Evaluation of Water-Chemistry and Water-Level Data at the Henderson Road Superfund Site, Upper Merion Township, Montgomery County, Pennsylvania, 1991-2008

USGS Publications Warehouse

Sloto, Ronald A.

2009-01-01

Several shutdown-rebound tests have been conducted at the Henderson Road Superfund Site, which has been on the U.S. Environmental Protection Agency's National Priorities List since 1984. For a given test, the extraction wells are turned off, and water samples are collected from selected monitor wells at regular intervals before and during cessation of pumping to monitor for changes in chemical concentrations. A long-term shutdown-rebound test began on July 17, 2006. In support of this test, the U.S. Geological Survey conducted this study to determine the effects of shutting down on-site extraction wells on concentrations of selected contaminants and water levels. Concentrations were compared to ARARs (applicable relevant and appropriate requirements), which were set as remediation goals in the Henderson Road Site Record of Decision. Water from 10 wells in and near the source area and to the north, northeast, and northwest of the source area sampled in 2008 exceeded the 5.52 ug/L (micrograms per liter) ARAR for benzene. The greatest changes in benzene concentration between pre-shutdown samples collected in July 2006 and samples collected in February and March 2008 (19 months after the shutdown) were for wells in and north of the source area; increases in benzene concentration ranged from 1.5 to 164 ug/L. Water from five wells in the source area and to the north and northwest of the source area sampled in 2008 exceeded the 60 ug/L ARAR for chlorobenzene. The greatest changes in chlorobenzene concentration between pre-shutdown samples collected in July 2006 and samples collected in February and March 2008 were for wells north of the source area; increases in chlorobenzene concentration ranged from 6.9 to 99 ug/L. The highest concentrations of chlorobenzene were near or outside the northern site boundary, indicating chlorobenzene may have moved north away from the source area; however, no monitor well clusters are on the northern side of the Pennsylvania Turnpike, which is about 190 feet north of the source area. A much larger area was affected by chlorobenzene than benzene. Chlorobenzene concentrations decreased in the source area and increased at and beyond the site boundary. Water from four wells in and northeast of the source area sampled in 2008 exceeded the 5.06 ug/L ARAR for 1,1-dichloroethane (1,1-DCA). Increases in 1,1-DCA concentration between pre-shutdown samples collected in July 2006 and samples collected in February 2008 ranged from 0.4 to 20 ug/L. Water from two wells in the source area sampled in 2008 exceeded the 175 ug/L ARAR for total xylene. The 1,1-DCA and xylene plumes appear to extend in an east-northeast direction from the source area. Large drawdowns in the Upper Merion Reservoir during droughts in 1998 and 2001 affected water levels in the Chester Valley and at the Henderson Road Site, except for well HR-17-170. After the drought of 2001, water levels in the Chester Valley showed a protracted recovery lasting from September 2001 until June 2005 (46 months). Water-level data were evaluated temporally for 1997-2008 and spatially for (1) June 16, 2003, when the extraction wells were pumping at the full rate prior to the start of the June 2003 shutdown test; (2) July 10, 2006, during the period of reduced pumping after the June 2003 shutdown test; and (3) February 25-29, 2008, when the extraction wells were not pumping. Except for well HR-5-195, wells were categorized as shallow, intermediate-depth, and deep wells. The potentiometric surface for shallow wells did not appear to be affected by pumping of the extraction wells. The general direction of ground-water flow was to the north. The potentiometric surface for intermediate-depth wells showed a cone of depression when the extraction wells were pumping at the full rate but did not show a cone of depression when the extraction wells were pumping at the reduced rate. The ground-water-flow direction was toward the north and northeast, similar to

Advanced radiator concepts feasibility demonstration

NASA Astrophysics Data System (ADS)

Rhee, Hyop S.; Begg, Lester; Wetch, Joseph R.; Juhasz, Albert J.

1991-01-01

An innovative pumped loop concept for 600 K space power system radiators is under development utilizing direct contact heat transfer, which facilitates repeated startup/shutdown of the power system without complex and time-consuming coolant thawing during power startup. The melting/freezing process of Li in a NaK flow was studied experimentally to demonstrate the Li/NaK radiator feasibility during startup (thawing) and shutdown (cold-trapping). Results of the vapor grown carbon fiber/composite thermal conductivity measurements are also presented.

Advanced radiator concepts feasibility demonstration

NASA Astrophysics Data System (ADS)

Rhee, Hyop S.; Begg, Lester; Wetch, Joseph R.; Juhasz, Albert J.

An innovative pumped loop concept for 600 K space power system radiators is under development utilizing direct contact heat transfer, which facilitates repeated startup/shutdown of the power system without complex and time-consuming coolant thawing during power startup. The melting/freezing process of Li in a NaK flow was studied experimentally to demonstrate the Li/NaK radiator feasibility during startup (thawing) and shutdown (cold-trapping). Results of the vapor grown carbon fiber/composite thermal conductivity measurements are also presented.

Self-actuated nuclear reactor shutdown system using induction pump to facilitate sensing of core coolant temperature

DOEpatents

Sievers, Robert K.; Cooper, Martin H.; Tupper, Robert B.

1987-01-01

A self-actuated shutdown system incorporated into a reactivity control assembly in a nuclear reactor includes pumping means for creating an auxiliary downward flow of a portion of the heated coolant exiting from the fuel assemblies disposed adjacent to the control assembly. The shutdown system includes a hollow tubular member which extends through the outlet of the control assembly top nozzle so as to define an outer annular flow channel through the top nozzle outlet separate from an inner flow channel for primary coolant flow through the control assembly. Also, a latching mechanism is disposed in an inner duct of the control assembly and is operable for holding absorber bundles in a raised position in the control assembly and for releasing them to drop them into the core of the reactor for shutdown purposes. The latching mechanism has an inner flow passage extending between and in flow communication with the absorber bundles and the inner flow channel of the top nozzle for accommodating primary coolant flow upwardly through the control assembly. Also, an outer flow passage separate from the inner flow passage extends through the latching mechanism between and in flow communication with the inner duct and the outer flow channel of the top nozzle for accommodating inflow of a portion of the heated coolant from the adjacent fuel assemblies. The latching mechanism contains a magnetic material sensitive to temperature and operable to cause mating or latching together of the components of the latching mechanism when the temperature sensed is below a known temperature and unmating or unlatching thereof when the temperature sensed is above a given temperature. The temperature sensitive magnetic material is positioned in communication with the heated coolant flow through the outer flow passage for directly sensing the temperature thereof. Finally, the pumping means includes a jet induction pump nozzle and diffuser disposed adjacent the bottom nozzle of the control assembly and in flow communication with the inlet thereof. The pump nozzle is operable to create an upward driving flow of primary coolant through the pump diffuser and then to the absorber bundles. The upward driving flow of primary coolant, in turn, creates a suction head within the outer flow channel of the top nozzle and thereby an auxiliary downward flow of the heated coolant portion exiting from the upper end of the adjacent fuel assemblies through the outer flow channel to the pump nozzle via the outer flow passage of the latching mechanism and an annular space between the outer and inner spaced ducts of the control assembly housing. The temperature of the heated coolant exiting from the adjacent fuel assemblies can thereby be sensed directly by the temperature sensitive magnetic material in the latching mechanism.

A Guide for Developing Standard Operating Job Procedures for the Pump Station Process Wastewater Treatment Facility. SOJP No. 3.

ERIC Educational Resources Information Center

Perley, Gordon F.

This is a guide for standard operating job procedures for the pump station process of wastewater treatment plants. Step-by-step instructions are given for pre-start up inspection, start-up procedures, continuous routine operation procedures, and shut-down procedures. A general description of the equipment used in the process is given. Two…

End-pumped 300 W continuous-wave ytterbium-doped all-fiber laser with master oscillator multi-stage power amplifiers configuration.

PubMed

Yin, Shupeng; Yan, Ping; Gong, Mali

2008-10-27

An end-pumped ytterbium-doped all-fiber laser with 300 W output in continuous regime was reported, which was based on master oscillator multi-stage power amplifiers configuration. Monolithic fiber laser system consisted of an oscillator stage and two amplifier stages. Total optical-optical efficiency of monolithic fiber laser was approximately 65%, corresponding to 462 W of pump power coupled into laser system. We proposed a new method to connect power amplifier stage, which was crucial for the application of end-pumped combiner in high power MOPAs all-fiber laser.

46 CFR 154.1842 - Cargo system: Controls and alarms.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Cargo system: Controls and alarms. 154.1842 Section 154... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1842 Cargo system: Controls and alarms. The master shall ensure that the cargo emergency shut-down system and the...

46 CFR 154.1842 - Cargo system: Controls and alarms.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo system: Controls and alarms. 154.1842 Section 154... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1842 Cargo system: Controls and alarms. The master shall ensure that the cargo emergency shut-down system and the...

Proton-pumping mechanism of cytochrome c oxidase: A kinetic master-equation approach

PubMed Central

Kim, Young C.; Hummer, Gerhard

2011-01-01

Cytochrome c oxidase (CcO) is an efficient energy transducer that reduces oxygen to water and converts the released chemical energy into an electrochemical membrane potential. As a true proton pump, CcO translocates protons across the membrane against this potential. Based on a wealth of experiments and calculations, an increasingly detailed picture of the reaction intermediates in the redox cycle has emerged. However, the fundamental mechanism of proton pumping coupled to redox chemistry remains largely unresolved. Here we examine and extend a kinetic master-equation approach to gain insight into redox-coupled proton pumping in CcO. Basic principles of the CcO proton pump emerge from an analysis of the simplest kinetic models that retain essential elements of the experimentally determined structure, energetics, and kinetics, and that satisfy fundamental physical principles. The master-equation models allow us to address the question of how pumping can be achieved in a system in which all reaction steps are reversible. Whereas proton pumping does not require the direct modulation of microscopic reaction barriers, such kinetic gating greatly increases the pumping efficiency. Further efficiency gains can be achieved by partially decoupling the proton uptake pathway from the ative-site region. Such a mechanism is consistent with the proposed Glu valve, in which the side chain of a key glutamic acid shuttles between the D channel and the active-site region. We also show that the models predict only small proton leaks even in the absence of turnover. The design principles identified here for CcO provide a blueprint for novel biology-inspired fuel cells, and the master-equation formulation should prove useful also for other molecular machines. PMID:21946020

Study of a heat rejection system using capillary pumping

NASA Technical Reports Server (NTRS)

Neal, L. G.; Wanous, D. J.; Clausen, O. W.

1971-01-01

Results of an analytical study investigating the application of capillary pumping to the heat rejection loop of an advanced Rankine cycle power conversion system are presented. The feasibility of the concept of capillary pumping as an alternate to electromagnetic pumping is analytically demonstrated. Capillary pumping is shown to provide a potential for weight and electrical power saving and reliability through the use of redundant systems. A screen wick pump design with arterial feed lines was analytically developed. Advantages of this design are high thermodynamic and hydrodynamic efficiency, which provide a lightweight easily packaged system. Operational problems were identified which must be solved for successful application of capillary pumping. The most important are the development of start up and shutdown procedures, and development of a means of keeping noncondensibles from the system and of earth-bound testing procedures.

Effect of reduced industrial pumpage on the migration of dissolved nitrogen in an outwash aquifer at Olean, Cattaraugus County, New York

USGS Publications Warehouse

Bergeron, M.P.

1987-01-01

A quasi-three-dimensional digital groundwater flow model of a shallow outwash aquifer system at Olean, New York, was developed to study the effects of several pumping alternatives on groundwater flow and stream seepage. Nitrogen compounds have contaminated the aquifer in an industrial park in North Olean. Pumping from seven industrial production wells and a purge well has created a cone of depression within which all nitrogen compounds are contained, thus preventing their migration to nearby private, municipal, and industrial-supply wells. A simulated total shutdown of an industrial well field and the purge well indicates that groundwater flowing laterally southward to southwestward from the area of contamination would require about 5 yr to reach a municipal well field along the Allegheny River. Simulation of a partial shutdown with only three main production wells and the purge well or just the three production wells indicate that all nitrogen-bearing groundwater would be captured. Pumping from only the purge well would allow contaminated groundwater along the southwestern edge of the site to escape and, in 8 to 9 yr, reach the municipal well field. (USGS)

Bipropellant propulsion with reciprocating pumps

NASA Astrophysics Data System (ADS)

Whitehead, John C.

1993-06-01

A pressure regulated gas generator rocket cycle with alternately pressurized pairs of reciprocating pumps offers thrust-on-demand operation with significantly lower inert mass than conventional spacecraft liquid propulsion systems. The operation of bipropellant feed systems with reciprocating pumps is explained, with consideration for both short and long term missions. There are several methods for startup and shutdown of this self-starting pump-fed system, with preference determined by thrust duty cycle and mission duration. Progress to date includes extensive development testing of components unique to this type of system, and several live tests with monopropellant hydrazine. Pneumatic pump control valves which render pistons and bellows automatically responsive to downstream liquid demand are significantly simpler than those described previously. A compact pumpset mounted to central liquid manifolds has a pair of oxidizer pumps pneumatically slaved to a pair of fuel pumps to reduce vibration. A warm gas pressure reducer for tank expulsion can eliminate any remaining need for inert gas storage.

NASA Advanced Radiator Technology Development

NASA Astrophysics Data System (ADS)

Koester, J. Kent; Juhasz, Albert J.

1994-07-01

A practical implementation of the two-phase working fluid of lithium and NaK has been developed experimentally for pumped loop radiator designs. The benefits of the high heat capacity and low mass of lithium have been integrated with the shutdown capability enabled by the low freezing temperature of NaK by mixing these liquid metals directly. The stable and reliable start up and shutdown of a lithium/NaK pumped loop has been demonstrated through the development of a novel lithium freeze-separation technique within the flowing header ducts. The results of a highly instrumented liquid metal test loop are presented in which both lithium fraction as well as loop gravitational effects were varied over a wide range of values. Diagnostics based on dual electric probes are presented in which the convective behavior of the lithium component is directly measured during loop operation. The uniform distribution of the lithium after a freeze separation is verified by neutron radiography. The operating regime for reliable freeze/thaw flow behavior is described in terms of correlations based on dimensional analysis.

Hybrid solid state laser system using a neodymium-based master oscillator and an ytterbium-based power amplifier

DOEpatents

Payne, Stephen A.; Marshall, Christopher D.; Powell, Howard T.; Krupke, William F.

2001-01-01

In a master oscillator-power amplifier (MOPA) hybrid laser system, the master oscillator (MO) utilizes a Nd.sup.3+ -doped gain medium and the power amplifier (PA) utilizes a diode-pumped Yb.sup.3+ -doped material. The use of two different laser gain media in the hybrid MOPA system provides advantages that are otherwise not available. The Nd-doped gain medium preferably serves as the MO because such gain media offer the lowest threshold of operation and have already been engineered as practical systems. The Yb-doped gain medium preferably serves in the diode-pumped PA to store pump energy effectively and efficiently by virtue of the long emission lifetime, thereby reducing diode pump costs. One crucial constraint on the MO and PA gain media is that the Nd and Yb lasers must operate at nearly the same wavelength. The 1.047 .mu.m Nd:YLF/Yb:S-FAP [Nd:LiYF.sub.4 /Yb:Sr.sub.5 (PO.sub.4).sub.3 F] hybrid MOPA system is a preferred embodiment of the hybrid Nd/Yb MOPA.

46 CFR 109.329 - Fire pumps.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire pumps. 109.329 Section 109.329 Shipping COAST GUARD... of Safety Equipment § 109.329 Fire pumps. The master or person in charge shall insure that at least one of the fire pumps required in § 108.415 is ready for use on the fire main system at all times. ...

76 FR 33660 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-09

...We propose to supersede an existing airworthiness directive (AD) that applies to the products listed above. The existing AD currently requires frequent inspections of the fuel pressure supply for excessive oscillations to determine if high-pressure fuel pumps have been exposed to damaging pressure oscillations. Pumps that have been exposed require replacement before further flight. Since we issued that AD, Austro Engine, the manufacturer of the pump, introduced a new part number (P/N) fuel pump as mandatory terminating action to the repetitive inspections. This proposed AD would require the initial and repetitive inspections of AD 2010-23-09, but would also require installing HP fuel pump P/N E4A-30-200-000, as mandatory terminating action to the repetitive inspections. We are proposing this AD to prevent engine power loss or in-flight shutdown, which could result in loss of control of the airplane.

A large high vacuum, high pumping speed space simulation chamber for electric propulsion

NASA Technical Reports Server (NTRS)

Grisnik, Stanley P.; Parkes, James E.

1994-01-01

Testing high power electric propulsion devices poses unique requirements on space simulation facilities. Very high pumping speeds are required to maintain high vacuum levels while handling large volumes of exhaust products. These pumping speeds are significantly higher than those available in most existing vacuum facilities. There is also a requirement for relatively large vacuum chamber dimensions to minimize facility wall/thruster plume interactions and to accommodate far field plume diagnostic measurements. A 4.57 m (15 ft) diameter by 19.2 m (63 ft) long vacuum chamber at NASA Lewis Research Center is described. The chamber utilizes oil diffusion pumps in combination with cryopanels to achieve high vacuum pumping speeds at high vacuum levels. The facility is computer controlled for all phases of operation from start-up, through testing, to shutdown. The computer control system increases the utilization of the facility and reduces the manpower requirements needed for facility operations.

77 FR 61303 - Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-09

...-mechanical metering unit (HMU). This proposed AD would require replacing the HMU at a reduced life. We are... pressure/low pressure (HP/LP) pump assembly within the hydro- mechanical metering unit (HMU), removed...-mechanical metering unit (HMU). We are issuing this AD to prevent an uncommanded in-flight shutdown of the...

78 FR 9001 - Airworthiness Directives; Hamilton Sundstrand Corporation Propellers

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-07

... Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your...) of auxiliary feathering pumps from service. We are proposing this AD to prevent propellers from failing to move into the feathering position after an engine in-flight shutdown. Propellers failing to...

Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion

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

Baek J.; Diamond D.; Cuadra, A.

Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a modelmore » of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.« less

Pump Diode Characterization for an Unstable Diode-Pumped Alkali Laser Resonator

DTIC Science & Technology

2013-03-01

2003. Petersen, A., and R. Lane, Second harmonic operation of diode-pumped Rb vapor lasers , Proc. of SPIE, 7005, 2008. Siegman , A. E., Lasers ...University Science Books, Sausalito, CA, 1986. Siegman , A. E., Defining, measuring and optimizing laser beam quality, Proc. of SPIE, 1868, 1993. Steck, D...PUMP DIODE CHARACTERIZATION FOR AN UNSTABLE DIODE-PUMPED ALKALI LASER RESONATOR THESIS Chad T. Taguba, Master Sergeant, USAF AFIT-ENP-13-M-33

Hydraulic Actuator for Ganged Control Rods

NASA Technical Reports Server (NTRS)

Thompson, D. C.; Robey, R. M.

1986-01-01

Hydraulic actuator moves several nuclear-reactor control rods in unison. Electromagnetic pump pushes liquid lithium against ends of control rods, forcing them out of or into nuclear reactor. Color arrows show lithium flow for reactor startup and operation. Flow reversed for shutdown. Conceived for use aboard spacecraft, actuator principle applied to terrestrial hydraulic machinery involving motion of ganged rods.

76 FR 54373 - Airworthiness Directives; Austro Engine GmbH Model E4 Diesel Piston Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-01

...We are superseding an existing airworthiness directive (AD) for the products listed above. That AD currently requires frequent inspections of the fuel pressure supply for excessive oscillations to determine if high-pressure (HP) fuel pumps have been exposed to damaging pressure oscillations. Pumps that have been exposed require replacement before further flight. This new AD requires the initial and repetitive inspections of AD 2010-23-09, but also requires installing HP fuel pump part number (P/N) E4A-30-200-000, as mandatory terminating action to the repetitive inspections. We are issuing this AD to prevent engine power loss or in-flight shutdown, which could result in loss of control of the airplane.

Performance evaluation of SPE electrolyzer for Space Station life support

NASA Technical Reports Server (NTRS)

Erickson, A. C.; Puskar, M. C.; Zagaja, J. A.; Miller, P. S.

1987-01-01

An static water-vapor feed electrolyzer has been developed as a candidate for Space Station life-support oxygen generation. The five-cell electrolysis module has eliminated the need for phase separation devices, pumps, and deionizers by transporting only water vapor to the solid polymer electrolyte cells. The introduction of an innovative electrochemical hydrogen pump allows the use of low-pressure reclaimed water to generate gas pressures of up to 230 psia. The electrolyzer has been tested in a computer-controlled test stand featuring continuous, cyclic, and standby operation (including automatic shutdown with fault detection).

@Astro_Wheels Tweetup

NASA Image and Video Library

2011-03-16

Astronaut Doug Wheelock discusses his experiences while living on the International Space Station during a tweetup at NASA Headquarters in Washington, Wednesday, March 16, 2011. Wheelock, who has accumulated a total of 178 days in space, assumed command of the International Space Station and the Expedition 25 crew. During Expedition 25, there were more than 120 microgravity experiments in human research; biology and biotechnology; physical and materials sciences; technology development; and Earth and space sciences. Wheelock also responded to an emergency shutdown of half of the station's external cooling system and supported three unplanned spacewalks to replace the faulty pump module that caused the shutdown. His efforts restored the station's critical cooling system to full function. The mission duration was 163 days. Photo Credit: (NASA/Paul E. Alers)

Compact, passively Q-switched, all-solid-state master oscillator-power amplifier-optical parametric oscillator (MOPA-OPO) system pumped by a fiber-coupled diode laser generating high-brightness, tunable, ultraviolet radiation.

PubMed

Peuser, Peter; Platz, Willi; Fix, Andreas; Ehret, Gerhard; Meister, Alexander; Haag, Matthias; Zolichowski, Paul

2009-07-01

We report on a compact, tunable ultraviolet laser system that consists of an optical parametric oscillator (OPO) and a longitudinally diode-pumped Nd:YAG master oscillator-power amplifier (MOPA). The pump energy for the whole laser system is supplied via a single delivery fiber. Nanosecond pulses are produced by an oscillator that is passively Q-switched by a Cr(4+):YAG crystal. The OPO is pumped by the second harmonic of the Nd:YAG MOPA. Continuously tunable radiation is generated by an intracavity sum-frequency mixing process within the OPO in the range of 245-260 nm with high beam quality. Maximum pulse energies of 1.2 mJ were achieved, which correspond to an optical efficiency of 3.75%, relating to the pulse energy of the MOPA at 1064 nm.

77 FR 51462 - Airworthiness Directives; BRP-Powertrain GmbH & Co KG Rotax Reciprocating Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-24

... landing and damage to the airplane. DATES: This AD becomes effective September 10, 2012. We must receive... carburetor, which could result in an in-flight engine shutdown, forced landing and damage to the airplane. (e... pump with an S/N listed in Table 1 to paragraph (c) of this AD in any airplane unless it has been...

Hotfire testing of a SSME HPOTP with an annular hydrostatic bearing

NASA Technical Reports Server (NTRS)

Nolan, Steven A.; Hibbs, Robert I.; Genge, Gary G.

1993-01-01

A new fluid film bearing package has been tested in the SSME High Pressure Oxygen Turbopump (HPOTP). This fluid film element functions as both the pump end bearing and the preburner pump rear wear ring seal. Most important, it replaces a duplex ball bearing package which has been the primary life limiting component in the turbopump. The design and predicted performance of the turbopump are reviewed. Results are presented for measured pump and bearing performance. The most significant results were obtained from proximity probes located in the bearing bore which revealed large subsynchronous precession at 10 percent of shaft speed during engine start which subsided prior to mainstage power levels and reappeared during engine shutdown at equivalent power levels below 65 percent of nominal. This phenomenon has been attributed to rotating stall in the diffuser. The proximity probes also revealed the location of the bearing in the bore for different operating speeds. Pump vibration characteristics were improved as compared to pumps tested with ball bearings. After seven starts and more than 700 seconds of testing, the pump showed no signs of performance degradation.

@Astro_Wheels Tweetup

NASA Image and Video Library

2011-03-16

A tweetuup participant videotapes with her iPhone and tweets as astronaut Doug Wheelock discusses his experiences while living on the International Space Station during a tweetup at NASA Headquarters in Washington, Wednesday, March 16, 2011. Wheelock, who has accumulated a total of 178 days in space, assumed command of the International Space Station and the Expedition 25 crew. During Expedition 25, there were more than 120 microgravity experiments in human research; biology and biotechnology; physical and materials sciences; technology development; and Earth and space sciences. Wheelock also responded to an emergency shutdown of half of the station's external cooling system and supported three unplanned spacewalks to replace the faulty pump module that caused the shutdown. His efforts restored the station's critical cooling system to full function. The mission duration was 163 days. Photo Credit: (NASA/Paul E. Alers)

High peak-power mid-infrared ZnGeP₂ optical parametric oscillator pumped by a Tm:fiber master oscillator power amplifier system.

PubMed

Gebhardt, Martin; Gaida, Christian; Kadwani, Pankaj; Sincore, Alex; Gehlich, Nils; Jeon, Cheonha; Shah, Lawrence; Richardson, Martin

2014-03-01

We report on the utilization of a novel Tm:fiber laser source for mid-IR ZnGeP2 (ZGP) optical parametric oscillator (OPO) pumping. The pump laser is built in a master oscillator power-amplifier configuration delivering up to 3.36 W of polarized, diffraction limited output power with 7 ns pulse duration and 4 kHz repetition rate. This corresponds to a peak power of ∼121  kW and a pulse energy of ∼0.84  mJ. With this source, we generated 27.9 kW of total mid-IR peak power in a doubly resonant oscillator (DRO) configuration. This is, to the best of our knowledge, the highest ever demonstrated mid-IR peak power from a directly Tm:fiber laser pumped ZGP OPO. Moreover, a DRO output with about 284 μJ of total mid-IR pulse energy was demonstrated using 100 ns pump pulses. The wavelength tuning of the idler was extended to 6 μm with lower output power in another OPO experiment.

Explosive electromagnetic radiation by the relaxation of a multimode magnon system.

PubMed

Vasyuchka, V I; Serga, A A; Sandweg, C W; Slobodianiuk, D V; Melkov, G A; Hillebrands, B

2013-11-01

Microwave emission from a parametrically pumped ferrimagnetic film of yttrium iron garnet was studied versus the magnon density evolution, which was detected by Brillouin light scattering spectroscopy. It has been found that the shutdown of external microwave pumping leads to an unexpected effect: The conventional monotonic decrease of the population of parametrically injected magnons is accompanied by an explosive behavior of electromagnetic radiation at the magnon frequency. The developed theory shows that this explosion is caused by a nonlinear energy transfer from parametrically driven short-wavelength dipolar-exchange magnons to a long-wavelength dipolar magnon mode effectively coupled to an electromagnetic wave.

Experimental investigation of a new method for advanced fast reactor shutdown cooling

NASA Astrophysics Data System (ADS)

Pakholkov, V. V.; Kandaurov, A. A.; Potseluev, A. I.; Rogozhkin, S. A.; Sergeev, D. A.; Troitskaya, Yu. I.; Shepelev, S. F.

2017-07-01

We consider a new method for fast reactor shutdown cooling using a decay heat removal system (DHRS) with a check valve. In this method, a coolant from the decay heat exchanger (DHX) immersed into the reactor upper plenum is supplied to the high-pressure plenum and, then, inside the fuel subassemblies (SAs). A check valve installed at the DHX outlet opens by the force of gravity after primary pumps (PP-1) are shut down. Experimental studies of the new and alternative methods of shutdown cooling were performed at the TISEY test facility at OKBM. The velocity fields in the upper plenum of the reactor model were obtained using the optical particle image velocimetry developed at the Institute of Applied Physics (Russian Academy of Sciences). The study considers the process of development of natural circulation in the reactor and the DHRS models and the corresponding evolution of the temperature and velocity fields. A considerable influence of the valve position in the displacer of the primary pump on the natural circulation of water in the reactor through the DHX was discovered (in some modes, circulation reversal through the DHX was obtained). Alternative DHRS designs without a shell at the DHX outlet with open and closed check valve are also studied. For an open check valve, in spite of the absence of a shell, part of the flow is supplied through the DHX pipeline and then inside the SA simulators. When simulating power modes of the reactor operation, temperature stratification of the liquid was observed, which increased in the cooling mode via the DHRS. These data qualitatively agree with the results of tests at BN-600 and BN-800 reactors.

Retrofitting a water-pumping station with adjustable speed drives: Feasibility analysis: Final report

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

Not Available

1988-08-01

The objective of this report is to develop a generalized methodology for examining water distribution systems for adjustable speed drive (ASD) applications and to provide an example (the City of Chicago 68th Street Water Pumping Station) using the methodology. The City of Chicago water system was chosen as the candidate for analysis because it has a large service area distribution network with no storage provisions after the distribution pumps. Many industrial motors operate at only one speed or a few speeds. By speeding up or slowing down, ASDs achieve gentle startups and gradual shutdowns thereby providing plant equipment a longermore » life with fewer breakdowns while minimizing the energy requirements. The test program substantiated that ASDs enhance product quality and increase productivity in many industrial operations, including extended equipment life. 35 figs.« less

Geothermal production and reduced seismicity: Correlation and proposed mechanism

NASA Astrophysics Data System (ADS)

Cardiff, Michael; Lim, David D.; Patterson, Jeremy R.; Akerley, John; Spielman, Paul; Lopeman, Janice; Walsh, Patrick; Singh, Ankit; Foxall, William; Wang, Herbert F.; Lord, Neal E.; Thurber, Clifford H.; Fratta, Dante; Mellors, Robert J.; Davatzes, Nicholas C.; Feigl, Kurt L.

2018-01-01

At Brady Hot Springs, a geothermal field in Nevada, heated fluids have been extracted, cooled, and re-injected to produce electrical power since 1992. Analysis of daily pumping records and catalogs of microseismicity between 2010 and 2015 indicates a statistically significant correlation between days when the daily volume of production was at or above its long-term average rate and days when no seismic event was detected. Conversely, shutdowns in pumping for plant maintenance correlate with increased microseismicity. We hypothesize that the effective stress in the subsurface has adapted to the long-term normal operations (deep extraction) at the site. Under this hypothesis, extraction of fluids inhibits fault slip by increasing the effective stress on faults; in contrast, brief pumping cessations represent times when effective stress is decreased below its long-term average, increasing the likelihood of microseismicity.

Generation of squeezed microwave states by a dc-pumped degenerate parametric Josephson junction oscillator

NASA Astrophysics Data System (ADS)

Kaertner, Franz X.; Russer, Peter

1990-11-01

The master equation for a dc-pumped degenerate Josephson parametric amplifier is derived. It is shown that the Wigner distribution representation of this master equation can be approximated by a Fokker-Planck equation. By using this equation, the dynamical behavior of this degenerate Josephson amplifier with respect to squeezing of the radiation field is investigated. It is shown that below threshold of parametric oscillation, a squeezed vacuum state can be generated, and above threshold a second bifurcation point exists, where the device generates amplitude squeezed radiation. Basic relations between the achievable amplitude squeezing, the output power, and the operation frequency are derived.

Single frequency 1083nm ytterbium doped fiber master oscillator power amplifier laser.

PubMed

Huang, Shenghong; Qin, Guanshi; Shirakawa, Akira; Musha, Mitsuru; Ueda, Ken-Ichi

2005-09-05

Single frequency 1083nm ytterbium fiber master oscillator power amplifier system was demonstrated. The oscillator was a linear fiber cavity with loop mirror filter and polarization controller. The loop mirror with unpumped ytterbium fiber as a narrow bandwidth filter discriminated and selected laser longitudinal modes efficiently. Spatial hole burning effect was restrained by adjusting polarization controller appropriately in the linear cavity. The amplifier was 5 m ytterbium doped fiber pumped by 976nm pigtail coupled laser diode. The linewidth of the single frequency laser was about 2 KHz. Output power up to 177 mW was produced under the launched pump power of 332 mW.

High Energy 2-Micron Laser Developments

NASA Technical Reports Server (NTRS)

Yu, Jirong; Trieu, Bo C.; Petros, Mulugeta; Bai, Yingxin; Petzar, Paul J.; Koch, Grady J.; Singh, Upendra N.; Kavaya, Michael J.

2007-01-01

A master oscillator power amplifier, high energy Q-switched 2-micron laser system has been recently demonstrated. The laser and amplifiers are all designed in side-pumped rod configuration, pumped by back-cooled conductive packaged GaAlAs diode laser arrays. This 2-micron laser system provides nearly transform limited beam quality.

Direct solar-pumped iodine laser amplifier

NASA Technical Reports Server (NTRS)

Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

1989-01-01

This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

Hotfire testing of a SSME HPOTP with an annular hydrostatic bearing

NASA Technical Reports Server (NTRS)

Nolan, Steven A.; Hibbs, Robert I.; Genge, Gary G.

1994-01-01

A new fluid film bearing package has been tested in the Space Shuttle Main Engine (SSME) High Pressure Oxygen Turbopump (HPOTP). This fluid film element functions as both the pump end bearing and the preburner pump rear wear ring seal. Most importantly, it replaces a duplex ball bearing package which has been the primary life limiting component in the turbopump. The design and predicted performance of the turbopump are reviewed. Results are presented for measured pump and bearing performance during testing on the NASA Technology Test Bed (TTB) Engine located at MSFC. The most significant results were obtained from proximity probes located in the bearing bore which revealed large subsynchronous precession at ten percent of shaft speed during engine start which subsided prior to mainstage power levels and reappeared during engine shutdown at equivalent power levels below 65% of nominal. This phenomenon has been attributed to rotating stall in the diffuser. The proximity probes also revealed the location of the bearing in the bore for different operating speeds. Pump vibration characteristics were improved as compared to pumps tested with ball bearings. After seven starts and more than 700 seconds of testing, the pump showed no signs of performance degradation.

1047 nm laser diode master oscillator Nd:YLF power amplifier laser system

NASA Technical Reports Server (NTRS)

Yu, A. W.; Krainak, M. A.; Unger, G. L.

1993-01-01

A master oscillator power amplifier (MOPA) laser transmitter system at 1047 nm wavelength using a semiconductor laser diode and a diode pumped solid state (Nd:YLF) laser (DPSSL) amplifier is described. A small signal gain of 23 dB, a near diffraction limited beam, 1 Gbit/s modulation rates and greater than 0.6 W average power are achieved. This MOPA laser has the advantage of amplifying the modulation signal from the laser diode master oscillator (MO) with no signal degradation.

885-nm laser diode array pumped ceramic Nd:YAG master oscillator power amplifier system

NASA Astrophysics Data System (ADS)

Yu, Anthony W.; Li, Steven X.; Stephen, Mark A.; Seas, Antonios; Troupaki, Elisavet; Vasilyev, Aleksey; Conley, Heather; Filemyr, Tim; Kirchner, Cynthia; Rosanova, Alberto

2010-04-01

The objective of this effort is to develop more reliable, higher efficiency diode pumped Nd:YAG laser systems for space applications by leveraging technology investments from the DoD and other commercial industries. Our goal is to design, build, test and demonstrate the effectiveness of combining 885 nm laser pump diodes and the use of ceramic Nd:YAG for future flight missions. The significant reduction in thermal loading on the gain medium by the use of 885 nm pump lasers will improve system efficiency.

Inherent Safety Characteristics of Advanced Fast Reactors

NASA Astrophysics Data System (ADS)

Bochkarev, A. S.; Korsun, A. S.; Kharitonov, V. S.; Alekseev, P. N.

2017-01-01

The study presents SFR transient performance for ULOF events initiated by pump trip and pump seizure with simultaneous failure of all shutdown systems in both cases. The most severe cases leading to the pin cladding rupture and possible sodium boiling are demonstrated. The impact of various features on SFR inherent safety performance for ULOF events was analysed. The decrease in hydraulic resistance of primary loop and increase in primary pump coast down time were investigated. Performing analysis resulted in a set of recommendations to varying parameters for the purpose of enhancing the inherent safety performance of SFR. In order to prevent the safety barrier rupture for ULOF events the set of thermal hydraulic criteria defining the ULOF transient processes dynamics and requirements to these criteria were recommended based on achieved results: primary sodium flow dip under the natural circulation asymptotic level and natural circulation rise time.

Geothermal production and reduced seismicity: Correlation and proposed mechanism

DOE PAGES

Cardiff, Michael; Lim, David D.; Patterson, Jeremy R.; ...

2018-01-15

At Brady Hot Springs, a geothermal field in Nevada, heated fluids have been extracted, cooled, and re-injected to produce electrical power since 1992. Analysis of daily pumping records and catalogs of microseismicity between 2010 and 2015 indicates a statistically significant correlation between days when the daily volume of production was at or above its long-term average rate and days when no seismic event was detected. Conversely, shutdowns in pumping for plant maintenance correlate with increased microseismicity. Our hypothesis is that the effective stress in the subsurface has adapted to the long-term normal operations (deep extraction) at the site. Under thismore » hypothesis, extraction of fluids inhibits fault slip by increasing the effective stress on faults; in contrast, brief pumping cessations represent times when effective stress is decreased below its long-term average, increasing the likelihood of microseismicity.« less

Geothermal production and reduced seismicity: Correlation and proposed mechanism

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

Cardiff, Michael; Lim, David D.; Patterson, Jeremy R.

At Brady Hot Springs, a geothermal field in Nevada, heated fluids have been extracted, cooled, and re-injected to produce electrical power since 1992. Analysis of daily pumping records and catalogs of microseismicity between 2010 and 2015 indicates a statistically significant correlation between days when the daily volume of production was at or above its long-term average rate and days when no seismic event was detected. Conversely, shutdowns in pumping for plant maintenance correlate with increased microseismicity. Our hypothesis is that the effective stress in the subsurface has adapted to the long-term normal operations (deep extraction) at the site. Under thismore » hypothesis, extraction of fluids inhibits fault slip by increasing the effective stress on faults; in contrast, brief pumping cessations represent times when effective stress is decreased below its long-term average, increasing the likelihood of microseismicity.« less

Compact millijoule diode-seeded two-stage fiber master oscillator power amplifier using a multipass and forward pumping scheme.

PubMed

Lai, Po-Yen; Chang, Chun-Lin; Huang, Sheng-Lung; Chen, Shih-Hung

2018-05-01

The multipass scheme for a diode-seeded fiber master oscillator power amplifier with a nanojoule-to-millijoule output energy level at a repetition rate of <100  kHz is numerically analyzed for comparison to an experimental benchmark. For a 6/125 single-mode preamplifier with a small input energy (<1  nJ), there is a significant improvement in the output energy from 0.7% to 80% and 95% of the maximum extractable energy using the double-pass and four-pass schemes, respectively. For a 30/250 large-mode-area power amplifier using the double-pass and forward pumping scheme, the required input energy is decreased from 100 μJ to 18 μJ for millijoule energy extraction with accompanying Stokes waves of less than 10% of the total energy. The system based on the full master oscillator power amplifier configuration with an output energy exceeding millijoule level can be optimally simplified to two stages for commercialization.

Vapor-Compression Heat Pumps for Operation Aboard Spacecraft

NASA Technical Reports Server (NTRS)

Ruemmele, Warren; Ungar, Eugene; Cornwell, John

2006-01-01

Vapor-compression heat pumps (including both refrigerators and heat pumps) of a proposed type would be capable of operating in microgravity and would be safe to use in enclosed environments like those of spacecraft. The designs of these pumps would incorporate modifications of, and additions to, vapor-compression cycles of heat pumps now used in normal Earth gravitation, in order to ensure efficiency and reliability during all phases of operation, including startup, shutdown, nominal continuous operation, and peak operation. Features of such a design might include any or all of the following: (1) Configuring the compressor, condenser, evaporator, valves, capillary tubes (if any), and controls to function in microgravitation; (2) Selection of a working fluid that satisfies thermodynamic requirements and is safe to use in a closed crew compartment; (3) Incorporation of a solenoid valve and/or a check valve to prevent influx of liquid to the compressor upon startup (such influx could damage the compressor); (4) Use of a diode heat pipe between the cold volume and the evaporator to limit the influx of liquid to the compressor upon startup; and (5) Use of a heated block to vaporize any liquid that arrives at the compressor inlet.

Biological proton pumping in an oscillating electric field.

PubMed

Kim, Young C; Furchtgott, Leon A; Hummer, Gerhard

2009-12-31

Time-dependent external perturbations provide powerful probes of the function of molecular machines. Here we study biological proton pumping in an oscillating electric field. The protein cytochrome c oxidase is the main energy transducer in aerobic life, converting chemical energy into an electric potential by pumping protons across a membrane. With the help of master-equation descriptions that recover the key thermodynamic and kinetic properties of this biological "fuel cell," we show that the proton pumping efficiency and the electronic currents in steady state depend significantly on the frequency and amplitude of the applied field, allowing us to distinguish between different microscopic mechanisms of the machine. A spectral analysis reveals dominant reaction steps consistent with an electron-gated pumping mechanism.

Effects of mobile phone use on specific intensive care unit devices.

PubMed

Hans, Nidhi; Kapadia, Farhad N

2008-10-01

To observe the effects of mobile phone use in the vicinity of medical devices used in a critical care setting. Electromagnetic interference (EMI) was tested by using two types of mobile phones - GSM and CDMA. Mobile phones were placed at a distance of one foot from three medical devices - syringe pump, mechanical ventilator, and the bedside monitor - in switch off, standby, and talking modes of the phone. Medical devices were observed for any interference caused by the electromagnetic radiations (EMR) from the mobile phones. Out of the three medical devices that were tested, EMI occurred while using the mobile phone in the vicinity of the syringe pump, in the 'talk mode.' The mean variation observed in the calculated and delivered volume of the syringe pump was 2.66 ml. Mechanical ventilator did not show any specific adverse effects with mobile phone use in the one-foot vicinity. No other adverse effects or unexplained malfunctions or shutdown of the syringe pump, mechanical ventilator, or the bedside monitor was noted during the study period of 36 hours. EMI from mobile phones have an adverse effect on the medical devices used in critical care setup. They should be used at least one foot away from the diameter of the syringe pump.

A pulse-burst laser system for a high-repetition-rate Thomson scattering diagnostic

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

Den Hartog, D. J.; Jiang, N.; Lempert, W. R.

2008-10-15

A ''pulse-burst'' laser system is being constructed for addition to the Thomson scattering diagnostic on the Madison Symmetric Torus (MST) reversed-field pinch. This laser is designed to produce a burst of up to 200 approximately 1 J Q-switched pulses at repetition frequencies 5-250 kHz. This laser system will operate at 1064 nm and is a master oscillator, power amplifier. The master oscillator is a compact diode-pumped Nd:YVO{sub 4} laser, intermediate amplifier stages are flashlamp-pumped Nd:YAG, and final stages will be flashlamp-pumped Nd:glass (silicate). Variable pulse width drive (0.3-20 ms) of the flashlamps is accomplished by insulated-gate bipolar transistor switching ofmore » large electrolytic capacitor banks. The burst train of laser pulses will enable the study of electron temperature (T{sub e}) and electron density (n{sub e}) dynamics in a single MST shot, and with ensembling, will enable correlation of T{sub e} and n{sub e} fluctuations with other fluctuating quantities.« less

1.5  kW efficient CW Nd:YAG planar waveguide MOPA laser.

PubMed

Wang, Juntao; Wu, Zhenhai; Su, Hua; Zhou, Tangjian; Lei, Jun; Lv, Wenqiang; He, Jing; Xu, Liu; Chen, Yuejian; Wang, Dan; Tong, Lixin; Hu, Hao; Gao, Qingsong; Tang, Chun

2017-08-15

In this Letter, we report a 1064 nm continuous wave Nd:YAG planar waveguide laser with an output power of 1544 W based on the structure of the master oscillator power amplification. A fiber laser is used as the master oscillator, and diode laser arrays are used as the pump source of the waveguide laser amplifier. The dimension of the waveguide is 1  mm (T)×10  mm (W)×60  mm (L), and the dual end oblique pumping is adopted with different angles. After a single-pass amplification, the power is scaled from 323 to 1544 W with the pump power of 2480 W, leading to an optical-to-optical efficiency of 49%. At the maximum output, the beam quality M 2 are measured to be 2.8 and 7.0 in the guided direction and the unguided direction, respectively. To the best of our knowledge, this is the highest output power of a Nd:YAG planar waveguide laser to date.

Transient Flows in a Pipe System with Pump Shut-Down and the Simultaneous Closing of a Spherical Valve

NASA Astrophysics Data System (ADS)

Zhang, Zh.

2016-11-01

Because of the limited value of the wave propagation speed in water the propagation of a pressure surge in transient flows can be tracked in the time series. This enables both the pressure head and the flow velocity in pipe flows to be determined as a function of both the coordinate along the pipe and the time. The propagation of the pressure surge includes both wave transmission and reflection. The latter occurs where the flow section is changed. The wave tracking method has been demonstrated as highly accurate and subsequently was applied to much more complex hydraulic systems, in which the pump is shut off and the spherical valve is simultaneously progressively closed. A combined four-quadrant characteristic of the pump and a spherical valve has been worked out, with which the computational procedure for the transient flow in the complex system could be significantly simplified. It has been demonstrated that not only the pressure surge in the hydraulic system but also the rotational speed of the pump could be satisfactorily computed. The computational algorithm has been demonstrated as quite simple, so that all calculations could be performed simply by means of the Microsoft Excel module.

Fluid Line Evacuation and Freezing Experiments for Digital Radiator Concept

NASA Technical Reports Server (NTRS)

Berisford, Daniel F.; Birur, Gajanana C.; Miller, Jennifer R.; Sunada, Eric T.; Ganapathi, Gani B.; Stephan, Ryan; Johnson, Mark

2011-01-01

The digital radiator technology is one of three variable heat rejection technologies being investigated for future human-rated NASA missions. The digital radiator concept is based on a mechanically pumped fluid loop with parallel tubes carrying coolant to reject heat from the radiator surface. A series of valves actuate to start and stop fluid flow to di erent combinations of tubes, in order to vary the heat rejection capability of the radiator by a factor of 10 or more. When the flow in a particular leg is stopped, the fluid temperature drops and the fluid can freeze, causing damage or preventing flow from restarting. For this reason, the liquid in a stopped leg must be partially or fully evacuated upon shutdown. One of the challenges facing fluid evacuation from closed tubes arises from the vapor generated during pumping to low pressure, which can cause pump cavitation and incomplete evacuation. Here we present a series of laboratory experiments demonstrating fluid evacuation techniques to overcome these challenges by applying heat and pumping to partial vacuum. Also presented are results from qualitative testing of the freezing characteristics of several different candidate fluids, which demonstrate significant di erences in freezing properties, and give insight to the evacuation process.

Fabricating microfluidic valve master molds in SU-8 photoresist

NASA Astrophysics Data System (ADS)

Dy, Aaron J.; Cosmanescu, Alin; Sluka, James; Glazier, James A.; Stupack, Dwayne; Amarie, Dragos

2014-05-01

Multilayer soft lithography has become a powerful tool in analytical chemistry, biochemistry, material and life sciences, and medical research. Complex fluidic micro-circuits require reliable components that integrate easily into microchips. We introduce two novel approaches to master mold fabrication for constructing in-line micro-valves using SU-8. Our fabrication techniques enable robust and versatile integration of many lab-on-a-chip functions including filters, mixers, pumps, stream focusing and cell-culture chambers, with in-line valves. SU-8 created more robust valve master molds than the conventional positive photoresists used in multilayer soft lithography, but maintained the advantages of biocompatibility and rapid prototyping. As an example, we used valve master molds made of SU-8 to fabricate PDMS chips capable of precisely controlling beads or cells in solution.

Biological proton pumping in an oscillating electric field

PubMed Central

Kim, Young C.; Furchtgott, Leon A.; Hummer, Gerhard

2010-01-01

Time-dependent external perturbations provide powerful probes of the function of molecular machines. Here we study biological proton pumping in an oscillating electric field. The protein cytochrome c oxidase is the main energy transducer in aerobic life, converting chemical energy into an electric potential by pumping protons across a membrane. With the help of master-equation descriptions that recover the key thermodynamic and kinetic properties of this biological “fuel cell,” we show that the proton pumping efficiency and the electronic currents in steady state both depend significantly and distinctly on the frequency and amplitude of the applied field, allowing us to distinguish between different microscopic mechanisms of the machine. A spectral analysis reveals dominant kinetic modes that show reaction steps consistent with an electron-gated pumping mechanism. PMID:20366348

Design study of magnetic eddy-current vibration suppression dampers for application to cryogenic turbomachinery

NASA Technical Reports Server (NTRS)

Gunter, E. J.; Humphris, R. R.; Severson, S. J.

1983-01-01

Cryogenic turbomachinery used to pump high pressure fuel (liquid H2) and oxidizer (liquid O2) to the main engines of the Space Shuttle have experienced rotor instabilities. Subsynchronous whirl, an extremely destructive instability, has caused bearing failures and severe rubs in the seals. These failures have resulted in premature engine shutdowns or, in many instances, have limited the power level to which the turbopumps could be operated. The feasibility of using an eddy current type of damping mechanism for the Space Shuttle Main Engine is outlined.

APT Blanket System Loss-of-Coolant Accident (LOCA) Based on Initial Conceptual Design - Case 2: with Beam Shutdown Only

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

Hamm, L.L.

1998-10-07

This report is one of a series of reports that document normal operation and accident simulations for the Accelerator Production of Tritium (APT) blanket heat removal system. These simulations were performed for the Preliminary Safety Analysis Report. This report documents the results of simulations of a Loss-of-Flow Accident (LOFA) where power is lost to all of the pumps that circulate water in the blanket region, the accelerator beam is shut off and neither the residual heat removal nor cavity flood systems operate.

Orbit Transfer Vehicle (OTV) engine phase A study

NASA Technical Reports Server (NTRS)

Mellish, J. A.

1978-01-01

Requirements for the orbit transfer vehicle engine were examined. Engine performance/weight sensitivities, the effect of a service life of 300 start/shutdown cycles between overalls on the maximum engine operating pressure, and the sensitivity of the engine design point (i.e., thrust chamber pressure and nozzle area ratio) to the performance requirements specified are among the factors studied. Preliminary engine systems analyses were conducted on the stage combustion, expander, and gas generator engine cycles. Hydrogen and oxygen pump discharge pressure requirements are shown for various engine cycles. Performance of the engine cycles is compared.

Recent GPS Results at SLAC

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

Behrend, Dirk; Imfeld, Hans L.; /SLAC

2005-08-17

The Alignment Engineering Group (AEG) makes use of GPS technology for fulfilling part of its above ground surveying tasks at SLAC since early 2002. A base station (SLAC M40) has been set up at a central location of the SLAC campus serving both as master station for real-time kinematic (RTK) operations and as datum point for local GPS campaigns. The Leica RS500 system is running continuously and the GPS data are collected both externally (logging PC) and internally (receiver flashcard). The external logging is facilitated by a serial to Ethernet converter and an Ethernet connection at the station. Internal loggingmore » (ring buffer) is done for data security purposes. The weatherproof boxes for the instrumentation are excellent shelters against rain and wind, but do heat up considerably in sun light. Whereas the GPS receiver showed no problems, the Pacific Crest PDL 35 radio shut down several times due to overheating disrupting the RTK operations. In order to prevent heat-induced shutdowns, a protection against direct sun exposure (shading) and a constant air circulation system (ventilation) were installed. As no further shutdowns have occurred so far, it appears that the two measures successfully mended the heat problem.« less

[The shutdown point and the output volume limit (OVL) in the present situation of healthcare in Hungary (or a little economics for practicing physicians)].

PubMed

Gresz, Miklós

2008-09-07

In the present situation of health care, financing has become so complicated that the treating doctor has to know not only his profession but also has to consider the different regulations, laws and book of rules. The work of the physician cannot be carried out only through the fact that he is a master of his art, that is healing. All healing practice, diagnostic abilities, intuition, empathy and other things are in vain: if he is not familiar with the basics of financing he can lead his institution to insolvency. This article tries to give a view of a small part of financing, the output volume limit (OVL) from another aspect. According to the basics of economy and general rules of leadership it tries to show up the practical difficulties of the output volume limit. The study enlightens that by defining the output volume limit one has to consider the shutdown point of the hospital and knowing this, the actual output volume limit should be defined in the way that it does not make the proper activity of the hospital completely impossible.

Self-seeded single-frequency solid-state ring laser and system using same

DOEpatents

Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

2007-02-20

A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

Self-seeded single-frequency laser peening method

DOEpatents

Dane, C Brent [Livermore, CA; Hackel, Lloyd [Livermore, CA; Harris, Fritz B [Rocklin, CA

2009-08-11

A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

Self-seeded single-frequency laser peening method

DOEpatents

DAne, C Brent; Hackey, Lloyd A; Harris, Fritz B

2012-06-26

A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

One joule output from a diode-array-pumped Nd:YAG laser with side-pumped rod geometry

NASA Technical Reports Server (NTRS)

Kasinski, Jeffrey J.; Hughes, Will; Dibiase, Don; Bournes, Patrick; Burnham, Ralph

1992-01-01

Output of 1.25 J per pulse (1.064 micron) with an absolute optical efficiency of 28 percent and corresponding electrical efficiency of 10 percent was demonstrated in a diode-array-pumped Nd:YAG laser using a side-pumped rod geometry in a master-oscillator/power-amplifier configuration. In Q-switched operation, an output of 0.75 J in a 17-ns pulse was obtained. The fundamental laser output was frequency doubled in KTP with 60 percent conversion efficiency to obtain 0.45 J in a 16-ns pulse at 532 nm. The output beam had high spatial quality with pointing stability better than 40 microrad and a shot-to-shot pulse energy fluctuation of less than +/-3 percent.

Theoretical analyses of an injection-locked diode-pumped rubidium vapor laser.

PubMed

Cai, He; Gao, Chunqing; Liu, Xiaoxu; Wang, Shunyan; Yu, Hang; Rong, Kepeng; An, Guofei; Han, Juhong; Zhang, Wei; Wang, Hongyuan; Wang, You

2018-04-02

Diode-pumped alkali lasers (DPALs) have drawn much attention since they were proposed in 2001. The narrow-linewidth DPAL can be potentially applied in the fields of coherent communication, laser radar, and atomic spectroscopy. In this study, we propose a novel protocol to narrow the width of one kind of DPAL, diode-pumped rubidium vapor laser (DPRVL), by use of an injection locking technique. A kinetic model is first set up for an injection-locked DPRVL with the end-pumped configuration. The laser tunable duration is also analyzed for a continuous wave (CW) injection-locked DPRVL system. Then, the influences of the pump power, power of a master laser, and reflectance of an output coupler on the output performance are theoretically analyzed. The study should be useful for design of a narrow-linewidth DPAL with the relatively high output.

Analysis of boron dilution in a four-loop PWR

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

Sun, J.G.; Sha, W.T.

1995-12-31

Thermal mixing and boron dilution in a pressurized water reactor were analyzed with COMMIX codes. The reactor system was the four loop Zion reactor. Two boron dilution scenarios were analyzed. In the first scenario, the plant is in cold shutdown and the reactor coolant system has just been filled after maintenance on the steam generators. To flush the air out of the steam generator tubes, a reactor coolant pump (RCP) is started, with the water in the pump suction line devoid of boron and at the same temperature as the coolant in the system. In the second scenario, the plantmore » is at hot standby and the reactor coolant system has been heated up to operating temperature after a long outage. It is assumed that an RCP is started, with the pump suction line filled with cold unborated water, forcing a slug of diluted coolant down the downcomer and subsequently through the reactor core. The subsequent transient thermal mixing and boron dilution that would occur in the reactor system is simulated for these two scenarios. The reactivity insertion rate and the total reactivity are evaluated.« less

Passive shut-down heat removal system

DOEpatents

Hundal, Rolv; Sharbaugh, John E.

1988-01-01

An improved shut-down heat removal system for a liquid metal nuclear reactor of the type having a vessel for holding hot and cold pools of liquid sodium is disclosed herein. Generally, the improved system comprises a redan or barrier within the reactor vessel which allows an auxiliary heat exchanger to become immersed in liquid sodium from the hot pool whenever the reactor pump fails to generate a metal-circulating pressure differential between the hot and cold pools of sodium. This redan also defines an alternative circulation path between the hot and cold pools of sodium in order to equilibrate the distribution of the decay heat from the reactor core. The invention may take the form of a redan or barrier that circumscribes the inner wall of the reactor vessel, thereby defining an annular space therebetween. In this embodiment, the bottom of the annular space communicates with the cold pool of sodium, and the auxiliary heat exchanger is placed in this annular space just above the drawn-down level that the liquid sodium assumes during normal operating conditions. Alternatively, the redan of the invention may include a pair of vertically oriented, concentrically disposed standpipes having a piston member disposed between them that operates somewhat like a pressure-sensitive valve. In both embodiments, the cessation of the pressure differential that is normally created by the reactor pump causes the auxiliary heat exchanger to be immersed in liquid sodium from the hot pool. Additionally, the redan in both embodiments forms a circulation flow path between the hot and cold pools so that the decay heat from the nuclear core is uniformly distributed within the vessel.

Control of reactor coolant flow path during reactor decay heat removal

DOEpatents

Hunsbedt, Anstein N.

1988-01-01

An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

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

Steiner, J.L.; Lime, J.F.; Elson, J.S.

One dimensional TRAC transient calculations of the process inherent ultimate safety (PIUS) advanced reactor design were performed for a pump-trip SCRAM. The TRAC calculations showed that the reactor power response and shutdown were in qualitative agreement with the one-dimensional analyses presented in the PIUS Preliminary Safety Information Document (PSID) submitted by Asea Brown Boveri (ABB) to the US Nuclear Regulatory Commission for preapplication safety review. The PSID analyses were performed with the ABB-developed RIGEL code. The TRAC-calculated phenomena and trends were also similar to those calculated with another one-dimensional PIUS model, the Brookhaven National Laboratory developed PIPA code. A TRACmore » pump-trip SCRAM transient has also been calculated with a TRAC model containing a multi-dimensional representation of the PIUS intemal flow structures and core region. The results obtained using the TRAC fully one-dimensional PIUS model are compared to the RIGEL, PIPA, and TRAC multi-dimensional results.« less

Understanding and Resolution of the Block 2 SSME, STS-104 Engine Shutdown Pressure Surge In-flight Anomaly

NASA Technical Reports Server (NTRS)

Greene, William D.; Kynard, Michael H.; Tiller, Bruce K. (Technical Monitor)

2002-01-01

STS-104, launched July 2001, marked the first flight of a single Block 2 Space Shuttle Main Engine (SSME). This new configuration of the SSME is the culmination of well over a decade of gradual engine system upgrades. The launch and mission were a success. However, in the process of post-launch data analysis a Main Propulsion System (MPS) anomaly was noted and tied directly to the shutdown of the Block 2 SSME. An investigation into this anomaly was organized across NASA facilities and across the various hardware component contractors. This paper is a very brief summary of the eventual understanding of the root causes of the anomaly and the process whereby an appropriate mitigation action was proposed. An analytical model of the High Pressure Fuel Pump (HPFP) and the low pressure fuel system of the SSME is presented to facilitate the presentation of this summary. The proposed mitigation action is discussed and, with the launch of STS-108 in November 2001, successfully demonstrated under flight conditions.

The search of the best mode of the reserve power supply consumption during the nuclear reactor’s emergency shutdown procedures in case of force majeure circumstances

NASA Astrophysics Data System (ADS)

Zagrebaev, A. M.; Trifonenkov, A. V.

2017-01-01

This article deals with the problem of the control mode choice for a power supply system in case of force majeure circumstances. It is not known precisely, when a force majeure incident occurs, but the threatened period is given, when the incident is expected. It is supposed, that force majeure circumstances force nuclear reactor shutdown at the moment of threat coming. In this article the power supply system is considered, which consists of a nuclear reactor and a reserve power supply, for example, a hydroelectric pumped storage power station. The reserve power supply has limited capacity and it doesn’t undergo the threatened incident. The problem of the search of the best reserve supply time-distribution in case of force majeure circumstances is stated. The search is performed according to minimization of power loss and damage to the infrastructure. The software has been developed, which performs automatic numerical search of the approximate optimal control modes for the reserve power supply.

2-Micron Laser Transmitter for Coherent CO2 DIAL Measurement

NASA Technical Reports Server (NTRS)

Singh, Upendra N.; Bai, Yingxin; Yu, Jirong

2009-01-01

Carbon dioxide (CO2) has been recognized as one of the most important greenhouse gases. It is essential for the study of global warming to accurately measure the CO2 concentration in the atmosphere and continuously record its variation. A high repetition rate, highly efficient, Q-switched 2-micron laser system as the transmitter of a coherent differential absorption lidar for CO2 measurement has been developed in NASA Langley Research Center. This laser system is capable of making a vertical profiling of CO2 from ground and column measurement of CO2 from air and space-borne platform. The transmitter is a master-slave laser system. The master laser operates in a single frequency, either on-line or off-line of a selected CO2 absorption line. The slave laser is a Q-switched ring-cavity Ho:YLF laser which is pumped by a Tm:fiber laser. The repetition rate can be adjusted from a few hundred Hz to 10 kHz. The injection seeding success rate is from 99.4% to 99.95%. For 1 kHz operation, the output pulse energy is 5.5mJ with the pulse length of 50 ns. The optical-to-optical efficiency is 39% when the pump power is 14.5W. A Ho:YLF laser operating in the range of 2.05 micrometers can be tuned over several characteristic lines of CO2 absorption. Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of CO2 with a repetition rate of 5 Hz and pulse energy of 75 mJ. For coherent detection, high repetition rate is required for speckle averaging to obtain highly precise measurements. However, a diode pumped Ho:Tm:YLF laser can not operate in high repetition rate due to the large heat loading and up-conversion. A Tm:fiber laser pumped Ho:YLF laser with low heat loading can operate in high repetition rate. A theoretical model has been established to simulate the performance of Tm:fiber laser pumped Ho:YLF lasers. For continuous wave (CW) operation, high pump intensity with small beam size is suitable for high efficiency. For Q-switched operation, the optimal energy extraction relies on the pump intensity, pump volume, and pump duration which is inversely proportion to the repetition rate. CW and Q-switched Ho:YLF lasers with different linear cavity configurations have been designed and demonstrated for a 30 W Tm:fiber pump laser. The CW Ho laser slope efficiency and optical-to-optical efficiencies reach 65% and 55%, respectively. The pulsed laser efficiency depends on the repetition rate. For 1 kHz operation, the optical-to-optical efficiency is 39% when the pump power is 14.5W. Currently, the injection seeding success rate is between 99.4% and 99.95%. After a ten thousand pulses, the standard deviation of the laser frequency jitter is about 3 MHz. It meets the requirements of highly precise CO2 concentration measurement. In conclusion, an injection seeded, high repetition rate, Q-switched Ho:YLF laser has been developed for a coherent CO2 differential absorption lidar. This master-slave laser system has high optical-to-optical efficiency and seeding success rate. It can potentially meet the requirements of the coherent detection of CO2 concentration by a differential absorption lidar technique.

Principles of passive and active cooling of mirror-based hybrid systems employing liquid metals

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

Anglart, Henryk

This paper presents principles of passive and active cooling that are suitable to mirrorbased hybrid, nuclear fission/fusion systems. It is shown that liquid metal lead-bismuth cooling of the mirror machine with 25 m height and 1.5 GW thermal power is feasible both in the active mode during the normal operation and in the passive mode after the reactor shutdown. In the active mode the achievable required pumping power can well be below 50 MW, whereas the passive mode provides enough coolant flow to keep the clad temperature below the damage limits.

Principles of passive and active cooling of mirror-based hybrid systems employing liquid metals

NASA Astrophysics Data System (ADS)

Anglart, Henryk

2012-06-01

This paper presents principles of passive and active cooling that are suitable to mirrorbased hybrid, nuclear fission/fusion systems. It is shown that liquid metal lead-bismuth cooling of the mirror machine with 25 m height and 1.5 GW thermal power is feasible both in the active mode during the normal operation and in the passive mode after the reactor shutdown. In the active mode the achievable required pumping power can well be below 50 MW, whereas the passive mode provides enough coolant flow to keep the clad temperature below the damage limits.

Peristaltic pump-based low range pressure sensor calibration system

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

Vinayakumar, K. B.; Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore 5600012; Naveen Kumar, G.

2015-11-15

Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressuremore » leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.« less

Peristaltic pump-based low range pressure sensor calibration system

NASA Astrophysics Data System (ADS)

Vinayakumar, K. B.; Naveen Kumar, G.; Nayak, M. M.; Dinesh, N. S.; Rajanna, K.

2015-11-01

Peristaltic pumps were normally used to pump liquids in several chemical and biological applications. In the present study, a peristaltic pump was used to pressurize the chamber (positive as well negative pressures) using atmospheric air. In the present paper, we discuss the development and performance study of an automatic pressurization system to calibrate low range (millibar) pressure sensors. The system includes a peristaltic pump, calibrated pressure sensor (master sensor), pressure chamber, and the control electronics. An in-house developed peristaltic pump was used to pressurize the chamber. A closed loop control system has been developed to detect and adjust the pressure leaks in the chamber. The complete system has been integrated into a portable product. The system performance has been studied for a step response and steady state errors. The system is portable, free from oil contaminants, and consumes less power compared to existing pressure calibration systems. The veracity of the system was verified by calibrating an unknown diaphragm based pressure sensor and the results obtained were satisfactory.

Yb:YAG master oscillator power amplifier for remote wind sensing.

PubMed

Sridharan, A K; Saraf, S; Byer, R L

2007-10-20

We have demonstrated key advances towards a solid-state laser amplifier at 1.03 microm for global remote wind sensing. We designed end-pumped zig-zag slab amplifiers to achieve high gain. We overcame parasitic oscillation limitations using claddings on the slab's total internal reflection (TIR) and edge surfaces to confine the pump and signal light by TIR and allow leakage of amplified spontaneous emission rays that do not meet the TIR condition. This enables e3, e5, and e8 single-, double-, and quadruple-pass small-signal amplifier gain, respectively. The stored energy density is 15.6 J/cm3, a record for a laser-diode end-pumped Yb:YAG zig-zag slab amplifier.

Research on High-Intensity Picosecond Pump Laser in Short Pulse Optical Parametric Amplification

NASA Astrophysics Data System (ADS)

Pan, Xue; Peng, Yu-Jie; Wang, Jiang-Feng; Lu, Xing-Hua; Ouyang, Xiao-Ping; Chen, Jia-Lin; Jiang, You-En; Fan, Wei; Li, Xue-Chun

2013-01-01

A 527 nm pump laser generating 1.7 mJ energy with peak power of more than 0.12 GW is demonstrated. The theoretical simulation result shows that it has 106 gain in the picosecond-pump optical parametric chirped pulse amplification when the pump laser peak power is 0.1 GW and the intensity is more than 5 GW/cm2, and that it can limit the parametric fluorescence in the picosecond time scale of pump duration. The pump laser system adopts a master-oscillator power amplifier, which integrates a more than 30 pJ fiber-based oscillator with a 150 μJ regenerative amplifier and a relay-imaged four-pass diode-pump Nd glass amplifier to generate a 1 Hz top hat spatial beam and about 14 ps temporal Guassian pulse with <2% pulse-to-pulse energy stability. The output energy of the power amplifier is limited to 4 mJ for B-integral concern, and the frequency doubling efficiency can reach 65% with input intensity 10 GW/cm2.

High Repetition Rate Pulsed 2-Micron Laser Transmitter for Coherent CO2 DIAL Measurement

NASA Technical Reports Server (NTRS)

Singh, Uprendra N.; Bai, Yingxin; Yu, Jirong; Petros, Mulugeta; Petzar, Paul J.; Trieu, Bo C.; Lee, Hyung

2009-01-01

A high repetition rate, highly efficient, Q-switched 2-micron laser system as the transmitter of a coherent differential absorption lidar for CO2 measurement has been developed at NASA Langley Research Center. Such a laser transmitter is a master-slave laser system. The master laser operates in a single frequency, either on-line or off-line of a selected CO2 absorption line. The slave laser is a Q-switched ring-cavity Ho:YLF laser which is pumped by a Tm:fiber laser. The repetition rate can be adjusted from a few hundred Hz to 10 kHz. The injection seeding success rate is from 99.4% to 99.95%. For 1 kHz operation, the output pulse energy is 5.5mJ with the pulse length of approximately 50 ns. The optical-to-optical efficiency is 39% when the pump power is 14.5W. The measured standard deviation of the laser frequency jitter is about 3 MHz.

Microsecond gain-switched master oscillator power amplifier (1958 nm) with high pulse energy

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

Ke Yin; Weiqiang Yang; Bin Zhang

2014-02-28

An all-fibre master oscillator power amplifier (MOPA) emitting high-energy pulses at 1958 nm is presented. The seed laser is a microsecond gain-switched thulium-doped fibre laser (TDFL) pumped with a commercial 1550-nm pulsed fibre laser. The TDFL operates at a repetition rate f in the range of 10 to 100 kHz. The two-stage thulium-doped fibre amplifier is built to scale the energy of the pulses generated by the seed laser. The maximum output pulse energy higher than 0.5 mJ at 10 kHz is achieved which is comparable with the theoretical maximum extractable pulse energy. The slope efficiency of the second stagemore » amplifier with respect to the pump power is 30.4% at f = 10 kHz. The wavelength of the output pulse laser is centred near 1958 nm at a spectral width of 0.25 nm after amplification. Neither nonlinear effects nor significant amplified spontaneous emission (ASE) is observed in the amplification experiments. (lasers)« less

Single-mode single-frequency high peak power all-fiber MOPA at 1550 nm

NASA Astrophysics Data System (ADS)

Kotov, L. V.; Likhachev, M. E.; Bubnov, M. M.; Paramonov, V. M.; Belovolov, M. I.; Lipatov, D. S.; Guryanov, A. N.

2014-10-01

In this Report, we present a record-high-peak-power single-frequency master oscillator power amplifier (MOPA) system based on a newly developed double-clad large-mode-area Yb-free Er-doped fiber (DC-LMA-EDF). A fiber Bragg grating wavelength-stabilized fiber-coupled diode laser at λ=1551 nm with ~2 MHz spectral width was used as the master oscillator. Its radiation was externally modulated with a 5 kHz repetition rate and 92 ns pulse duration and then amplified in a core-pumped Er-doped fiber amplifier up to an average power of 4 mW. The amplified spontaneous emission (ASE) generated at the last preamplifier stage was suppressed by a narrow-band (0.7 nm) DWDM filter. The last MOPA stage was based on the recently developed single-mode DC-LMA-EDF with a mode field diameter of 25 microns and pump clad-absorption of 3 dB/m at λ=980 nm. The pump and the signal were launched into this fiber through a commercial pump combiner in a co-propagating amplifier scheme. At first, we used a 3-m long DC-LMAEDF. In such configuration, a peak power of 800 W was achieved at the output of the amplifier together with a ~ 12 % pump conversion slope efficiency. Further power scaling was limited by SBS. After that we shortened the fiber length to 1 m. As a result, owing to large unabsorbed pump power, the efficiency decreased to ~5 %. However, a peak power of more than 3.5 kW was obtained before the SBS threshold. In this case, the pulse shape changed and its duration decreased to ~60 ns owing to inversion depletion after propagation of the forward front of the pulse. To the best of our knowledge, the peak power of more than 3.5 kW reported here is the highest value ever published for a single-frequency single-mode silica-based fiber laser system operating near λ=1550 nm.

1047nm 270mJ all solid state diode pumped MOPA at 50 Hz

NASA Astrophysics Data System (ADS)

Ma, Jian; Yang, Qi; Lu, Tingting; Ma, Xiuhua; Zhu, Xiaolei; Chen, Weibiao

2015-02-01

A diode-pumped nanosecond Master Oscillator Power Amplifier (MOPA) system based on Nd:YLF crystal slabs has been demonstrated. The seed pulses with pulse duration of 11 ns were generated in an EO Q-switched Nd:YLF laser, with single pulse energy of 10 mJ. The 1047 nm signal pulses were amplified in a double-pass amplification system. Maximum output pulse energy of 270 mJ at a repetition rate of 50 Hz has been achieved with effective optical-to-optical efficiency of 14.5%.

One-Joule-per-Pulse Q-Switched 2-micron Solid State Laser

NASA Technical Reports Server (NTRS)

Yu, Jirong; Trieu, Bo C.; Modlin, Ed A.; Singh, Upendra N.; Kavaya, Michael J.; Chen, Songsheng; Bai, Yingxin; Petzar, Pual J.; Petros, Mulugeta

2005-01-01

Q-switched output of 1.1 J per pulse at 2-micron wavelength has been achieved in a diode pumped Ho:Tm:LuLF laser using a side-pumped rod configuration in a Master-Oscillator-Power-Amplifier (MOPA) architecture. This is the first time that a 2-micron laser has broken the Joule per pulse barrier for Q-switched operation. The total system efficiency reaches 5% and 6.2% for single and double pulse operation, respectively. The system produces excellent 1.4 times of transform limited beam quality.

Effects of decreased ground-water withdrawal on ground-water levels and chloride concentrations in Camden County, Georgia, and ground-water levels in Nassau County, Florida, from September 2001 to May 2003

USGS Publications Warehouse

Peck, Michael F.; McFadden, Keith W.; Leeth, David C.

2005-01-01

During October 2002, the Durango Paper Company formerly Gillman Paper Company) in St. Marys, Georgia, shut down paper-mill operations; the shutdown resulted in decreased ground-water withdrawal in Camden County by 35.6 million gallons per day. The decrease in withdrawal resulted in water-level rise in wells completed in the Floridan aquifer system and the overlying surficial and Brunswick aquifer systems; many wells in the St. Marys area flowed for the first time since the mill began operations during 1941. Pumping at the mill resulted in the development of a cone of depression that coalesced with a larger adjacent cone of depression at Fernandina Beach, Florida. Since closure of the mill, the cone at St. Marys is no longer present, although the cone still exists at Fernandina Beach, Florida. Historical water-level data from the production wells at the mill indicate that the pumping water level ranged from 68 to 235 feet (ft) below North American Vertical Datum of 1988 (NAVD 88) and averaged about 114 ft when the mill was operating. Since the shutdown, it is estimated that water levels at the mill have risen about 140 ft and are now at about 30 ft above NAVD 88. The water-level rise in wells in outlying areas in Camden County was less pronounced and ranged from about 5 to 10 ft above NAVD 88. Because of the regional upward water-level trend in the Upper Floridan aquifer that started during 19992000 in most of the coastal area, combined with a steeper upward trend beginning during October 2002, it was not possible to determine if the 510 ft rise in water levels in wells away from St. Marys was due to the mill closure. In addition to water-level rise of 2226 ft in the Floridan aquifer system, water-level rises in the overlying surficial and Brunswick aquifer systems at St. Marys after the shutdown indicate upward leakage of water. Water levels had stabilized in the confined surficial and Upper and Lower Floridan aquifers by AprilMay 2003; however, the water level in the upper Brunswick aquifer was still rising as of May 2003. Chloride concentrations in the Upper Floridan aquifer in Camden County do not exceed the State and Federal drinking-water standard of 250 milligrams per liter (mg/L). With the exception of three wells located at St. Marys, all of the wells sampled during this study (from September 2002 to May 2003) had chloride concentrations ranging from 30 to 50 mg/L, which are considered within background levels for the Upper Floridan aquifer in this area. The three wellstwo at the Durango Paper Company and the other an old unused City of St. Marys wellhad chloride concentrations that ranged from 74 to 175 mg/L, which are above the background level, but were still below the 250-mg/L drinking-water standard. The source has not been determined for the elevated chloride concentration in these wells; the chloride concentration in one of the wells has decreased slightly since the paper-mill shutdown. Chloride concentrations throughout Camden County showed little change after the paper-mill shutdown.

Sodium storage and injection system

NASA Technical Reports Server (NTRS)

Keeton, A. R. (Inventor)

1979-01-01

A sodium storage and injection system for delivering atomized liquid sodium to a chemical reactor employed in the production of solar grade silicon is disclosed. The system is adapted to accommodate start-up, shut-down, normal and emergency operations, and is characterized by (1) a jacketed injection nozzle adapted to atomize liquefied sodium and (2) a supply circuit connected to the nozzle for delivering the liquefied sodium. The supply circuit is comprised of a plurality of replaceable sodium containment vessels, a pump interposed between the vessels and the nozzle, and a pressurizing circuit including a source of inert gas connected with the vessels for maintaining the sodium under pressure.

Fast-acting nuclear reactor control device

DOEpatents

Kotlyar, Oleg M.; West, Phillip B.

1993-01-01

A fast-acting nuclear reactor control device for moving and positioning a fety control rod to desired positions within the core of the reactor between a run position in which the safety control rod is outside the reactor core, and a shutdown position in which the rod is fully inserted in the reactor core. The device employs a hydraulic pump/motor, an electric gear motor, and solenoid valve to drive the safety control rod into the reactor core through the entire stroke of the safety control rod. An overrunning clutch allows the safety control rod to freely travel toward a safe position in the event of a partial drive system failure.

Fast Flux Test Facility thermal and pressure transient events during Cycle 11

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

Ahrens, D. M.

1992-03-01

This report documents the thermal and pressure transients experienced by the Reactor Heat Transport System (RHTS) during Cycle 11 which included Cycles 11A, 11B-1, 11B-2 and 11C (i.e. 4 startups and 4 shutdowns). Cycle 11 consisted of a refueling period that began on March 14, 1989 and power operation which began on May 3, 1989 and ended on October 27, 1990. Transients resulted from secondary pump starts/stops while at refueling conditions. The major causes of transients at power were five unplanned reactor scrams from 100% power and problems with Loop 2 DHX Fan Controls During 11A.

30 CFR 250.602 - Equipment movement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.602 Equipment movement... surface with a pump-through-type tubing plug and at the surface with a closed master valve prior to moving...

30 CFR 250.502 - Equipment movement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.502 Equipment movement... surface with a pump-through-type tubing plug and at the surface with a closed master valve prior to moving...

Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand

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

Sarkar, C.K.; Pandit, D.R.; Kwon, S.G.

The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of coolingmore » towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.« less

Lessons learned: design, start-up, and operation of cryogenic systems

NASA Astrophysics Data System (ADS)

Bell, W. M.; Bagley, R. E.; Motew, S.; Young, P.-W.

2014-11-01

Cryogenic systems involving a pumped cryogenic fluid, such as liquid nitrogen (LN2), require careful design since the cryogen is close to its boiling point and cold. At 1 atmosphere, LN2 boils at 77.4 K (-320.4 F). These systems, typically, are designed to transport the cryogen, use it for process heat removal, or for generation of gas (GN2) for process use. As the design progresses, it is important to consider all aspects of the design including, cryogen storage, pressure control and safety relief systems, thermodynamic conditions, equipment and instrument selection, materials, insulation, cooldown, pump start-up, maximum design and minimum flow rates, two phase flow conditions, heat flow, process control to meet and maintain operating conditions, piping integrity, piping loads on served equipment, warm-up, venting, and shut-down. "Cutting corners" in the design process can result in stalled start-ups, field rework, schedule hits, or operational restrictions. Some of these "lessoned learned" are described in this paper.

SSME turbopump bearing analytical study

NASA Technical Reports Server (NTRS)

Kannel, J. W.; Merriman, T.

1980-01-01

Three shuttle pump bearings operating under severe overspeed and shut-down conditions are evaluated. The specific parameters investigated include outer race stresses, cage stresses, cage-race drag, bearing heating, and crush loading. A quasi-dynamic version of the BASDAP computer code was utilized which involved the calculation of ball-race forces (inner and outer), contact pressures, contact dimensions, and contact angles as a function of (1) axial load, (2) radial load, and (3) centrifugal load on the bearing. Generally, radial loads on the order of 13,300 N (3000 pounds) per bearing or 26,700 N (6000 pounds) per bearing pair, could be expected to cause severe problems to any of the bearings with a 17,800 N (4000 pounds) axial load. Further, when possible temperature excursions are considered, even a load of 8900 N (2000 pounds) may be excessive. However, high momentary radial loads with a 3800 N (850 pounds) axial load would not be anticipated to cause catastrophic failure of the fuel pump bearing.

Impact of mixing chemically heterogeneous groundwaters on the sustainability of an open-loop groundwater heat pump

NASA Astrophysics Data System (ADS)

Burté, L.; Farasin, J.; Cravotta, C., III; Gerard, M. F.; Cotiche Baranger, C.; Aquilina, L.; Le Borgne, T.

2017-12-01

Geothermal systems using shallow aquifers are commonly used for heating and cooling. The sustainability of these systems can be severely impacted by the occurrence of clogging process. The geothermal loop operation (including pumping of groundwater, filtering and heat extraction through exchangers and cooled water injection) can lead to an unexpected biogeochemical reactivity and scaling formation that can ultimately lead to the shutdown of the geothermal doublet. Here, we report the results of investigations carried out on a shallow geothermal doublet (< 40 m depth) affected by rapid clogging processes linked to iron and manganese oxidation. Using a reactive transport model, we determine the parameters controlling clogging. To characterize the biogeochemical processes induced by the operation of the production well, we combined hydrodynamic measurements by flowmeter and in-situ chemical depth profiles. We thus investigated the chemical heterogeneity into the pumping well as a function of the operating conditions (static or dynamic). Hydrochemical data collected at the pumping well showed that groundwater was chemically heterogeneous long the 11 meters well screen. While the aquifer was dominantly oxic, a localized inflow of anoxic water was detected and evaluated to produce about 40% of the total flow . The mixture of chemically heterogeneous water induced by pumping lead to the oxidation of reductive species and thus to the formation of biogenic precipitates responsible for clogging. The impact of pumping waters of different redox potential and chemical characteristics was quantified by numerical modeling using PHREEQC. These results shows that natural chemical heterogeneity can occur at a small scale in heterogeneous aquifers and highlight the importance of their characterization during the production well testing and the geothermal loop operation in order to take preventive measures to avoid clogging.

Fuel cell system logic for differentiating between rapid and normal shutdown commands

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2000-01-01

A method of controlling the operation of a fuel cell system wherein each shutdown command for the system is subjected to decision logic which determines whether the command should be a normal shutdown command or rapid shutdown command. If the logic determines that the shutdown command should be a normal shutdown command, then the system is shutdown in a normal step-by-step process in which the hydrogen stream is consumed within the system. If the logic determines that the shutdown command should be a rapid shutdown command, the hydrogen stream is removed from the system either by dumping to atmosphere or routing to storage.

High-brightness 800nm fiber-coupled laser diodes

NASA Astrophysics Data System (ADS)

Berk, Yuri; Levy, Moshe; Rappaport, Noam; Tessler, Renana; Peleg, Ophir; Shamay, Moshe; Yanson, Dan; Klumel, Genadi; Dahan, Nir; Baskin, Ilya; Shkedi, Lior

2014-03-01

Fiber-coupled laser diodes have become essential sources for fiber laser pumping and direct energy applications. Single emitters offer reliable multi-watt output power from a 100 m lateral emission aperture. By their combination and fiber coupling, pump powers up to 100 W can be achieved from a low-NA fiber pigtail. Whilst in the 9xx nm spectral range the single emitter technology is very mature with <10W output per chip, at 800nm the reliable output power from a single emitter is limited to 4 W - 5 W. Consequently, commercially available fiber coupled modules only deliver 5W - 15W at around 800nm, almost an order of magnitude down from the 9xx range pumps. To bridge this gap, we report our advancement in the brightness and reliability of 800nm single emitters. By optimizing the wafer structure, laser cavity and facet passivation process we have demonstrated QCW device operation up to 19W limited by catastrophic optical damage to the 100 μm aperture. In CW operation, the devices reach 14 W output followed by a reversible thermal rollover and a complete device shutdown at high currents, with the performance fully rebounded after cooling. We also report the beam properties of our 800nm single emitters and provide a comparative analysis with the 9xx nm single emitter family. Pump modules integrating several of these emitters with a 105 μm / 0.15 NA delivery fiber reach 35W in CW at 808 nm. We discuss the key opto-mechanical parameters that will enable further brightness scaling of multi-emitter pump modules.

System Control Applications of Low-Power Radio Frequency Devices

NASA Astrophysics Data System (ADS)

van Rensburg, Roger

2017-09-01

This paper conceptualizes a low-power wireless sensor network design for application employment to reduce theft of portable computer devices used in educational institutions today. The aim of this study is to design and develop a reliable and robust wireless network that can eradicate accessibility of a device’s human interface. An embedded system supplied by an energy harvesting source, installed on the portable computer device, may represent one of multiple slave nodes which request regular updates from a standalone master station. A portable computer device which is operated in an undesignated area or in a field perimeter where master to slave communication is restricted, indicating a possible theft scenario, will initiate a shutdown of its operating system and render the device unusable. Consequently, an algorithm in the device firmware may ensure the necessary steps are executed to track the device, irrespective whether the device is enabled. Design outcomes thus far indicate that a wireless network using low-power embedded hardware, is feasible for anti-theft applications. By incorporating one of the latest Bluetooth low-energy, ANT+, ZigBee or Thread wireless technologies, an anti-theft system may be implemented that has the potential to reduce major portable computer device theft in institutions of digitized learning.

Development of high-power dye laser chain

NASA Astrophysics Data System (ADS)

Konagai, Chikara; Kimura, Hironobu; Fukasawa, Teruichiro; Seki, Eiji; Abe, Motohisa; Mori, Hideo

2000-01-01

Copper vapor laser (CVL) pumped dye laser (DL) system, both in a master oscillator power amplifier (MOPA) configuration, has been developed for Atomic Vapor Isotope Separation program in Japan. Dye laser output power of about 500 W has been proved in long-term operations over 200 hours. High power fiber optic delivery system is utilized in order to efficiently transport kilowatt level CVL beams to the DL MOPA. Single model CVL pumped DL oscillator has been developed and worked for 200 hours within +/- 0.1 pm wavelength stability. Phase modulator for spreading spectrum to the linewidth of hyperfine structure has been developed and demonstrated.

46 CFR 154.1850 - Entering cargo handling spaces.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Entering cargo handling spaces. 154.1850 Section 154... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps...

46 CFR 154.1850 - Entering cargo handling spaces.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Entering cargo handling spaces. 154.1850 Section 154... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps...

46 CFR 154.1850 - Entering cargo handling spaces.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Entering cargo handling spaces. 154.1850 Section 154... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps...

46 CFR 154.1850 - Entering cargo handling spaces.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Entering cargo handling spaces. 154.1850 Section 154... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps...

46 CFR 154.1850 - Entering cargo handling spaces.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Entering cargo handling spaces. 154.1850 Section 154... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps...

Multi-Watt femtosecond optical parametric master oscillator power amplifier at 43 MHz.

PubMed

Mörz, Florian; Steinle, Tobias; Steinmann, Andy; Giessen, Harald

2015-09-07

We present a high repetition rate mid-infrared optical parametric master oscillator power amplifier (MOPA) scheme, which is tunable from 1370 to 4120nm. Up to 4.3W average output power are generated at 1370nm, corresponding to a photon conversion efficiency of 78%. Bandwidths of 6 to 12nm with pulse durations between 250 and 400fs have been measured. Strong conversion saturation over the whole signal range is observed, resulting in excellent power stability. The system consists of a fiber-feedback optical parametric oscillator that seeds an optical parametric power amplifier. Both systems are pumped by the same Yb:KGW femtosecond oscillator.

Mid-infrared source with 0.2 J pulse energy based on nonlinear conversion of Q-switched pulses in ZnGeP2.

PubMed

Haakestad, Magnus W; Fonnum, Helge; Lippert, Espen

2014-04-07

Mid-infrared (3-5 μm) pulses with high energy are produced using nonlinear conversion in a ZnGeP(2)-based master oscillator-power amplifier, pumped by a Q-switched cryogenic Ho:YLF oscillator. The master oscillator is based on an optical parametric oscillator with a V-shaped 3-mirror ring resonator, and the power amplifier is based on optical parametric amplification in large-aperture ZnGeP(2) crystals. Pulses with up to 212 mJ energy at 1 Hz repetition rate are obtained, with FWHM duration 15 ns and beam quality M(2) = 3.

Analysis of boron dilution in a four-loop PWR

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

Sun, J.G.; Sha, W.T.

1995-03-01

Thermal mixing and boron dilution in a pressurized water reactor were analyzed with COMMIX codes. The reactor system was the four-loop Zion reactor. Two boron dilution scenarios were analyzed. In the first scenario, the plant is in cold shutdown and the reactor coolant system has just been filled after maintenance on the steam generators. To flush the air out of the steam generator tubes, a reactor coolant pump (RCP) is started, with the water in the pump suction line devoid of boron and at the same temperature as the coolant in the system. In the second scenario, the plant ismore » at hot standby and the reactor coolant system has been heated to operating temperature after a long outage. It is assumed that an RCP is started, with the pump suction line filled with cold unborated water, forcing a slug of diluted coolant down the downcomer and subsequently through the reactor core. The subsequent transient thermal mixing and boron dilution that would occur in the reactor system is simulated for these two scenarios. The reactivity insertion rate and the total reactivity are evaluated and a sensitivity study is performed to assess the accuracy of the numerical modeling of the geometry of the reactor coolant system.« less

Vibration Test of a SNAP-8 Sodium-Potassium Alloy Pump

NASA Image and Video Library

1970-01-21

Aeronautics and Space Administration (NASA) Lewis Research Center. Aerojet General was contracted to design the SNAP-8 generator which employed a mercury Rankine system to convert the reactor’s heat into electrical power. The hermetically-sealed pump was designed to generate from 35 to 90 kilowatts of electrical power. In 1964 a SNAP-8 test rig with a mercury boiler and condenser was set up in cell W-1 of Lewis’ Engine Research Building to study the transients in the system’s three loops. In 1967 a complete Rankine system was operated for 60 days in W-1 to verify the integrity of the Lewis-developed mercury boiler. Further tests in 1969 verified the shutdown and startup of the system under normal and emergency conditions. Aerojet operated the first full-Rankine system in June 1966 and completed a 2500-hour endurance test in early 1969. Lewis and Aerojet’s success on the Rankine system was acknowledged with NASA Group Achievement Award in November 1970. The 1970 vibration tests, seen here, were conducted in Lewis’ Engine Research Building’s environmental laboratory. The testing replicated the shock and vibration expected to occur during the launch into space and subsequent maneuvering. The pump was analyzed on each of its major axes.

JEN-1 Reactor Control System; SISTEMA DE CONTROL DEL REACTOR JEN-1

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

Cantillo, M.F.; Nuno, C.M.; Andreu, J.L.M.

1963-01-01

ABS>The JEN-1 3Mw power swimming pool reactor electrical control circuits are described. Start-up, power generation in the core, and shutdown are controlled by the reactor control system. This control system guarantees in each moment the safety conditions during reactor operation. Each circuit was represented by a scheme, complemented with a description of its function, components, and operation theory. Components described include: scram circuit; fission counter control circuit; servo control circuit; control circuit of safety sheets; control circuits of primary, secondary, and clean-up pump motors and tower fan motor; primary valve motor circuit; center cubicle alarm circuit; and process alarm circuit.more » (auth)« less

40 CFR 63.1111 - Startup, shutdown, and malfunction.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures for...

40 CFR 63.1111 - Startup, shutdown, and malfunction.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures for...

40 CFR 63.1111 - Startup, shutdown, and malfunction.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures for...

40 CFR 63.1111 - Startup, shutdown, and malfunction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures for...

Direct solar-pumped iodine laser amplifier

NASA Technical Reports Server (NTRS)

Han, Kwang S.; Hwang, In Heon; Kim, Khong Hon; Stock, Larry V.

1988-01-01

A XeCl laser pumped iodine laser oscillator was developed which will be incorporated into the Master Oscillator Power Amplifier (MOPA) system. The developed XeCl laser produces output energy of about 60 mJ per pulse. The pulse duration was about 10 nsec. The kinetic model for the solar-pumped laser was refined and the algorithm for the calculation of a set of rate equations was improved to increase the accuracy and the efficiency of the calculation. The improved algorithm was applied to explain the existing experimental data taken from a flashlamp pumped iodine laser for three kinds of lasants, i-C3F7I, n-C4F9I, and t-C4F9I. Various solid laser materials were evaluated for solar-pumping. The materials studied were Nd:YAG, Nd:YLF, and Cr:Nd:GSGG crystals. The slope efficiency of 0.17 percent was measured for the Nd:YLF near the threshold pump intensity which was 211 solar constants (29W/sq cm). The threshold pump intensity of the Nd:YAG was measured to be 236 solar constants (32W/sq cm) and the near-threshold slope efficiency was 0.12 percent. True CW laser operation of Cr:Nd:GSGG was possible only at pump intensities less than or equal to 1,500 solar constants (203 W/sq cm). This fact was attributed to the high thermal focusing effect of the Cr:Nd:GSGG rod.

20 W continuous-wave cladding-pumped Nd-doped fiber laser at 910 nm.

PubMed

Laroche, M; Cadier, B; Gilles, H; Girard, S; Lablonde, L; Robin, T

2013-08-15

We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser emission on the three-level scheme is enabled by the combination of a small inner cladding-to-core diameter ratio and a high brightness pump source at 808 nm. A laser conversion efficiency as high as 44% was achieved in CW operating regime by using resonant fiber Bragg reflectors at 910 nm that prevent the lasing at the 1060 nm competing wavelength. Furthermore, in a master oscillator power-amplifier scheme, an amplified power of 14.8 W was achieved at 914 nm in the same fiber.

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

Success in Introductory Calculus: The Role of High School and Pre-Calculus Preparation

ERIC Educational Resources Information Center

Ayebo, Abraham; Ukkelberg, Sarah; Assuah, Charles

2017-01-01

Calculus at the college level has significant potential to serve as a pump for increasing the number of students majoring in STEM fields. It is a foundation course for all STEM majors and, if mastered well, should provide students with a positive and successful first-year experience and gateway into more advanced courses. Studies have shown that a…

Elemental Scanning Devices Authenticate Works of Art

NASA Technical Reports Server (NTRS)

2013-01-01

To better detect aluminum compounds, Marshall Space Flight Center partnered with KeyMaster Inc. (later acquired by Madison, Wisconsin-based Bruker AXS Inc.) to develop a vacuum pump system that could be attached to X-ray fluorescence (XRF) scanners. The resulting technology greatly expanded XRF scanner capabilities, and hundreds of museums now use them to authenticate artifacts and works of art.

Overview of ground coupled heat pump research and technology transfer activities

NASA Astrophysics Data System (ADS)

Baxter, V. D.; Mei, V. C.

Highlights of DOE-sponsored ground coupled heat pump (GCHP) research at Oak Ridge National Laboratory (ORNL) are presented. ORNL, in cooperation with Niagara Mohawk Power Company, Climate Master, Inc., and Brookhaven National Laboratory developed and demonstrated an advanced GCHP design concept with shorter ground coils that can reduce installed costs for northern climates. In these areas it can also enhance the competitiveness of GCHP systems versus air-source heat pumps by lowering their payback from 6 to 7 years to 3 to 5 years. Ground coil heat exchanger models (based primarily on first principles) have been developed and used by others to generate less conservative ground coil sizing methods. An aggressive technology transfer initiative was undertaken to publicize results of this research and make it available to the industry. Included in this effort were an international workshop, trade press releases and articles, and participation in a live teleconference on GCHP technology.

Thermal modeling of a cryogenic turbopump for space shuttle applications.

NASA Technical Reports Server (NTRS)

Knowles, P. J.

1971-01-01

Thermal modeling of a cryogenic pump and a hot-gas turbine in a turbopump assembly proposed for the Space Shuttle is described in this paper. A model, developed by identifying the heat-transfer regimes and incorporating their dependencies into a turbopump system model, included heat transfer for two-phase cryogen, hot-gas (200 R) impingement on turbine blades, gas impingement on rotating disks and parallel plate fluid flow. The ?thermal analyzer' program employed to develop this model was the TRW Systems Improved Numerical Differencing Analyzer (SINDA). This program uses finite differencing with lumped parameter representation for each node. Also discussed are model development, simulations of turbopump startup/shutdown operations, and the effects of varying turbopump parameters on the thermal performance.

High energy 523 nm ND:YLF pulsed slab laser with novel pump beam waveguide design

NASA Astrophysics Data System (ADS)

Yang, Qi; Zhu, Xiaolei; Ma, Jian; Lu, Tingting; Ma, Xiuhua; Chen, Weibiao

2015-11-01

A laser diode pumped Nd:YLF master oscillator power amplifier (MOPA) green laser system with high pulse energy and high stable output is demonstrated. At a repetition rate of 50 Hz, 840 mJ pulse energy, 9.1 ns pulse width of 1047 nm infrared laser emitting is obtained from the MOPA system. The corresponding peak power is 93 MW. Extra-cavity frequency doubling with a LiB3O5 crystal, pulse energy of 520 mJ at 523 nm wavelength is achieved. The frequency conversion efficiency reaches up to 62%. The output pulse energy instability of the laser system is less than 0.6% for one hour.

Narrowband, tunable, 2 µm optical parametric master-oscillator power amplifier with large-aperture periodically poled Rb:KTP

NASA Astrophysics Data System (ADS)

Coetzee, R. S.; Zheng, X.; Fregnani, L.; Laurell, F.; Pasiskevicius, V.

2018-06-01

A high-energy, ns, narrow-linewidth optical parametric oscillator and amplifier system based on large-aperture periodically poled Rb:KTP is presented. The 2 µm seed source is a singly resonant OPO locked with a transversely chirped volume Bragg grating, allowing a wavelength tuning of 21 nm and output linewidth of 0.56 nm. A maximum output energy of 52 mJ and conversion efficiency of 36% was obtained from the amplifier for a pump energy of 140 mJ. The high-energy and the robust and narrow dual-wavelength spectra obtained make this system an ideal pump source for difference frequency generation-based THz generation schemes.

40 CFR 63.1111 - Startup, shutdown, and malfunction.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction. 63.1111 Section 63.1111 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and...

40-fs hydrogen Raman laser

NASA Astrophysics Data System (ADS)

Didenko, N. V.; Konyashchenko, A. V.; Kostryukov, P. V.; Losev, L. L.; Pazyuk, V. S.; Tenyakov, S. Yu; Molchanov, V. Ya; Chizhikov, S. I.; Yushkov, K. B.

2015-12-01

40-fs first Stokes pulses at a wavelength of 1.2 μm were generated in a hydrogen SRS-converter pumped by orthogonally polarised double chirped pulses of a Ti : sapphire laser. To obtain a Stokes pulse close to a transform-limited one, a programmed acousto-optic dispersive delay line was placed between the master oscillator and regenerative amplifier. The energy efficiency of Stokes radiation conversion reached 22%.

Bipolar square-wave current source for transient electromagnetic systems based on constant shutdown time

NASA Astrophysics Data System (ADS)

Wang, Shilong; Yin, Changchun; Lin, Jun; Yang, Yu; Hu, Xueyan

2016-03-01

Cooperative work of multiple magnetic transmitting sources is a new trend in the development of transient electromagnetic system. The key is the bipolar current waves shutdown, concurrently in the inductive load. In the past, it was difficult to use the constant clamping voltage technique to realize the synchronized shutdown of currents with different peak values. Based on clamping voltage technique, we introduce a new controlling method with constant shutdown time. We use the rising time to control shutdown time and use low voltage power source to control peak current. From the viewpoint of the circuit energy loss, by taking the high-voltage capacitor bypass resistance and the capacitor of the passive snubber circuit into account, we establish the relationship between the rising time and the shutdown time. Since the switch is not ideal, we propose a new method to test the shutdown time by the low voltage, the high voltage and the peak current. Experimental results show that adjustment of the current rising time can precisely control the value of the clamp voltage. When the rising time is fixed, the shutdown time is unchanged. The error for shutdown time deduced from the energy consumption is less than 6%. The new controlling method on current shutdown proposed in this paper can be used in the cooperative work of borehole and ground transmitting system.

Bipolar square-wave current source for transient electromagnetic systems based on constant shutdown time.

PubMed

Wang, Shilong; Yin, Changchun; Lin, Jun; Yang, Yu; Hu, Xueyan

2016-03-01

Cooperative work of multiple magnetic transmitting sources is a new trend in the development of transient electromagnetic system. The key is the bipolar current waves shutdown, concurrently in the inductive load. In the past, it was difficult to use the constant clamping voltage technique to realize the synchronized shutdown of currents with different peak values. Based on clamping voltage technique, we introduce a new controlling method with constant shutdown time. We use the rising time to control shutdown time and use low voltage power source to control peak current. From the viewpoint of the circuit energy loss, by taking the high-voltage capacitor bypass resistance and the capacitor of the passive snubber circuit into account, we establish the relationship between the rising time and the shutdown time. Since the switch is not ideal, we propose a new method to test the shutdown time by the low voltage, the high voltage and the peak current. Experimental results show that adjustment of the current rising time can precisely control the value of the clamp voltage. When the rising time is fixed, the shutdown time is unchanged. The error for shutdown time deduced from the energy consumption is less than 6%. The new controlling method on current shutdown proposed in this paper can be used in the cooperative work of borehole and ground transmitting system.

Development of lasers optimized for pumping Ti:Al2O3 lasers

NASA Technical Reports Server (NTRS)

Rines, Glen A.; Schwarz, Richard A.

1994-01-01

Laboratory demonstrations that were completed included: (1) an all-solid-state, broadly tunable, single-frequency, Ti:Al2O3 master oscillator, and (2) a technique for obtaining 'long' (nominally 100- to 200-ns FWHM) laser pulses from a Q-switched, Nd oscillator at energy levels commensurate with straightforward amplification to the joule level. A diode-laser-pumped, Nd:YLF laser with intracavity SHG was designed, constructed, and evaluated. With this laser greater than 0.9 W of CW, output power at 523.5 nm with 10 W of diode-laser pump power delivered to the Nd:YLF crystal was obtained. With this laser as a pump source, for the first time, to our knowledge, an all solid-state, single frequency, Ti:Al203 laser with sufficient output power to injection seed a high-energy oscillator over a 20-nm bandwidth was demonstrated. The pulsed laser work succeeded in demonstrating pulse-stretching in a Q-switched Nd:YAG oscillator. Pulse energies greater than 50-mJ were obtained in pulses with 100- to 200-ns pulsewidths (FWHM).

40 CFR 63.762 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.762 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of non...

40 CFR 63.762 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.762 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of non...

40 CFR 63.1272 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.1272 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of...

40 CFR 63.1272 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Startups, shutdowns, and malfunctions... Facilities § 63.1272 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of...

40 CFR 63.762 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.762 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of non...

40 CFR 63.1272 - Startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Startups, shutdowns, and malfunctions... Facilities § 63.1272 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of...

Reactor shutdown experience

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

Cletcher, J.W.

1995-10-01

This is a regular report of summary statistics relating to recent reactor shutdown experience. The information includes both number of events and rates of occurence. It was compiled from data about operating events that were entered into the SCSS data system by the Nuclear Operations Analysis Center at the Oak ridge National Laboratory and covers the six mont period of July 1 to December 31, 1994. Cumulative information, starting from May 1, 1994, is also reported. Updates on shutdown events included in earlier reports is excluded. Information on shutdowns as a function of reactor power at the time of themore » shutdown for both BWR and PWR reactors is given. Data is also discerned by shutdown type and reactor age.« less

40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

40 CFR Table 1 to Subpart Aaaa of... - Applicability of NESHAP General Provisions to Subpart AAAA

Code of Federal Regulations, 2012 CFR

2012-07-01

... constructed, and reconstructed sources 63.6(e) Operation and maintenance requirements, startup, shutdown and... taken during a startup, shutdown and malfunction plan are consistent with the procedures in the startup, shutdown and malfunction plan, this information shall be included in a semi-annual startup, shutdown and...

40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR Table 1 to Subpart Aaaa of... - Applicability of NESHAP General Provisions to Subpart AAAA

Code of Federal Regulations, 2014 CFR

2014-07-01

... constructed, and reconstructed sources 63.6(e) Operation and maintenance requirements, startup, shutdown and... taken during a startup, shutdown and malfunction plan are consistent with the procedures in the startup, shutdown and malfunction plan, this information shall be included in a semi-annual startup, shutdown and...

40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR Table 1 to Subpart Aaaa of... - Applicability of NESHAP General Provisions to Subpart AAAA

Code of Federal Regulations, 2013 CFR

2013-07-01

... constructed, and reconstructed sources 63.6(e) Operation and maintenance requirements, startup, shutdown and... taken during a startup, shutdown and malfunction plan are consistent with the procedures in the startup, shutdown and malfunction plan, this information shall be included in a semi-annual startup, shutdown and...

40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

Characterization of On-Orbit U.S. Lab Condensate Vacuum Venting

NASA Astrophysics Data System (ADS)

Schmidl, W. D.; Alred, J. A.; Mikatarian, R.; Soares, C.; Miles, E.

2002-01-01

The venting of liquid streams into a vacuum has been studied extensively for many years. An experiment was performed aboard the International Space Station (ISS) to video tape the U.S. Lab's condensate venting event with cameras located on the Space Station Remote Manipulator System (SSRMS). Images of the vent plume were acquired close to both the port and starboard vent nozzles. The imaging started with a wider view and then zoomed in closer before the shutdown phase of the vent event occurred. The objective of this experiment was to extend our understanding of the properties of venting liquids into space. Data from the video images were analyzed to obtain the approximate cone angle encompassing the core of the vent plume. The condensate vent plume was characterized as having three phases, a startup phase, a nominal phase, and a shutdown phase. The startup phase consisted of the initial period when the vent first started and the liquid first entered the heated line. The nominal phase was the period when the majority of the liquid was vented. The shutdown phase occurs close to the end of the vent event. The shutdown phase was further divided into two parts, the shutdown initial phase, and a later shutdown sputtering phase. The shutdown initial phase occurs when gas becomes entrained in the condensate liquid being vented. The sputtering phase occurred after the vent valve was closed, and the liquid/ice in the line was removed by continuing to heat the line to bake it out. It was determined that the ice particles were ejected at higher angles, but lower velocities, during the startup and shutdown phases. The number and velocities of ice particles ejected outside of the core region, during the startup, initial shutdown and shutdown sputtering phases were determined. The core of liquid ejected during the startup and shutdown phases was contained within a half cone angle of less than 60 degrees. The startup phase took approximately 36 seconds, the shutdown initial phase took approximately 22 seconds, and the shutdown sputtering phase took approximately 32 seconds. Results from the experiment were correlated with the Boeing ISS vent plume model.

The Importance of Engine External's Health

NASA Technical Reports Server (NTRS)

Stoner, Barry L.

2006-01-01

Engine external components include all the fluid carrying, electron carrying, and support devices that are needed to operate the propulsion system. These components are varied and include: pumps, valves, actuators, solenoids, sensors, switches, heat exchangers, electrical generators, electrical harnesses, tubes, ducts, clamps and brackets. The failure of any component to perform its intended function will result in a maintenance action, a dispatch delay, or an engine in flight shutdown. The life of each component, in addition to its basic functional design, is closely tied to its thermal and dynamic environment .Therefore, to reach a mature design life, the component's thermal and dynamic environment must be understood and controlled, which can only be accomplished by attention to design analysis and testing. The purpose of this paper is to review analysis and test techniques toward achieving good component health.

Record power, ultra-broadband supercontinuum source based on highly GeO₂ doped silica fiber.

PubMed

Jain, D; Sidharthan, R; Moselund, P M; Yoo, S; Ho, D; Bang, O

2016-11-14

We demonstrate highly germania doped fibers for mid-infrared supercontinuum generation. Experiments ensure a highest output power of 1.44 W for a broadest spectrum from 700 nm to 3200 nm and 6.4 W for 800 nm to 2700 nm from these fibers, while being pumped by a broadband Erbium-Ytterbium doped fiber based master oscillator power amplifier. The effect of repetition frequency of pump source and length of germania-doped fiber has also been investigated. Further, germania doped fiber has been pumped by conventional supercontinuum source based on silica photonic crystal fiber supercontinuum source. At low power, a considerable broadening of 200-300 nm was observed. Further broadening of spectrum was limited due to limited power of pump source. Our investigations reveal the unexploited potential of germania doped fiber for mid-infrared supercontinuum generation. These measurements ensure the potential of germania based photonic crystal fiber or a step-index fiber supercontinuum source for high power ultra-broad band emission being by pumped a 1060 nm or a 1550 nm laser source. To the best of our knowledge, this is the record power, ultra-broadband, and all-fiberized supercontinuum light source based on silica and germania fiber ever demonstrated to the date.

Simulated flow of groundwater and brine from a flooded salt mine in Livingston County, New York, and effects of remedial pumping on an overlying aquifer

USGS Publications Warehouse

Yager, Richard M.; Miller, Todd S.; Kappel, William M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.; deVries, M. Peter

2012-01-01

Two ceiling collapses in the Retsof salt mine near Geneseo in upstate New York in spring 1994 resulted in the upward propagation of two columns of rubble through 600 feet of overlying shale and carbonate bedrock. This upward propagation formed a hydraulic connection between the lower confined aquifer (LCA) and the mine and allowed water from the aquifer and bedrock fracture zones that intersected the rubble columns to flow into the mine at a rate of 18,000 gallons per minute (gal/min) . All salt mining ceased in September 1995, and the mine was completely flooded by January 1996. The flow of water from the lower confined aquifer into the mine caused widespread drawdowns, and water levels in the aquifer declined by as much as 400 feet near the collapse area and by more than 50 feet at wells 7 miles to the north and south. Within 3 to 4 weeks of the collapses, water levels in about a dozen domestic and industrial wells had declined severely, and some wells went dry. Water levels in at least 58 wells in the lower and middle confined aquifers were affected by mine flooding. Groundwater in the upper unconfined aquifer and surface water in streams were unaffected by water-level drawdown, but channels of the Genesee River and Beards Creek were altered by land subsidence related to the mine collapse. Water levels recovered from 1996 through 2006, but the mine is now filled with about 15 billion gallons of saturated halite brine. The weight of the overlying rock and sediment is expected to cause the salt beds to deform and fill the mine cavity during the next several hundred years; this in turn could displace as much as 80 percent of the brine and cause it to move upward through the rubble chimneys, rendering the LCA unusable as a source of water supply. Saline water was detected in the LCA in 2002 but was found to be derived primarily from fractures in the limestone and shale units between the mine and the LCA, rather than from the mine. In September 2006, the mine company began a brine-mitigation project that entailed pumping five wells finished in limestone and shale units within the collapse areas to alter the flow gradient and thereby prevent further movement of brine and saline water into the LCA. The pumped brine was routed to an onsite desalination plant. At the same time, the U.S. Geological Survey (USGS) began a study in cooperation with the New York State Office of the Attorney General to construct numerical models to analyze the groundwater chemistry and delineate the directions of flow. Specific objectives of the study were to: * Assess the sources of salinity within the collapse area and identify the factors that control the movement and mixing of freshwater, saline waters from fracture zones, and brine; * Evaluate the likelihood that the pumping will induce anhydrite dissolution and lead to continued land subsidence; * Construct variable-density groundwater flow models to predict the effect of remedial pumping on salinity within the LCA; * Evaluate the effectiveness of remedial pumping in preventing the movement of saline water into the LCA; and * Predict the extent of brine migration 8 years after a hypothetical shutdown of all pumping in 2008. This report (1) summarizes the hydrogeologic setting and effects of mine flooding, (2) describes the geochemical and variable-density model simulations and their principal results, (3) discusses the implications of (a) continued pumping and desalination to protect the LCA and (b) a full shutdown of pumping after 2008, and (4) suggests further research that could lead to refinement of model predictions. Additional information may be found in Yager and others (2001 and 2009). These reports can be accessed at http://pubs.usgs.gov/pp/pp1611/ and http://pubs.usgs.gov/pp/pp1767/, respectively. A summary of simulation results can be accessed at http://ny.water.usgs.gov/projects/Coram/seawat/seawat.html.

2.36 J, 50 Hz nanosecond pulses from a diode side-pumped Nd:YAG MOPA system

NASA Astrophysics Data System (ADS)

Li, Chaoyang; Lu, Chengqiang; Li, Chuan; Yang, Ning; Li, Ye; Yang, Zhen; Han, Song; Shi, Junfeng; Zhou, Zewu

2017-07-01

We report on a high-energy high-repetition-rate nanosecond Nd:YAG main oscillator power amplifier (MOPA) system. Maximum output pulse energy of 2.36 J with duration of 9.4 ns at 50 Hz has been achieved. The master oscillator was a LD side-pumped electro-optical Q-switched Nd:YAG rod laser adopting unstable cavity with variable reflectivity mirror (VRM). It delivered a pulse train with energy up to 180 mJ and pulse duration of 10.7 ns. The near-field pattern demonstrated a nearly super Gaussian flat top profile. In the amplification stage, the pulse was boosted via double-pass two Nd:YAG rod amplifiers. Maximum pulse energy was obtained at the peak pump power of 37.5 kW, corresponding to an optical-optical conversion efficiency of 25.2%. The correlative peak power was deduced to be 251 MW. We also presented the result of 100 Hz nanosecond laser with average output power of >100 W.

Dissipative preparation of steady Greenberger-Horne-Zeilinger states for Rydberg atoms with quantum Zeno dynamics

NASA Astrophysics Data System (ADS)

Shao, X. Q.; Wu, J. H.; Yi, X. X.; Long, Gui-Lu

2017-12-01

Inspired by a recent work [F. Reiter, D. Reeb, and A. S. Sørensen, Phys. Rev. Lett. 117, 040501 (2016), 10.1103/PhysRevLett.117.040501], we present a simplified proposal for dissipatively preparing a Greenberger-Horne-Zeilinger (GHZ) state of three Rydberg atoms in a cavity. The Z pumping is implemented under the action of the spontaneous emission of Λ -type atoms and the quantum Zeno dynamics induced by strong continuous coupling. In the meantime, a dissipative Rydberg pumping breaks up the stability of the state | GHZ+〉 in the process of Z pumping, making | GHZ-〉 the unique steady state of the system. Compared with the former scheme, the number of driving fields acting on atoms is greatly reduced and only a single-mode cavity is required. The numerical simulation of the full master equation reveals that a high fidelity ˜98 % can be obtained with the currently achievable parameters in the Rydberg-atom-cavity system.

Defense.gov Special Report: Government Shutdown

Science.gov Websites

reached. Government shutdown avoided. Business as usual for all DOD employees. Deal Averts Shutdown Continuing Resolution (PDF) Deputy Secretary Lynn Message OMB Director Memo to Agencies (PDF) DOD Contingency

Numerical simulation of incoherent optical wave propagation in nonlinear fibers

NASA Astrophysics Data System (ADS)

Fernandez, Arnaud; Balac, Stéphane; Mugnier, Alain; Mahé, Fabrice; Texier-Picard, Rozenn; Chartier, Thierry; Pureur, David

2013-11-01

The present work concerns the study of pulsed laser systems containing a fiber amplifier for boosting optical output power. In this paper, this fiber amplification device is included into a MOPFA laser, a master oscillator coupled with fiber amplifier, usually a cladding-pumped high-power amplifier often based on an ytterbium-doped fiber. An experimental study has established that the observed nonlinear effects (such as Kerr effect, four waves mixing, Raman effect) could behave very differently depending on the characteristics of the optical source emitted by the master laser. However, it has not yet been possible to determine from the experimental data if the statistics of the photons is alone responsible for the various nonlinear scenarios observed. Therefore, we have developed a numerical simulation software for solving the generalized nonlinear Schrödinger equation with a stochastic source term in order to validate the hypothesis that the coherence properties of the master laser are mainly liable for the behavior of the observed nonlinear effects. Contribution to the Topical Issue "Numelec 2012", Edited by Adel Razek.

46 CFR 111.33-7 - Alarms and shutdowns.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor rectifier must have a high temperature alarm or shutdown, except as provided in § 111.33-11. ...

Standardization of Hull, Mechanical, and Electrical Equipment (H,M&E) inventory

DTIC Science & Technology

1987-09-01

Miami University, 1974 M.B.A., George Washington University, 1985 Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...Motors, Pumps, and Controllers) within the Weapon System 84 Interview with Messrs. George Blackmore, and William Bunge, Equipment Specialist, SPCC, May 18... George Blackmore, and William Bunge, SPCC, May 18, 1987. 52 V. S identical equipment. The reduction in the equipment range increased the volume for

High Efficiency End-Pumped Ho:Tm:YLF Disk Amplifier

NASA Technical Reports Server (NTRS)

Yu, Jirong; Singh, Upendra N.; Petros, Mulugeta; Axenson, Theresa J.; Barnes, Norman P.

1999-01-01

Space based coherent lidar for global wind measurement requires an all solid state laser system with high energy, high efficiency and narrow linewidth that operates in the eye safe region. A Q-switched, diode pumped Ho:Tm:YLF 2 micrometer laser with output energy of as much as 125 mJ at 6 Hz with an optical-to-optical efficiency of 3% has been reported. Single frequency operation of the laser was achieved by injection seeding. The design of this laser is being incorporated into NASA's SPARCLE (SPAce Readiness Coherent Lidar Experiment) wind lidar mission. Laser output energy ranging from 500 mJ to 2 J is required for an operational space coherent lidar. We previously developed a high energy Ho:Tm:YLF master oscillator and side pumped power amplifier system and demonstrated a 600-mJ single frequency pulse at a repetition rate of 10 Hz. Although the output energy is high, the optical-to-optical efficiency is only about 2%. Designing a high energy, highly efficient, conductively cooled 2-micrometer laser remains a challenge. In this paper, the preliminary result of an end-pumped amplifier that has a potential to provide a factor 3 of improvement in the system efficiency is reported.

High power pulsed sources based on fiber amplifiers

NASA Astrophysics Data System (ADS)

Canat, Guillaume; Jaouën, Yves; Mollier, Jean-Claude; Bouzinac, Jean-Pierre; Cariou, Jean-Pierre

2017-11-01

Cladding-pumped rare-earth-doped fiber laser technologies are currently among the best sources for high power applications. Theses extremely compact and robust sources appoint them as good candidate for aeronautical and space applications. The double-clad (DC) fiber converts the poor beamquality of high-power large-area pump diodes from the 1st cladding to laser light at another wavelength guided in an active single-mode core. High-power coherent MOPA (Master Oscillator Power Amplifier) sources (several 10W CW or several 100W in pulsed regime) will soon be achieved. Unfortunately it also brings nonlinear effects which quickly impairs output signal distortions. Stimulated Brillouin scattering (SBS) and optical parametric amplification (OPA) have been shown to be strong limitations. Based on amplifier modeling and experiments we discuss the performances of these sources.

Two-beam combined 3.36  J, 100  Hz diode-pumped high beam quality Nd:YAG laser system.

PubMed

Qiu, J S; Tang, X X; Fan, Z W; Wang, H C; Liu, H

2016-07-20

In this paper, we develop a diode-pumped all-solid-state high-energy and high beam quality Nd:YAG laser system. A master oscillator power amplifier structure is used to provide a high pulse energy laser output with a high repetition rate. In order to decrease the amplifier working current so as to reduce the impact of the thermal effect on the beam quality, a beam splitting-amplifying-combining scheme is adopted. The energy extraction efficiency of the laser system is 50.68%. We achieve 3.36 J pulse energy at a 100 Hz repetition rate with a pulse duration of 7.1 ns, a far-field beam spot 1.71 times the diffraction limit, and 1.07% energy stability (RMS).

Progress in Electron Beam Mastering of 100 Gbit/inch2 Density Disc

NASA Astrophysics Data System (ADS)

Takeda, Minoru; Furuki, Motohiro; Yamamoto, Masanobu; Shinoda, Masataka; Saito, Kimihiro; Aki, Yuichi; Kawase, Hiroshi; Koizumi, Mitsuru; Miyokawa, Toshiaki; Mutou, Masao; Handa, Nobuo

2004-07-01

We developed an electron beam recorder (EBR) capable of recording master discs under atmospheric conditions using a novel differential pumping head. Using the EBR and optimized fabrication process for Si-etched discs with reactive ion etching (RIE), a bottom signal jitter of 9.6% was obtained from a 36 Gbit/inch2 density disc, readout using a near-field optical pickup with an effective numerical aperture (NA) of 1.85 and a wavelength of 405 nm. We also obtained the eye patterns from a 70 Gbit/inch2 density disc readout using an optical pickup with a 2.05 NA and the same wavelength, and showed almost the same modulation ratio as the simulation value. Moreover, the capability of producing pit patterns corresponding to a 104 Gbit/inch2 density is demonstrated.

The 2013 US Government Shutdown (#Shutdown) and health: an emerging role for social media.

PubMed

Merchant, Raina M; Ha, Yoonhee P; Wong, Charlene A; Schwartz, H Andrew; Sap, Maarten; Ungar, Lyle H; Asch, David A

2014-12-01

In October 2013, multiple United States (US) federal health departments and agencies posted on Twitter, "We're sorry, but we will not be tweeting or responding to @replies during the shutdown. We'll be back as soon as possible!" These "last tweets" and the millions of responses they generated revealed social media's role as a forum for sharing and discussing information rapidly. Social media are now among the few dominant communication channels used today. We used social media to characterize the public discourse and sentiment about the shutdown. The 2013 shutdown represented an opportunity to explore the role social media might play in events that could affect health.

All solid-state diode pumped Nd:YAG MOPA with stimulated Brillouin phase conjugate mirror

NASA Astrophysics Data System (ADS)

Offerhaus, H. L.; Godfried, H. P.; Witteman, W. J.

1996-02-01

At the Nederlands Centrum voor Laser Research (NCLR) a 1 kHz diode-pumped Nd:YAG Master Oscillator Power Amplifier (MOPA) chain with a Stimulated Brillouin Scattering (SBS) Phase Conjugate mirror is designed and operated. A small Brewster angle Nd:YAG slab (2 by 2 by 20 mm) is side pumped with 200 μs diode pulses in a stable oscillator. The oscillator is Q-switched and injection seeded with a commercial diode pumped single frequency CW Nd:YAG laser. The output consists of single-transverse, single-longitudinal mode 25 ns FWHM-pulses at 1064 nm. The oscillator slab is imaged on a square aperture that transmits between 3 and 2 mJ (at 100 and 400 Hz, resp.) The aperture is subsequently imaged four times in the amplifier. The amplifier is a 3 by 6 by 60 mm Brewster angle zig-zag slab, pumped by an 80-bar diode stack with pulses up to 250 μs. After the second pass the light is focused in two consecutive cells containing Freon-113 for wave-front reversal in an oscillator/amplifier-setup with a reflectivity of 60%. The light then passes through the amplifier twice more to produce 20 W (at 400 Hz) of output with near diffraction limited beam quality. To increase the output to 50 W at 1 kHz thermal lensing in the oscillator will be reduced.

Fiber Optical Parametric Oscillator for High Power, High Efficiency Short-Wavelength Generation

DTIC Science & Technology

2010-12-05

the spectral region about 1550 nm, this project has explored the possibility of using ytterbium - doped fiber lasers (YDFL) and amplifiers (YDFA) as...integration. From this point of view, an ytterbium - doped fiber -based pump source looks most attractive. Of particular interest is the master- oscillator... ytterbium - doped fiber amplifiers (YDFA). The MOPA constructed for this work is shown in Figure 1. It consists of a CW fiber ring-laser centered at

40 CFR 63.1354 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... operator during a startup, shutdown, or malfunction of an affected source (including actions taken to correct a malfunction) are consistent with the procedures specified in the source's startup, shutdown, and... report. Reports shall only be required if a startup, shutdown, or malfunction occurred during the...

The 2013 US Government Shutdown (#Shutdown) and Health: An Emerging Role for Social Media

PubMed Central

Ha, Yoonhee P.; Wong, Charlene A.; Schwartz, H. Andrew; Sap, Maarten; Ungar, Lyle H.; Asch, David A.

2014-01-01

In October 2013, multiple United States (US) federal health departments and agencies posted on Twitter, “We’re sorry, but we will not be tweeting or responding to @replies during the shutdown. We’ll be back as soon as possible!” These “last tweets” and the millions of responses they generated revealed social media’s role as a forum for sharing and discussing information rapidly. Social media are now among the few dominant communication channels used today. We used social media to characterize the public discourse and sentiment about the shutdown. The 2013 shutdown represented an opportunity to explore the role social media might play in events that could affect health. PMID:25322303

A flexible master oscillator for a pulse-burst laser system

NASA Astrophysics Data System (ADS)

Den Hartog, D. J.; Young, W. C.

2015-12-01

A new master oscillator is being installed in the pulse-burst laser system used for high-rep-rate Thomson scattering on the MST experiment. This new master oscillator will enable pulse repetition rates up to 1 MHz, with the ability to program a burst of pulses with arbitrary and varying time separation between each pulse. In addition, the energy of each master oscillator pulse can be adjusted to compensate for gain variations in the power amplifier section of the laser system. This flexibility is accomplished by chopping a CW laser source with a high-bandwidth acousto-optic modulator (AOM). The laser source is a Laser Quantum ventus 1064 diode-pumped solid-state laser with continuous output power variable from 100 to 500 mW. The 1064 nm, 2.7 mm diameter polarized beam is focused into the gallium phosphide crystal of a Brimrose AOM, which deflects the beam by approximately 60 mR when driven by the 400 MHz fixed frequency driver. Beam deflection is controlled by a simple digital input pulse, and is capable of producing deflected pulses of less than 20 ns width at repetition rates much greater than 1 MHz. These deflected pulses from the output of the AOM are collimated and propagated into the laser amplifier system, where they will be amplified to ~ 2 J/pulse and injected into the MST plasma.

40 CFR 68.52 - Operating procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Initial startup; (2) Normal operations; (3) Temporary operations; (4) Emergency shutdown and operations; (5) Normal shutdown; (6) Startup following a normal or emergency shutdown or a major change that... are updated, if necessary, whenever a major change occurs and prior to startup of the changed process. ...

40 CFR 68.52 - Operating procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Initial startup; (2) Normal operations; (3) Temporary operations; (4) Emergency shutdown and operations; (5) Normal shutdown; (6) Startup following a normal or emergency shutdown or a major change that... are updated, if necessary, whenever a major change occurs and prior to startup of the changed process. ...

40 CFR 68.52 - Operating procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Initial startup; (2) Normal operations; (3) Temporary operations; (4) Emergency shutdown and operations; (5) Normal shutdown; (6) Startup following a normal or emergency shutdown or a major change that... are updated, if necessary, whenever a major change occurs and prior to startup of the changed process. ...

40 CFR 68.52 - Operating procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Initial startup; (2) Normal operations; (3) Temporary operations; (4) Emergency shutdown and operations; (5) Normal shutdown; (6) Startup following a normal or emergency shutdown or a major change that... are updated, if necessary, whenever a major change occurs and prior to startup of the changed process. ...

40 CFR 52.1183 - Visibility protection.

Code of Federal Regulations, 2013 CFR

2013-07-01

... excess emissions that occurs during startups, shutdowns, and malfunctions of the unit, the nature and... that occurs during startups, shutdowns, and malfunctions of the unit, the nature and cause of any... startup, shutdown, and malfunction. (viii) All CEMS required by this section must meet the minimum data...

33 CFR 127.1205 - Emergency shutdown.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Hazardous Gas Equipment § 127.1205 Emergency shutdown. (a) Each... elements that melt at less than 105 °C (221 °F) and activate the emergency shutdown, or have a sensor that...

33 CFR 127.1205 - Emergency shutdown.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Hazardous Gas Equipment § 127.1205 Emergency shutdown. (a) Each... elements that melt at less than 105 °C (221 °F) and activate the emergency shutdown, or have a sensor that...

76 FR 81998 - Methodology for Low Power/Shutdown Fire PRA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-29

... NUCLEAR REGULATORY COMMISSION [NRC-2011-0295] Methodology for Low Power/Shutdown Fire PRA AGENCY..., ``Methodology for Low Power/Shutdown Fire PRA--Draft Report for Comment.'' DATES: Submit comments by March 01... risk assessment (PRA) method for quantitatively analyzing fire risk in commercial nuclear power plants...

40 CFR 63.1164 - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... written extension of compliance. (c) Periodic startup, shutdown, and malfunction reports. Section 63.6(e... by the standard at all times, including during any period of startup, shutdown, or malfunction...)(3) of subpart A of this part, the owner or operator shall develop a written startup, shutdown, and...

40 CFR 63.2250 - What are the general requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... periods of process unit or control device startup, shutdown, and malfunction; prior to process unit initial startup; and during the routine control device maintenance exemption specified in § 63.2251. The... are not operating, or during periods of startup, shutdown, and malfunction. Startup and shutdown...

40 CFR 63.2250 - What are the general requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... periods of process unit or control device startup, shutdown, and malfunction; prior to process unit initial startup; and during the routine control device maintenance exemption specified in § 63.2251. The... are not operating, or during periods of startup, shutdown, and malfunction. Startup and shutdown...

40 CFR 63.1164 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... written extension of compliance. (c) Periodic startup, shutdown, and malfunction reports. Section 63.6(e... by the standard at all times, including during any period of startup, shutdown, or malfunction...)(3) of subpart A of this part, the owner or operator shall develop a written startup, shutdown, and...

40 CFR 63.1164 - Reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... written extension of compliance. (c) Periodic startup, shutdown, and malfunction reports. Section 63.6(e... by the standard at all times, including during any period of startup, shutdown, or malfunction...)(3) of subpart A of this part, the owner or operator shall develop a written startup, shutdown, and...

40 CFR 270.235 - Options for incinerators, cement kilns, lightweight aggregate kilns, solid fuel boilers, liquid...

Code of Federal Regulations, 2014 CFR

2014-07-01

... to minimize emissions from startup, shutdown, and malfunction events. 270.235 Section 270.235... from startup, shutdown, and malfunction events. (a) Facilities with existing permits—(1) Revisions to... from startup, shutdown, and malfunction events under any of the following options when requesting...

40 CFR 270.235 - Options for incinerators, cement kilns, lightweight aggregate kilns, solid fuel boilers, liquid...

Code of Federal Regulations, 2012 CFR

2012-07-01

... to minimize emissions from startup, shutdown, and malfunction events. 270.235 Section 270.235... from startup, shutdown, and malfunction events. (a) Facilities with existing permits—(1) Revisions to... from startup, shutdown, and malfunction events under any of the following options when requesting...

40 CFR 270.235 - Options for incinerators, cement kilns, lightweight aggregate kilns, solid fuel boilers, liquid...

Code of Federal Regulations, 2011 CFR

2011-07-01

... to minimize emissions from startup, shutdown, and malfunction events. 270.235 Section 270.235... from startup, shutdown, and malfunction events. (a) Facilities with existing permits—(1) Revisions to... from startup, shutdown, and malfunction events under any of the following options when requesting...

40 CFR 270.235 - Options for incinerators, cement kilns, lightweight aggregate kilns, solid fuel boilers, liquid...

Code of Federal Regulations, 2013 CFR

2013-07-01

... to minimize emissions from startup, shutdown, and malfunction events. 270.235 Section 270.235... from startup, shutdown, and malfunction events. (a) Facilities with existing permits—(1) Revisions to... from startup, shutdown, and malfunction events under any of the following options when requesting...

46 CFR 111.33-7 - Alarms and shutdowns.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

46 CFR 111.33-7 - Alarms and shutdowns.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

46 CFR 111.33-7 - Alarms and shutdowns.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

46 CFR 111.33-7 - Alarms and shutdowns.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Malfunction, startup, and shutdown regulations. 52.271 Section 52.271 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.271 Malfunction, startup, and shutdown regulations. (a)...

40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 3 2011-07-01 2011-07-01 false Malfunction, startup, and shutdown regulations. 52.271 Section 52.271 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.271 Malfunction, startup, and shutdown regulations. (a)...

40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 3 2013-07-01 2013-07-01 false Malfunction, startup, and shutdown regulations. 52.271 Section 52.271 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.271 Malfunction, startup, and shutdown regulations. (a)...

40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 3 2012-07-01 2012-07-01 false Malfunction, startup, and shutdown regulations. 52.271 Section 52.271 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.271 Malfunction, startup, and shutdown regulations. (a)...

40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 3 2014-07-01 2014-07-01 false Malfunction, startup, and shutdown regulations. 52.271 Section 52.271 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.271 Malfunction, startup, and shutdown regulations. (a)...

77 FR 10576 - Methodology for Low Power/Shutdown Fire PRA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-22

... NUCLEAR REGULATORY COMMISSION [NRC-2011-0295] Methodology for Low Power/Shutdown Fire PRA AGENCY.../Shutdown Fire PRA.'' In response to request from members of the public, the NRC is extending the public... risk assessment (PRA) method for quantitatively analyzing fire risk in commercial nuclear power plants...

40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

40 CFR Table 15 to Subpart Xxxx of... - Requirements for Reports

Code of Federal Regulations, 2011 CFR

2011-07-01

... had a startup, shutdown or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance report must include the information... requirements for annual reporting in § 63.6010(f). 2. Immediate startup, shutdown, and malfunction report if...

78 FR 20855 - State Implementation Plans: Response to Petition for Rulemaking; Findings of Substantial...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-08

... SIP Calls To Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and... SIP Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and... Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and Malfunction...

40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What happens during periods of startup... of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Performance Testing ...

40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Performance Testing ...

40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What happens during periods of startup... of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Performance Testing ...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

40 CFR 63.8635 - What reports must I submit and when?

Code of Federal Regulations, 2012 CFR

2012-07-01

... of report and beginning and ending dates of the reporting period. (4) If you had a startup, shutdown... section. This includes periods of startup, shutdown, malfunction, and routine control device maintenance... (e)(1) through (13) of this section. This includes periods of startup, shutdown, malfunction, and...

40 CFR 63.10 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... relevant records for such source of— (i) The occurrence and duration of each startup or shutdown when the startup or shutdown causes the source to exceed any applicable emission limitation in the relevant... startup or shutdown when the source exceeded applicable emission limitations in a relevant standard and...

40 CFR 63.1367 - Recordkeeping requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) of subpart A of this part. (3) Startup, shutdown, and malfunction plan. The owner or operator of an affected source shall develop a written startup, shutdown, and malfunction plan as specified in § 63.6(e)(3... during periods of startup, shutdown, and malfunction and a program for corrective action for a...

40 CFR 63.10 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... relevant records for such source of— (i) The occurrence and duration of each startup or shutdown when the startup or shutdown causes the source to exceed any applicable emission limitation in the relevant... startup or shutdown when the source exceeded applicable emission limitations in a relevant standard and...

40 CFR 63.8635 - What reports must I submit and when?

Code of Federal Regulations, 2013 CFR

2013-07-01

... of report and beginning and ending dates of the reporting period. (4) If you had a startup, shutdown... section. This includes periods of startup, shutdown, malfunction, and routine control device maintenance... (e)(1) through (13) of this section. This includes periods of startup, shutdown, malfunction, and...

40 CFR 63.1346 - Operating limits for kilns.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., is not exceeded, except during periods of startup and shutdown when the temperature limit may be... not exceeded, except during periods of startup/shutdown when the temperature limit may be exceeded by... periods of startup/shutdown when the temperature limit may be exceeded by no more than 10 percent. (b) The...

40 CFR 63.10 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... relevant records for such source of— (i) The occurrence and duration of each startup or shutdown when the startup or shutdown causes the source to exceed any applicable emission limitation in the relevant... startup or shutdown when the source exceeded applicable emission limitations in a relevant standard and...

40 CFR 63.10 - Recordkeeping and reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... relevant records for such source of— (i) The occurrence and duration of each startup or shutdown when the startup or shutdown causes the source to exceed any applicable emission limitation in the relevant... startup or shutdown when the source exceeded applicable emission limitations in a relevant standard and...

40 CFR 63.8635 - What reports must I submit and when?

Code of Federal Regulations, 2014 CFR

2014-07-01

... of report and beginning and ending dates of the reporting period. (4) If you had a startup, shutdown... section. This includes periods of startup, shutdown, malfunction, and routine control device maintenance... (e)(1) through (13) of this section. This includes periods of startup, shutdown, malfunction, and...

40 CFR 63.1346 - Operating limits for kilns.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., is not exceeded, except during periods of startup and shutdown when the temperature limit may be... not exceeded, except during periods of startup/shutdown when the temperature limit may be exceeded by... periods of startup/shutdown when the temperature limit may be exceeded by no more than 10 percent. (b) The...

40 CFR 63.8635 - What reports must I submit and when?

Code of Federal Regulations, 2011 CFR

2011-07-01

... of report and beginning and ending dates of the reporting period. (4) If you had a startup, shutdown... section. This includes periods of startup, shutdown, malfunction, and routine control device maintenance... (e)(1) through (13) of this section. This includes periods of startup, shutdown, malfunction, and...

ICESat-2 laser technology development

NASA Astrophysics Data System (ADS)

Edwards, Ryan; Sawruk, Nick W.; Hovis, Floyd E.; Burns, Patrick; Wysocki, Theodore; Rudd, Joe; Walters, Brooke; Fakhoury, Elias; Prisciandaro, Vincent

2013-09-01

A number of ICESat-2 system requirements drove the technology evolution and the system architecture for the laser transmitter Fibertek has developed for the mission.. These requirements include the laser wall plug efficiency, laser reliability, high PRF (10kHz), short-pulse (<1.5ns), relatively narrow spectral line-width, and wave length tunability. In response to these requirements Fibertek developed a frequency-doubled, master oscillator/power amplifier (MOPA) laser that incorporates direct pumped diode pumped Nd:YVO4 as the gain media, Another guiding force in the system design has been extensive hardware life testing that Fibertek has completed. This ongoing hardware testing and development evolved the system from the original baseline brass board design to the more robust flight laser system. The final design meets or exceeds all NASA requirements and is scalable to support future mission requirements.

Directly solar-pumped iodine laser for beamed power transmission in space

NASA Technical Reports Server (NTRS)

Choi, S. H.; Meador, W. E.; Lee, J. H.

1992-01-01

A new approach for development of a 50-kW directly solar-pumped iodine laser (DSPIL) system as a space-based power station was made using a confocal unstable resonator (CUR). The CUR-based DSPIL has advantages, such as performance enhancement, reduction of total mass, and simplicity which alleviates the complexities inherent in the previous system, master oscillator/power amplifier (MOPA) configurations. In this design, a single CUR-based DSPIL with 50-kW output power was defined and compared to the MOPA-based DSPIL. Integration of multiple modules for power requirements more than 50-kW is physically and structurally a sound approach as compared to building a single large system. An integrated system of multiple modules can respond to various mission power requirements by combining and aiming the coherent beams at the user's receiver.

A novel laser-induced fluorescence scheme for Ar-I in a plasma.

PubMed

Short, Zachary D; Siddiqui, M Umair; Henriquez, Miguel F; McKee, John S; Scime, Earl E

2016-01-01

Here we describe a novel infrared laser-induced fluorescence scheme for the 1s2 state of Ar-I using an 841.052 nm (vacuum) Sacher tunable diode laser oscillator and compare it to an established 667.913 nm (vacuum) 1s4-pumping Ar-I LIF scheme using a master oscillator power amplifier laser [A. M. Keesee et al. Rev. Sci. Instrum. 75, 4091 (2004)]. The novel scheme exhibits a significantly greater signal-to-noise ratio for a given injected laser power than the established scheme. We argue that this is caused by less intense spontaneous Ar-I radiation near the LIF emission wavelength for the 1s2 scheme as compared to the 1s4 scheme. In addition we present an updated iodine cell spectrum around the 1s4 LIF scheme pump wavelength.

The application of artificial intelligent techniques to accelerator operations at McMaster University

NASA Astrophysics Data System (ADS)

Poehlman, W. F. S.; Garland, Wm. J.; Stark, J. W.

1993-06-01

In an era of downsizing and a limited pool of skilled accelerator personnel from which to draw replacements for an aging workforce, the impetus to integrate intelligent computer automation into the accelerator operator's repertoire is strong. However, successful deployment of an "Operator's Companion" is not trivial. Both graphical and human factors need to be recognized as critical areas that require extra care when formulating the Companion. They include interactive graphical user's interface that mimics, for the operator, familiar accelerator controls; knowledge of acquisition phases during development must acknowledge the expert's mental model of machine operation; and automated operations must be seen as improvements to the operator's environment rather than threats of ultimate replacement. Experiences with the PACES Accelerator Operator Companion developed at two sites over the past three years are related and graphical examples are given. The scale of the work involves multi-computer control of various start-up/shutdown and tuning procedures for Model FN and KN Van de Graaff accelerators. The response from licensing agencies has been encouraging.

Cardiogenic programming of human pluripotent stem cells by dose-controlled activation of EOMES.

PubMed

Pfeiffer, Martin J; Quaranta, Roberto; Piccini, Ilaria; Fell, Jakob; Rao, Jyoti; Röpke, Albrecht; Seebohm, Guiscard; Greber, Boris

2018-01-30

Master cell fate determinants are thought to induce specific cell lineages in gastrulation by orchestrating entire gene programs. The T-box transcription factor EOMES (eomesodermin) is crucially required for the development of the heart-yet it is equally important for endoderm specification suggesting that it may act in a context-dependent manner. Here, we define an unrecognized interplay between EOMES and the WNT signaling pathway in controlling cardiac induction by using loss and gain-of-function approaches in human embryonic stem cells. Dose-dependent EOMES induction alone can fully replace a cocktail of signaling molecules otherwise essential for the specification of cardiogenic mesoderm. Highly efficient cardiomyocyte programming by EOMES mechanistically involves autocrine activation of canonical WNT signaling via the WNT3 ligand, which necessitates a shutdown of this axis at a subsequent stage. Our findings provide insights into human germ layer induction and bear biotechnological potential for the robust production of cardiomyocytes from engineered stem cells.

SEMICONDUCTOR INTEGRATED CIRCUITS: An asymmetric MOSFET-C band-pass filter with on-chip charge pump auto-tuning

NASA Astrophysics Data System (ADS)

Fangxiong, Chen; Min, Lin; Heping, Ma; Hailong, Jia; Yin, Shi; Forster, Dai

2009-08-01

An asymmetric MOSFET-C band-pass filter (BPF) with on chip charge pump auto-tuning is presented. It is implemented in UMC (United Manufacturing Corporation) 0.18 μm CMOS process technology. The filter system with auto-tuning uses a master-slave technique for continuous tuning in which the charge pump outputs 2.663 V, much higher than the power supply voltage, to improve the linearity of the filter. The main filter with third order low-pass and second order high-pass properties is an asymmetric band-pass filter with bandwidth of 2.730-5.340 MHz. The in-band third order harmonic input intercept point (IIP3) is 16.621 dBm, with 50 Ω as the source impedance. The input referred noise is about 47.455 μVrms. The main filter dissipates 3.528 mW while the auto-tuning system dissipates 2.412 mW from a 1.8 V power supply. The filter with the auto-tuning system occupies 0.592 mm2 and it can be utilized in GPS (global positioning system) and Bluetooth systems.

Burnable absorber arrangement for fuel bundle

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

Crowther, R.L.; Townsend, D.B.

1986-12-16

This patent describes a boiling water reactor core whose operation is characterized by a substantial proportion of steam voids with concomitantly reduced moderation toward the top of the core when the reactor is in its hot operating condition. The reduced moderation leads to slower burnup and greater conversion ratio in an upper core region so that when the reactor is in its cold shut down condition the resulting relatively increased moderation in the upper core region is accompanied by a reactivity profile that peaks in the upper core region. A fuel assembly is described comprising; a component of fissile materialmore » distributed over a substantial axial extent of the fuel assembly; and a component of neutron absorbing material having an axial distribution characterized by an enhancement in an axial zone of the fuel assembly, designated the cold shutdown control zone, corresponding to at least a portion of the axial region of the core when the cold shutdown reactivity peaks. The aggregate amount of neutron absorbing material in the cold shutdown zone of the fuel assembly is greater than the aggregate amount of neutron absorbing material in the axial zones of the fuel assembly immediately above and immediately below the cold shutdown control zone whereby the cold shutdown reactivity peak is reduced relative to the cold shutdown reactivity in the zones immediately above and immediately below the cold shutdown control zone. The cold shutdown zone has an axial extent measured from the bottom of the fuel assembly in the range between 68-88 percent of the height of the fissile material in the fuel assembly.« less

30 CFR 57.8534 - Shutdown or failure of auxiliary fans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shutdown or failure of auxiliary fans. 57.8534... Ventilation Underground Only § 57.8534 Shutdown or failure of auxiliary fans. (a) Auxiliary fans installed and... fan maintenance or fan adjustments where air quality is maintained in compliance with the applicable...

76 FR 20707 - Notice of Possible Shutdown of Investigative Activities

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... receives funding and the period of the shutdown ends, all schedules will resume starting with the day on... if the Commission resumes operations by April 14, 2011. Should the shutdown not end before April 14.... The Commission's World Wide Web site, at http://www.usitc.gov , will be updated to the extent...

40 CFR Table 14 to Subpart Wwww of... - Requirements for Reports

Code of Federal Regulations, 2010 CFR

2010-07-01

....5910(b). c. The information in § 63.10(d)(5)(i) if you had a startup, shutdown or malfunction during the reporting period, and you took actions consistent with your startup, shutdown, and malfunction plan Semiannually according to the requirements in § 63.5910(b). 2. An immediate startup, shutdown, and...

40 CFR Table 7 to Subpart Aaaaa of... - Requirements for Reports

Code of Federal Regulations, 2011 CFR

2011-07-01

.... If you had a startup, shutdown or malfunction during the reporting period and you took actions...) Semiannually according to the requirements in § 63.7131(b). 2. An immediate startup, shutdown, and malfunction report if you had a startup, shutdown, or malfunction during the reporting period that is not consistent...

40 CFR Table 7 to Subpart Aaaaa of... - Requirements for Reports

Code of Federal Regulations, 2012 CFR

2012-07-01

.... If you had a startup, shutdown or malfunction during the reporting period and you took actions...) Semiannually according to the requirements in § 63.7131(b). 2. An immediate startup, shutdown, and malfunction report if you had a startup, shutdown, or malfunction during the reporting period that is not consistent...

40 CFR Table 7 to Subpart Aaaaa of... - Requirements for Reports

Code of Federal Regulations, 2010 CFR

2010-07-01

.... If you had a startup, shutdown or malfunction during the reporting period and you took actions...) Semiannually according to the requirements in § 63.7131(b). 2. An immediate startup, shutdown, and malfunction report if you had a startup, shutdown, or malfunction during the reporting period that is not consistent...

40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during CISWI unit startups, shutdowns, or malfunctions. (b) Each...

40 CFR 63.1570 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... control equipment. (d) You must develop a written startup, shutdown, and malfunction plan (SSMP) according... includes periods of startup, shutdown, and malfunction. You also must report each instance in which you did...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What happens during periods of startup... happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during CISWI unit startups, shutdowns, or malfunctions. (b) Each...

40 CFR 63.5555 - How do I demonstrate continuous compliance with the emission limits, operating limits, and work...

Code of Federal Regulations, 2011 CFR

2011-07-01

... startup, shutdown, and malfunction. These instances are deviations from the emission limits, operating... during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the... determine whether deviations that occur during a period you identify as a startup, shutdown, or malfunction...

40 CFR Table 14 to Subpart Wwww of... - Requirements for Reports

Code of Federal Regulations, 2011 CFR

2011-07-01

....5910(b). c. The information in § 63.10(d)(5)(i) if you had a startup, shutdown or malfunction during the reporting period, and you took actions consistent with your startup, shutdown, and malfunction plan Semiannually according to the requirements in § 63.5910(b). 2. An immediate startup, shutdown, and...

40 CFR 63.9040 - How do I demonstrate continuous compliance with the emission limitations and work practice...

Code of Federal Regulations, 2011 CFR

2011-07-01

... to you. This includes periods of startup, shutdown, and malfunction. These instances are deviations... during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the... determine whether deviations that occur during a period of startup, shutdown, or malfunction are violations...

40 CFR Table 7 to Subpart Aaaaa of... - Requirements for Reports

Code of Federal Regulations, 2013 CFR

2013-07-01

.... If you had a startup, shutdown or malfunction during the reporting period and you took actions...) Semiannually according to the requirements in § 63.7131(b). 2. An immediate startup, shutdown, and malfunction report if you had a startup, shutdown, or malfunction during the reporting period that is not consistent...

40 CFR 63.5555 - How do I demonstrate continuous compliance with the emission limits, operating limits, and work...

Code of Federal Regulations, 2010 CFR

2010-07-01

... startup, shutdown, and malfunction. These instances are deviations from the emission limits, operating... during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the... determine whether deviations that occur during a period you identify as a startup, shutdown, or malfunction...

40 CFR 63.1570 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... control equipment. (d) You must develop a written startup, shutdown, and malfunction plan (SSMP) according... includes periods of startup, shutdown, and malfunction. You also must report each instance in which you did...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.1570 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... control equipment. (d) You must develop a written startup, shutdown, and malfunction plan (SSMP) according... includes periods of startup, shutdown, and malfunction. You also must report each instance in which you did...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What happens during periods of startup...-Emission Limitations and Operating Limits § 60.2685 What happens during periods of startup, shutdown, and... startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3 hours. Effective Date...

40 CFR Table 7 to Subpart Aaaaa of... - Requirements for Reports

Code of Federal Regulations, 2014 CFR

2014-07-01

.... If you had a startup, shutdown or malfunction during the reporting period and you took actions...) Semiannually according to the requirements in § 63.7131(b). 2. An immediate startup, shutdown, and malfunction report if you had a startup, shutdown, or malfunction during the reporting period that is not consistent...

40 CFR 63.1570 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... control equipment. (d) You must develop a written startup, shutdown, and malfunction plan (SSMP) according... includes periods of startup, shutdown, and malfunction. You also must report each instance in which you did...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR Table 15 to Subpart Xxxx of... - Requirements for Reports

Code of Federal Regulations, 2013 CFR

2013-07-01

....6010(f). c. If you had a startup, shutdown or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance report must include... you meet the requirements for annual reporting in § 63.6010(f). 2. Immediate startup, shutdown, and...

40 CFR 63.1570 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... control equipment. (d) You must develop a written startup, shutdown, and malfunction plan (SSMP) according... includes periods of startup, shutdown, and malfunction. You also must report each instance in which you did...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.9641 - What reports must I submit and when?

Code of Federal Regulations, 2014 CFR

2014-07-01

... and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan... information in paragraphs (b)(7)(i) and (ii) of this section. This includes periods of startup, shutdown, and...

40 CFR 63.9814 - What reports must I submit and when?

Code of Federal Regulations, 2011 CFR

2011-07-01

... beginning and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction... (d)(1) and (2) of this section. This includes periods of startup, shutdown, and malfunction. (1) The... section. This includes periods of startup, shutdown, and malfunction. (1) The total operating time of each...

40 CFR 63.9814 - What reports must I submit and when?

Code of Federal Regulations, 2012 CFR

2012-07-01

... beginning and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction... (d)(1) and (2) of this section. This includes periods of startup, shutdown, and malfunction. (1) The... section. This includes periods of startup, shutdown, and malfunction. (1) The total operating time of each...

40 CFR 63.9641 - What reports must I submit and when?

Code of Federal Regulations, 2012 CFR

2012-07-01

... and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan... information in paragraphs (b)(7)(i) and (ii) of this section. This includes periods of startup, shutdown, and...

40 CFR 63.9814 - What reports must I submit and when?

Code of Federal Regulations, 2014 CFR

2014-07-01

... beginning and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction... (d)(1) and (2) of this section. This includes periods of startup, shutdown, and malfunction. (1) The... section. This includes periods of startup, shutdown, and malfunction. (1) The total operating time of each...

40 CFR 63.9641 - What reports must I submit and when?

Code of Federal Regulations, 2013 CFR

2013-07-01

... and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan... information in paragraphs (b)(7)(i) and (ii) of this section. This includes periods of startup, shutdown, and...

40 CFR 63.9641 - What reports must I submit and when?

Code of Federal Regulations, 2011 CFR

2011-07-01

... and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan... information in paragraphs (b)(7)(i) and (ii) of this section. This includes periods of startup, shutdown, and...

40 CFR 63.9814 - What reports must I submit and when?

Code of Federal Regulations, 2013 CFR

2013-07-01

... beginning and ending dates of the reporting period. (4) If you had a startup, shutdown, or malfunction... (d)(1) and (2) of this section. This includes periods of startup, shutdown, and malfunction. (1) The... section. This includes periods of startup, shutdown, and malfunction. (1) The total operating time of each...

77 FR 69507 - Proposed Model Safety Evaluation for Plant-Specific Adoption of Technical Specifications Task...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-19

..., ``Revise Shutdown Margin Definition To Address Advanced Fuel Designs'' AGENCY: Nuclear Regulatory... Shutdown Margin Definition to Address Advanced Fuel Designs.'' DATES: Comment period expires on December 19... address newer BWR fuel designs, which may be more reactive at shutdown temperatures above 68[emsp14][deg]F...

Test Results of the RS-44 Integrated Component Evaluator Liquid Oxygen/Hydrogen Rocket Engine

NASA Technical Reports Server (NTRS)

Sutton, R. F.; Lariviere, B. W.

1993-01-01

An advanced LOX/LH2 expander cycle rocket engine, producing 15,000 lbf thrust for Orbital Transfer Vehicle missions, was tested to determine ignition, transition, and main stage characteristics. Detail design and fabrication of the pump fed RS44 integrated component evaluator (ICE) was accomplished using company discretionary resources and was tested under this contracted effort. Successful demonstrations were completed to about the 50 percent fuel turbopump power level (87,000 RPM), but during this last test, a high pressure fuel turbopump (HPFTP) bearing failed curtailing the test program. No other hardware were affected by the HPFTP premature shutdown. The ICE operations matched well with the predicted start transient simulations. The tests demonstrated the feasibility of a high performance advanced expander cycle engine. All engine components operated nominally, except for the HPFTP, during the engine hot-fire tests. A failure investigation was completed using company discretionary resources.

Recent Operational Experience with the Internal Thermal Control System Dual-Membrane Gas Trap

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Lukens, Clark; Reeves, Daniel R.; Holt, James M.

2004-01-01

A dual-membrane gas trap is currently used to remove gas bubbles from the Internal Thermal Control System (ITCS) coolant on board the International Space Station. The gas trap consists of concentric tube membrane pairs, comprised of outer hydrophilic tubes and inner hydrophobic fibers. Liquid coolant passes through the outer hydrophilic membrane, which traps the gas bubbles. The inner hydrophobic fiber allows the trapped gas bubbles to pass through and vent to the ambient atmosphere in the cabin. The gas removal performance and operational lifetime of the gas trap have been affected by contamination in the ITCS coolant. However, the gas trap has performed flawlessly with regard to its purpose of preventing gas bubbles from causing depriming, overspeed, and shutdown of the ITCS pump. This paper discusses on-orbit events over the course of the last year related to the performance and functioning of the gas trap.

Effects of Surfactant Contamination on the Next Generation Gas Trap for the ISS Internal Thermal Control System

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Lukens, Clark; Reeves, Daniel R.; Holt, James M.

2004-01-01

The current dual-membrane gas trap is designed to remove non-condensed gas bubbles from the Internal Thermal Control System (ITCS) coolant on board the International Space Station (ISS). To date it has successfully served its purpose of preventing gas bubbles from causing depriming, overspeed, and shutdown of the ITCS pump. However, contamination in the ITCS coolant has adversely affected the gas venting rate and lifetime of the gas trap, warranting a development effort for a next-generation gas trap. Previous testing has shown that a hydrophobic-only design is capable of performing even better than the current dual-membrane design for both steady-state gas removal and gas slug removal in clean deionized water. This paper presents results of testing to evaluate the effects of surfactant contamination on the steady-state performance of the hydrophobic-only design.

40 CFR 63.8248 - What other requirements must I meet?

Code of Federal Regulations, 2011 CFR

2011-07-01

... startup, shutdown, and malfunction. (2) You must report each instance in which you did not meet each work practice standard in § 63.8192 that applies to you. This includes periods of startup, shutdown, and... value was out of range. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63...

40 CFR 63.5555 - How do I demonstrate continuous compliance with the emission limits, operating limits, and work...

Code of Federal Regulations, 2014 CFR

2014-07-01

... periods of startup, shutdown, and malfunction. These instances are deviations from the emission limits...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...

40 CFR 63.8248 - What other requirements must I meet?

Code of Federal Regulations, 2013 CFR

2013-07-01

... startup, shutdown, and malfunction. (2) You must report each instance in which you did not meet each work practice standard in § 63.8192 that applies to you. This includes periods of startup, shutdown, and... value was out of range. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63...

40 CFR 63.5555 - How do I demonstrate continuous compliance with the emission limits, operating limits, and work...

Code of Federal Regulations, 2013 CFR

2013-07-01

... periods of startup, shutdown, and malfunction. These instances are deviations from the emission limits...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...

40 CFR Table 1 to Subpart Aaaa of... - Applicability of NESHAP General Provisions to Subpart AAAA

Code of Federal Regulations, 2010 CFR

2010-07-01

... reconstructed sources 63.6(e) Operation and maintenance requirements, startup, shutdown and malfunction plan...(b)(2)(i)-(b)(2)(v) General recordkeeping requirements 63.10(d)(5) If actions taken during a startup, shutdown and malfunction plan are consistent with the procedures in the startup, shutdown and malfunction...

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 9 2013-07-01 2013-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

40 CFR 63.7835 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... that applies to you. This includes periods of startup, shutdown, and malfunction. You also must report...) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the...

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

40 CFR 63.7835 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... that applies to you. This includes periods of startup, shutdown, and malfunction. You also must report...) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the...

40 CFR 63.8248 - What other requirements must I meet?

Code of Federal Regulations, 2014 CFR

2014-07-01

... startup, shutdown, and malfunction. (2) You must report each instance in which you did not meet each work practice standard in § 63.8192 that applies to you. This includes periods of startup, shutdown, and... value was out of range. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63...

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 9 2012-07-01 2012-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 9 2014-07-01 2014-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

40 CFR Table 14 to Subpart Wwww of... - Requirements for Reports

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements in § 63.5910(b). c. The information in § 63.10(d)(5)(i) if you had a startup, shutdown or malfunction during the reporting period, and you took actions consistent with your startup, shutdown, and malfunction plan Semiannually according to the requirements in § 63.5910(b). 2. An immediate startup, shutdown...

40 CFR Table 14 to Subpart Wwww of... - Requirements for Reports

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements in § 63.5910(b). c. The information in § 63.10(d)(5)(i) if you had a startup, shutdown or malfunction during the reporting period, and you took actions consistent with your startup, shutdown, and malfunction plan Semiannually according to the requirements in § 63.5910(b). 2. An immediate startup, shutdown...

40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 8 2011-07-01 2011-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

40 CFR 63.7835 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... that applies to you. This includes periods of startup, shutdown, and malfunction. You also must report...) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the...

40 CFR Table 14 to Subpart Wwww of... - Requirements for Reports

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements in § 63.5910(b). c. The information in § 63.10(d)(5)(i) if you had a startup, shutdown or malfunction during the reporting period, and you took actions consistent with your startup, shutdown, and malfunction plan Semiannually according to the requirements in § 63.5910(b). 2. An immediate startup, shutdown...

40 CFR Table 1 to Subpart Aaaa of... - Applicability of NESHAP General Provisions to Subpart AAAA

Code of Federal Regulations, 2011 CFR

2011-07-01

... reconstructed sources 63.6(e) Operation and maintenance requirements, startup, shutdown and malfunction plan...(b)(2)(i)-(b)(2)(v) General recordkeeping requirements 63.10(d)(5) If actions taken during a startup, shutdown and malfunction plan are consistent with the procedures in the startup, shutdown and malfunction...

40 CFR 63.5555 - How do I demonstrate continuous compliance with the emission limits, operating limits, and work...

Code of Federal Regulations, 2012 CFR

2012-07-01

... periods of startup, shutdown, and malfunction. These instances are deviations from the emission limits...), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you... Administrator will determine whether deviations that occur during a period you identify as a startup, shutdown...

40 CFR 63.7835 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... that applies to you. This includes periods of startup, shutdown, and malfunction. You also must report...) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the...

40 CFR 63.7835 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2011 CFR

2011-07-01

... that applies to you. This includes periods of startup, shutdown, and malfunction. You also must report...) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you demonstrate to the...

Defense.gov Special Report: Government Shutdown - What You Need to Know

Science.gov Websites

Department is taking to plan for a possible government shutdown. Document Plan for Agency Operations During agencies should plan for a potential shutdown. Document Guidance for Continuation of Operations in The Contingency Plan Guidance for Continuation of Essential Operations in the Absence of Available Appropriations

75 FR 48283 - Liability for Termination of Single-Employer Plans; Treatment of Substantial Cessation of Operations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-10

... self- reporting of events that PBGC now learns of only through its own investigations and may enable... to retire sooner upon learning of a shutdown that would eliminate her job, the separation would be the result of the shutdown; whereas if (before learning of the shutdown) she had been planning to...

885-nm Pumped Ceramic Nd:YAG Master Oscillator Power Amplifier Laser System

NASA Technical Reports Server (NTRS)

Yu, Anthony

2012-01-01

The performance of a traditional diode pumped solid-state laser that is typically pumped with 808-nm laser diode array (LDA) and crystalline Nd:YAG was improved by using 885-nm LDAs and ceramic Nd:YAG. The advantage is lower quantum defect, which will improve the thermal loading on laser gain medium, resulting in a higher-performance laser. The use of ceramic Nd:YAG allows a higher Nd dopant level that will make up the lower absorption at the 885-nm wavelength on Nd:YAG. When compared to traditional 808-nm pump, 885-nm diodes will have 30% less thermal load (or wasted heat) and will thus see a similar percentage improvement in the overall laser efficiency. In order to provide a more efficient laser system for future flight missions that require the use of low-repetition- rate (1% Nd. To make certain that the absorption at 885 nm is on the same par as the 808-nm diode, the Nd:YAG material needs to be doped with higher concentration of Nd. Ceramic Nd:YAG is the only material that can be tailored to specific needs.

Fuel cell system shutdown with anode pressure control

DOEpatents

Clingerman, Bruce J.; Doan, Tien M.; Keskula, Donald H.

2002-01-01

A venting methodology and pressure sensing and vent valving arrangement for monitoring anode bypass valve operating during the normal shutdown of a fuel cell apparatus of the type used in vehicle propulsion systems. During a normal shutdown routine, the pressure differential between the anode inlet and anode outlet is monitored in real time in a period corresponding to the normal closing speed of the anode bypass valve and the pressure differential at the end of the closing cycle of the anode bypass valve is compared to the pressure differential at the beginning of the closing cycle. If the difference in pressure differential at the beginning and end of the anode bypass closing cycle indicates that the anode bypass valve has not properly closed, a system controller switches from a normal shutdown mode to a rapid shutdown mode in which the anode inlet is instantaneously vented by rapid vents.

Picosecond laser with 11 W output power at 1342 nm based on composite multiple doping level Nd:YVO4 crystal

NASA Astrophysics Data System (ADS)

Rodin, Aleksej M.; Grishin, Mikhail; Michailovas, Andrejus

2016-01-01

We report results of design and optimization of high average output power picosecond and nanosecond laser operating at 1342 nm wavelength. Developed for selective micromachining, this DPSS laser is comprised of master oscillator, regenerative amplifier and output pulse control module. Passively mode-locked by means of semiconductor saturable absorber mirror and pumped with 808 nm wavelength Nd:YVO4 master oscillator emits 12.5 ps pulses at repetition rate of 55 MHz with average output power of ∼100 mW. The four-pass confocal delay line forms a longest part of the oscillator cavity in order to suppress thermo-mechanical misalignment. Picked from the train seed pulses were injected to the cavity of regenerative amplifier based on composite Nd:YVO4 crystal with diffusion-bonded segments of multiple Nd doping concentration end-pumped at 880 nm wavelength. Laser produces pulses of ∼13 ps duration at 300 kHz repetition rate with average output power of 11 W and nearly diffraction limited beam quality of M2∼1.03. Attained high peak power ∼2.8 MW facilitates conversion to the 2nd, 3rd and 6th harmonics at 671 nm, 447 nm and 224 nm wavelengths with 80%, 50% and 15% efficiency respectively. Without seeding the regenerative amplifier transforms to electro-optically cavity-dumped Q-switched laser providing 10 ns output pulses at high repetition rates with beam propagation factor of M2∼1.06.

78 FR 38739 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-27

...The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 1 of Regulatory Guide (RG) 1.185, ``Standard Format and Content for Post-shutdown Decommissioning Activities Report.'' This guide describes a method that the NRC staff considers acceptable for use in complying with the Commission's requirements regarding the submission of a post-shutdown decommissioning activities report (PSDAR).

77 FR 75198 - Standard Format and Content for Post-Shutdown Decommissioning Activities Report

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-19

...The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment draft regulatory guide (DG), DG-1272, ``Standard Format and Content for Post-shutdown Decommissioning Activities Report.'' This guide describes a method that the NRC staff considers acceptable for use in complying with the Commission's requirements regarding the submission of a post-shutdown decommissioning activities report (PSDAR).

40 CFR 63.8691 - How do I demonstrate continuous compliance with the operating limits?

Code of Federal Regulations, 2014 CFR

2014-07-01

... operating limit in Table 5 to this subpart that applies to you. This includes periods of startup, shutdown... §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction... of startup, shutdown, or malfunction are violations, according to the provisions in § 63.6(e). [68 FR...

40 CFR 63.9925 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... includes periods of startup, shutdown, and malfunction. You must also report each instance in which you did... § 63.9931. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.8691 - How do I demonstrate continuous compliance with the operating limits?

Code of Federal Regulations, 2010 CFR

2010-07-01

... operating limit in Table 5 to this subpart that applies to you. This includes periods of startup, shutdown... §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction... of startup, shutdown, or malfunction are violations, according to the provisions in § 63.6(e). [68 FR...

40 CFR 63.8691 - How do I demonstrate continuous compliance with the operating limits?

Code of Federal Regulations, 2011 CFR

2011-07-01

... operating limit in Table 5 to this subpart that applies to you. This includes periods of startup, shutdown... §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction... of startup, shutdown, or malfunction are violations, according to the provisions in § 63.6(e). [68 FR...

40 CFR 63.9925 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... includes periods of startup, shutdown, and malfunction. You must also report each instance in which you did... § 63.9931. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.9925 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... includes periods of startup, shutdown, and malfunction. You must also report each instance in which you did... § 63.9931. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.9925 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2011 CFR

2011-07-01

... includes periods of startup, shutdown, and malfunction. You must also report each instance in which you did... § 63.9931. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.8691 - How do I demonstrate continuous compliance with the operating limits?

Code of Federal Regulations, 2012 CFR

2012-07-01

... operating limit in Table 5 to this subpart that applies to you. This includes periods of startup, shutdown... §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction... of startup, shutdown, or malfunction are violations, according to the provisions in § 63.6(e). [68 FR...

40 CFR 63.9925 - What other requirements must I meet to demonstrate continuous compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... includes periods of startup, shutdown, and malfunction. You must also report each instance in which you did... § 63.9931. (b) Startups, shutdowns, and malfunctions. (1) Consistent with §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction are not violations if you...

40 CFR 63.8691 - How do I demonstrate continuous compliance with the operating limits?

Code of Federal Regulations, 2013 CFR

2013-07-01

... operating limit in Table 5 to this subpart that applies to you. This includes periods of startup, shutdown... §§ 63.6(e) and 63.7(e)(1), deviations that occur during a period of startup, shutdown, or malfunction... of startup, shutdown, or malfunction are violations, according to the provisions in § 63.6(e). [68 FR...

Rigorous-two-Steps scheme of TRIPOLI-4® Monte Carlo code validation for shutdown dose rate calculation

NASA Astrophysics Data System (ADS)

Jaboulay, Jean-Charles; Brun, Emeric; Hugot, François-Xavier; Huynh, Tan-Dat; Malouch, Fadhel; Mancusi, Davide; Tsilanizara, Aime

2017-09-01

After fission or fusion reactor shutdown the activated structure emits decay photons. For maintenance operations the radiation dose map must be established in the reactor building. Several calculation schemes have been developed to calculate the shutdown dose rate. These schemes are widely developed in fusion application and more precisely for the ITER tokamak. This paper presents the rigorous-two-steps scheme implemented at CEA. It is based on the TRIPOLI-4® Monte Carlo code and the inventory code MENDEL. The ITER shutdown dose rate benchmark has been carried out, results are in a good agreement with the other participant.

Impacts of flare emissions from an ethylene plant shutdown to regional air quality

NASA Astrophysics Data System (ADS)

Wang, Ziyuan; Wang, Sujing; Xu, Qiang; Ho, Thomas

2016-08-01

Critical operations of chemical process industry (CPI) plants such as ethylene plant shutdowns could emit a huge amount of VOCs and NOx, which may result in localized and transient ozone pollution events. In this paper, a general methodology for studying dynamic ozone impacts associated with flare emissions from ethylene plant shutdowns has been developed. This multi-scale simulation study integrates process knowledge of plant shutdown emissions in terms of flow rate and speciation together with regional air-quality modeling to quantitatively investigate the sensitivity of ground-level ozone change due to an ethylene plant shutdown. The study shows the maximum hourly ozone increments can vary significantly by different plant locations and temporal factors including background ozone data and solar radiation intensity. It helps provide a cost-effective air-quality control strategy for industries by choosing the optimal starting time of plant shutdown operations in terms of minimizing the induced ozone impact (reduced from 34.1 ppb to 1.2 ppb in the performed case studies). This study provides valuable technical supports for both CPI and environmental policy makers on cost-effective air-quality controls in the future.

Complex of technologies and prototype systems for eco-friendly shutdown of the power-generating, process, capacitive, and transport equipment

NASA Astrophysics Data System (ADS)

Smorodin, A. I.; Red'kin, V. V.; Frolov, Y. D.; Korobkov, A. A.; Kemaev, O. V.; Kulik, M. V.; Shabalin, O. V.

2015-07-01

A set of technologies and prototype systems for eco-friendly shutdown of the power-generating, process, capacitive, and transport equipment is offered. The following technologies are regarded as core technologies for the complex: cryogenic technology nitrogen for displacement of hydrogen from the cooling circuit of turbine generators, cryo blasting of the power units by dioxide granules, preservation of the shutdown power units by dehydrated air, and dismantling and severing of equipment and structural materials of power units. Four prototype systems for eco-friendly shutdown of the power units may be built on the basis of selected technologies: Multimode nitrogen cryogenic system with four subsystems, cryo blasting system with CO2 granules for thermal-mechanical and electrical equipment of power units, and compressionless air-drainage systems for drying and storage of the shutdown power units and cryo-gas system for general severing of the steam-turbine power units. Results of the research and pilot and demonstration tests of the operational units of the considered technological systems allow applying the proposed technologies and systems in the prototype systems for shutdown of the power-generating, process, capacitive, and transport equipment.

Site 300 City Water Master Plan

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

Shaw, Jeff

Lawrence Livermore National Laboratory (LLNL), a scientific research facility, operates an experimental test site known as Site 300. The site is located in a remote area of southeastern Alameda County, California, and consists of about 100 facilities spread across 7,000-acres. The Site 300 water system includes groundwater wells and a system of storage tanks, booster pumps, and underground piping to distribute water to buildings and significant areas throughout the site. Site 300, which is classified as a non-transient non-community (NTNC) water system, serves approximately 110 employees through 109 service connections. The distribution system includes approximately 76,500-feet of water mains varyingmore » from 4- to 10-inches in diameter, mostly asbestos cement (AC) pipe, and eleven water storage tanks. The water system is divided into four pressure zones fed by three booster pump stations to tanks in each zone.« less

All-solid-state single longitudinal mode MOPA laser system

NASA Astrophysics Data System (ADS)

Zhang, Xiang; Gu, Haidong; Hu, Wenhua; Ren, Shilong

2018-03-01

Side diode pumped electro-optical Q Switching Nd: YAG is demonstrated as master oscillator. F-P etalon and twisted-mode cavity combined configuration is introduced to select longitudinal modes. The seed light experiences a round trip through the two flash pump amplifiers, in this device, the 4f image transmission system and SBS phase conjugate mirror is adopted in order to improved beam quality, by compensating the heat depolarization effect and eliminate wave-front distortion. In the condition of 1 or 5 repetitions of the wavelength at 1064nm, it produces the pulse energy of 300mJ, pulse width of 12ns, and energy instability (RMS) below 3% in single longitudinal mode operation. With a type two-phase matched KTP crystal, 532nm green light is yielded, at 1 Hz repetition rate, the pulse energy of green light is more than 150mJ.

TOR complex 1 regulates the yeast plasma membrane proton pump and pH and potassium homeostasis.

PubMed

Mahmoud, Shima; Planes, María Dolores; Cabedo, Marc; Trujillo, Cristina; Rienzo, Alessandro; Caballero-Molada, Marcos; Sharma, Sukesh C; Montesinos, Consuelo; Mulet, José Miguel; Serrano, Ramón

2017-07-01

We have identified in yeast a connection between two master regulators of cell growth: a biochemical connection involving the TORC1 protein kinase (which activates protein synthesis, nutrient uptake, and anabolism) and a biophysical connection involving the plasma membrane proton-pumping H + -ATPase Pma1 (which drives nutrient and K + uptake and regulates pH homeostasis). Raising the temperature to nonpermissive values in a TOR thermosensitive mutant decreases Pma1 activity. Rapamycin, a TORC1 inhibitor, inhibits Pma1 dependent on its receptor Fpr1 and on the protein phosphatase Sit4, a TORC1 effector. Mutation of either Sit4 or Tco89, a nonessential subunit of TORC1, decreases proton efflux, K + uptake, intracellular pH, cell growth, and tolerance to weak organic acids. Tco89 does not affect Pma1 activity but activates K + transport. © 2017 Federation of European Biochemical Societies.

A novel laser-induced fluorescence scheme for Ar-I in a plasma

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

Short, Zachary D., E-mail: zdshort@mix.wvu.edu; Siddiqui, M. Umair; Henriquez, Miguel F.

Here we describe a novel infrared laser-induced fluorescence scheme for the 1s{sub 2} state of Ar-I using an 841.052 nm (vacuum) Sacher tunable diode laser oscillator and compare it to an established 667.913 nm (vacuum) 1s{sub 4}-pumping Ar-I LIF scheme using a master oscillator power amplifier laser [A. M. Keesee et al. Rev. Sci. Instrum. 75, 4091 (2004)]. The novel scheme exhibits a significantly greater signal-to-noise ratio for a given injected laser power than the established scheme. We argue that this is caused by less intense spontaneous Ar-I radiation near the LIF emission wavelength for the 1s{sub 2} scheme asmore » compared to the 1s{sub 4} scheme. In addition we present an updated iodine cell spectrum around the 1s{sub 4} LIF scheme pump wavelength.« less

Characteristics of dioxin emissions at startup and shutdown of MSW incinerators.

PubMed

Tejima, Hajime; Nishigaki, Masahide; Fujita, Yasuyuki; Matsumoto, Akihiro; Takeda, Nobuo; Takaoka, Masaki

2007-01-01

Dioxin concentrations from municipal waste incinerators in Japan and elsewhere often show low concentrations that comply with legal limits (in this paper, the term "dioxin" designates WHO-TEQ: PCDD/Fs+dioxin-like PCB). However, such data is usually generated under normal steady state operational conditions, and there has been little investigation of releases occurring during startup and shutdown. It is important, therefore, to ascertain quantitatively emissions in an unsteady state (startup and shutdown) in order to correctly evaluate the relationship between emissions from a facility and the surrounding environment. The present study aimed to examine dioxin emissions of a continuously operated incinerator at startup and shutdown, and estimating the time period of greatest emission, and the processes causing dioxin generation. The startup process was divided into five stages and the shutdown into two; at each stage, dioxins in the flue gas were measured at the boiler outlet and the stack. From the concentration of dioxins and the flue gas volume at each stage, the amount of dioxins at startup and shutdown were calculated, and these were compared with that under steady state conditions. Dioxin concentration at the stack under steady state conditions was a very low level, while those at startup and shutdown were higher. In the case where dioxin concentration under a steady state is a low level like in this study, it is indicated that the total annual dioxin emission from a facility could be attributed to the startup periods.

Development of a decision support tool for seasonal water supply management incorporating system uncertainties and operational constraints

NASA Astrophysics Data System (ADS)

Wang, H.; Asefa, T.

2017-12-01

A real-time decision support tool (DST) for water supply system would consider system uncertainties, e.g., uncertain streamflow and demand, as well as operational constraints and infrastructure outage (e.g., pump station shutdown, an offline reservoir due to maintenance). Such DST is often used by water managers for resource allocation and delivery for customers. Although most seasonal DST used by water managers recognize those system uncertainties and operational constraints, most use only historical information or assume deterministic outlook of water supply systems. This study presents a seasonal DST that incorporates rainfall/streamflow uncertainties, seasonal demand outlook and system operational constraints. Large scale climate-information is captured through a rainfall simulator driven by a Bayesian non-homogeneous Markov Chain Monte Carlo model that allows non-stationary transition probabilities contingent on Nino 3.4 index. An ad-hoc seasonal demand forecasting model considers weather conditions explicitly and socio-economic factors implicitly. Latin Hypercube sampling is employed to effectively sample probability density functions of flow and demand. Seasonal system operation is modelled as a mixed-integer optimization problem that aims at minimizing operational costs. It embeds the flexibility of modifying operational rules at different components, e.g., surface water treatment plants, desalination facilities, and groundwater pumping stations. The proposed framework is illustrated at a wholesale water supplier in Southeastern United States, Tampa Bay Water. The use of the tool is demonstrated in proving operational guidance in a typical drawdown and refill cycle of a regional reservoir. The DST provided: 1) probabilistic outlook of reservoir storage and chance of a successful refill by the end of rainy season; 2) operational expectations for large infrastructures (e.g., high service pumps and booster stations) throughout the season. Other potential use of such DST is also discussed.

CONTROL RODS FOR NUCLEAR REACTORS

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

Bell, F.R.

1963-01-16

A means for controlling the control rod in emergency, when it is desired to shutdown the reactor with the shortest possible delay, is described. When the emergency occurs the control rod is allowed to drop freely under gravity from the control rod support tube into the bore in the reactor core. A normal shutdown is reached almost at the lowest rod position. In the shut-down position and also below it, the control rod had its full effect of reducing the level of activity in the core. When the shut-down position was reached, a brake came into action to decelerate themore » rod and reduce shock and the likelihood of damage. (C.E.S.)« less

Fallback level concepts for conventional and by-wire automotive brake systems

NASA Astrophysics Data System (ADS)

Retzer, H.; Mishra, R.; Ball, A.; Schmidt, K.

2012-05-01

Brake-by-wire represents the replacement of traditional brake components such as pumps, hoses, fluids, brake boosters, and master cylinders by electronic sensors and actuators. The different design of these brake concepts poses new challenges for the automotive industry with regard to availability and fallback levels in comparison to standard conventional brake systems. This contribution focuses on the development of appropriate fallback level concepts. Hardware-in-the-loop (HIL) techniques and field trials will be used to investigate the performance and the usability of such systems.

Forklift Truck, 4000-Pound-Capacity, Gasoline-Engine-Driven, Solid-Rubber-Tired, Allis-Chalmers Model ACC 45 NSN 3930-01-075-4937 -- Army User Survey,

DTIC Science & Technology

1982-03-01

to establish more realistic RAM data. 6. Action Taken. a. The undersigned contacted manufacturers regarding problems with the master link on the lift...Carburetor is updraft type and engine is equipped with a mechanical governor LP gas engine also avail able with same specifcations as above TRANSMISSIONS...torque by the converter Two oil-bathed, double-faced direction selec. tor clutches fully-enclosed gear-type pump. heat exchanger in bottom of radiator. 15

Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Attachment 5, Dewatering report. Revised final report

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

Not Available

1991-12-01

This report provides an update on dewatering activities at the Durango disposal embankment and presents recommendations for the work required to complete the closure of the cell in 1990 (Section 2). In October 1989, test pit investigations were performed and a toe trench was excavated at the eastern slope of the disposal embankment. A description and results of the test pit investigations along with the implications . of the results relative to the over . all dewatering effort are discussed in Sections 3 through 5. Installation and performance of the 17-well dewatering system were previously described in` the ``StatusReport onmore » Dewatering of Disposal Embankment`` issued in September, 1989. Additional studies are still on-going and are described in Section 6. Laboratory analysis continues on samples taken from the test pits. TAC`s characterization of the hydrogeological conditions at the Durango site is also proceeding. Results of these studies will be presented in subsequent reports. Appendices A and B present construction details of the well point system, toe trench and holding pond. Appendix C summarizes the performance-of the 17 pumping wells prior to winter shutdown and provides information on pumping rates, drawdowns, and disposition of the wells. Appendix D outlines the chronology of the dewatering effort to date.« less

Experiments in DIII-D Toward Achieving Rapid Shutdown with Runaway Electron Suppression

NASA Astrophysics Data System (ADS)

Hollmann, E. M.

2009-11-01

For safe discharge shutdown in future large tokamaks in the event of an unavoidable disruption, it is important to develop rapid (˜ several ms)shutdown methods to avoid large runaway electron currents, which pose a serious threat to plasma facing components. Prevention of runaway current formation has been proposed by either increasing electron-electron collisionality with massive particle injection, or magnetically by using externally applied non-axisymmetric fields to increase radial diffusive losses of a runaway seed population. Experiments studying both approaches have been pursued in the DIII-D tokamak. For collisional suppression, three different rapid shutdown methods are being investigated: massive gas injection, massive shattered cryogenic pellet injection, and polystyrene shell pellet injection. First-of-kind demonstrations of fast shutdowns were produced by 3000 Torr-l (0.8-g) shattered D2 pellets and large, 10-mm diameter, 0.3-g polystyrene shell pellets filled with boron powder. The application of external magnetic perturbations shows promising preliminary results in suppressing seed runaway electrons, although lack of repeatability in the runaway seed term made these results challenging to interpret. Experiments have been performed to help understand how runaways form and are transported during rapid shutdown. These experiments confirm that the commonly used 0D loop voltage + Dreicer evaporation picture of runaway seed formation is not applicable here, with relativistic E > 0.5,MeV electrons forming before any external loop voltage appears. Present applications of 0D, 1D, and 2D models to the rapid shutdown and runaway confinement experiments, as well as preliminary extrapolations to ITER, will be discussed.

Coherent Doppler lidar for automated space vehicle, rendezvous, station-keeping and capture

NASA Technical Reports Server (NTRS)

Dunkin, James A.

1991-01-01

Recent advances in eye-safe, short wavelength solid-state lasers offer real potential for the development of compact, reliable, light-weight, efficient coherent lidar. Laser diode pumping of these devices has been demonstrated, thereby eliminating the need for flash lamp pumping, which has been a major drawback to the use of these lasers in space based applications. Also these lasers now have the frequency stability required to make them useful in coherent lidar, which offers all of the advantages of non-coherent lidar, but with the additional advantage that direct determination of target velocity is possible by measurement of the Doppler shift. By combining the Doppler velocity measurement capability with the inherent high angular resolution and range accuracy of lidar it is possible to construct Doppler images of targets for target motion assessment. A coherent lidar based on a Tm,Ho:YAG 2-micrometer wavelength laser was constructed and successfully field tested on atmospheric targets in 1990. This lidar incorporated an all solid state (laser diode pumped) master oscillator, in conjunction with a flash lamp pumped slave oscillator. Solid-state laser technology is rapidly advancing, and with the advent of high efficiency, high power, semiconductor laser diodes as pump sources, all-solid-state, coherent lidars are a real possibility in the near future. MSFC currently has a feasibility demonstration effort under way which will involve component testing, and preliminary design of an all-solid-state, coherent lidar for automatic rendezvous, and capture. This two year effort, funded by the Director's Discretionary Fund is due for completion in 1992.

Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

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

Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.

A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power plant sites was performed. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, and Vermont Yankee. The evaluation was divided into four components: Characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory A description of the on-site infrastructure at the shutdown sitesmore » An evaluation of the near-site transportation infrastructure and transportation experience at the shutdown sites An evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. The primary sources for the inventory of SNF and GTCC waste were the U.S. Department of Energy (DOE) spent nuclear fuel inventory database, industry publications such as StoreFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of on-site infrastructure and near-site transportation infrastructure and experience included information collected during site visits, information provided by managers at the shutdown sites, Facility Interface Data Sheets compiled for DOE in 2005, Services Planning Documents prepared for DOE in 1993 and 1994, industry publications such as Radwaste Solutions, and Google Earth. State staff, State Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative have participated in nine of the shutdown site visits. Every shutdown site was found to have at least one off-site transportation mode option for removing its SNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. Additional conclusions from this evaluation include: The 13 shutdown sites use designs from 4 different suppliers involving 11 different (horizontal and vertical) dry storage systems that would require the use of 9 different transportation cask designs to remove the SNF and GTCC waste from the shutdown sites. Although some changes to transportation certificates of compliance will be required, the SNF at the initial 9 shutdown sites (Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion) is in dual purpose dry storage canisters that can be transported, including a small amount of high-burnup fuel. Most sites indicated that 2-3 years of advance time would be required for its preparations before shipments could begin. Some sites could be ready in less time. As additional sites such as Fort Calhoun, Clinton, Quad Cities, Pilgrim, Oyster Creek, and Diablo Canyon shut down, these sites will be included in updates to the evaluation.« less

Health Informatics for Neonatal Intensive Care Units: An Analytical Modeling Perspective

PubMed Central

Mench-Bressan, Nadja; McGregor, Carolyn; Pugh, James Edward

2015-01-01

The effective use of data within intensive care units (ICUs) has great potential to create new cloud-based health analytics solutions for disease prevention or earlier condition onset detection. The Artemis project aims to achieve the above goals in the area of neonatal ICUs (NICU). In this paper, we proposed an analytical model for the Artemis cloud project which will be deployed at McMaster Children’s Hospital in Hamilton. We collect not only physiological data but also the infusion pumps data that are attached to NICU beds. Using the proposed analytical model, we predict the amount of storage, memory, and computation power required for the system. Capacity planning and tradeoff analysis would be more accurate and systematic by applying the proposed analytical model in this paper. Numerical results are obtained using real inputs acquired from McMaster Children’s Hospital and a pilot deployment of the system at The Hospital for Sick Children (SickKids) in Toronto. PMID:27170907

Wastewater reclamation and recharge: A water management strategy for Albuquerque

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

Gorder, P.J.; Brunswick, R.J.; Bockemeier, S.W.

1995-12-31

Approximately 61,000 acre-feet of the pumped water is annually discharged to the Rio Grande as treated wastewater. Albuquerque`s Southside Water Reclamation Plant (SWRP) is the primary wastewater treatment facility for most of the Albuquerque area. Its current design capacity is 76 million gallons per day (mgd), which is expected to be adequate until about 2004. A master plan currently is being prepared (discussed here in Wastewater Master Planning and the Zero Discharge Concept section) to provide guidelines for future expansions of the plant and wastewater infrastructure. Construction documents presently are being prepared to add ammonia and nitrogen removal capability tomore » the plant, as required by its new discharge permit. The paper discusses water management strategies, indirect potable reuse for Albuquerque, water quality considerations for indirect potable reuse, treatment for potable reuse, geohydrological aspects of a recharge program, layout and estimated costs for a conceptual reclamation and recharge system, and work to be accomplished under phase 2 of the reclamation and recharge program.« less

A Flexible Master Oscillator for a Thomson Scattering Pulse-Burst Laser System

NASA Astrophysics Data System (ADS)

den Hartog, D. J.; Young, W. C.

2015-11-01

A new master oscillator will be installed in the pulse-burst laser system used for high-rep-rate Thomson scattering on the MST experiment. This new master oscillator will enable pulse repetition rates up to 1 MHz, with the ability to program a burst of pulses with arbitrary and varying time separation between each pulse. In addition, the energy of each master oscillator pulse can be adjusted to compensate for gain variations in the power amplifier section of the laser system. This flexibility is accomplished by chopping a CW laser source with a high-bandwidth acousto-optic modulator (AOM). The laser source is a 1064 nm diode-pumped solid-state laser with continuous output power variable from 100 to 500 mW. The 2 mm diameter polarized beam is focused into the gallium phosphide crystal of the AOM, which deflects the beam by approximately 60 mrad. Beam deflection is controlled by a simple digital input pulse, and is capable of producing laser pulses of less than 20 ns width at repetition rates much greater than 1 MHz. These pulses from the output of the AOM will be collimated and propagated into the laser amplifier system, where they will be amplified to ~ 2 J/pulse and injected into the MST plasma. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Award Number DE-FC02-05ER54814, and by the National Science Foundation under Award Number PHY-0821899.

Simulation of Energy Savings in Automotive Coatings Processes

NASA Astrophysics Data System (ADS)

Gerini Romagnoli, Marco

Recently, the automakers have become more and more aware of the environmental and economic impact of their manufacturing processes. The paint shop is the largest energy user in a vehicle manufacturing plant, and one way to reduce costs and energy usage is the optimization of this area. This project aims at providing a tool to model and simulate a paint shop, in order to run and analyze some scenarios and case studies, helping to take strategic decisions. Analytical computations and real data were merged to build a tool that can be used by FCA for their Sterling Heights plant. Convection and conduction heat losses were modeled for the dip processes and the ovens. Thermal balances were used to compute the consumptions of booths, decks and ovens, while pump and fan energy consumptions were modeled for each sub-process. The user acts on a calendar, scheduling a year of production, and the model predicts the energy consumption of the paint shop. Five scenarios were run to test different conditions and the influence of scheduling on the energy consumption. Two different sets of production schedules have been evaluated, the first one fulfilling the production requirement in one shift of 10 hours, at high rate, the second one using two 7-hour-long shifts at medium production rate. It was found that the unit cost was minimized in the warmest months of spring and fall, and system shutdown was a crucial factor to reduce energy consumption. A fifth hypothetical scenario was run, with a 4 month continuous production and an 8 month total shutdown, which reduced the energy consumption to a half of the best realistic scenario. When the plant was run in a two-shifts configuration, the cost to coat a vehicle was found to be 29 with weekend shutdown, and 39 without. In the one-shift configuration, the cost was slightly higher, but the difference was less than 5%. While the fifth scenario showed a consistent reduction of the unit cost, inventory and logistic expenses deriving from the production strategy make this scenario almost impossible to realize. A sensitivity analysis was run on several parameters influencing the energy consumption of the paint shop, and the booths set point temperature was found to be the most significant factor.

The Experimental Breeder Reactor II seismic probabilistic risk assessment

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

Roglans, J; Hill, D J

1994-02-01

The Experimental Breeder Reactor II (EBR-II) is a US Department of Energy (DOE) Category A research reactor located at Argonne National Laboratory (ANL)-West in Idaho. EBR-II is a 62.5 MW-thermal Liquid Metal Reactor (LMR) that started operation in 1964 and it is currently being used as a testbed in the Integral Fast Reactor (IFR) Program. ANL has completed a Level 1 Probabilistic Risk Assessment (PRA) for EBR-II. The Level 1 PRA for internal events and most external events was completed in June 1991. The seismic PRA for EBR-H has recently been completed. The EBR-II reactor building contains the reactor, themore » primary system, and the decay heat removal systems. The reactor vessel, which contains the core, and the primary system, consisting of two primary pumps and an intermediate heat exchanger, are immersed in the sodium-filled primary tank, which is suspended by six hangers from a beam support structure. Three systems or functions in EBR-II were identified as the most significant from the standpoint of risk of seismic-induced fuel damage: (1) the reactor shutdown system, (2) the structural integrity of the passive decay heat removal systems, and (3) the integrity of major structures, like the primary tank containing the reactor that could threaten both the reactivity control and decay heat removal functions. As part of the seismic PRA, efforts were concentrated in studying these three functions or systems. The passive safety response of EBR-II reactor -- both passive reactivity shutdown and passive decay heat removal, demonstrated in a series of tests in 1986 -- was explicitly accounted for in the seismic PRA as it had been included in the internal events assessment.« less

Static Stress Transfers Causes Delayed Seismicity Shutdown

NASA Astrophysics Data System (ADS)

Kroll, K.; Richards-Dinger, K. B.; Dieterich, J. H.; Cochran, E. S.

2015-12-01

It has been long debated what role static stress changes play in the enhancement and suppression of seismicity in the near-field region of large earthquakes. While numerous observations have correlated earthquake triggering and elevated seismicity rates with regions of increased Coulomb failure stress (CFS), observations of seismic quiescence in stress shadow regions are more controversial. When observed, seismicity shutdowns are often delayed by days to months following a negative stress perturbation. Some studies propose that the delay in the seismic shutdown can be caused by rupture promoting failure on one fault type while suppressing activity on another; thus the observed seismicity reflects the weighted contribution of the two faulting populations. For example, it was noted that in the 75 years following the 1906 San Francisco earthquake, strike-slip faulting earthquakes were inhibited, while thrust faulting events were promoted. However, definitive observations supporting this delayed shutdown mechanism are rare. In this study, we report seismicity rate increases and decreases that correlate with regions of Coulomb stress transfer, and show observations of a delayed shutdown in the Yuha Desert, California. We use a Coulomb stress change model coupled with a rate-and state- earthquake model to show that the delay in the shutdown is due to the combined changes in the rates of normal and strike-slip faulting events following the 2010 M5.72 Ocotillo aftershock of the 2010 El Mayor-Cucapah earthquake.

Startup, Shutdown, & Malfunction (SSM) Emissions

EPA Pesticide Factsheets

EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

NUMBER AND TYPE OF OPERATING CYCLES FOR THE FFTF

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

Boyd, D. C.

1969-05-15

The choice of materials and other vessel design decisions necessary to provide the desired life expectancy for the FTR vessel are partially dependent upon estimates of the number and type of reactor shutdowns and startups which may be anticipated. Current estimates of these so-called "cycles" are given, including scram frequency, experimental outage frequency, standard shutdowns and startups, and rapid controlled shutdowns. Also discussed are abnormal heatup or cooldown, and tentative goals for temperature controls. MTR, ETR, and typical PRTR operating histories are tabulated.

Task 4 completion report for 40 Kilowatt grid connected modification contract

NASA Technical Reports Server (NTRS)

Vogt, J. H.

1983-01-01

Startup, operation in grid connect mode, shutdown from grid connects, operation in isolated mode, shutdown from isolated mode, steady state operation, mode transfers, and voltage disconnects are addressed.

75 FR 33220 - Extension of Public Comment Period for Proposed Rule on the Approval and Promulgation of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-11

...; Excess Emissions During Startup, Shutdown, Maintenance, and Malfunction Activities AGENCY: Environmental...; Texas; Excess Emissions During Startup, Shutdown, Maintenance, and Malfunction Activities.'' As...

Boronization on NSTX using Deuterated Trimethylboron

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

W.R. Blanchard; R.C. Gernhardt; H.W. Kugel

2002-01-28

Boronization on the National Spherical Torus Experiment (NSTX) has proved to be quite beneficial with increases in confinement and density, and decreases in impurities observed in the plasma. The boron has been applied to the interior surfaces of NSTX, about every 2 to 3 weeks of plasma operation, by producing a glow discharge in the vacuum vessel using deuterated trimethylboron (TMB) in a 10% mixture with helium. Special NSTX requirements restricted the selection of the candidate boronization method to the use of deuterated boron compounds. Deuterated TMB met these requirements, but is a hazardous gas and special care in themore » execution of the boronization process is required. This paper describes the existing GDC, Gas Injection, and Torus Vacuum Pumping System hardware used for this process, the glow discharge process, and the automated control system that allows for remote operation to maximize both the safety and efficacy of applying the boron coating. The administrative requirements and the detailed procedure for the setup, operation and shutdown of the process are also described.« less

The potential for health risks from intrusion of contaminants into the distribution system from pressure transients.

PubMed

LeChevallier, Mark W; Gullick, Richard W; Karim, Mohammad R; Friedman, Melinda; Funk, James E

2003-03-01

The potential for public health risks associated with intrusion of contaminants into water supply distribution systems resulting from transient low or negative pressures is assessed. It is shown that transient pressure events occur in distribution systems; that during these negative pressure events pipeline leaks provide a potential portal for entry of groundwater into treated drinking water; and that faecal indicators and culturable human viruses are present in the soil and water exterior to the distribution system. To date, all observed negative pressure events have been related to power outages or other pump shutdowns. Although there are insufficient data to indicate whether pressure transients are a substantial source of risk to water quality in the distribution system, mitigation techniques can be implemented, principally the maintenance of an effective disinfectant residual throughout the distribution system, leak control, redesign of air relief venting, and more rigorous application of existing engineering standards. Use of high-speed pressure data loggers and surge modelling may have some merit, but more research is needed.

SP-100 multimegawatt scaleup to meet electric propulsion mission requirements

NASA Astrophysics Data System (ADS)

Newkirk, D. W.; Salamah, S. A.; Stewart, S. L.; Pluta, P. R.

The SP-100 nuclear heat source technology, utilizing uranium nitride fuel clad in PWC-11 in a fast reactor with lithium coolant circulated by an electromagnetic pump, is shown to be directly extrapolatable to thermal power levels that meet NASA nuclear electric propulsion requirements using different power conversion techniques. The SP-100 nuclear technology can be applied to missions with NEP (nuclear electric propulsion) requirements as low as tens of kWe to tens of MWe. It is pointed out that the SP-100 heat source has a great advantage of very long lifetime capability, since it utilizes very rugged refractory metal fuel pins and is independent of the power conversion scheme chosen for a given mission. The only moving parts in the nuclear subsystems are the control rods moved to compensate for fuel enrichment degradation due to fission and for power shutdown. Lowest alpha values in the range of interest for potential NASA missions are predicted for the dynamic Rankine and static HYTEC conversion systems.

Operational Experience with the Internal Thermal Control System Dual-Membrane Gas Trap

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Lukens, Clark; Reeves, Daniel R.; Holt, James M.

2003-01-01

A dual-membrane gas trap is currently used to remove non-condensed gases (NCG) from the Internal Thermal Control System (ITCS) coolant on board the International Space Station. The gas trap consists of concentric tube membrane pairs, comprised of outer hydrophilic tubes and inner hydrophobic fibers. Liquid coolant passes through the outer hydrophilic membrane, which traps the NCG. The inner hydrophobic fiber allows the trapped NCG to pass through and vent to the ambient atmosphere in the cabin. The purpose of the gas trap is to prevent gas bubbles from causing depriming, overspeed, and shutdown of the ITCS pump, and the current gas trap has performed flawlessly in this regard. However, because of actual operational conditions on-orbit, its gas removal performance and operational lifetime have been affected. This paper discusses experiences with several of these dual- membrane gas traps, including on-orbit gas venting rate, effects due to the presence of nickel in the ITCS coolant, and subsequent refurbishing to remove the nickel from the gas trap.

Inherently Safe Fission Power System for Lunar Outposts

NASA Astrophysics Data System (ADS)

Schriener, Timothy M.; El-Genk, Mohamed S.

2013-09-01

This paper presents the Solid Core-Sectored Compact Reactor (SC-SCoRe) and power system for future lunar outposts. The power system nominally provides 38 kWe continuously for 21 years, employs static components and has no single point failures in reactor cooling or power generation. The reactor core has six sectors, each has a separate pair of primary and secondary loops with liquid NaK-56 working fluid, thermoelectric (TE) power conversion and heat-pipes radiator panels. The electromagnetic (EM) pumps in the primary and secondary loops, powered with separate TE power units, ensure operation reliability and passive decay heat removal from the reactor after shutdown. The reactor poses no radiological concerns during launch, and remains sufficiently subcritical, with the radial reflector dissembled, when submerged in wet sand and the core flooded with seawater, following a launch abort accident. After 300 years of storage below grade on the Moon, the total radioactivity in the post-operation reactor drops below 164 Ci, a low enough radioactivity for a recovery and safe handling of the reactor.

Shuttle avionics software trials, tribulations and success

NASA Technical Reports Server (NTRS)

Henderson, O. L.

1985-01-01

The early problems and the solutions developed to provide the required quality software needed to support the space shuttle engine development program are described. The decision to use a programmable digital control system on the space shuttle engine was primarily based upon the need for a flexible control system capable of supporting the total engine mission on a large complex pump fed engine. The mission definition included all control phases from ground checkout through post shutdown propellant dumping. The flexibility of the controller through reprogrammable software allowed the system to respond to the technical challenges and innovation required to develop both the engine and controller hardware. This same flexibility, however, placed a severe strain on the capability of the software development and verification organization. The overall development program required that the software facility accommodate significant growth in both the software requirements and the number of software packages delivered. This challenge was met by reorganization and evolution in the process of developing and verifying software.

Sub-nanosecond lasers for cosmetics and dermatology

NASA Astrophysics Data System (ADS)

Tarasov, Aleksandr A.; Chu, Hong

2018-02-01

We report about the development of two new subnanosecond solid-state laser models for application in dermatology and cosmetics. One model uses subnanosecond Nd: YAG microchip laser as a master oscillator and includes Nd: YAG double- and single-pass amplifiers. At 10 Hz this laser produces more than 600 mJ pulse energy with duration 500 +/- 5 ps. Another model (under development) is gain-switched Ti: Sapphire laser with short cavity. This laser produces 200 mJ, 560 ps pulses at 790 nm and uses standard Q-Switched Nd: YAG laser with nanosecond pulse duration as a pumping sourse.

Spectral dynamics of square pulses in passively mode-locked fiber lasers

NASA Astrophysics Data System (ADS)

Semaan, Georges; Komarov, Andrey; Niang, Alioune; Salhi, Mohamed; Sanchez, François

2018-02-01

We investigate experimentally and numerically the spectral dynamics of square pulses generated in passively mode-locked fiber lasers under the dissipative soliton resonance. The features of the transition from the single-peak spectral profile to the doublet spectrum with increasing pump power are studied. The used master equation takes into account the gain saturation, the quadratic frequency dispersion of the gain and the refractive index, and the cubic-quintic nonlinearity of the losses and refractive index. Experimental data are obtained for an Er:Yb-doped fiber ring laser. The theoretical and experimental results are in good agreement with each other.

Optimisation of frequency-modulated characteristics of output radiation in a lidar with Raman amplification

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

Grigorievsky, V I; Tezadov, Ya A

2016-03-31

The reported study is aimed at increasing the power in the transmission path of a lidar with Raman amplification for longpath sensing of methane by optimising the frequency-modulated characteristics of the output radiation. The pump current of the used distributed-feedback master laser was modulated by a linearfrequency signal with simultaneous application of a non-synchronous high-frequency signal. For such a modulation regime, the Raman amplifier provided the mean output power of 2.5 W at a wavelength of 1650 nm. The spectral broadening did not significantly decrease the lidar sensitivity at long paths. (lidars)

Startup, Shutdown, & Malfunction (SSM) Emissions at Industrial Facilities

EPA Pesticide Factsheets

EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

1.6  MW peak power, 90  ps all-solid-state laser from an aberration self-compensated double-passing end-pumped Nd:YVO₄ rod amplifier.

PubMed

Wang, Chunhua; Liu, Chong; Shen, Lifeng; Zhao, Zhiliang; Liu, Bin; Jiang, Hongbo

2016-03-20

In this paper a delicately designed double-passing end-pumped Nd:YVO₄ rod amplifier is reported that produces 10.2 W average laser output when seeded by a 6 mW Nd:YVO₄ microchip laser at a repetition rate of 70 kHz with pulse duration of 90 ps. A pulse peak power of ∼1.6  MW and pulse energy of ∼143  μJ is achieved. The beam quality is well preserved by a double-passing configuration for spherical-aberration compensation. The laser-beam size in the amplifier is optimized to prevent the unwanted damage from the high pulse peak-power density. This study provides a simple and robust picosecond all-solid-state master oscillator power amplifier system with both high peak power and high beam quality, which shows great potential in the micromachining.

The interplay between HIF-1 and calcium signalling in cancer.

PubMed

Azimi, Iman

2018-04-01

The interplay between hypoxia-inducible factor-1 (HIF-1) and calcium in cancer has begun to be unravelled with recent findings demonstrating the relationships between the two in different cancer types. This is an area of significance considering the crucial roles of both HIF-1 and calcium signalling in cancer progression and metastasis. This review summarises the experimental evidence of the crosstalk between HIF-1 and specific calcium channels, pumps and regulators in the context of cancer. HIF-1 as a master regulator of hypoxic transcriptional responses, mediates transcription of several calcium modulators. On the other hand, specific calcium channels and pumps regulate HIF-1 activity through controlling its transcription, translation, stabilisation, or nuclear translocation. Identifying the interplay between HIF-1 and components of the calcium signal will give new insights into mechanisms underlying cellular responses to physiological and pathophysiological cues, and may provide novel and more efficient therapeutic strategies for the control of cancer progression. Copyright © 2018 Elsevier Ltd. All rights reserved.

Widely wavelength tunable gain-switched Er³⁺-doped ZBLAN fiber laser around 2.8 μm.

PubMed

Wei, Chen; Luo, Hongyu; Shi, Hongxia; Lyu, YanJia; Zhang, Han; Liu, Yong

2017-04-17

In this paper, we demonstrate a wavelength widely tunable gain-switched Er³⁺-doped ZBLAN fiber laser around 2.8 μm. The laser can be tuned over 170 nm (2699 nm~2869.9 nm) for various pump power levels, while maintaining stable μs-level single-pulse gain-switched operation with controllable output pulse duration at a selectable repetition rate. To the best of our knowledge, this is the first wavelength tunable gain-switched fiber laser in the 3 μm spectral region with the broadest tuning range (doubling the record tuning range) of the pulsed fiber lasers around 3 μm. Influences of pump energy and power on the output gain-switched laser performances are investigated in detail. This robust, simple, and versatile mid-infrared pulsed fiber laser source is highly suitable for many applications including laser surgery, material processing, sensing, spectroscopy, as well as serving as a practical seed source in master oscillator power amplifiers.

Staged venting of fuel cell system during rapid shutdown

DOEpatents

Clingerman, Bruce J.; Doan, Tien M.; Keskula, Donald H.

2002-01-01

A venting methodology and system for rapid shutdown of a fuel cell apparatus of the type used in a vehicle propulsion system. H.sub.2 and air flows to the fuel cell stack are slowly bypassed to the combustor upon receipt of a rapid shutdown command. The bypass occurs over a period of time (for example one to five seconds) using conveniently-sized bypass valves. Upon receipt of the rapid shutdown command, the anode inlet of the fuel cell stack is instantaneously vented to a remote vent to remove all H.sub.2 from the stack. Airflow to the cathode inlet of the fuel cell stack gradually diminishes over the bypass period, and when the airflow bypass is complete the cathode inlet is also instantaneously vented to a remote vent to eliminate pressure differentials across the stack.

Staged venting of fuel cell system during rapid shutdown

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2004-09-14

A venting methodology and system for rapid shutdown of a fuel cell apparatus of the type used in a vehicle propulsion system. H.sub.2 and air flows to the fuel cell stack are slowly bypassed to the combustor upon receipt of a rapid shutdown command. The bypass occurs over a period of time (for example one to five seconds) using conveniently-sized bypass valves. Upon receipt of the rapid shutdown command, the anode inlet of the fuel cell stack is instantaneously vented to a remote vent to remove all H.sub.2 from the stack. Airflow to the cathode inlet of the fuel cell stack gradually diminishes over the bypass period, and when the airflow bypass is complete the cathode inlet is also instantaneously vented to a remote vent to eliminate pressure differentials across the stack.

Analysis of activation and shutdown contact dose rate for EAST neutral beam port

NASA Astrophysics Data System (ADS)

Chen, Yuqing; Wang, Ji; Zhong, Guoqiang; Li, Jun; Wang, Jinfang; Xie, Yahong; Wu, Bin; Hu, Chundong

2017-12-01

For the safe operation and maintenance of neutral beam injector (NBI), specific activity and shutdown contact dose rate of the sample material SS316 are estimated around the experimental advanced superconducting tokamak (EAST) neutral beam port. Firstly, the neutron emission intensity is calculated by TRANSP code while the neutral beam is co-injected to EAST. Secondly, the neutron activation and shutdown contact dose rates for the neutral beam sample materials SS316 are derived by the Monte Carlo code MCNP and the inventory code FISPACT-2007. The simulations indicate that the primary radioactive nuclides of SS316 are 58Co and 54Mn. The peak contact dose rate is 8.52 × 10-6 Sv/h after EAST shutdown one second. That is under the International Thermonuclear Experimental Reactor (ITER) design values 1 × 10-5 Sv/h.

Dioxins from medical waste incineration: Normal operation and transient conditions.

PubMed

Chen, Tong; Zhan, Ming-xiu; Yan, Mi; Fu, Jian-ying; Lu, Sheng-yong; Li, Xiao-dong; Yan, Jian-hua; Buekens, Alfons

2015-07-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are key pollutants in waste incineration. At present, incinerator managers and official supervisors focus only on emissions evolving during steady-state operation. Yet, these emissions may considerably be raised during periods of poor combustion, plant shutdown, and especially when starting-up from cold. Until now there were no data on transient emissions from medical (or hospital) waste incineration (MWI). However, MWI is reputed to engender higher emissions than those from municipal solid waste incineration (MSWI). The emission levels in this study recorded for shutdown and start-up, however, were significantly higher: 483 ± 184 ng Nm(-3) (1.47 ± 0.17 ng I-TEQ Nm(-3)) for shutdown and 735 ng Nm(-3) (7.73 ng I-TEQ Nm(-3)) for start-up conditions, respectively. Thus, the average (I-TEQ) concentration during shutdown is 2.6 (3.8) times higher than the average concentration during normal operation, and the average (I-TEQ) concentration during start-up is 4.0 (almost 20) times higher. So monitoring should cover the entire incineration cycle, including start-up, operation and shutdown, rather than optimised operation only. This suggestion is important for medical waste incinerators, as these facilities frequently start up and shut down, because of their small size, or of lacking waste supply. Forthcoming operation should shift towards much longer operating cycles, i.e., a single weekly start-up and shutdown. © The Author(s) 2015.

Improved refractory performance through partnership

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

Linck, F.E.; Peters, D.

1995-12-31

From the early designs and construction of Circulating Fluidized Bed (CFB) boilers, many improvements have been made based upon observations of performance. Included in these improvements have been the refractory linings. The early refractory linings were subjected to extreme fluctuations in temperatures as the units experienced up and down conditions. As the designs were improved refractory failures were mostly due to the operating conditions and other mechanical stresses rather than continual shutdowns and startups. More recent problems observed with refractory linings are localized areas of high erosion, corrosion and cracking which result in hot spots and eventual shutdowns for repair.more » Today the objective of refractory suppliers and installers is to strive towards planned shutdowns rather than emergency shutdowns. This can be accomplished through partnerships between operations, material suppliers and installers. In essence, the concept is a cooperative effort between these groups to solve the variety of refractory problems in order to achieve longer refractory lining performance and less chance for emergency shutdowns. The reliability of the refractory lining is dependent on the successful combination of the material selected, proper design and the installation of the refractory material. Where these three elements combine, the lining has the best chance of performing its intended purpose.« less

40 CFR 63.6105 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... to you at all times except during startup, shutdown, and malfunctions. (b) If you must comply with... times including during startup, shutdown, and malfunction. Testing and Initial Compliance Requirements ...

Shutdown system for a nuclear reactor

DOEpatents

Groh, E.F.; Olson, A.P.; Wade, D.C.; Robinson, B.W.

1984-06-05

An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion. 8 figs.

Shutdown system for a nuclear reactor

DOEpatents

Groh, Edward F.; Olson, Arne P.; Wade, David C.; Robinson, Bryan W.

1984-01-01

An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion.

Time-to-burnout data for a prototypical ITER divertor tube during a simulated loss of flow accident

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

Marshall, T.D.; Watson, R.D.; McDonald, J.M.

The Loss of Flow Accident (LOFA) is a serious safety concern for the International Thermonuclear Experimental Reactor (ITER) as it has been suggested that greater than 100 seconds are necessary to safely shutdown the plasma when ITER is operating at full power. In this experiment, the thermal response of a prototypical ITER divertor tube during a simulated LOFA was studied. The divertor tube was fabricated from oxygen-free high-conductivity copper to have a square geometry with a circular coolant channel. The coolant channel inner diameter was 0.77 cm, the heated length was 4.0 cm, and the heated width was 1.6 cm.more » The mockup did not feature any flow enhancement techniques, i.e., swirl tape, helical coils, or internal fins. One-sided surface heating of the mockup was accomplished through the use of the 30 kW Sandia Electron Beam Test System. After reaching steady state temperatures in the mockup, as determined by two Type-K thermocouples installed 0.5 mm beneath the heated surface, the coolant pump was manually tripped off and the coolant flow allowed to naturally coast down. Electron beam heating continued after the pump trip until the divertor tube`s heated surface exhibited the high temperature transient normally indicative of rapidly approaching burnout. Experimental data showed that time-to-burnout increases proportionally with increasing inlet velocity and decreases proportionally with increasing incident heat flux.« less

Design and Fabrication of a 5-kWe Free-Piston Stirling Power Conversion System

NASA Technical Reports Server (NTRS)

Chapman, Peter A.; Walter, Thomas J.; Brandhorst, Henry W., Jr.

2008-01-01

Progress in the design and fabrication of a 5-kWe free-piston Stirling power conversion system is described. A scaled-down version of the successful 12.5-kWe Component Test Power Converter (CTPC) developed under NAS3-25463, this single cylinder prototype incorporates cost effective and readily available materials (steel versus beryllium) and components (a commercial linear alternator). The design consists of a displacer suspended on internally pumped gas bearings and a power piston/alternator supported on flexures. Non-contacting clearance seals are used between internal volumes. Heat to and from the prototype is supplied via pumped liquid loops passing through shell and tube heat exchangers. The control system incorporates several novel ideas such as a pulse start capability and a piston stroke set point control strategy that provides the ability to throttle the engine to match the required output power. It also ensures stable response to various disturbances such as electrical load variations while providing useful data regarding the position of both power piston and displacer. All design and analysis activities are complete and fabrication is underway. Prototype test is planned for summer 2008 at Foster-Miller to characterize the dynamics and steady-state operation of the prototype and determine maximum power output and system efficiency. Further tests will then be performed at Auburn University to determine start-up and shutdown characteristics and assess transient response to temperature and load variations.

Development of the Next Generation Gas Trap for the Space Station Internal Thermal Control System

NASA Technical Reports Server (NTRS)

Leimkuehler, Thomas O.; Spelbring, Chris; Reeves, Daniel R.; Holt, James M.

2003-01-01

The current dual-membrane gas trap is designed to remove non-condensed gases (NCG) from the Internal Thermal Control System (ITCS) coolant on board the International Space Station (ISS). To date it has successfully served its purpose of preventing depriming, overspeed, and shutdown of the ITCS pump. However, contamination in the ITCS coolant has adversely affected the gas venting rate and lifetime of the gas trap, warranting a development effort for a next-generation gas trap. Design goals are to meet or exceed the current requirements to (1) include greater operating ranges and conditions, (2) eliminate reliance on the current hydrophilic tube fabrication process, and (3) increase operational life and tolerance to particulate and microbial growth fouling. In addition, the next generation gas trap will essentially be a 'dropin" design such that no modifications to the ITCS pump package assembly (PPA) will be required, and the implementation of the new design will not affect changes to the ITCS operational conditions, interfaces, or software. This paper will present the initial membrane module design and development work which has included (1) a trade study among several conceptual designs, (2) performance modeling of a hydrophobic-only design, and (3) small-scale development test data for the hydrophobic-only design. Testing has shown that the hydrophobic-only design is capable of performing even better than the current dual-membrane design for both steady-state gas removal and gas slug removal.

40 CFR 62.14413 - When do the emission limits and stack opacity requirements apply?

Code of Federal Regulations, 2011 CFR

2011-07-01

... all times except during periods of startup, shutdown, or malfunction, provided that no hospital waste or medical/infectious waste is charged to your HMIWI during periods of startup, shutdown, or...

40 CFR 62.14413 - When do the emission limits and stack opacity requirements apply?

Code of Federal Regulations, 2012 CFR

2012-07-01

... all times except during periods of startup, shutdown, or malfunction, provided that no hospital waste or medical/infectious waste is charged to your HMIWI during periods of startup, shutdown, or...

40 CFR 62.14413 - When do the emission limits and stack opacity requirements apply?

Code of Federal Regulations, 2010 CFR

2010-07-01

... all times except during periods of startup, shutdown, or malfunction, provided that no hospital waste or medical/infectious waste is charged to your HMIWI during periods of startup, shutdown, or...

Miniature Heat Transport System for Nanosatellite Technology

NASA Technical Reports Server (NTRS)

Douglas, Donya M,

1999-01-01

The scientific understanding of key physical processes between the Sun and the Earth require simultaneous measurements from many vantage points in space. Nano-satellite technologies will enable a class of constellation missions for the NASA Space Science Sun-Earth Connections. This recent emphasis on the implementation of smaller satellites leads to a requirement for development of smaller subsystems in several areas. Key technologies under development include: advanced miniaturized chemical propulsion; miniaturized sensors; highly integrated, compact electronics; autonomous onboard and ground operations; miniatures low power tracking techniques for orbit determination; onboard RF communications capable of transmitting data to the ground from far distances; lightweight efficient solar array panels; lightweight, high output battery cells; lightweight yet strong composite materials for the nano-spacecraft and deployer-ship structures. These newer smaller systems may have higher power densities and higher thermal transport requirements than seen on previous small satellites. Furthermore, the small satellites may also have a requirement to maintain thermal control through extended earth shadows, possibly up to 8 hours long. Older thermal control technology, such as heaters, thermostats, and heat pipes, may not be sufficient to meet the requirements of these new systems. Conversely, a miniature two-phase heat transport system (Mini-HTS) such as a Capillary Pumped Loop (CPL) or Loop Heat Pipe (LBP) is a viable alternative. A Mini-HTS can provide fine temperature control, thermal diode action, and a highly efficient means of heat transfer. The Mini-HTS would have power capabilities in the range of tens of watts or less and provide thermal control over typical spacecraft ranges. The Mini-HTS would allow the internal portion of the spacecraft to be thermally isolated from the external radiator, thus protecting the internal components from extreme cold temperatures during an eclipse. The Mini-HTS would transport the beat from these components to a radiator during their operational modes, and it would be shutdown during non-operational or eclipse modes. Shutdown of the Mini-HTS would be accomplished with small heaters and has been successfully demonstrated on numerous occasions, both in the lab and on flight experiments. Efforts are now underway to miniaturize two-phase heat transport systems for the Nanosatellite project, with potential application to other small satellite programs. 'ne goal of this project is to design, build, and test miniature heat transport systems (MHTS) that would demonstrate the feasibility of a small Capillary Pumped Loop (CPL) or Loop Heat Pipe (LBP).

Tunable femtosecond lasers with low pump thresholds

NASA Astrophysics Data System (ADS)

Oppo, Karen

The work in this thesis is concerned with the development of tunable, femtosecond laser systems, exhibiting low pump threshold powers. The main motive for this work was the development of a low threshold, self-modelocked Ti:Al2O3 laser in order to replace the conventional large-frame argon-ion pump laser with a more compact and efficient all-solid-state alternative. Results are also presented for an all-solid-state, self-modelocked Cr:LiSAF laser, however most of this work is concerned with self-modelocked Ti:Al2O3 laser systems. In chapter 2, the operation of a regeneratively-initiated, and a hard-aperture self- modelocked Ti:Al2O3 laser, pumped by an argon-ion laser, is discussed. Continuous- wave oscillation thresholds as low as 160mW have been demonstrated, along with self-modelocked threshold powers as low as 500mW. The measurement and suppression of phase noise on modelocked lasers is discussed in chapter 3. This is followed by a comparison of the phase noise characteristics of the regeneratively-initiated, and hard-aperture self-modelocked Ti:Al2O3 lasers. The use of a synchronously-operating, high resolution electron-optical streak camera in the evaluation of timing jitter is also presented. In chapter 4, the construction and self-modelocked operation of an all-solid-state Ti:Al2O3 laser is described. The all-solid-state alternative to the conventional argon-ion pump laser was a continuous-wave, intracavity-frequency doubled, diode-laser pumped Nd:YLF ring laser. At a total diode-laser pump power of 10W, this minilaser was capable of producing a single frequency output of 1W, at 523.5nm in a TEM00 beam. The remainder of this thesis looks at the operation of a self-modelocked Ti:Al2O3 laser generating ultrashort pulses at wavelengths as long as 1053nm. The motive for this work was the development of an all-solid-state, self- modelocked Ti:Al2O3 laser operating at 1053nm, for use as a master oscillator in a Nd:glass power chain.

Display-And-Alarm Circuit For Accelerometer

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Compact accelerometer assembly consists of commercial accelerometer retrofit with display-and-alarm circuit. Provides simple means for technician attending machine to monitor vibrations. Also simpifies automatic safety shutdown by providing local alarm or shutdown signal when vibration exceeds preset level.

78 FR 18564 - Reserve Forces Policy Board (RFPB); Notice of Cancellation and Rescheduling of Federal Advisory...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

....m. in the Pentagon. Due to weather conditions and a federal government shutdown, the scheduled March... weather conditions and a federal government shutdown, the scheduled March 6, 2013 Board meeting is...

40 CFR 63.6105 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... limitations which apply to you at all times except during startup, shutdown, and malfunctions. (b) If you must... emissions at all times including during startup, shutdown, and malfunction. Testing and Initial Compliance...

40 CFR 63.6105 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... limitations which apply to you at all times except during startup, shutdown, and malfunctions. (b) If you must... emissions at all times including during startup, shutdown, and malfunction. Testing and Initial Compliance...

40 CFR 63.6105 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... limitations which apply to you at all times except during startup, shutdown, and malfunctions. (b) If you must... emissions at all times including during startup, shutdown, and malfunction. Testing and Initial Compliance...

Two-mode mazer injected with V-type three-level atoms

NASA Astrophysics Data System (ADS)

Liang, Wen-Qing; Zhang, Zhi-Ming; Xie, Sheng-Wu

2003-12-01

The properties of the two-mode mazer operating on V-type three-level atoms are studied. The effect of the one-atom pumping on the two modes of the cavity field in number-state is asymmetric, that is, the atom emits a photon into one mode with some probability and absorbs a photon from the other mode with some other probability. This effect makes the steady-state photon distribution and the steady-state photon statistics asymmetric for the two modes. The diagram of the probability currents for the photon distribution, given by the analysis of the master equation, reveals that there is no detailed balance solution for the master equation. The computations show that the photon statistics of one mode or both modes can be sub-Poissonian, that the two modes can have anticorrelation or correlation, that the photon statistics increases with the increase of thermal photons and that the resonant position and strength of the photon statistics are influenced by the ratio of the two coupling strengths of the two modes. These properties are also discussed physically.

40 CFR 63.11496 - What are the standards and compliance requirements for process vents?

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Startup, shutdown, malfunction (SSM). Section 63.998(b)(2)(iii),(b)(6)(i)(A), and (d)(3) do not apply for.... (i) Startup, shutdown, and malfunction (SSM). References to SSM provisions in subparts that are...

40 CFR 63.11496 - What are the standards and compliance requirements for process vents?

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Startup, shutdown, malfunction (SSM). Section 63.998(b)(2)(iii),(b)(6)(i)(A), and (d)(3) do not apply for.... (i) Startup, shutdown, and malfunction (SSM). References to SSM provisions in subparts that are...

40 CFR 63.11496 - What are the standards and compliance requirements for process vents?

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Startup, shutdown, malfunction (SSM). Section 63.998(b)(2)(iii),(b)(6)(i)(A), and (d)(3) do not apply for.... (i) Startup, shutdown, and malfunction (SSM). References to SSM provisions in subparts that are...

40 CFR 63.9610 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... section at all times, except during periods of startup, shutdown, and malfunction. The terms startup... develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). [68...

Buffer thermal energy storage for a solar Brayton engine

NASA Technical Reports Server (NTRS)

Strumpf, H. J.; Barr, K. P.

1981-01-01

A study has been completed on the application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine. To aid in the study, a computer program was written for complete transient/stead-state Brayton cycle performance. The results indicated that thermal storage can afford a significant decrease in the number of engine shutdowns as compared to operating without thermal storage. However, the number of shutdowns does not continuously decrease as the storage material weight increases. In fact, there appears to be an optimum weight for minimizing the number of shutdowns.

Confirmation of shutdown cooling effects

NASA Astrophysics Data System (ADS)

Sato, Kotaro; Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro

2015-12-01

After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO2 fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO2 and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

Shutdown-induced tensile stress in monolithic miniplates as a possible cause of plate pillowing at very high burnup

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

Medvedev, Pavel G; Ozaltun, Hakan; Robinson, Adam Brady

2014-04-01

Post-irradiation examination of Reduced Enrichment for Research and Test Reactors (RERTR)-12 miniplates showed that in-reactor pillowing occurred in at least 4 plates, rendering performance of these plates unacceptable. To address in-reactor failures, efforts are underway to define the mechanisms responsible for in-reactor pillowing, and to suggest improvements to the fuel plate design and operational conditions. To achieve these objectives, the mechanical response of monolithic fuel to fission and thermally-induced stresses was modeled using a commercial finite element analysis code. Calculations of stresses and deformations in monolithic miniplates during irradiation and after the shutdown revealed that the tensile stress generated inmore » the fuel increased from 2 MPa to 100 MPa at shutdown. The increase in tensile stress at shutdown possibly explains in-reactor pillowing of several RERTR-12 miniplates irradiated to the peak local burnup of up to 1.11x1022 fissions/cm3 . This paper presents the modeling approach and calculation results, and compares results with post-irradiation examinations and mechanical testing of irradiated fuel. The implications for the safe use of the monolithic fuel in research reactors are discussed, including the influence of fuel burnup and power on the magnitude of the shutdown-induced tensile stress.« less

Study on regional air quality impact from a chemical plant emergency shutdown.

PubMed

Ge, Sijie; Wang, Sujing; Xu, Qiang; Ho, Thomas

2018-06-01

Emergency shutdowns of chemical plants (ESCP) inevitably generate intensive and huge amounts of VOCs and NO x emissions through flaring that can cause highly localized and transient air pollution events with elevated ozone concentrations. However, quantitative studies of regional ozone impact due to ESCP, in terms of how ESCP would affect and to what extent ESCP could impact, are still lacking. This paper reports a systematic study on regional air quality impact from an olefin plant emergency shutdown due to the sudden failure of its cracked gas compressor (CGC). It demonstrates that emergency shutdown may cause significant ozone increment subject to different factors such as the starting time of emergency shutdown, flare destruction and removal efficiency (DRE) and plant location. In our studied case, the 8-hr ozone increment ranges from 0.4 to 3.3 ppb under different starting time, from 3.3 to 24.8 ppb under different DRE, and from 1.6 to 3.3 ppb under different locations. The results enable us to understand how and to what extent emergency operating activities of the chemical process will affect local air quality, which might be beneficial for decision makings on emergency air-quality response and control in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

33 CFR 127.205 - Emergency shutdown.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Equipment § 127.205 Emergency shutdown. Each transfer... automatically when the fixed sensors under § 127.201(b) measure LNG concentrations exceeding 40% of the lower...

33 CFR 127.205 - Emergency shutdown.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Equipment § 127.205 Emergency shutdown. Each transfer... automatically when the fixed sensors under § 127.201(b) measure LNG concentrations exceeding 40% of the lower...

Despite the Shutdown, Rescheduled NIH Research Festival Brings Science to the Forefront | Poster

Cancer.gov

By Andrea Frydl, Contributing Writer Although it was delayed by almost a month because of the federal shutdown, the NIH Research Festival still took place at the NIH Clinical Center in Bethesda, Md., and attendance was high.

Purely wavelength- and amplitude-modulated quartz-enhanced photoacoustic spectroscopy.

PubMed

Patimisco, Pietro; Sampaolo, Angelo; Bidaux, Yves; Bismuto, Alfredo; Scott, Marshall; Jiang, James; Muller, Antoine; Faist, Jerome; Tittel, Frank K; Spagnolo, Vincenzo

2016-11-14

We report here on a quartz-enhanced photoacoustic (QEPAS) sensor employing a quantum cascade laser (QCL) structure capable of operating in a pure amplitude or wavelength modulation configuration. The QCL structure is composed of three electrically independent sections: Gain, Phase (PS) and Master Oscillator (MO). Selective current pumping of these three sections allows obtaining laser wavelength tuning without changes in the optical power, and power modulation without emission wavelength shifts. A pure QEPAS amplitude modulation condition is obtained by modulating the PS current, while pure wavelength modulation is achieved by modulating simultaneously the MO and PS QCL sections and slowly scanning the DC current level injected in the PS section.

Effect of the Online Game Shutdown Policy on Internet Use, Internet Addiction, and Sleeping Hours in Korean Adolescents.

PubMed

Choi, Jiyun; Cho, Hyunseok; Lee, Seungmin; Kim, Juyeong; Park, Eun-Cheol

2018-05-01

Internet addiction has emerged as a major public health problem worldwide. In November 2011, the South Korean government implemented an online game shutdown policy, lasting from 12:00 to 6:00 am, as a means of preventing Internet addiction in adolescents aged 15 or below. This study analyzed the effect of this shutdown policy on adolescent Internet use, addiction, and sleeping hours. We analyzed data collected from the Korea Youth Risk Behavior Web-based Survey from 2011 to 2015. Respondents were divided into two groups by age: aged 15 or below (male = 76,048, female = 66,281) and aged 16 or above (male = 52,568, female = 49,060). A difference-in-difference analysis was used to evaluate the effect of this shutdown policy. In 2012, which is immediately following policy enforcement, daily amount of Internet use (in minutes) decreased more in adolescents affected by the policy (i.e., the aged 15 or below group). However, it steadily increased in 2013, 2014, 2015, and showed no meaningful long-term improvements 4 years after policy implementation (-3.648 minutes in 2012 [p = .001], -3.204 minutes in 2013 [p = .011], -1.140 minutes in 2014 [p = .384], and 2.190 minutes in 2015 [p = .107]). The shutdown policy did not alter Internet addiction or sleeping hours. Interestingly, female adolescents, adolescents with low academic performance, and adolescents with low exercise levels exhibited comparatively stronger and longer lasting initial declines in Internet usage. The shutdown policy had practically insignificant effects in reducing Internet use for target adolescents. Thus, policymakers aiming to reduce or prevent Internet addiction should use different strategies. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

46 CFR 63.15-7 - Alarms.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS General Requirements § 63.15-7 Alarms. (a) An audible alarm must automatically sound when a flame safety system shutdown occurs. A visible indicator must indicate that the shutdown was caused by the flame safety system...

46 CFR 63.15-7 - Alarms.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS General Requirements § 63.15-7 Alarms. (a) An audible alarm must automatically sound when a flame safety system shutdown occurs. A visible indicator must indicate that the shutdown was caused by the flame safety system...

46 CFR 63.15-7 - Alarms.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS General Requirements § 63.15-7 Alarms. (a) An audible alarm must automatically sound when a flame safety system shutdown occurs. A visible indicator must indicate that the shutdown was caused by the flame safety system...

46 CFR 63.15-7 - Alarms.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS General Requirements § 63.15-7 Alarms. (a) An audible alarm must automatically sound when a flame safety system shutdown occurs. A visible indicator must indicate that the shutdown was caused by the flame safety system...

46 CFR 63.15-7 - Alarms.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS General Requirements § 63.15-7 Alarms. (a) An audible alarm must automatically sound when a flame safety system shutdown occurs. A visible indicator must indicate that the shutdown was caused by the flame safety system...

30 CFR 7.103 - Safety system control test.

Code of Federal Regulations, 2014 CFR

2014-07-01

... sensors which will automatically activate the safety shutdown system and stop the engine before the... the temperature sensor in the exhaust gas stream which will automatically activate the safety shutdown... using a wet exhaust conditioner, determine the effectiveness of the temperature sensor in the exhaust...

30 CFR 7.103 - Safety system control test.

Code of Federal Regulations, 2013 CFR

2013-07-01

... sensors which will automatically activate the safety shutdown system and stop the engine before the... the temperature sensor in the exhaust gas stream which will automatically activate the safety shutdown... using a wet exhaust conditioner, determine the effectiveness of the temperature sensor in the exhaust...

30 CFR 7.103 - Safety system control test.

Code of Federal Regulations, 2012 CFR

2012-07-01

... sensors which will automatically activate the safety shutdown system and stop the engine before the... the temperature sensor in the exhaust gas stream which will automatically activate the safety shutdown... using a wet exhaust conditioner, determine the effectiveness of the temperature sensor in the exhaust...

40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... plan, the owner or operator may use the standard operating procedures manual for the battery, provided... startup, shutdown, and malfunction plan that describes procedures for operating the battery, including... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE...

40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... plan, the owner or operator may use the standard operating procedures manual for the battery, provided... startup, shutdown, and malfunction plan that describes procedures for operating the battery, including... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE...

40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... plan, the owner or operator may use the standard operating procedures manual for the battery, provided... startup, shutdown, and malfunction plan that describes procedures for operating the battery, including... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE...

40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... plan, the owner or operator may use the standard operating procedures manual for the battery, provided... startup, shutdown, and malfunction plan that describes procedures for operating the battery, including... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE...

Fermilab | Science

Science.gov Websites

Book Newsroom Newsroom News and features Press releases Photo gallery Fact sheets and brochures Media Tevatron experiments Tevatron operation Shutdown process For the media Video of shutdown event Guest book Quick Links Home Contact Phone Book Fermilab at Work For Industry Jobs Interact Facebook Twitter

40 CFR 63.2250 - What are the general requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., except during periods of process unit or control device startup, shutdown, and malfunction; prior to process unit initial startup; and during the routine control device maintenance exemption specified in... practice requirements are not operating, or during periods of startup, shutdown, and malfunction. Startup...

40 CFR 63.2250 - What are the general requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., except during periods of process unit or control device startup, shutdown, and malfunction; prior to process unit initial startup; and during the routine control device maintenance exemption specified in... practice requirements are not operating, or during periods of startup, shutdown, and malfunction. Startup...

40 CFR 63.2250 - What are the general requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., except during periods of process unit or control device startup, shutdown, and malfunction; prior to process unit initial startup; and during the routine control device maintenance exemption specified in... practice requirements are not operating, or during periods of startup, shutdown, and malfunction. Startup...

40 CFR 63.1354 - Reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... owner or operator during a startup, shutdown, or malfunction of an affected source (including actions taken to correct a malfunction) are consistent with the procedures specified in the source's startup... information in a semiannual report. Reports shall only be required if a startup, shutdown, or malfunction...

40 CFR 60.51Da - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... excluded from the calculation of average emission rates because of startup, shutdown, malfunction (NOX only... than startup, shutdown, malfunction, or emergency conditions. (6) Identification of “F” factor used for calculations, method of determination, and type of fuel combusted. (7) Identification of times when hourly...

49 CFR 192.167 - Compressor stations: Emergency shutdown.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Components § 192.167 Compressor stations: Emergency shutdown. (a) Except for unattended field compressor... fires, and electrical facilities in the vicinity of gas headers and in the compressor building, except that: (i) Electrical circuits that supply emergency lighting required to assist station personnel in...

49 CFR 192.167 - Compressor stations: Emergency shutdown.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Components § 192.167 Compressor stations: Emergency shutdown. (a) Except for unattended field compressor... fires, and electrical facilities in the vicinity of gas headers and in the compressor building, except that: (i) Electrical circuits that supply emergency lighting required to assist station personnel in...

The cochaperone shutdown defines a group of biogenesis factors essential for all piRNA populations in Drosophila.

PubMed

Olivieri, Daniel; Senti, Kirsten-André; Subramanian, Sailakshmi; Sachidanandam, Ravi; Brennecke, Julius

2012-09-28

In animal gonads, PIWI proteins and their bound 23-30 nt piRNAs guard genome integrity by the sequence specific silencing of transposons. Two branches of piRNA biogenesis, namely primary processing and ping-pong amplification, have been proposed. Despite an overall conceptual understanding of piRNA biogenesis, identity and/or function of the involved players are largely unknown. Here, we demonstrate an essential role for the female sterility gene shutdown in piRNA biology. Shutdown, an evolutionarily conserved cochaperone collaborates with Hsp90 during piRNA biogenesis, potentially at the loading step of RNAs into PIWI proteins. We demonstrate that Shutdown is essential for both primary and secondary piRNA populations in Drosophila. An extension of our study to previously described piRNA pathway members revealed three distinct groups of biogenesis factors. Together with data on how PIWI proteins are wired into primary and secondary processing, we propose a unified model for piRNA biogenesis. Copyright © 2012 Elsevier Inc. All rights reserved.

Antarctic Projects Stymied by the Shutdown

NASA Astrophysics Data System (ADS)

Showstack, Randy

2013-10-01

The U.S. federal government shutdown coincided with the beginning of the Antarctic austral summer research window, and many scientists told Eos they are deeply concerned about the impacts on research there. John Priscu, a lead principal investigator with the Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project in West Antarctica, said the government shutdown "threw us a curve that I did not anticipate or plan for." Pricsu, who has spent 30 seasons working in Antarctica under federal funding, said that a hole in the project's long-term data set "will have a major impact on the models we are developing to examine climate-induced changes" in Antarctic ecosystems.

Safety shutdown separators

DOEpatents

Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

2015-06-30

The present invention pertains to electrochemical cells which comprise (a) an anode; (b) a cathode; (c) a solid porous separator, such as a polyolefin, xerogel, or inorganic oxide separator; and (d) a nonaqueous electrolyte, wherein the separator comprises a porous membrane having a microporous coating comprising polymer particles which have not coalesced to form a continuous film. This microporous coating on the separator acts as a safety shutdown layer that rapidly increases the internal resistivity and shuts the cell down upon heating to an elevated temperature, such as 110.degree. C. Also provided are methods for increasing the safety of an electrochemical cell by utilizing such separators with a safety shutdown layer.

10 CFR 50.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... to bring and maintain the plant in safe shutdown (non-design basis accident). Applicant means a... Document Control Desk. Nuclear reactor means an apparatus, other than an atomic weapon, designed or used to... from the Restricted Data category pursuant to section 142 of the Act. Safe shutdown (non-design basis...

10 CFR 50.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... to bring and maintain the plant in safe shutdown (non-design basis accident). Applicant means a... Document Control Desk. Nuclear reactor means an apparatus, other than an atomic weapon, designed or used to... from the Restricted Data category pursuant to section 142 of the Act. Safe shutdown (non-design basis...

10 CFR 50.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... to bring and maintain the plant in safe shutdown (non-design basis accident). Applicant means a... Document Control Desk. Nuclear reactor means an apparatus, other than an atomic weapon, designed or used to... from the Restricted Data category pursuant to section 142 of the Act. Safe shutdown (non-design basis...

10 CFR 50.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... to bring and maintain the plant in safe shutdown (non-design basis accident). Applicant means a... Document Control Desk. Nuclear reactor means an apparatus, other than an atomic weapon, designed or used to... from the Restricted Data category pursuant to section 142 of the Act. Safe shutdown (non-design basis...

47 CFR 95.628 - MedRadio transmitters in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz bands.

Code of Federal Regulations, 2012 CFR

2012-10-01

... transmitters shall incorporate a programmable means to implement a system shutdown process in the event of... transmitters shall incorporate a programmable means to implement a system shutdown process in the event of...

40 CFR 63.1101 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... operation. A unit operation may have more than one batch emission episode per batch cycle. For example, a... shutdowns and during periods not associated with a shutdown. Examples of activities that can generate... management units such as an air flotation unit, clarifier, or biological treatment unit. Examples of an oil...

40 CFR 63.1101 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... operation. A unit operation may have more than one batch emission episode per batch cycle. For example, a... shutdowns and during periods not associated with a shutdown. Examples of activities that can generate... management units such as an air flotation unit, clarifier, or biological treatment unit. Examples of an oil...

40 CFR 63.1101 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... operation. A unit operation may have more than one batch emission episode per batch cycle. For example, a... shutdowns and during periods not associated with a shutdown. Examples of activities that can generate... management units such as an air flotation unit, clarifier, or biological treatment unit. Examples of an oil...

40 CFR 63.1101 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... operation. A unit operation may have more than one batch emission episode per batch cycle. For example, a... shutdowns and during periods not associated with a shutdown. Examples of activities that can generate... management units such as an air flotation unit, clarifier, or biological treatment unit. Examples of an oil...

40 CFR 63.1101 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... operation. A unit operation may have more than one batch emission episode per batch cycle. For example, a... shutdowns and during periods not associated with a shutdown. Examples of activities that can generate... management units such as an air flotation unit, clarifier, or biological treatment unit. Examples of an oil...

Fermilab | Contact Fermilab

Science.gov Websites

Book Newsroom Newsroom News and features Press releases Photo gallery Fact sheets and brochures Media Tevatron experiments Tevatron operation Shutdown process For the media Video of shutdown event Guest book Cookies Quick Links Home Contact Phone Book Fermilab at Work For Industry Jobs Interact Facebook Twitter

Fermilab | About Fermilab

Science.gov Websites

Book Newsroom Newsroom News and features Press releases Photo gallery Fact sheets and brochures Media Tevatron experiments Tevatron operation Shutdown process For the media Video of shutdown event Guest book Links Home Contact Phone Book Fermilab at Work For Industry Jobs Interact Facebook Twitter Instagram

Testing of Liquid Metal Components for Nuclear Surface Power Systems

NASA Technical Reports Server (NTRS)

Polzin, Kurt A.; Godfroy, Thomas J.; Pearson, J. Boise

2010-01-01

The Early Flight Fission Test Facility (EFF-TF) was established by the Marshall Space Flight Center (MSFC) to provide a capability for performing hardware-directed activities to support multiple in-space nuclear reactor concepts by using a non-nuclear test methodology. This includes fabrication and testing at both the module/component level and near prototypic reactor configurations. The EFF-TF is currently supporting an effort to develop an affordable fission surface power (AFSP) system that could be deployed on the Lunar surface. The AFSP system is presently based on a pumped liquid metal-cooled (Sodium-Potassium eutectic, NaK-78) reactor design. This design was derived from the only fission system that the United States has deployed for space operation, the Systems for Nuclear Auxiliary Power (SNAP) 10A reactor, which was launched in 1965. Two prototypical components recently tested at MSFC were a pair of Stirling power conversion units that would be used in a reactor system to convert heat to electricity, and an annular linear induction pump (ALIP) that uses travelling electromagnetic fields to pump the liquid metal coolant through the reactor loop. First ever tests were conducted at MSFC to determine baseline performance of a pair of 1 kW Stirling convertors using NaK as the hot side working fluid. A special test rig was designed and constructed and testing was conducted inside a vacuum chamber at MSFC. This test rig delivered pumped NaK for the hot end temperature to the Stirlings and water as the working fluid on the cold end temperature. These test were conducted through a hot end temperature range between 400 to 550C in increments of 50 C and a cold end temperature range from 30 to 70 C in 20 C increments. Piston amplitudes were varied from 6 to 1 1mm in .5 mm increments. A maximum of 2240 Watts electric was produced at the design point of 550 hot end, 40 C cold end with a piston amplitude of 10.5mm. This power level was reached at a gross thermal efficiency of 28%. A baseline performance map was established for the pair of 1kW Stirling convertors. The performance data will then be used for design modification to the Stirling convertors. The ALIP tested at MSFC has no moving parts and no direct electrical connections to the liquid metal containing components. Pressure is developed by the interaction of the magnetic field produced by the stator and the current which flows as a result of the voltage induced in the liquid metal contained in the pump duct. Flow is controlled by variation of the voltage supplied to the pump windings. Under steady-state conditions, pump performance is measured for flow rates from 0.5-4.3 kg/s. The pressure rise developed by the pump to support these flow rates is roughly 5-65 kPa. The RMS input voltage (phase-to-phase voltage) ranges from 5-120 V, while the frequency can be varied arbitrarily up to 60 Hz. Performance is quantified at different loop temperature levels from 50 C up to 650 C, which is the peak operating temperature of the proposed AFSP reactor. The transient response of the pump is also evaluated to determine its behavior during startup and shut-down procedures.

High power, high signal-to-noise ratio single-frequency 1μm Brillouin all-fiber laser

NASA Astrophysics Data System (ADS)

Wang, Jing; Hou, Yubin; Zhang, Qian; Jin, Dongchen; Sun, Ruoyu; Shi, Hongxing; Liu, Jiang; Wang, Pu

2016-03-01

We demonstrate a high-power, high signal-to-noise ratio single-frequency 1 μm Brillouin all-fiber laser with high slope efficiency. The Brillouin laser system consists of a high-power single-frequency fiber laser and a single-pass Brillouin ring cavity. The high-power single-frequency fiber laser is one-stage master-oscillator power amplifier with the maximum output power of 10.33 W, the signal-to-noise ratio of 50 dB and the slope efficiency of 46%. The Brillouin fiber laser is pumped by the amplified laser with a linewidth of 33 kHz and an output power of 2.61 W limited by the damage threshold of the optical isolator. By optimizing the length of the Brillouin ring cavity to 10 m, stable singlefrequency Brillouin fiber laser is obtained with 3 kHz linewidth owing to the linewidth narrowing effect. At the launched pump power of 2.15 W, the Brillouin fiber laser generates maximum output power of 1.4 W with a slope efficiency of 79% and the optical signal-to-noise ratio of 77 dB.

Learning from jellyfish: Fluid transport in muscular pumps at intermediate Reynolds numbers

NASA Astrophysics Data System (ADS)

Nawroth, Janna; Dabiri, John

2010-11-01

Biologically inspired hydrodynamic propulsion and maneuvering strategies promise the advancement of medical implants and minimally invasive clinical tools. We have chosen juvenile jellyfish as a model system for investigating fluid dynamics and morphological properties underlying fluid transport by a muscular pump at intermediate Reynolds numbers. Recently we have described how natural variations in viscous forces are balanced by changes in jellyfish body shape (phenotypic plasticity), to the effect of facilitating efficient body-fluid interaction. Complementing these studies in our live model organisms, we are also engaged in engineering an artificial jellyfish, that is, a jellyfish-inspired construct of a flexible plastic sheet actuated by a monolayer of rat cardiomyocytes. The main challenges here are (1) to derive a body shape and deformation suitable for effective fluid transport under physiological conditions, (2) to understand the mechanical properties of the muscular film and derive a design capable of the desired deformation, (3) to master the proper alignment and timely contraction of the muscle component needed to achieve the desired deformation, and (4) to evaluate the performance of the design.

Practical application of cross correlation technique to measure jitter of master-oscillator-power-amplifier laser system

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

Młyńczak, J.; Sawicz-Kryniger, K.; Fry, A. R.

2014-01-01

The Linac coherent light source (LCLS) at the SLAC National Accelerator Laboratory (SLAC) is the world’s first hard X-ray free electron laser (XFEL) and is capable of producing high-energy, femtosecond duration X-ray pulses. A common technique to study fast timescale physical phenomena, various “pump/probe” techniques are used. In these techniques there are two lasers, one optical and one X-ray, that work as a pump and as a probe to study dynamic processes in atoms and molecules. In order to resolve phenomena that occur on femtosecond timescales, it is imperative to have very precise timing between the optical lasers and X-raysmore » (on the order of ~ 20 fs or better). The lasers are synchronized to the same RF source that drives the accelerator and produces the X-ray laser. However, elements in the lasers cause some drift and time jitter, thereby de-synchronizing the system. This paper considers cross-correlation technique as a way to quantify the drift and jitter caused by the regenerative amplifier of the ultrafast optical laser.« less

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40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... CATEGORIES National Emission Standards for Coke Oven Batteries § 63.310 Requirements for startups, shutdowns... or operator shall operate and maintain the coke oven battery and its pollution control equipment... operator of a coke oven battery shall develop, according to paragraph (c) of this section, a written...

46 CFR 153.296 - Emergency shutdown stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... shutdown station must contain a single remote actuator for all quick closing shutoff valves required by... on the tankship. (f) Any remote emergency actuator, such as that for a quick closing shut-off valve... remote emergency actuators. The emergency action must occur whether one or several actuators are operated...

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40 CFR 63.1590 - What reports must I submit?

Code of Federal Regulations, 2010 CFR

2010-07-01

... continuing compliance; (iv) The type and quantity of HAP emitted by your POTW treatment plant; (v) A... notification of performance tests; a performance test report; a startup, shutdown, and malfunction report; and... prior to beginning operation of your new or reconstructed POTW. You must also submit a startup, shutdown...

40 CFR 60.11 - Compliance with standards and maintenance requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (meaning those fugitive-type emission sources subject only to an opacity standard). (c) The opacity standards set forth in this part shall apply at all times except during periods of startup, shutdown... startup, shutdown, and malfunction, owners and operators shall, to the extent practicable, maintain and...

40 CFR 63.7555 - What records must I keep?

Code of Federal Regulations, 2010 CFR

2010-07-01

... (v) related to startup, shutdown, and malfunction. (3) Records of performance tests, fuel analyses... the deviation occurred during a period of startup, shutdown, or malfunction or during another period... monthly fuel use by each boiler or process heater, including the type(s) of fuel and amount(s) used. (2...

40 CFR 63.7555 - What records must I keep?

Code of Federal Regulations, 2012 CFR

2012-07-01

... (v) related to startup, shutdown, and malfunction. (3) Records of performance tests, fuel analyses... the deviation occurred during a period of startup, shutdown, or malfunction or during another period... monthly fuel use by each boiler or process heater, including the type(s) of fuel and amount(s) used. (2...

40 CFR 63.9050 - What reports must I submit and when?

Code of Federal Regulations, 2012 CFR

2012-07-01

... of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance... period. This description shall include the type of maintenance performed and the total number of hours...

40 CFR 63.7555 - What records must I keep?

Code of Federal Regulations, 2011 CFR

2011-07-01

... (v) related to startup, shutdown, and malfunction. (3) Records of performance tests, fuel analyses... the deviation occurred during a period of startup, shutdown, or malfunction or during another period... monthly fuel use by each boiler or process heater, including the type(s) of fuel and amount(s) used. (2...

40 CFR 63.1590 - What reports must I submit?

Code of Federal Regulations, 2011 CFR

2011-07-01

... continuing compliance; (iv) The type and quantity of HAP emitted by your POTW treatment plant; (v) A... notification of performance tests; a performance test report; a startup, shutdown, and malfunction report; and... prior to beginning operation of your new or reconstructed POTW. You must also submit a startup, shutdown...

40 CFR 63.9050 - What reports must I submit and when?

Code of Federal Regulations, 2011 CFR

2011-07-01

... of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance... period. This description shall include the type of maintenance performed and the total number of hours...

40 CFR 63.9050 - What reports must I submit and when?

Code of Federal Regulations, 2013 CFR

2013-07-01

... of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance... period. This description shall include the type of maintenance performed and the total number of hours...

40 CFR 63.9050 - What reports must I submit and when?

Code of Federal Regulations, 2014 CFR

2014-07-01

... of the reporting period. (4) If you had a startup, shutdown, or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance... period. This description shall include the type of maintenance performed and the total number of hours...

40 CFR 63.1346 - Operating limits for kilns.

Code of Federal Regulations, 2011 CFR

2011-07-01

... not exceeded, except during periods of startup/shutdown when the temperature limit may be exceeded by..., except during periods of startup/shutdown when the temperature limit may be exceeded by no more than 10... performance test, with or without the raw mill operating, is not exceeded, except during periods of startup...

40 CFR 63.1346 - Operating limits for kilns.

Code of Federal Regulations, 2012 CFR

2012-07-01

... not exceeded, except during periods of startup/shutdown when the temperature limit may be exceeded by..., except during periods of startup/shutdown when the temperature limit may be exceeded by no more than 10... performance test, with or without the raw mill operating, is not exceeded, except during periods of startup...

40 CFR 63.102 - General standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in § 63.101 of this subpart), malfunction, or non-operation of the chemical manufacturing process... subpart G of this part apply. However, if a start-up, shutdown, malfunction or period of non-operation of... part during the start-up, shutdown, malfunction or period of non-operation. For example, if there is an...

Every Good Virtue You Ever Wanted in a Q-switched Solid-state Laser and More: Monolithic, Diode-pumped, Self-q-switched, Highly Reproducible, Diffraction-limited Nd:yag Laser

NASA Technical Reports Server (NTRS)

Chen, Y. C.; Lee, K. K.

1993-01-01

The applications of Q-switched lasers are well known, for example, laser radar, laser remote sensing, satellite orbit determination, Moon orbit and 'moon quake' determination, satellite laser communication, and many nonlinear optics applications. Most of the applications require additional properties of the Q-switched lasers, such as single-axial and/or single-transverse mode, high repetition rate, stable pulse shape and pulse width, or ultra compact and rugged oscillators. Furthermore, space based and airborne lasers for lidar and laser communication applications require efficient, compact, lightweight, long-lived, and stable-pulsed laser sources. Diode-pumped solid-state lasers (DPSSL) have recently shown the potential for satisfying all of these requirements. We will report on the operating characteristics of a diode-pumped, monolithic, self-Q-switched Cr,Nd:YAG laser where the chromium ions act as a saturable absorber for the laser emission at 1064 nm. The pulse duration is 3.5 ns and the output is highly polarized with an extinction ratio of 700:1. It is further shown that the output is single-longitudinal-mode with transform-limited spectral line width without pulse-to-pulse mode competition. Consequently, the pulse-to-pulse intensity fluctuation is less than the instrument resolution of 0.25 percent. This self-stabilization mechanism is because the lasing mode bleaches the distributed absorber and establishes a gain-loss grating similar to that used in the distributed feedback semiconductor lasers. A repetition rate above 5 KHz has also been demonstrated. For higher power, this laser can be used for injection seeding an amplifier (or amplifier chain) or injection locking of a power oscillator pumped by diode lasers. We will discuss some research directions on the master oscillator for higher output energy per pulse as well as how to scale the output power of the diode-pumped amplifier(s) to multi-kilowatt average power.

In Vivo Evaluation of Active and Passive Physiological Control Systems for Rotary Left and Right Ventricular Assist Devices.

PubMed

Gregory, Shaun D; Stevens, Michael C; Pauls, Jo P; Schummy, Emma; Diab, Sara; Thomson, Bruce; Anderson, Ben; Tansley, Geoff; Salamonsen, Robert; Fraser, John F; Timms, Daniel

2016-09-01

Preventing ventricular suction and venous congestion through balancing flow rates and circulatory volumes with dual rotary ventricular assist devices (VADs) configured for biventricular support is clinically challenging due to their low preload and high afterload sensitivities relative to the natural heart. This study presents the in vivo evaluation of several physiological control systems, which aim to prevent ventricular suction and venous congestion. The control systems included a sensor-based, master/slave (MS) controller that altered left and right VAD speed based on pressure and flow; a sensor-less compliant inflow cannula (IC), which altered inlet resistance and, therefore, pump flow based on preload; a sensor-less compliant outflow cannula (OC) on the right VAD, which altered outlet resistance and thus pump flow based on afterload; and a combined controller, which incorporated the MS controller, compliant IC, and compliant OC. Each control system was evaluated in vivo under step increases in systemic (SVR ∼1400-2400 dyne/s/cm(5) ) and pulmonary (PVR ∼200-1000 dyne/s/cm(5) ) vascular resistances in four sheep supported by dual rotary VADs in a biventricular assist configuration. Constant speed support was also evaluated for comparison and resulted in suction events during all resistance increases and pulmonary congestion during SVR increases. The MS controller reduced suction events and prevented congestion through an initial sharp reduction in pump flow followed by a gradual return to baseline (5.0 L/min). The compliant IC prevented suction events; however, reduced pump flows and pulmonary congestion were noted during the SVR increase. The compliant OC maintained pump flow close to baseline (5.0 L/min) and prevented suction and congestion during PVR increases. The combined controller responded similarly to the MS controller to prevent suction and congestion events in all cases while providing a backup system in the event of single controller failure. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Recent developments in high altitude aircraft sampling - Mount St. Helens and stratospheric trace gases

NASA Astrophysics Data System (ADS)

Leifer, R.; Sommers, K. G.; Guggenheim, S. F.; Fisenne, I.

1981-02-01

An ultra-clean, low volume gas sampling system (CLASS), flown aboard a high altitude aircraft (WB-57F), and providing information on stratospheric trace gases is presented. Attention is given to the instrument design and the electronic control design. Since remote operation is mandatory on the WB-57F, a servo pressure transducer, electrical pressure switch for automatic shutdown, and a mechanical safety relief valve were installed on the sampling manifold, indicated on the CLASS flow chart. The electronic control system consists of hermetically sealed solid state timers, relays, and a stepping switch, for controlling the compressor pump and solenoid valves. In designing the automatic control system, vibration, shock, acceleration, extreme low temperature, and aircraft safety were important considerations. CLASS was tested on three separate occasions, and tables of analytical data from these flights are presented. Readiness capability was demonstrated when the Mount St. Helens eruption plume of May 18, 1980, was intercepted, and it was concluded that no large injection of Rn-222 entered the stratosphere or troposphere from the eruption.

Core cooling under accident conditions at the high-flux beam reactor

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

Tichler, P.; Cheng, L.; Fauske, H.

The High-Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL) is cooled and moderated by heavy water and contains {sup 235}U in the form of narrow-channel, parallel-plate-type fuel elements. During normal operation, the flow direction is downward through the core. This flow direction is maintained at a reduced flow rate during routine shutdown and on loss of commercial power by means of redundant pumps and power supplies. However, in certain accident scenarios, e.g. loss-of-coolant accidents (LOCAs), all forced-flow cooling is lost. Although there was experimental evidence during the reactor design period (1958-1963) that the heat removal capacity in the fullymore » developed natural circulation cooling mode was relatively high, it was not possible to make a confident prediction of the heat removal capacity during the transition from downflow to natural circulation. Accordingly, a test program was initiated using an electrically heated section to simulate the fuel channel and a cooling loop to simulate the balance of the primary cooling system.« less

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

Wegemar, B.

Operating experiences from the Forsmark 3 and Oskarshamn 3 BWRs have been evaluated during the first two cycles of their operation. The objective of this work was to determine the influence on water chemistry quality and radiation field buildup from the special design characteristics of these plants. Important differences from older ASEA-ATOM BWRs include the concept of forward pumped high pressure heater drains, magnetic filtration of high pressure drains and use of more erosion-resistant materials in turbine components. Data obtained from water radiochemistry measurements, shutdown dose rates and gamma scanning surveys, fuel deposit analyses and occuptional exposure statistics have beenmore » used in order to enable a comparsion to older ASEA-ATOM BWRs. At the end of the second cycles, satisfactory feedwater quality was reported in both plants. Radiation levels around components in the primary systems are higher in Forsmark 3 and Oskarshamn 3 as compared to other plants. This is in agreement with reactor water activities, fuel deposits and gamma scanning surveys, indicating somewhat higher amounts of cobalt-60 and cobalt-58. However, in both plants occupational exposures were low during the first two years of operation.« less

Combustion stability analysis of preburners in liquid propellant rocket engines during shutdown

NASA Technical Reports Server (NTRS)

Lim, Kair-Chuan; George, Paul E., II

1987-01-01

A linearized one-dimensional lumped-parameter model capable of predicting the occurrence of the low frequency combustion instability (chugging) experienced during preburner shutdown in the Space Shuttle Main Engines is discussed, and predictions are compared with NASA experimental results. Results from a parametric study of parameters including chamber pressure, fuel and oxygen temperatures, and the effective bulk modulus of the liquid oxidizer suggest that chugging is probably affected by conditions at shutdown through the fuel and oxidizer temperatures. It is suggested that chugging is initiated when the fuel, oxidizer, and helium temperature and flow rates pass into an unstable region, and that chugging may be terminated by decaying pressures.

Lasing in strongly scattering dielectric microstructures

NASA Astrophysics Data System (ADS)

Florescu, Lucia

In the first part of this thesis, a detailed analysis of lasing in random multiple-light-scattering media with gain is presented. Random laser emission is analyzed using a time-dependent diffusion model for light propagating in the medium containing active atoms. We demonstrate the effects of scatterers to narrow the emission spectral linewidth and to shorten the emitted pulse duration at a specific threshold pump intensity. This threshold pump intensity decreases with scatterer density and excitation spot diameter, in excellent agreement with experimental results. The coherence properties of the random laser are studied using a generalized master equation. The random laser medium is treated as a collection of low quality-factor cavities, coupled by random photon diffusion. Laser-like coherence, on average, is demonstrated above a specific pumping threshold. We demonstrate that with stronger scattering, the pumping threshold for the transition from chaotic to isotropic coherent light emission decreases and enhanced optical coherence for the emitted light is achieved above threshold. The second part of this thesis presents a study of lasing in photonic crystals (PCs). The emission from an incoherently pumped atomic system in interaction with the electro-magnetic reservoir of a PC is analyzed using a set of generalized semiclassical Maxwell-Bloch equations. We demonstrate that the photonic band edge facilitates the enhancement of stimulated emission and the reduction of internal losses, leading to an important lowering of the laser threshold. In addition, an increase of the laser output at a photonic band edge is demonstrated. We next develop a detailed quantum theory of a coherently pumped two-level atom in a photonic band gap material, coupled to both a multi-mode wave-guide channel and a high-quality micro-cavity embedded within the PC. The cavity field characteristics are highly distinct from that of a corresponding high-Q cavity in ordinary vacuum. We demonstrate enhanced, inversionless, and nearly coherent light generation when the photon density of states (DOS) jump between the Mollow spectral components of atomic resonance fluorescence is large. In the case of a vanishing photon DOS on the lower Mollow sideband and no dipolar dephasing, the emitted photon statistics is Poissonian and the cavity field exhibits quadrature coherence.

40 CFR 74.46 - Opt-in source permanent shutdown, reconstruction, or change in affected status.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Opt-in source permanent shutdown, reconstruction, or change in affected status. 74.46 Section 74.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Allowance Tracking and Transfer...

25 CFR 226.28 - Shutdown, abandonment, and plugging of wells.

Code of Federal Regulations, 2010 CFR

2010-04-01

... OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Cessation of Operations § 226.28 Shutdown, abandonment... production of oil and/or gas has been demonstrated to the satisfaction of the Superintendent. Lessee shall... the means by which the well bore is to be protected, and the contemplated eventual disposition of the...

A 100 kW experimental wind turbine: Simulation of starting, overspeed, and shutdown characteristics

NASA Technical Reports Server (NTRS)

Gilbert, L. J.

1976-01-01

The ERDA/NASA 100 kW experimental wind turbine is modeled on a digital computer in order to study the performance of a wind turbine under operating conditions. Simulation studies of starting, overspeed, and shutdown performance were made. From these studies operating procedures, precautions, and limitations are prescribed.

46 CFR 153.408 - Tank overflow control.

Code of Federal Regulations, 2010 CFR

2010-10-01

... automatic shutdown system must: (1) Be independent of one-another; and (2) Operate on loss of power. (c) The... lettering as specified for the warning sign in § 153.955. (e) A tank overflow alarm must be audible and... loading is controlled on the tankship. (f) The automatic shutdown system or tank overflow alarm must be...

46 CFR 153.408 - Tank overflow control.

Code of Federal Regulations, 2011 CFR

2011-10-01

... automatic shutdown system must: (1) Be independent of one-another; and (2) Operate on loss of power. (c) The... lettering as specified for the warning sign in § 153.955. (e) A tank overflow alarm must be audible and... loading is controlled on the tankship. (f) The automatic shutdown system or tank overflow alarm must be...

78 FR 49553 - Three Mile Island, Unit 2; Post Shutdown Decommissioning Activities Report

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-14

...On June 28, 2013, the GPU Nuclear Inc. (GPUN) submitted its Post Shutdown Decommissioning Activity Report (PSDAR) for Three Mile Island, Unit 2 (TMI-2). The PSDAR provides an overview of GPUN's proposed decommissioning activities, schedule, and costs for TMI-2. The NRC is requesting public comments on the PSDAR.

Application of a Self-Actuating Shutdown System (SASS) to a Gas-Cooled Fast Reactor (GCFR)

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

Germer, J.H.; Peterson, L.F.; Kluck, A.L.

1980-09-01

The application of a SASS (Self-Actuated Shutdown System) to a GCFR (Gas-Cooled Fast Reactor) is compared with similar systems designed for an LMFBR (Liquid Metal Fast Breeder Reactor). A comparison of three basic SASS concepts is given: hydrostatic holdup, fluidic control, and magnetic holdup.

78 FR 19540 - Dominion Energy Kewaunee, Inc., Kewaunee Power Station Post-Shutdown Decommissioning Activities...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-01

... (KPS) Post-Shutdown Decommissioning Activities Report (PSDAR), Revision 0, on Wednesday, April 24, 2013... Management System (ADAMS) Accession No. ML13058A065. In a prior communication on November 2, 2012 (ADAMS... at KPS pending completion of a grid stability review by the Midwest Independent Transmission System...

Impact of Government Shutdown on Child Care and Early Education Programs

ERIC Educational Resources Information Center

Center for Law and Social Policy, Inc. (CLASP), 2013

2013-01-01

Congress did not enact a continuing resolution bill by midnight September 30, 2013, thereby triggering a partial government shutdown effective October 1, 2013. October 1 began the federal fiscal year 2014. Most discretionary programs, those that are subject to the annual Congressional appropriations process, will not receive 2014 funding. Most,…

76 FR 57900 - Airworthiness Directives; WYTWORNIA SPRZETU KOMUNIKACYJNEGO (WSK) “PZL-RZESZOW”-SPOLKA AKCYJNA...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-19

... Turboshaft Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule; request for... describes the unsafe condition as: An uncommanded engine in-flight shutdown of a PZL-10W has been recently reported. The investigation has shown that the uncommanded engine in-flight shutdown was due to excessive...

Fermilab | Science | Questions for the Universe | Einstein's Dream of

Science.gov Websites

Navbar Toggle Search Search Home About Science Jobs Contact Phone Book Newsroom Newsroom News and Tevatron experiments Tevatron operation Shutdown process For the media Video of shutdown event Guest book Home Contact Phone Book Fermilab at Work For Industry Jobs Interact Facebook Twitter Instagram Google

40 CFR 74.46 - Opt-in source permanent shutdown, reconstruction, or change in affected status.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Opt-in source permanent shutdown, reconstruction, or change in affected status. 74.46 Section 74.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE OPT-INS Allowance Tracking and Transfer...

40 CFR Table 15 to Subpart Xxxx of... - Requirements for Reports

Code of Federal Regulations, 2014 CFR

2014-07-01

... reporting in § 63.6010(f). c. If you had a startup, shutdown or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance report....6010(b), unless you meet the requirements for annual reporting in § 63.6010(f). 2. Immediate startup...

40 CFR 63.7720 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... operation and maintenance requirements in this subpart at all times, except during periods of startup... process and emissions control equipment. (c) You must develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). The startup, shutdown, and malfunction plan also must...

40 CFR 60.2120 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... 1, 2001 Emission Limitations and Operating Limits § 60.2120 What happens during periods of startup... during CISWI unit startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3...

40 CFR 63.7720 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... operation and maintenance requirements in this subpart at all times, except during periods of startup... process and emissions control equipment. (c) You must develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). The startup, shutdown, and malfunction plan also must...

40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What happens during periods of startup... Emission Limitations and Operating Limits § 60.2918 What happens during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups...

40 CFR 63.7720 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... operation and maintenance requirements in this subpart at all times, except during periods of startup... process and emissions control equipment. (c) You must develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). The startup, shutdown, and malfunction plan also must...

40 CFR Table 15 to Subpart Xxxx of... - Requirements for Reports

Code of Federal Regulations, 2012 CFR

2012-07-01

... reporting in § 63.6010(f). c. If you had a startup, shutdown or malfunction during the reporting period and you took actions consistent with your startup, shutdown, and malfunction plan, the compliance report....6010(b), unless you meet the requirements for annual reporting in § 63.6010(f). 2. Immediate startup...

40 CFR 63.7720 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... operation and maintenance requirements in this subpart at all times, except during periods of startup... process and emissions control equipment. (c) You must develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). The startup, shutdown, and malfunction plan also must...

40 CFR 60.2120 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What happens during periods of startup... 1, 2001 Emission Limitations and Operating Limits § 60.2120 What happens during periods of startup... during CISWI unit startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3...

40 CFR 60.2120 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What happens during periods of startup... 1, 2001 Emission Limitations and Operating Limits § 60.2120 What happens during periods of startup... during CISWI unit startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3...

40 CFR 63.7720 - What are my general requirements for complying with this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... operation and maintenance requirements in this subpart at all times, except during periods of startup... process and emissions control equipment. (c) You must develop a written startup, shutdown, and malfunction plan according to the provisions in § 63.6(e)(3). The startup, shutdown, and malfunction plan also must...

40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What happens during periods of startup... Emission Limitations and Operating Limits § 60.2918 What happens during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups...

40 CFR 63.1211 - What are the recordkeeping and reporting requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... compliance date granted under § 63.6(i). 63.10(d)(5)(i) Periodic startup, shutdown, and malfunction reports. 63.10(d)(5)(ii) Immediate startup, shutdown, and malfunction reports. 63.10(e)(3) Excessive emissions and continuous monitoring system performance report and summary report. 63.1206(c)(2)(ii)(B) Startup...