 2 ¯ 2 ) GaN on m-plane sapphire by in-situ epitaxial lateral overgrowth

NASA Astrophysics Data System (ADS)

Monavarian, Morteza; Izyumskaya, Natalia; Müller, Marcus; Metzner, Sebastian; Veit, Peter; Can, Nuri; Das, Saikat; Özgür, Ümit; Bertram, Frank; Christen, Jürgen; Morkoç, Hadis; Avrutin, Vitaliy

2016-04-01

Among the major obstacles for development of non-polar and semipolar GaN structures on foreign substrates are stacking faults which deteriorate the structural and optical quality of the material. In this work, an in-situ SiNx nano-network has been employed to achieve high quality heteroepitaxial semipolar (11 2 ¯ 2 ) GaN on m-plane sapphire with reduced stacking fault density. This approach involves in-situ deposition of a porous SiNx interlayer on GaN that serves as a nano-mask for the subsequent growth, which starts in the nanometer-sized pores (window regions) and then progresses laterally as well, as in the case of conventional epitaxial lateral overgrowth (ELO). The inserted SiNx nano-mask effectively prevents the propagation of defects, such as dislocations and stacking faults, in the growth direction and thus reduces their density in the overgrown layers. The resulting semipolar (11 2 ¯ 2 ) GaN layers exhibit relatively smooth surface morphology and improved optical properties (PL intensity enhanced by a factor of 5 and carrier lifetimes by 35% to 85% compared to the reference semipolar (11 2 ¯ 2 ) GaN layer) which approach to those of the c-plane in-situ nano-ELO GaN reference and, therefore, holds promise for light emitting and detecting devices.

Braided and Stacked Electrospun Nanofibrous Scaffolds for Tendon and Ligament Tissue Engineering

PubMed Central

Rothrauff, Benjamin B.; Lauro, Brian B.; Yang, Guang; Debski, Richard E.; Musahl, Volker

2017-01-01

Tendon and ligament injuries are a persistent orthopedic challenge given their poor innate healing capacity. Nonwoven electrospun nanofibrous scaffolds composed of polyesters have been used to mimic the mechanics and topographical cues of native tendons and ligaments. However, nonwoven nanofibers have several limitations that prevent broader clinical application, including poor cell infiltration, as well as tensile and suture-retention strengths that are inferior to native tissues. In this study, multilayered scaffolds of aligned electrospun nanofibers of two designs–stacked or braided–were fabricated. Mechanical properties, including structural and mechanical properties and suture-retention strength, were determined using acellular scaffolds. Human bone marrow-derived mesenchymal stem cells (MSCs) were seeded on scaffolds for up to 28 days, and assays for tenogenic differentiation, histology, and biochemical composition were performed. Braided scaffolds exhibited improved tensile and suture-retention strengths, but reduced moduli. Both scaffold designs supported expression of tenogenic markers, although the effect was greater on braided scaffolds. Conversely, cell infiltration was superior in stacked constructs, resulting in enhanced cell number, total collagen content, and total sulfated glycosaminoglycan content. However, when normalized against cell number, both designs modulated extracellular matrix protein deposition to a similar degree. Taken together, this study demonstrates that multilayered scaffolds of aligned electrospun nanofibers supported tenogenic differentiation of seeded MSCs, but the macroarchitecture is an important consideration for applications of tendon and ligament tissue engineering. PMID:28071988

Braided and Stacked Electrospun Nanofibrous Scaffolds for Tendon and Ligament Tissue Engineering.

PubMed

Rothrauff, Benjamin B; Lauro, Brian B; Yang, Guang; Debski, Richard E; Musahl, Volker; Tuan, Rocky S

2017-05-01

Tendon and ligament injuries are a persistent orthopedic challenge given their poor innate healing capacity. Nonwoven electrospun nanofibrous scaffolds composed of polyesters have been used to mimic the mechanics and topographical cues of native tendons and ligaments. However, nonwoven nanofibers have several limitations that prevent broader clinical application, including poor cell infiltration, as well as tensile and suture-retention strengths that are inferior to native tissues. In this study, multilayered scaffolds of aligned electrospun nanofibers of two designs-stacked or braided-were fabricated. Mechanical properties, including structural and mechanical properties and suture-retention strength, were determined using acellular scaffolds. Human bone marrow-derived mesenchymal stem cells (MSCs) were seeded on scaffolds for up to 28 days, and assays for tenogenic differentiation, histology, and biochemical composition were performed. Braided scaffolds exhibited improved tensile and suture-retention strengths, but reduced moduli. Both scaffold designs supported expression of tenogenic markers, although the effect was greater on braided scaffolds. Conversely, cell infiltration was superior in stacked constructs, resulting in enhanced cell number, total collagen content, and total sulfated glycosaminoglycan content. However, when normalized against cell number, both designs modulated extracellular matrix protein deposition to a similar degree. Taken together, this study demonstrates that multilayered scaffolds of aligned electrospun nanofibers supported tenogenic differentiation of seeded MSCs, but the macroarchitecture is an important consideration for applications of tendon and ligament tissue engineering.

Guanine base stacking in G-quadruplex nucleic acids

PubMed Central

Lech, Christopher Jacques; Heddi, Brahim; Phan, Anh Tuân

2013-01-01

G-quadruplexes constitute a class of nucleic acid structures defined by stacked guanine tetrads (or G-tetrads) with guanine bases from neighboring tetrads stacking with one another within the G-tetrad core. Individual G-quadruplexes can also stack with one another at their G-tetrad interface leading to higher-order structures as observed in telomeric repeat-containing DNA and RNA. In this study, we investigate how guanine base stacking influences the stability of G-quadruplexes and their stacked higher-order structures. A structural survey of the Protein Data Bank is conducted to characterize experimentally observed guanine base stacking geometries within the core of G-quadruplexes and at the interface between stacked G-quadruplex structures. We couple this survey with a systematic computational examination of stacked G-tetrad energy landscapes using quantum mechanical computations. Energy calculations of stacked G-tetrads reveal large energy differences of up to 12 kcal/mol between experimentally observed geometries at the interface of stacked G-quadruplexes. Energy landscapes are also computed using an AMBER molecular mechanics description of stacking energy and are shown to agree quite well with quantum mechanical calculated landscapes. Molecular dynamics simulations provide a structural explanation for the experimentally observed preference of parallel G-quadruplexes to stack in a 5′–5′ manner based on different accessible tetrad stacking modes at the stacking interfaces of 5′–5′ and 3′–3′ stacked G-quadruplexes. PMID:23268444

The Direct FuelCell™ stack engineering

NASA Astrophysics Data System (ADS)

Doyon, J.; Farooque, M.; Maru, H.

FuelCell Energy (FCE) has developed power plants in the size range of 300 kW to 3 MW for distributed power generation. Field-testing of the sub-megawatt plants is underway. The FCE power plants are based on its Direct FuelCell™ (DFC) technology. This is so named because of its ability to generate electricity directly from a hydrocarbon fuel, such as natural gas, by reforming it inside the fuel cell stack itself. All FCE products use identical 8000 cm 2 cell design, approximately 350-400 cells per stack, external gas manifolds, and similar stack compression systems. The difference lies in the packaging of the stacks inside the stack module. The sub-megawatt system stack module contains a single horizontal stack whereas the MW-class stack module houses four identical vertical stacks. The commonality of the design, internal reforming features, and atmospheric operation simplify the system design, reduce cost, improve efficiency, increase reliability and maintainability. The product building-block stack design has been advanced through three full-size stack operations at company's headquarters in Danbury, CT. The initial proof-of-concept of the full-size stack design was verified in 1999, followed by a 1.5 year of endurance verification in 2000-2001, and currently a value-engineered stack version is in operation. This paper discusses the design features, important engineering solutions implemented, and test results of FCE's full-size DFC stacks.

Ultrasonic/Sonic Impacting Penetrators

NASA Technical Reports Server (NTRS)

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

2008-01-01

Ultrasonic/sonic impacting penetrators (USIPs) are recent additions to the series of apparatuses based on ultrasonic/sonic drill corers (USDCs). A USIP enables a rod probe to penetrate packed soil or another substance of similar consistency, without need to apply a large axial force that could result in buckling of the probe or in damage to some buried objects. USIPs were conceived for use in probing and analyzing soil to depths of tens of centimeters in the vicinity of buried barrels containing toxic waste, without causing rupture of the barrels. USIPs could also be used for other purposes, including, for example, searching for pipes, barrels, or other hard objects buried in soil; and detecting land mines. USDCs and other apparatuses based on USDCs have been described in numerous previous NASA Tech Briefs articles. The ones reported previously were designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. To recapitulate: A USDC can be characterized as a lightweight, low-power, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. As shown in the figure, a basic USDC includes a piezoelectric stack, a backing and a horn connected to the stack, a free mass (free in the sense that it can slide axially a short distance between the horn and the shoulder of tool bit), and a tool bit, i.e., probe for USIP. The piezoelectric stack is driven at the resonance frequency of the stack/horn/backing assembly to create ultrasonic vibrations that are mechanically amplified by the horn. To prevent fracture during operation, the piezoelectric stack is held in compression by a bolt. The bouncing of the free mass between the horn and the tool bit at sonic frequencies generates hammering actions to the bit that are more effective for drilling than is the microhammering action of ultrasonic vibrations in ordinary ultrasonic drills. The hammering actions are so effective that the axial force needed to make the tool bit advance into the material of interest is much smaller than in ordinary twist drilling, ultrasonic drilling, or ordinary steady pushing.

Improved photoswitching response times of MoS2 field-effect transistors by stacking p-type copper phthalocyanine layer

NASA Astrophysics Data System (ADS)

Pak, Jinsu; Min, Misook; Cho, Kyungjune; Lien, Der-Hsien; Ahn, Geun Ho; Jang, Jingon; Yoo, Daekyoung; Chung, Seungjun; Javey, Ali; Lee, Takhee

2016-10-01

Photoswitching response times (rise and decay times) of a vertical organic and inorganic heterostructure with p-type copper phthalocyanine (CuPc) and n-type molybdenum disulfide (MoS2) semiconductors are investigated. By stacking a CuPc layer on MoS2 field effect transistors, better photodetection capability and fast photoswitching rise and decay phenomena are observed. Specifically, with a 2 nm-thick CuPc layer on the MoS2 channel, the photoswitching decay time decreases from 3.57 s to 0.18 s. The p-type CuPc layer, as a passivation layer, prevents the absorption of oxygen on the surface of the MoS2 channel layer, which results in a shortened photoswitching decay time because adsorbed oxygen destroys the balanced ratio of electrons and holes, leading to the interruption of recombination processes. The suggested heterostructure may deliver enhanced photodetection abilities and photoswitching characteristics for realizing ultra-thin and sensitive photodetectors.

Layout designs of surface barrier coatings for boosting the capability of oxygen/vapor obstruction utilized in flexible electronics

NASA Astrophysics Data System (ADS)

Lee, Chang-Chun; Huang, Pei-Chen; He, Jing-Yan

2018-04-01

Organic light-emitting diode-based flexible and rollable displays have become a promising candidate for next-generation flexible electronics. For this reason, the design of surface multi-layered barriers should be optimized to enhance the long-term mechanical reliability of a flexible encapsulation that prevents the penetration of oxygen and vapor. In this study, finite element-based stress simulation was proposed to estimate the mechanical reliability of gas/vapor barrier design with low-k/silicon nitride (low-k/SiNx) stacking architecture. Consequently, stress-induced failure of critical thin films within the flexible display under various bending conditions must be considered. The feasibility of one pair SiO2/SiNx barrier design, which overcomes the complex lamination process, and the critical bending radius, which is decreased to 1.22 mm, were also examined. In addition, the influence of distance between neutral axes to the concerned layer surface dominated the induced-stress magnitude rather than the stress compliant mechanism provided from stacked low-k films.

Probing Temperature Inside Planar SOFC Short Stack, Modules, and Stack Series

NASA Astrophysics Data System (ADS)

Yu, Rong; Guan, Wanbing; Zhou, Xiao-Dong

2017-02-01

Probing temperature inside a solid oxide fuel cell (SOFC) stack lies at the heart of the development of high-performance and stable SOFC systems. In this article, we report our recent work on the direct measurements of the temperature in three types of SOFC systems: a 5-cell short stack, a 30-cell stack module, and a stack series consisting of two 30-cell stack modules. The dependence of temperature on the gas flow rate and current density was studied under a current sweep or steady-state operation. During the current sweep, the temperature inside the 5-cell stack decreased with increasing current, while it increased significantly at the bottom and top of the 30-cell stack. During a steady-state operation, the temperature of the 5-cell stack was stable while it was increased in the 30-cell stack. In the stack series, the maximum temperature gradient reached 190°C when the gas was not preheated. If the gas was preheated and the temperature gradient was reduced to 23°C in the stack series with the presence of a preheating gas and segmented temperature control, this resulted in a low degradation rate.

Fuel cell manifold sealing system

DOEpatents

Grevstad, Paul E.; Johnson, Carl K.; Mientek, Anthony P.

1980-01-01

A manifold-to-stack seal and sealing method for fuel cell stacks. This seal system solves the problem of maintaining a low leak rate manifold seal as the fuel cell stack undergoes compressive creep. The seal system eliminates the problem of the manifold-to-stack seal sliding against the rough stack surface as the stack becomes shorter because of cell creep, which relative motion destroys the seal. The seal system described herein utilizes a polymer seal frame firmly clamped between the manifold and the stack such that the seal frame moves with the stack. Thus, as the stack creeps, the seal frame creeps with it, and there is no sliding at the rough, tough to seal, stack-to-seal frame interface. Here the sliding is on a smooth easy to seal location between the seal frame and the manifold.

Method for producing a fuel cell manifold seal

DOEpatents

Grevstad, Paul E.; Johnson, Carl K.; Mientek, Anthony P.

1982-01-01

A manifold-to-stack seal and sealing method for fuel cell stacks. This seal system solves the problem of maintaining a low leak rate manifold seal as the fuel cell stack undergoes compressive creep. The seal system eliminates the problem of the manifold-to-stack seal sliding against the rough stack surface as the stack becomes shorter because of cell creep, which relative motion destroys the seal. The seal system described herein utilizes a polymer seal frame firmly clamped between the manifold and the stack such that the seal frame moves with the stack. Thus, as the stack creeps, the seal frame creeps with it, and there is no sliding at the rough, tough to seal, stack-to-seal frame interface. Here the sliding is on a smooth easy to seal location between the seal frame and the manifold.

Studies on complex π-π and T-stacking features of imidazole and phenyl/p-halophenyl units in series of 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides and their carbonitrile derivatives: Role of halogens in tuning of conformation

NASA Astrophysics Data System (ADS)

Das, Aniruddha

2017-11-01

5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides (N-phenyl AICA) (2a-e) and 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carbonitriles (N-phenyl AICN) (3a-e) had been synthesized. X-ray crystallographic studies of 2a-e and 3a-e had been performed to identify any distinct change in stacking patterns in their crystal lattice. Single crystal X-ray diffraction studies of 2a-e revealed π-π stack formations with both imidazole and phenyl/p-halophenyl units in anti and syn parallel-displaced (PD)-type dispositions. No π-π stacking of imidazole occurred when the halogen substituent is bromo or iodo; π-π stacking in these cases occurred involving phenyl rings only. The presence of an additional T-stacking had been observed in crystal lattices of 3a-e. Vertical π-π stacking distances in anti-parallel PD-type arrangements as well as T-stacking distances had shown stacking distances short enough to impart stabilization whereas syn-parallel stacking arrangements had got much larger π-π stacking distances to belie any syn-parallel stacking stabilization. DFT studies had been pursued for quantifying the π-π stacking and T-stacking stabilization. The plotted curves for anti-parallel and T-stacked moieties had similarities to the 'Morse potential energy curve for diatomic molecule'. The minima of the curves corresponded to the most stable stacking distances and related energy values indicated stacking stabilization. Similar DFT studies on syn-parallel systems of 2b corresponded to no π-π stacking stabilization at all. Halogen-halogen interactions had also been observed to stabilize the compounds 2d, 2e and 3d. Nano-structural behaviour of the series of compounds 2a-e and 3a-e were thoroughly investigated.

Transient analysis of a solid oxide fuel cell stack with crossflow configuration

NASA Astrophysics Data System (ADS)

Yuan, P.; Liu, S. F.

2018-05-01

This study investigates the transient response of the cell temperature and current density of a solid oxide fuel cell having 6 stacks with crossflow configuration. A commercial software repeatedly solves the governing equations of each stack, and get the convergent results of the whole SOFC stack. The preliminary results indicate that the average current density of each stack is similar to others, so the power output between different stacks are uniform. Moreover, the average cell temperature among stacks is different, and the central stacks have higher temperature due to its harder heat dissipation. For the operating control, the cell temperature difference among stacks is worth to concern because the temperature difference will be over 10 °C in the analysis case. The increasing of the inlet flow rate of the fuel and air will short the transient state, increase the average current density, and drop the cell temperature difference among the stacks. Therefore, the inlet flow rate is an important factor for transient performance of a SOFC stack.

Diverter/bop system and method for a bottom supported offshore drilling rig

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

Roche, J.R.; Alexander, G.G.; Carbaugh, W.L.

1986-07-01

A system is described adapted for alternative use as a diverter or a blowout preventer for a bottom supported drilling rig and adapted for connection to a permanent housing attached to rig structural members beneath a drilling rig rotary table, the permanent housing having an outlet connectable to a rig fluid system flow line. The system consists of: a fluid flow controller having a controller housing with a lower cylindrical opening and an upper cylindrical opening and a vertical path therebetween and a first outlet passage and a second outlet passage provided in its wall, a packing element disposed withinmore » the controller housing, and annular piston means adapted for moving from a first position to a second position, whereby in the first position the piston means wall prevents interior fluid from communicating with the outlet passages in the controller housing wall and in the second position the piston means wall allows fluid communication of interior fluid with the outlet passages and urges the annular packing element to close about an object extending through the bore of the controller housing or to close the vertical flow path through through the controller housing in the absence of any object in the vertical flow path, means for connecting a vent line to the outlet passage provided in the controller housing wall, a lower telescoping spool having a lower joining means at its lower end for joining alternatively to structural casing or to a mandrel connected to a conductor string cemented within the structural casing and an upper connection means at its upper end for connection to the lower cylindrical opening of the fluid flow controller, and an upper telescoping spool having a lower connection means for connection to the upper cylindrical opening of the fluid flow controller.« less

Oil Biodegradation and Oil-Degrading Microbial Populations in Marsh Sediments Impacted by Oil from the Deepwater Horizon Well Blowout.

PubMed

Atlas, Ronald M; Stoeckel, Donald M; Faith, Seth A; Minard-Smith, Angela; Thorn, Jonathan R; Benotti, Mark J

2015-07-21

To study hydrocarbon biodegradation in marsh sediments impacted by Macondo oil from the Deepwater Horizon well blowout, we collected sediment cores 18-36 months after the accident at the marshes in Bay Jimmy (Upper Barataria Bay), Louisiana, United States. The highest concentrations of oil were found in the top 2 cm of sediment nearest the waterline at the shorelines known to have been heavily oiled. Although petroleum hydrocarbons were detectable, Macondo oil could not be identified below 8 cm in 19 of the 20 surveyed sites. At the one site where oil was detected below 8 cm, concentrations were low. Residual Macondo oil was already highly weathered at the start of the study, and the concentrations of individual saturated hydrocarbons and polycyclic aromatic hydrocarbons continued to decrease over the course of the study due to biodegradation. Desulfococcus oleovorans, Marinobacter hydrocarbonoclasticus, Mycobacterium vanbaalenii, and related mycobacteria were the most abundant oil-degrading microorganisms detected in the top 2 cm at the oiled sites. Relative populations of these taxa declined as oil concentrations declined. The diversity of the microbial community was low at heavily oiled sites compared to that of the unoiled reference sites. As oil concentrations decreased over time, microbial diversity increased and approached the diversity levels of the reference sites. These trends show that the oil continues to be biodegraded, and microbial diversity continues to increase, indicating ongoing overall ecological recovery.

Footprint of Deepwater Horizon blowout impact to deep-water coral communities

PubMed Central

Fisher, Charles R.; Hsing, Pen-Yuan; Kaiser, Carl L.; Yoerger, Dana R.; Roberts, Harry H.; Shedd, William W.; Cordes, Erik E.; Shank, Timothy M.; Berlet, Samantha P.; Saunders, Miles G.; Larcom, Elizabeth A.; Brooks, James M.

2014-01-01

On April 20, 2010, the Deepwater Horizon (DWH) blowout occurred, releasing more oil than any accidental spill in history. Oil release continued for 87 d and much of the oil and gas remained in, or returned to, the deep sea. A coral community significantly impacted by the spill was discovered in late 2010 at 1,370 m depth. Here we describe the discovery of five previously unknown coral communities near the Macondo wellhead and show that at least two additional coral communities were impacted by the spill. Although the oil-containing flocullent material that was present on corals when the first impacted community was discovered was largely gone, a characteristic patchy covering of hydrozoans on dead portions of the skeleton allowed recognition of impacted colonies at the more recently discovered sites. One of these communities was 6 km south of the Macondo wellhead and over 90% of the corals present showed the characteristic signs of recent impact. The other community, 22 km southeast of the wellhead between 1,850 and 1,950 m depth, was more lightly impacted. However, the discovery of this site considerably extends the distance from Macondo and depth range of significant impact to benthic macrofaunal communities. We also show that most known deep-water coral communities in the Gulf of Mexico do not appear to have been acutely impacted by the spill, although two of the newly discovered communities near the wellhead apparently not impacted by the spill have been impacted by deep-sea fishing operations. PMID:25071200

TRIGGER OF A BLOWOUT JET IN A SOLAR CORONAL MASS EJECTION ASSOCIATED WITH A FLARE

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

Li, Xiaohong; Yang, Shuhong; Chen, Huadong

2015-11-20

Using the multi-wavelength images and the photospheric magnetograms from the Solar Dynamics Observatory, we study the flare that was associated with the only coronal mass ejection (CME) in active region (AR) 12192. The eruption of a filament caused a blowout jet, and then an M4.0 class flare occurred. This flare was located at the edge of the AR instead of in the core region. The flare was close to the apparently “open” fields, appearing as extreme-ultraviolet structures that fan out rapidly. Due to the interaction between flare materials and “open” fields, the flare became an eruptive flare, leading to themore » CME. Then, at the same site of the first eruption, another small filament erupted. With the high spatial and temporal resolution Hα data from the New Vacuum Solar Telescope at the Fuxian Solar Observatory, we investigate the interaction between the second filament and the nearby “open” lines. The filament reconnected with the “open” lines, forming a new system. To our knowledge, the detailed process of this kind of interaction is reported for the first time. Then the new system rotated due to the untwisting motion of the filament, implying that the twist was transferred from the closed filament system to the “open” system. In addition, the twist seemed to propagate from the lower atmosphere to the upper layers and was eventually spread by the CME to the interplanetary space.« less

Interim Policy on Stack Height Regulatory Actions

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Q and A on Implementing the Revised Stack Height Regulation

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Tall Stack Policy and its Relationship With PSD

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Effect of Changing Stack Heights on PSD Modeling and Monitoring

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Scientific Research Program for Power, Energy, and Thermal Technologies. Task Order 0001: Power, Thermal and Control Technologies and Processes Experimental Research

DTIC Science & Technology

2015-08-01

and (b) physical property data collection Following film deposition (via PLD or radio frequency magnetron sputtering), to prevent unwanted...carried out using an in-house radio frequency induction hot press under vacuum at ~1 mTorr and temperatures of 650, 750 and 850 °C. Sintering time was 2...tape thickness 23 µm, lamination stack thickness 11 mm). Simulated magnetic flux density inside the core was ~0.1 T, and operating frequency was

Investigation of the characteristics of a stacked direct borohydride fuel cell for portable applications

NASA Astrophysics Data System (ADS)

Kim, Cheolhwan; Kim, Kyu-Jung; Ha, Man Yeong

To investigate the possibility of the portable application of a direct borohydride fuel cell (DBFC), weight reduction of the stack and high stacking of the cells are investigated for practical running conditions. For weight reduction, carbon graphite is adopted as the bipolar plate material even though it has disadvantages in tight stacking, which results in stacking loss from insufficient material strength. For high stacking, it is essential to have a uniform fuel distribution among cells and channels to maintain equal electric load on each cell. In particular, the design of the anode channel is important because active hydrogen generation causes non-uniformity in the fuel flow-field of the cells and channels. To reduce the disadvantages of stacking force margin and fuel maldistribution, an O-ring type-sealing system with an internal manifold and a parallel anode channel design is adopted, and the characteristics of a single and a five-cell fuel cell stack are analyzed. By adopting carbon graphite, the stack weight can be reduced by 4.2 times with 12% of performance degradation from the insufficient stacking force. When cells are stacked, the performance exceeds the single-cell performance because of the stack temperature increase from the reduction of the radiation area from the narrow stacking of cells.

Pressurized electrolysis stack with thermal expansion capability

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

Bourgeois, Richard Scott

The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, themore » electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.« less

Potentially Preventable Deaths Among the Five Leading Causes of Death - United States, 2010 and 2014.

PubMed

García, Macarena C; Bastian, Brigham; Rossen, Lauren M; Anderson, Robert; Miniño, Arialdi; Yoon, Paula W; Faul, Mark; Massetti, Greta; Thomas, Cheryll C; Hong, Yuling; Iademarco, Michael F

2016-11-18

Death rates by specific causes vary across the 50 states and the District of Columbia.* Information on differences in rates for the leading causes of death among states might help state health officials determine prevention goals, priorities, and strategies. CDC analyzed National Vital Statistics System data to provide national and state-specific estimates of potentially preventable deaths among the five leading causes of death in 2014 and compared these estimates with estimates previously published for 2010. Compared with 2010, the estimated number of potentially preventable deaths changed (supplemental material at https://stacks.cdc.gov/view/cdc/42472); cancer deaths decreased 25% (from 84,443 to 63,209), stroke deaths decreased 11% (from 16,973 to 15,175), heart disease deaths decreased 4% (from 91,757 to 87,950), chronic lower respiratory disease (CLRD) (e.g., asthma, bronchitis, and emphysema) deaths increased 1% (from 28,831 to 29,232), and deaths from unintentional injuries increased 23% (from 36,836 to 45,331). A better understanding of progress made in reducing potentially preventable deaths in the United States might inform state and regional efforts targeting the prevention of premature deaths from the five leading causes in the United States.

Lightweight Stacks of Direct Methanol Fuel Cells

NASA Technical Reports Server (NTRS)

Narayanan, Sekharipuram; Valdez, Thomas

2004-01-01

An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

Anode reactive bleed and injector shift control strategy

DOEpatents

Cai, Jun [Rochester, NY; Chowdhury, Akbar [Pittsford, NY; Lerner, Seth E [Honeoye Falls, NY; Marley, William S [Rush, NY; Savage, David R [Rochester, NY; Leary, James K [Rochester, NY

2012-01-03

A system and method for correcting a large fuel cell voltage spread for a split sub-stack fuel cell system. The system includes a hydrogen source that provides hydrogen to each split sub-stack and bleed valves for bleeding the anode side of the sub-stacks. The system also includes a voltage measuring device for measuring the voltage of each cell in the split sub-stacks. The system provides two levels for correcting a large stack voltage spread problem. The first level includes sending fresh hydrogen to the weak sub-stack well before a normal reactive bleed would occur, and the second level includes sending fresh hydrogen to the weak sub-stack and opening the bleed valve of the other sub-stack when the cell voltage spread is close to stack failure.

Plated lamination structures for integrated magnetic devices

DOEpatents

Webb, Bucknell C.

2014-06-17

Semiconductor integrated magnetic devices such as inductors, transformers, etc., having laminated magnetic-insulator stack structures are provided, wherein the laminated magnetic-insulator stack structures are formed using electroplating techniques. For example, an integrated laminated magnetic device includes a multilayer stack structure having alternating magnetic and insulating layers formed on a substrate, wherein each magnetic layer in the multilayer stack structure is separated from another magnetic layer in the multilayer stack structure by an insulating layer, and a local shorting structure to electrically connect each magnetic layer in the multilayer stack structure to an underlying magnetic layer in the multilayer stack structure to facilitate electroplating of the magnetic layers using an underlying conductive layer (magnetic or seed layer) in the stack as an electrical cathode/anode for each electroplated magnetic layer in the stack structure.

Determination of Algorithm Parallelism in NP Complete Problems for Distributed Architectures

DTIC Science & Technology

1990-03-05

12 structure STACK declare OpenStack (S-.NODE **TopPtr) -+TopPtrI FlushStack(S.-NODE **TopPtr) -*TopPtr PushOnStack(S-.NODE **TopPtr, ITEM *NewltemPtr...OfCoveringSets, CoveringSets, L, Best CoverTime, Vertex, Set3end SCND ADT B.26 structure STACKI declare OpenStack (S-NODE **TopPtr) -+TopPtr FlushStack(S

Studies on the π-π stacking features of imidazole units present in a series of 5-amino-1-alkylimidazole-4-carboxamides

NASA Astrophysics Data System (ADS)

Ray, Sibdas; Das, Aniruddha

2015-06-01

Reaction of 2-ethoxymethyleneamino-2-cyanoacetamide with primary alkyl amines in acetonitrile solvent affords 1-substituted-5-aminoimidazole-4-carboxamides. Single crystal X-ray diffraction studies of these imidazole compounds show that there are both anti-parallel and syn-parallel π-π stackings between two imidazole units in parallel-displaced (PD) conformations and the distance between two π-π stacked imidazole units depends mainly on the anti/ syn-parallel nature and to some extent on the alkyl group attached to N-1 of imidazole; molecules with anti-parallel PD-stacking arrangements of the imidazole units have got vertical π-π stacking distance short enough to impart stabilization whereas the imidazole unit having syn-parallel stacking arrangement have got much larger π-π stacking distances. DFT studies on a pair of anti-parallel imidazole units of such an AICA lead to curves for 'π-π stacking stabilization energy vs. π-π stacking distance' which have got similarity with the 'Morse potential energy diagram for a diatomic molecule' and this affords to find out a minimum π-π stacking distance corresponding to the maximum stacking stabilization energy between the pair of imidazole units. On the other hand, a DFT calculation based curve for 'π-π stacking stabilization energy vs. π-π stacking distance' of a pair of syn-parallel imidazole units is shown to have an exponential nature.

Modular fuel-cell stack assembly

DOEpatents

Patel, Pinakin [Danbury, CT; Urko, Willam [West Granby, CT

2008-01-29

A modular multi-stack fuel-cell assembly in which the fuel-cell stacks are situated within a containment structure and in which a gas distributor is provided in the structure and distributes received fuel and oxidant gases to the stacks and receives exhausted fuel and oxidant gas from the stacks so as to realize a desired gas flow distribution and gas pressure differential through the stacks. The gas distributor is centrally and symmetrically arranged relative to the stacks so that it itself promotes realization of the desired gas flow distribution and pressure differential.

Calculation of Blowout Gun Nozzle Temperatures

DTIC Science & Technology

1981-07-01

rt u <u p- a Tto> tocNTj- t^f^o a>t-^oo MOtr^ vOi-i (NtOt/J L/JOOO sOLOr -- t^vOOO "*L0 \\or^QO vot^o invot^ uosor-> O ir^ O ’ o oo O 00 f...Cmd 28150 Dequindre Road Warren, MI 48090 Project Manager Cannon Artillery Wpns Systems ATTN: DRCPM-CAWS US Army ARRADCOM Dover, NJ 07801...Director US Army TRADOC Systems Analysis Activity ATTN: ATAA-SL, Tech Lib White Sands Missile Range, NM 88002 Organization No. of Copies 1

Preliminary Transient Performance Data on the J73 Turbojet Engine. 3; Altitude, 45,000 Feet

NASA Technical Reports Server (NTRS)

McAulay, John E.; Wallner, Lewis E.

1953-01-01

A program was undertaken to determine the J73 turbojet engine compressor stall and surge characteristics and combustor blow-out limits enc ountered during transient engine operation. Data were obtained in the form of oscillograph traces showing the time history of several engi ne parameters with changes in engine fuel flow. The data presented in this report are for step and ramp changes in fuel flow at an altitude of 45,000 feet and flight Mach numbers of 0 and 0.8.

Electron self-injection and trapping into an evolving plasma bubble.

PubMed

Kalmykov, S; Yi, S A; Khudik, V; Shvets, G

2009-09-25

The blowout (or bubble) regime of laser wakefield acceleration is promising for generating monochromatic high-energy electron beams out of low-density plasmas. It is shown analytically and by particle-in-cell simulations that self-injection of the background plasma electrons into the quasistatic plasma bubble can be caused by slow temporal expansion of the bubble. Sufficient criteria for the electron trapping and bubble's expansion rate are derived using a semianalytic nonstationary Hamiltonian theory. It is further shown that the combination of bubble's expansion and contraction results in monoenergetic electron beams.

Accurate modeling of the hose instability in plasma wakefield accelerators

DOE PAGES

Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.; ...

2018-05-20

Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. Lastly, it paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

Aircraft accident report: NASA 712, Convair 990, N712NA, March Air Force Base, California, July 17, 1985, executive summary

NASA Technical Reports Server (NTRS)

Batthauer, Byron E.; Mccarthy, G. T.; Hannah, Michael; Hogan, Robert J.; Marlow, Frank J.; Reynard, William D.; Stoklosa, Janis H.; Yager, Thomas J.

1986-01-01

On July 17, l985, NASA 712, a Convair 990 aircraft, was destroyed by fire during an aborted takeoff at March Air Force Base in California. Material ejected from a blowout in the tires of the right main landing gear penetrated the right-wing fuel tank. The leaking fuel ignited. Fire engulfed the right wing and fuselage as the aircraft stopped its forward motion. The crew of four and the 15 scientists and technicians aboard escaped without serious injury.

Accurate modeling of the hose instability in plasma wakefield accelerators

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

Mehrling, T. J.; Benedetti, C.; Schroeder, C. B.

Hosing is a major challenge for the applicability of plasma wakefield accelerators and its modeling is therefore of fundamental importance to facilitate future stable and compact plasma-based particle accelerators. In this contribution, we present a new model for the evolution of the plasma centroid, which enables the accurate investigation of the hose instability in the nonlinear blowout regime. Lastly, it paves the road for more precise and comprehensive studies of hosing, e.g., with drive and witness beams, which were not possible with previous models.

Nature and magnitude of aromatic base stacking in DNA and RNA: Quantum chemistry, molecular mechanics, and experiment.

PubMed

Sponer, Jiří; Sponer, Judit E; Mládek, Arnošt; Jurečka, Petr; Banáš, Pavel; Otyepka, Michal

2013-12-01

Base stacking is a major interaction shaping up and stabilizing nucleic acids. During the last decades, base stacking has been extensively studied by experimental and theoretical methods. Advanced quantum-chemical calculations clarified that base stacking is a common interaction, which in the first approximation can be described as combination of the three most basic contributions to molecular interactions, namely, electrostatic interaction, London dispersion attraction and short-range repulsion. There is not any specific π-π energy term associated with the delocalized π electrons of the aromatic rings that cannot be described by the mentioned contributions. The base stacking can be rather reasonably approximated by simple molecular simulation methods based on well-calibrated common force fields although the force fields do not include nonadditivity of stacking, anisotropy of dispersion interactions, and some other effects. However, description of stacking association in condensed phase and understanding of the stacking role in biomolecules remain a difficult problem, as the net base stacking forces always act in a complex and context-specific environment. Moreover, the stacking forces are balanced with many other energy contributions. Differences in definition of stacking in experimental and theoretical studies are explained. Copyright © 2013 Wiley Periodicals, Inc.

Using a high-speed movie camera to evaluate slice dropping in clinical image interpretation with stack mode viewers.

PubMed

Yakami, Masahiro; Yamamoto, Akira; Yanagisawa, Morio; Sekiguchi, Hiroyuki; Kubo, Takeshi; Togashi, Kaori

2013-06-01

The purpose of this study is to verify objectively the rate of slice omission during paging on picture archiving and communication system (PACS) viewers by recording the images shown on the computer displays of these viewers with a high-speed movie camera. This study was approved by the institutional review board. A sequential number from 1 to 250 was superimposed on each slice of a series of clinical Digital Imaging and Communication in Medicine (DICOM) data. The slices were displayed using several DICOM viewers, including in-house developed freeware and clinical PACS viewers. The freeware viewer and one of the clinical PACS viewers included functions to prevent slice dropping. The series was displayed in stack mode and paged in both automatic and manual paging modes. The display was recorded with a high-speed movie camera and played back at a slow speed to check whether slices were dropped. The paging speeds were also measured. With a paging speed faster than half the refresh rate of the display, some viewers dropped up to 52.4 % of the slices, while other well-designed viewers did not, if used with the correct settings. Slice dropping during paging was objectively confirmed using a high-speed movie camera. To prevent slice dropping, the viewer must be specially designed for the purpose and must be used with the correct settings, or the paging speed must be slower than half of the display refresh rate.

MoS2 Negative-Capacitance Field-Effect Transistors with Subthreshold Swing below the Physics Limit.

PubMed

Liu, Xingqiang; Liang, Renrong; Gao, Guoyun; Pan, Caofeng; Jiang, Chunsheng; Xu, Qian; Luo, Jun; Zou, Xuming; Yang, Zhenyu; Liao, Lei; Wang, Zhong Lin

2018-05-21

The Boltzmann distribution of electrons induced fundamental barrier prevents subthreshold swing (SS) from less than 60 mV dec -1 at room temperature, leading to high energy consumption of MOSFETs. Herein, it is demonstrated that an aggressive introduction of the negative capacitance (NC) effect of ferroelectrics can decisively break the fundamental limit governed by the "Boltzmann tyranny". Such MoS 2 negative-capacitance field-effect transistors (NC-FETs) with self-aligned top-gated geometry demonstrated here pull down the SS value to 42.5 mV dec -1 , and simultaneously achieve superior performance of a transconductance of 45.5 μS μm and an on/off ratio of 4 × 10 6 with channel length less than 100 nm. Furthermore, the inserted HfO 2 layer not only realizes a stable NC gate stack structure, but also prevents the ferroelectric P(VDF-TrFE) from fatigue with robust stability. Notably, the fabricated MoS 2 NC-FETs are distinctly different from traditional MOSFETs. The on-state current increases as the temperature decreases even down to 20 K, and the SS values exhibit nonlinear dependence with temperature due to the implementation of the ferroelectric gate stack. The NC-FETs enable fundamental applications through overcoming the Boltzmann limit in nanoelectronics and open up an avenue to low-power transistors needed for many exciting long-endurance portable consumer products. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inflatable containment diaphragm for sealing and removing stacks

DOEpatents

Meskanick, G.R.; Rosso, D.T.

1993-04-13

A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

Inflatable containment diaphragm for sealing and removing stacks

DOEpatents

Meskanick, Gerald R.; Rosso, David T.

1993-01-01

A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

User Driven Image Stacking for ODI Data and Beyond via a Highly Customizable Web Interface

NASA Astrophysics Data System (ADS)

Hayashi, S.; Gopu, A.; Young, M. D.; Kotulla, R.

2015-09-01

While some astronomical archives have begun serving standard calibrated data products, the process of producing stacked images remains a challenge left to the end-user. The benefits of astronomical image stacking are well established, and dither patterns are recommended for almost all observing targets. Some archives automatically produce stacks of limited scientific usefulness without any fine-grained user or operator configurability. In this paper, we present PPA Stack, a web based stacking framework within the ODI - Portal, Pipeline, and Archive system. PPA Stack offers a web user interface with built-in heuristics (based on pointing, filter, and other metadata information) to pre-sort images into a set of likely stacks while still allowing the user or operator complete control over the images and parameters for each of the stacks they wish to produce. The user interface, designed using AngularJS, provides multiple views of the input dataset and parameters, all of which are synchronized in real time. A backend consisting of a Python application optimized for ODI data, wrapped around the SWarp software, handles the execution of stacking workflow jobs on Indiana University's Big Red II supercomputer, and the subsequent ingestion of the combined images back into the PPA archive. PPA Stack is designed to enable seamless integration of other stacking applications in the future, so users can select the most appropriate option for their science.

Develop and test fuel cell powered on-site integrated total energy systems. Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Kaufman, A.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

1984-01-01

Two 25-cell, 13 inch x 23 inch (4kW) stacks were started up to evaluate the reliability of component and stack technology developed through the end of 1983. Both stacks started up well and are running satisfactorily on hydrogen-air after 1900 hours and 800 hours, respectively. A synthetic-reformat mixing station is nearing completion, and both stacks will be operated on reformate fuel. A stack-protection control system was placed in operation for Stack No. 2, and a similar set-up is in preparation for Stack No. 1. This system serves to change operating conditions or shut the stack down to avoid deleterious effects from nonstack-related upsets. The capability will greatly improve changes of obtaining meaningful long-term test data.

Short protection device for stack of electrolytic cells

DOEpatents

Katz, Murray; Schroll, Craig R.

1985-10-22

Electrical short protection is provided in an electrolytic cell stack by the combination of a thin, nonporous ceramic shield and a noble metal foil disposed on opposite sides of the sealing medium in a gas manifold gasket. The thin ceramic shield, such as alumina, is placed between the porous gasket and the cell stack face at the margins of the negative end plate to the most negative cells to impede ion current flow. The noble metal foil, for instance gold, is electrically coupled to the negative potential of the stack to collect positive ions at a harmless location away from the stack face. Consequently, corrosion products from the stack structure deposit on the foil rather than on the stack face to eliminate electrical shorting of cells at the negative end of the stack.

Stacking with stochastic cooling

NASA Astrophysics Data System (ADS)

Caspers, Fritz; Möhl, Dieter

2004-10-01

Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

Pressure Dome for High-Pressure Electrolyzer

NASA Technical Reports Server (NTRS)

Norman, Timothy; Schmitt, Edwin

2012-01-01

A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom segment and is trapped by the flange on the top dome segment when these components are bolted together with high-strength bolts. The pressure dome has several unique features. It is made (to ASME Pressure Vessel guidelines) in a high-strength aluminum alloy with the strength of stainless steel and the weight benefits of aluminum. The flange of the upper dome portion contains specially machined flats for mounting the dome, and other flats dedicated to the special feedthroughs for electrical connections. A pressure dome can be increased in length to house larger stacks (more cells) of the same diameter with the simple addition of a cylindrical segment. To aid in dome assembly, two stainless steel rings are employed. One is used beneath the heads of the high-strength bolts in lieu of individual hardened washers, and another is used instead of individual nuts. Like electrolyzers could be operated at low or high pressures simply by operating the electrolyzer outside or inside a pressurized dome.

Sampled-time control of a microbial fuel cell stack

NASA Astrophysics Data System (ADS)

Boghani, Hitesh C.; Dinsdale, Richard M.; Guwy, Alan J.; Premier, Giuliano C.

2017-07-01

Research into microbial fuel cells (MFCs) has reached the point where cubic metre-scale systems and stacks are being built and tested. Apart from performance enhancement through catalysis, materials and design, an important research area for industrial applicability is stack control, which can enhance MFCs stack power output. An MFC stack is controlled using a sampled-time digital control strategy, which has the advantage of intermittent operation with consequent power saving, and when used in a hybrid series stack connectivity, can avoid voltage reversals. A MFC stack comprising four tubular MFCs was operated hydraulically in series. Each MFC was connected to an independent controller and the stack was connected electrically in series, creating a hybrid-series connectivity. The voltage of each MFC in the stack was controlled such that the overall series stack voltage generated was the algebraic sum (1.26 V) of the individual MFC voltages (0.32, 0.32, 0.32 and 0.3). The controllers were able to control the individual voltages to the point where 2.52 mA was drawn from the stack at a load of 499.9 Ω (delivering 3.18 mW). The controllers were able to reject the disturbances and perturbations caused by electrical loading, temperature and substrate concentration.

Microstructural characterization of high-manganese austenitic steels with different stacking fault energies

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

Sato, Shigeo, E-mail: s.sato@imr.tohoku.ac.jp; Kwon, Eui-Pyo; Imafuku, Muneyuki

Microstructures of tensile-deformed high-manganese austenitic steels exhibiting twinning-induced plasticity were analyzed by electron backscatter diffraction pattern observation and X-ray diffraction measurement to examine the influence of differences in their stacking fault energies on twinning activity during deformation. The steel specimen with the low stacking fault energy of 15 mJ/m{sup 2} had a microstructure with a high population of mechanical twins than the steel specimen with the high stacking fault energy (25 mJ/m{sup 2}). The <111> and <100> fibers developed along the tensile axis, and mechanical twinning occurred preferentially in the <111> fiber. The Schmid factors for slip and twinning deformationsmore » can explain the origin of higher twinning activity in the <111> fiber. However, the high stacking fault energy suppresses the twinning activity even in the <111> fiber. A line profile analysis based on the X-ray diffraction data revealed the relationship between the characteristics of the deformed microstructures and the stacking fault energies of the steel specimens. Although the variation in dislocation density with the tensile deformation is not affected by the stacking fault energies, the effect of the stacking fault energies on the crystallite size refinement becomes significant with a decrease in the stacking fault energies. Moreover, the stacking fault probability, which was estimated from a peak-shift analysis of the 111 and 200 diffractions, was high for the specimen with low stacking fault energy. Regardless of the difference in the stacking fault energies of the steel specimens, the refined crystallite size has a certain correlation with the stacking fault probability, indicating that whether the deformation-induced crystallite-size refinement occurs depends directly on the stacking fault probability rather than on the stacking fault energies in the present steel specimens. - Highlights: {yields} We studied effects of stacking fault energies on deformed microstructures of steels. {yields} Correlations between texture and occurrence of mechanical twinning are discussed. {yields} Evolutions of dislocations and crystallite are analyzed by line profile analysis.« less

Principles for Instructional Stack Development in HyperCard.

ERIC Educational Resources Information Center

McEneaney, John E.

The purpose of this paper is to provide information about obtaining and using HyperCard stacks that introduce users to principles of stack development. The HyperCard stacks described are available for downloading free of charge from a server at Indiana University South Bend. Specific directions are given for stack use, with advice for beginners. A…

40 CFR 60.1775 - What types of stack tests must I conduct?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What types of stack tests must I...-Stack Testing § 60.1775 What types of stack tests must I conduct? Conduct initial and annual stack tests to measure the emission levels of dioxins/furans, cadmium, lead, mercury, particulate matter, opacity...

40 CFR 60.1775 - What types of stack tests must I conduct?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What types of stack tests must I...-Stack Testing § 60.1775 What types of stack tests must I conduct? Conduct initial and annual stack tests to measure the emission levels of dioxins/furans, cadmium, lead, mercury, particulate matter, opacity...

40 CFR 75.72 - Determination of NOX mass emissions for common stack and multiple stack configurations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the hourly stack flow rate (in scfh). Only one methodology for determining NOX mass emissions shall be...-diluent continuous emissions monitoring system and a flow monitoring system in the common stack, record... maintain a flow monitoring system and diluent monitor in the duct to the common stack from each unit; or...

Ultrathin Optical Panel And A Method Of Making An Ultrathin Optical Panel.

DOEpatents

Biscardi, Cyrus; Brewster, Calvin; DeSanto, Leonard; Veligdan, James T.

2005-02-15

An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

Ultrathin Optical Panel And A Method Of Making An Ultrathin Optical Panel.

DOEpatents

Biscardi, Cyrus; Brewster, Calvin; DeSanto, Leonard; Veligdan, James T.

2005-05-17

An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

Ultrathin optical panel and a method of making an ultrathin optical panel

DOEpatents

Biscardi, Cyrus; Brewster, Calvin; DeSanto, Leonard; Veligdan, James T.

2003-02-11

An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

Ultrathin optical panel and a method of making an ultrathin optical panel

DOEpatents

Biscardi, Cyrus; Brewster, Calvin; DeSanto, Leonard; Veligdan, James T.

2001-10-09

An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

Ultrathin optical panel and a method of making an ultrathin optical panel

DOEpatents

Biscardi, Cyrus; Brewster, Calvin; DeSanto, Leonard; Veligdan, James T.

2002-01-01

An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated With a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

Complex and noncentrosymmetric stacking of layered metal dichalcogenide materials created by screw dislocations

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

Shearer, Melinda J.; Samad, Leith; Zhang, Yi

The interesting and tunable properties of layered metal dichalcogenides heavily depend on their phase and layer stacking. Here, we show and explain how the layer stacking and physical properties of WSe 2 are influenced by screw dislocations. A one-to-one correlation of atomic force microscopy and high- and low-frequency Raman spectroscopy of many dislocated WSe 2 nanoplates reveals variations in the number and shapes of dislocation spirals and different layer stackings that are determined by the number, rotation, and location of the dislocations. Plates with triangular dislocation spirals form noncentrosymmetric stacking that gives rise to strong second-harmonic generation and enhanced photoluminescence,more » plates with hexagonal dislocation spirals form the bulk 2H layer stacking commonly observed, and plates containing mixed dislocation shapes have intermediate noncentrosymmetric stackings with mixed properties. Multiple dislocation cores and other complexities can lead to more complex stackings and properties. Finally, these previously unobserved properties and layer stackings in WSe 2 will be interesting for spintronics and valleytronics.« less

Complex and noncentrosymmetric stacking of layered metal dichalcogenide materials created by screw dislocations

DOE PAGES

Shearer, Melinda J.; Samad, Leith; Zhang, Yi; ...

2017-02-08

The interesting and tunable properties of layered metal dichalcogenides heavily depend on their phase and layer stacking. Here, we show and explain how the layer stacking and physical properties of WSe 2 are influenced by screw dislocations. A one-to-one correlation of atomic force microscopy and high- and low-frequency Raman spectroscopy of many dislocated WSe 2 nanoplates reveals variations in the number and shapes of dislocation spirals and different layer stackings that are determined by the number, rotation, and location of the dislocations. Plates with triangular dislocation spirals form noncentrosymmetric stacking that gives rise to strong second-harmonic generation and enhanced photoluminescence,more » plates with hexagonal dislocation spirals form the bulk 2H layer stacking commonly observed, and plates containing mixed dislocation shapes have intermediate noncentrosymmetric stackings with mixed properties. Multiple dislocation cores and other complexities can lead to more complex stackings and properties. Finally, these previously unobserved properties and layer stackings in WSe 2 will be interesting for spintronics and valleytronics.« less

Estimation of bioavailability of metals from drilling mud barite.

PubMed

Neff, Jerry M

2008-04-01

Drilling mud and associated drill cuttings are the largest volume wastes associated with drilling of oil and gas wells and often are discharged to the ocean from offshore drilling platforms. Barite (BaSO4) often is added as a weighting agent to drilling muds to counteract pressure in the geologic formations being drilled, preventing a blowout. Some commercial drilling mud barites contain elevated (compared to marine sediments) concentrations of several metals. The metals, if bioavailable, may harm the local marine ecosystem. The bioavailable fraction of metals is the fraction that dissolves from the nearly insoluble, solid barite into seawater or sediment porewater. Barite-seawater and barite-porewater distribution coefficients (Kd) were calculated for determining the predicted environmental concentration (PEC; the bioavailable fraction) of metals from drilling mud barite in the water column and sediments, respectively. Values for Kdbarite-seawater and Kdbarite-porewater were calculated for barium, cadmium, chromium, copper, mercury, lead, and zinc in different grades of barite. Log Kdbarite-seawater values were higher (solubility was lower) for metals in the produced water plume than log Kdbarite-porewater values for metals in sediments. The most soluble metals were cadmium and zinc and the least soluble were mercury and copper. Log Kd values can be used with data on concentrations of metals in barite and of barite in the drilling mud-cuttings plume and in bottom sediments to calculate PECseawater and PECsediment.

Risk Management at NASA and Its Applicability to the Oil and Gas Industry

NASA Technical Reports Server (NTRS)

Kaplan, David

2018-01-01

NASA has a world-class capability for quantitatively assessing the risk of highly-complex, isolated engineering structures operated in extremely hostile environments. In particular, the International Space Station (ISS) represents a reasonable risk analog for High Pressure, High Temperature drilling and production operations on deepwater rigs. Through a long-term U.S. Government Interagency Agreement, BSEE has partnered with NASA to modify NASA's Probabilistic Risk Assessment (PRA) capabilities for application to deepwater drilling and production operations. The immediate focus of the activity will be to modify NASA PRA Procedure Guides and Methodology Documents to make them applicable to the Oil &Gas Industry. The next step will be for NASA to produce a PRA for a critical drilling system component, such as a Blowout Preventer (BOP). Subsequent activities will be for NASA and industry partners to jointly develop increasingly complex PRA's that analyze other critical drilling and production system components, including both hardware and human reliability. In the presentation, NASA will provide the objectives, schedule, and current status of its PRA activities for BSEE. Additionally, NASA has a Space Act Agreement with Anadarko Petroleum Corporation to develop a PRA for a generic 20K BOP. NASA will summarize some of the preliminary insights gained to date from that 20K BOP PRA as an example of the distinction between quantitative versus qualitative risk assessment.

Development of a high power density 2.5 kW class solid oxide fuel cell stack

NASA Astrophysics Data System (ADS)

Yokoo, M.; Mizuki, K.; Watanabe, K.; Hayashi, K.

2011-10-01

We have developed a 2.5 kW class solid oxide fuel cell stack. It is constructed by combining 70 power generation units, each of which is composed of an anode-supported planar cell and separators. The power generation unit for the 2.5 kW class stack were designed so that the height of the unit were scaled down by 2/3 of that for our conventional 1.5 kW class stack. The power generation unit for the 2.5 kW class stack provided the same output as the unit used for the conventional 1.5 kW class stack, which means that power density per unit volume of the 2.5 kW class stack was 50% greater than that of the conventional 1.5 kW class stack.

Manifold gasket accommodating differential movement of fuel cell stack

DOEpatents

Kelley, Dana A.; Farooque, Mohammad

2007-11-13

A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.

Electrochemical cell stack assembly

DOEpatents

Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

2010-06-22

Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

Slip-stacking Dynamics for High-Power Proton Beams at Fermilab

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

Eldred, Jeffrey Scott

Slip-stacking is a particle accelerator configuration used to store two particle beams with different momenta in the same ring. The two beams are longitudinally focused by two radiofrequency (RF) cavities with a small frequency difference between them. Each beam is synchronized to one RF cavity and perturbed by the other RF cavity. Fermilab uses slip-stacking in the Recycler so as to double the power of the 120 GeV proton beam in the Main Injector. This dissertation investigates the dynamics of slip-stacking beams analytically, numerically and experimentally. In the analytic analysis, I find the general trajectory of stable slip-stacking particles andmore » identify the slip-stacking parametric resonances. In the numerical analysis, I characterize the stable phase-space area and model the particle losses. In particular, I evaluate the impact of upgrading the Fermilab Booster cycle-rate from 15 Hz to 20 Hz as part of the Proton Improvement Plan II (PIP-II). The experimental analysis is used to verify my approach to simulating slip-stacking loss. I design a study for measuring losses from the longitudinal single-particle dynamics of slip-stacking as a function of RF cavity voltage and RF frequency separation. I further propose the installation of a harmonic RF cavity and study the dynamics of this novel slip-stacking configuration. I show the harmonic RF cavity cancels out parametric resonances in slip-stacking, reduces emittance growth during slip-stacking, and dramatically enhances the stable phase-space area. The harmonic cavity is expected to reduce slip-stacking losses to far exceed PIP-II requirements. These results raise the possibility of extending slip-stacking beyond the PIP-II era.« less

Observational and Model Analysis of a Two-ribbon Flare Possibly Induced by a Neighboring Blowout Jet

NASA Astrophysics Data System (ADS)

Joshi, Bhuwan; Thalmann, Julia K.; Mitra, Prabir K.; Chandra, Ramesh; Veronig, Astrid M.

2017-12-01

In this paper, we present unique observations of a blowout coronal jet that possibly triggered a two-ribbon confined C1.2 flare in bipolar solar active region NOAA 12615 on 2016 December 5. The jet activity initiates at chromospheric/transition region heights with a small brightening that eventually increases in volume, with well-developed standard morphological jet features, viz., base and spire. The spire widens up with a collimated eruption of cool and hot plasma components, observed in the 304 and 94 Å channels of AIA, respectively. The speed of the plasma ejection, which forms the jet’s spire, was higher for the hot component (˜200 km s-1) than the cooler one (˜130 km s-1). The NLFF model of coronal fields at the pre- and post-jet phases successfully reveals openings of previously closed magnetic field lines with a rather inclined/low-lying jet structure. The peak phase of the jet emission is followed by the development of a two-ribbon flare that shows coronal loop emission in HXRs up to ˜25 keV energy. The coronal magnetic fields rooted at the location of EUV flare ribbons, derived from the NLFF model, demonstrate the pre-flare phase to exhibit an “X-type” configuration, while the magnetic fields at the post-flare phase are more or less oriented parallel. Comparisons of multi-wavelength measurements with the magnetic field extrapolations suggest that the jet activity likely triggered the two-ribbon flare by perturbing the field in the interior of the active region.

Carbon Composition of Particulate Organic Carbon in the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Rogers, K.; Montoya, J. P.; Weber, S.; Bosman, S.; Chanton, J.

2016-02-01

The Deepwater Horizon blowout released 5.0x1011 g C from gaseous hydrocarbons and up to 6.0x1011g C from oil into the water column. Another carbon source, adding daily to the water column, leaks from the natural hydrocarbon seeps that pepper the seafloor of the Gulf of Mexico. How much of this carbon from the DWH and natural seeps is assimilated into particulate organic carbon (POC) in the water column? We filtered seawater collected in 2010, 2012, and 2013 from seep and non-seep sites, collecting POC on 0.7µm glass microfiber filters and analyzing the POC for stable and radiocarbon isotopes. Mixing models based on carbon isotopic endmembers of methane, oil, and modern production were used to estimate the percentage of hydrocarbon incorporated into POC. Significant differences were seen between POC from shallow and deep waters and between POC collected from seep, non-seep, and blowout sites; however yearly differences were not as evident suggesting the GOM has a consistent supply of depleted carbon. Stable carbon isotopes signatures of POC in the Gulf averaged -23.7±2.5‰ for shallow samples and -26.65±2.9‰ for deep POC samples, while radiocarbon signatures averaged -100.4±146.1‰ for shallow and -394.6±197‰ for deep samples. POC in the northern Gulf are composed of 23-91% modern carbon, 2-21% methane, and 0-71% oil. Oil plays a major role in the POC composition of the GOM, especially at the natural seep GC600.

Intrusion dynamics of particle plumes in stratified water with weak crossflow: Application to deep ocean blowouts

NASA Astrophysics Data System (ADS)

Wang, Dayang; Adams, E. Eric

2016-06-01

We present an experimental study of particle plumes in ambient stratification and a mild current. In an inverted framework, the results describe the fate of oil droplets released from a deep ocean blowout. A continuous stream of dense glass beads was released from a carriage towed in a salt-stratified tank. Nondimensional particle slip velocity UN ranged from 0.1 to 1.9, and particles with UN ≤ 0.5 were observed to enter the intrusion layer. The spatial distributions of beads, collected on a bottom sled towed with the source, present a Gaussian distribution in the transverse direction and a skewed distribution in the along-current direction. Dimensions of the distributions increase with decreasing UN. The spreading relations can be used as input to far-field models describing subsequent transport of particles or, in an inverted framework, oil droplets. The average particle settling velocity, Uave, was found to exceed the individual particle slip velocity, Us, which is attributed to the initial plume velocity near the point of release. Additionally, smaller particles exhibit a "group" or "secondary plume" effect as they exit the intrusion as a swarm. The secondary effect becomes more prominent as UN decreases, and might help explain observations from the 2000 Deep Spill field experiment where oil was found to surface more rapidly than predicted based on Us. An analytical model predicting the particle deposition patterns was validated against experimental measurements, and used to estimate near-field oil transport under the Deepwater Horizon spill conditions, with/without chemical dispersants.

Scaling of energy absorbing composite plates

NASA Technical Reports Server (NTRS)

Jackson, Karen; Morton, John; Traffanstedt, Catherine; Boitnott, Richard

1992-01-01

The energy absorption response and crushing characteristics of geometrically scaled graphite-Kevlar epoxy composite plates were investigated. Three different trigger mechanisms including chamfer, notch, and steeple geometries were incorporated into the plate specimens to initiate crushing. Sustained crushing was achieved with a simple test fixture which provided lateral support to prevent global buckling. Values of specific sustained crushing stress (SSCS) were obtained which were comparable to values reported for tube specimens from previously published data. Two sizes of hybrid plates were fabricated; a baseline or model plate, and a full-scale plate with in-plane dimensions scaled by a factor of two. The thickness dimension of the full-scale plates was increased using two different techniques; the ply-level method in which each ply orientation in the baseline laminate stacking sequence is doubled, and the sublaminate technique in which the baseline laminate stacking sequence is repeated as a group. Results indicated that the SSCS is independent of trigger mechanism geometry. However, a reduction in the SSCS of 10-25 percent was observed for the full-scale plates as compared with the baseline specimens, indicating a scaling effect in the crushing response.

Scaling of energy absorbing composite plates

NASA Technical Reports Server (NTRS)

Jackson, Karen; Lavoie, J. Andre; Morton, John

1994-01-01

The energy absorption response and crushing characteristics of geometrically scaled graphite-Kevlar epoxy composite plates were investigated. Two different trigger mechanisms including notch, and steeple geometries were incorporated into the plate specimens to initiate crushing. Sustained crushing was achieved with a new test fixture which provided lateral support to prevent global buckling. Values of specific sustained crushing stress (SSCS) were obtained which were lower than values reported for tube specimens from previously published data. Two sizes of hybrid plates were fabricated; a baseline or model plate, and a full-scale plate with inplane dimensions scaled by a factor of two. The thickness dimension of the full-scale plates was increased using two different techniques: the ply-level method in which each ply orientation in the baseline laminate stacking sequence is doubled, and the sublaminate technique in which the baseline laminate stacking sequence is repeated as a group. Results indicated that the SSCS has a small dependence on trigger mechanism geometry. However, a reduction in the SSCS of 10-25% was observed for the full-scale plates as compared with the baseline specimens, indicating a scaling effect in the crushing response.

Scaling of energy absorbing composite plates

NASA Astrophysics Data System (ADS)

Jackson, Karen; Morton, John; Traffanstedt, Catherine; Boitnott, Richard

The energy absorption response and crushing characteristics of geometrically scaled graphite-Kevlar epoxy composite plates were investigated. Three different trigger mechanisms including chamfer, notch, and steeple geometries were incorporated into the plate specimens to initiate crushing. Sustained crushing was achieved with a simple test fixture which provided lateral support to prevent global buckling. Values of specific sustained crushing stress (SSCS) were obtained which were comparable to values reported for tube specimens from previously published data. Two sizes of hybrid plates were fabricated; a baseline or model plate, and a full-scale plate with in-plane dimensions scaled by a factor of two. The thickness dimension of the full-scale plates was increased using two different techniques; the ply-level method in which each ply orientation in the baseline laminate stacking sequence is doubled, and the sublaminate technique in which the baseline laminate stacking sequence is repeated as a group. Results indicated that the SSCS is independent of trigger mechanism geometry. However, a reduction in the SSCS of 10-25 percent was observed for the full-scale plates as compared with the baseline specimens, indicating a scaling effect in the crushing response.

Novel ferrocene-anchored ZnO nanoparticle/carbon nanotube assembly for glucose oxidase wiring: application to a glucose/air fuel cell.

PubMed

Haddad, Raoudha; Mattei, Jean-Gabriel; Thery, Jessica; Auger, Aurélien

2015-06-28

Glucose oxidase (GOx) is immobilized on ZnO nanoparticle-modified electrodes. The immobilized glucose oxidase shows efficient mediated electron transfer with ZnO nanoparticles to which the ferrocenyl moiety is π-stacked into a supramolecular architecture. The constructed ZnO-Fc/CNT modified electrode exhibits high ferrocene surface coverage, preventing any leakage of the π-stacked ferrocene from the newly described ZnO hybrid nanoparticles. The use of the new architecture of ZnO supported electron mediators to shuttle electrons from the redox centre of the enzyme to the surface of the working electrode can effectively bring about successful glucose oxidation. These modified electrodes evaluated as a highly efficient architecture provide a catalytic current for glucose oxidation and are integrated in a specially designed glucose/air fuel cell prototype using a conventional platinum-carbon (Pt/C) cathode at physiological pH (7.0). The obtained architecture leads to a peak power density of 53 μW cm(-2) at 300 mV for the Nafion® based biofuel cell under "air breathing" conditions at room temperature.

Design and simulation of novel flow field plate geometry for proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Ruan, Hanxia; Wu, Chaoqun; Liu, Shuliang; Chen, Tao

2016-10-01

Bipolar plate is one of the many important components of proton exchange membrane fuel cell (PEMFC) stacks as it supplies fuel and oxidant to the membrane-electrode assembly (MEA), removes water, collects produced current and provides mechanical support for the single cells in the stack. The flow field design of a bipolar plate greatly affects the performance of a PEMFC. It must uniformly distribute the reactant gases over the MEA and prevent product water flooding. This paper aims at improving the fuel cell performance by optimizing flow field designs and flow channel configurations. To achieve this, a novel biomimetic flow channel for flow field designs is proposed based on Murray's Law. Computational fluid dynamics based simulations were performed to compare three different designs (parallel, serpentine and biomimetic channel, respectively) in terms of current density distribution, power density distribution, pressure distribution, temperature distribution, and hydrogen mass fraction distribution. It was found that flow field designs with biomimetic flow channel perform better than that with convectional flow channel under the same operating conditions.

Avoiding chromium transport from stainless steel interconnects into contact layers and oxygen electrodes in intermediate temperature solid oxide electrolysis stacks

NASA Astrophysics Data System (ADS)

Schlupp, Meike V. F.; Kim, Ji Woo; Brevet, Aude; Rado, Cyril; Couturier, Karine; Vogt, Ulrich F.; Lefebvre-Joud, Florence; Züttel, Andreas

2014-12-01

We investigated the ability of (La0.8Sr0.2)(Mn0.5Co0.5)O3-δ (LSMC) and La(Ni0.6Fe0.4)O3-δ (LNF) contact coatings to avoid the transport of Cr from steel interconnects to solid oxide electrolysis electrodes, especially to the anode. The transport of chromium from commercial Crofer 22 APU (ThyssenKrupp) and K41X (AISI441, Aperam Isbergues) steels through LSMC and LNF contact coatings into adjacent (La0.8Sr0.2)MnO3-δ (LSM) oxygen electrodes was investigated in an oxygen atmosphere at 700 °C. Chromium concentrations of up to 4 atom% were detected in the contact coatings after thermal treatments for 3000 h, which also lead to the presence of chromium in adjacent LSM electrodes. Introduction of a dense (Co,Mn)3O4 coating between steel and contact coating was necessary to prevent the diffusion of chromium into contact coatings and electrodes and should lead to extended stack performance and lifetime.

Opinion On Whether Making a Bypass Stack Functional Constitutes Routine Repair and Maintenance

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Response to Kay Phillips Regarding a Review on the Stack Height Regulations and Accompanying Preamble Language

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Hot air drum evaporator. [Patent application

DOEpatents

Black, R.L.

1980-11-12

An evaporation system for aqueous radioactive waste uses standard 30 and 55 gallon drums. Waste solutions form cascading water sprays as they pass over a number of trays arranged in a vertical stack within a drum. Hot dry air is circulated radially of the drum through the water sprays thereby removing water vapor. The system is encased in concrete to prevent exposure to radioactivity. The use of standard 30 and 55 gallon drums permits an inexpensive compact modular design that is readily disposable, thus eliminating maintenance and radiation build-up problems encountered with conventional evaporation systems.

Hot air drum evaporator

DOEpatents

Black, Roger L.

1981-01-01

An evaporation system for aqueous radioactive waste uses standard 30 and 55 gallon drums. Waste solutions form cascading water sprays as they pass over a number of trays arranged in a vertical stack within a drum. Hot dry air is circulated radially of the drum through the water sprays thereby removing water vapor. The system is encased in concrete to prevent exposure to radioactivity. The use of standard 30 and 55 gallon drums permits an inexpensive compact modular design that is readily disposable, thus eliminating maintenance and radiation build-up problems encountered with conventional evaporation systems.

Cache-based error recovery for shared memory multiprocessor systems

NASA Technical Reports Server (NTRS)

Wu, Kun-Lung; Fuchs, W. Kent; Patel, Janak H.

1989-01-01

A multiprocessor cache-based checkpointing and recovery scheme for of recovering from transient processor errors in a shared-memory multiprocessor with private caches is presented. New implementation techniques that use checkpoint identifiers and recovery stacks to reduce performance degradation in processor utilization during normal execution are examined. This cache-based checkpointing technique prevents rollback propagation, provides for rapid recovery, and can be integrated into standard cache coherence protocols. An analytical model is used to estimate the relative performance of the scheme during normal execution. Extensions that take error latency into account are presented.

Environmental barrier material for organic light emitting device and method of making

DOEpatents

Graff, Gordon L [West Richland, WA; Gross, Mark E [Pasco, WA; Affinito, John D [Kennewick, WA; Shi, Ming-Kun [Richland, WA; Hall, Michael [West Richland, WA; Mast, Eric [Richland, WA

2003-02-18

An encapsulated organic light emitting device. The device includes a first barrier stack comprising at least one first barrier layer and at least one first polymer layer. There is an organic light emitting layer stack adjacent to the first barrier stack. A second barrier stack is adjacent to the organic light emitting layer stack. The second barrier stack has at least one second barrier layer and at least one second polymer layer. A method of making the encapsulated organic light emitting device is also provided.

Helping Students Design HyperCard Stacks.

ERIC Educational Resources Information Center

Dunham, Ken

1995-01-01

Discusses how to teach students to design HyperCard stacks. Highlights include introducing HyperCard, developing storyboards, introducing design concepts and scripts, presenting stacks, evaluating storyboards, and continuing projects. A sidebar presents a HyperCard stack evaluation form. (AEF)

23. Brick coke quencher, brick stack, metal stack to right, ...

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

23. Brick coke quencher, brick stack, metal stack to right, coke gas pipe to left; in background, BOF building, limestone piles, Levy's Slag Dump. Looking north/northwest - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

Cool white light-emitting three stack OLED structures for AMOLED display applications.

PubMed

Springer, Ramon; Kang, Byoung Yeop; Lampande, Raju; Ahn, Dae Hyun; Lenk, Simone; Reineke, Sebastian; Kwon, Jang Hyuk

2016-11-28

This paper demonstrates 2-stack and 3-stack white organic light-emitting diodes (WOLEDs) with fluorescent blue and phosphorescent yellow emissive units. The 2-stack and 3-stack WOLED comprises blue-yellow and blue-blue-yellow (blue-yellow-blue) combinations. The position of the yellow emitter and possible cavity lengths in different stack architectures are theoretically and experimentally investigated to reach Commission Internationale de L'Eclairage (CIE) coordinates of near (0.333/0.333). Here, a maximum external quantum efficiency (EQE) of 23.6% and current efficiency of 62.2 cd/A at 1000 cd/m² as well as suitable CIE color coordinates of (0.335/0.313) for the blue-blue-yellow 3-stack hybrid WOLED structure is reported. In addition, the blue-yellow-blue 3-stack architecture exhibits an improved angular dependence compared to the blue-blue-yellow structure at a decreased EQE of 19.1%.

Stacking Fault Enriching the Electronic and Transport Properties of Few-Layer Phosphorenes and Black Phosphorus.

PubMed

Lei, Shuangying; Wang, Han; Huang, Lan; Sun, Yi-Yang; Zhang, Shengbai

2016-02-10

Interface engineering is critical for enriching the electronic and transport properties of two-dimensional materials. Here, we identify a new stacking, named Aδ, in few-layer phosphorenes (FLPs) and black phosphorus (BP) based on first-principles calculation. With its low formation energy, the Aδ stacking could exist in FLPs and BP as a stacking fault. The presence of the Aδ stacking fault induces a direct to indirect transition of the band gap in FLPs. It also affects the carrier mobilities by significantly increasing the carrier effective masses. More importantly, the Aδ stacking enables the fabrication of a whole spectrum of lateral junctions with all the type-I, II, and III alignments simply through the manipulation of the van der Waals stacking without resorting to any chemical modification. This is achieved by the widely tunable electron affinity and ionization potential of FLPs and BP with the Aδ stacking.

Preliminary study on rotary ultrasonic machining of CFRP/Ti stacks.

PubMed

Cong, W L; Pei, Z J; Treadwell, C

2014-08-01

Reported drilling methods for CFRP/Ti stacks include twist drilling, end milling, core grinding, and their derived methods. The literature does not have any report on drilling of CFRP/Ti stacks using rotary ultrasonic machining (RUM). This paper, for the first time, reports a study on drilling of CFRP/Ti stacks using RUM. It also compares results on drilling of CFRP/Ti stacks using RUM with reported results on drilling of CFRP/Ti stacks using other methods. When drilling CFRP/Ti stacks using RUM, cutting force, torque, and CFRP surface roughness were lower, hole size variation was smaller, CFRP groove depth was smaller, tool life was longer, and there was no obvious Ti exit burr and CFRP entrance delamination. Ti surface roughness when drilling of CFRP/Ti stacks using RUM was about the same as those when using other methods. Copyright © 2014 Elsevier B.V. All rights reserved.

Stacking-dependent electronic property of trilayer graphene epitaxially grown on Ru(0001)

NASA Astrophysics Data System (ADS)

Que, Yande; Xiao, Wende; Chen, Hui; Wang, Dongfei; Du, Shixuan; Gao, Hong-Jun

2015-12-01

The growth, atomic structure, and electronic property of trilayer graphene (TLG) on Ru(0001) were studied by low temperature scanning tunneling microscopy and spectroscopy in combined with tight-binding approximation (TBA) calculations. TLG on Ru(0001) shows a flat surface with a hexagonal lattice due to the screening effect of the bottom two layers and the AB-stacking in the top two layers. The coexistence of AA- and AB-stacking in the bottom two layers leads to three different stacking orders of TLG, namely, ABA-, ABC-, and ABB-stacking. STS measurements combined with TBA calculations reveal that the density of states of TLG with ABC- and ABB-stacking is characterized by one and two sharp peaks near to the Fermi level, respectively, in contrast to the V-shaped feature of TLG with ABA-stacking. Our work demonstrates that TLG on Ru(0001) might be an ideal platform for exploring stacking-dependent electronic properties of graphene.

Horizontal high speed stacking for batteries with prismatic cans

DOEpatents

Bartos, Andrew L.; Lin, Yhu-Tin; Turner, III, Raymond D.

2016-06-14

A system and method for stacking battery cells or related assembled components. Generally planar, rectangular (prismatic-shaped) battery cells are moved from an as-received generally vertical stacking orientation to a generally horizontal stacking orientation without the need for robotic pick-and-place equipment. The system includes numerous conveyor belts that work in cooperation with one another to deliver, rotate and stack the cells or their affiliated assemblies. The belts are outfitted with components to facilitate the cell transport and rotation. The coordinated movement between the belts and the components promote the orderly transport and rotation of the cells from a substantially vertical stacking orientation into a substantially horizontal stacking orientation. The approach of the present invention helps keep the stacked assemblies stable so that subsequent assembly steps--such as compressing the cells or attaching electrical leads or thermal management components--may proceed with a reduced chance of error.

Effect of product form, compaction, vibration and comminution on energywood bulk density

Treesearch

Tim P. McDonald; Bryce J. Stokes; J.F. McNeel

1995-01-01

A study was performed to examine the changes in density of stacked roundwood, chips, and chunks as affected by various compaction treatments. Density of stacked roundwood bolts was tested for the effect of stacking orientation, binding of the stack ends, and species. Stacked bolt wood occupied less than 50 percent of the total rack space for all species, giving final...

The Role of Standards in Cloud-Computing Interoperability

DTIC Science & Technology

2012-10-01

services are not shared outside the organization. CloudStack, Eucalyptus, HP, Microsoft, OpenStack , Ubuntu, and VMWare provide tools for building...center requirements • Developing usage models for cloud ven- dors • Independent IT consortium OpenStack http://www.openstack.org • Open-source...software for running private clouds • Currently consists of three core software projects: OpenStack Compute (Nova), OpenStack Object Storage (Swift

Overpressure Prediction From Seismic Data: Implications on Drilling Safety

NASA Astrophysics Data System (ADS)

Osinowo, O. O.; Oladunjoye, M. A.; Olayinka, A. I.

2007-12-01

High rate of sediment influx into the Niger Delta via river Niger coupled with high rate of basin subsidence, very thick clayey members of Agbada and Akata Formations as well as prevailing presence of growth faults had been identified as the main factors responsible for overpressure generation and preservation in the Niger Delta basin. Analysis of porosity dependent parameters such as interval transit times and interval velocities derived from the seismic records of a field in the Western Niger Delta revealed the presence of overpressured formation at depth of 8670 feet, which is the top of the overpressured zone. The plot of interval transit times against depth gave a positive deflection from normal at the region of overpressure while interval velocity plot gave negative deflection; the ratio of this deviation in both cases is as high as 1.52. Pressure gradient in the upper, normally pressured part of the field was determined to be 0.465 psi/ft., which is within the established normal pressure gradient range in Niger Delta, while the abnormal formation pressure gradient in the overpressured region was determined to be 0.96 psi/ft., and this is also within the published abnormal pressure gradient range of 0.71 to 1.1 psi/ft. in Niger Delta. Formation fracture pressure gradients were determined from the formation pressure information to be 0.66psi/ft. in the upper part of the field and 1.2psi/ft. in the overpressured horizon. Mud weight window (MWW); mud density range necessary to prevent formation kick without initiating hydraulic fracturing was determined to be 10.2 to 12.5lbm/gal in the upper part of the field and 22.1 to 22.63lbm/gal in the overpressured horizon. MWW is indispensable for the selection of the mud pump type, capacity, pumping rate and mud densities at different formation pressure regimes. Overpressure prediction is also requisite for drilling program design, casing design as well as rig capacity choice before spudding. It is necessary to reduce well construction risk, save drilling hour as well as cut down drilling cost. If adequate predictions are not taken however, drilling hazards known as blowout may occur. Blowout, an uncontrollable flow of formation fluid into the well has made oil exploration and exploitation activities in Niger Delta, Southern Nigeria, a curse for the people rather than a blessing because considerable numbers of wells blew out during well construction activities, hence the characteristic oil spill which had degraded the environment, making fishing operation, a source of livelihood of the people difficult. Therefore the need for overpressure prediction as a guide for safe drilling, especially in unfamiliar exploration environments.

Develop and test fuel cell powered on site integrated total energy sysems: Phase 3: Full-scale power plant development

NASA Technical Reports Server (NTRS)

Kaufman, A.; Olson, B.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

1986-01-01

A 25-cell stack of the 13 inch x 23 inch cell size (about 4kW) remains on test after 8300 hours, using simulated reformate fuel. A similar stack was previously shut down after 7000 hours on load. These tests have been carried out for the purpose of assessing the durability of fuel cell stack components developed through the end of 1983. A 25kW stack containing 175 cells of the same size and utilizing a technology base representative of the 25-cell stacks has been constructed and is undergoing initial testing. A third 4kW stack is being prepared, and this stack will incorporate several new technology features.

Design and assembly considerations for Redox cells and stacks

NASA Technical Reports Server (NTRS)

Stalnaker, D. K.; Lieberman, A.

1981-01-01

Individual redox flow cells are arranged electrically in series and hydraulically in parallel to form a single assembly called a stack. The hardware currently being tested in the laboratory has an active electrode area of either 310 sq cm or 929 sq cm. Four 310 sq cm stacks, each consisting of 39 active cells, were incorporated into a 1.0 kW preprototype system. The physical design of the stack is very critical to the performance and efficiency of the redox storage sytem. This report will discuss the mechanical aspects of the cell and stack design for the current Redox hardware, with regard to sealing the stack internally as well as externally, minimizing shunt currents and minimizing the electrical resistance of the stack.