WorldWideScience

Sample records for pre-pump release rate

  1. Gas release during salt-well pumping: Model predictions and laboratory validation studies for soluble and insoluble gases

    International Nuclear Information System (INIS)

    Peurrung, L.M.; Caley, S.M.; Gauglitz, P.A.

    1997-08-01

    The Hanford Site has 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. Of these, 67 are known or suspected to have leaked liquid from the tanks into the surrounding soil. Salt-well pumping, or interim stabilization, is a well-established operation for removing drainable interstitial liquid from SSTs. The overall objective of this ongoing study is to develop a quantitative understanding of the release rates and cumulative releases of flammable gases from SSTs as a result of salt-well pumping. The current study is an extension of the previous work reported by Peurrung et al. (1996). The first objective of this current study was to conduct laboratory experiments to quantify the release of soluble and insoluble gases. The second was to determine experimentally the role of characteristic waste heterogeneities on the gas release rates. The third objective was to evaluate and validate the computer model STOMP (Subsurface Transport over Multiple Phases) used by Peurrung et al. (1996) to predict the release of both soluble (typically ammonia) and insoluble gases (typically hydrogen) during and after salt-well pumping. The fourth and final objective of the current study was to predict the gas release behavior for a range of typical tank conditions and actual tank geometry. In these models, the authors seek to include all the pertinent salt-well pumping operational parameters and a realistic range of physical properties of the SST wastes. For predicting actual tank behavior, two-dimensional (2-D) simulations were performed with a representative 2-D tank geometry

  2. Hydrogen pumping and release by graphite under high flux plasma bombardment

    International Nuclear Information System (INIS)

    Hirooka, Y.; Leung, W.K.; Conn, R.W.; Goebel, D.M.; LaBombard, B.; Nygren, R.; Wilson, K.L.

    1988-01-01

    Inert gas (helium or argon) plasma bombardment has been found to increase the surface gas adsorptivity of isotropic graphite (POCO-graphite), which can then getter residual gases in a high vacuum system. The inert gas plasma bombardment was carried out at a flux ≅ 1 x 10 18 ions s -1 cm -2 to a fluence of the order of 10 21 ions/cm 2 and at temperatures around 800 0 C. The gettering capability of graphite can be easily recovered by repeating inert gas plasma bombardment. The activated graphite surface exhibits a smooth, sponge-like morphology with significantly increased pore openings, which correlates with the observed increase in the surface gas adsorptivity. The activated graphite surface has been observed to pump hydrogen plasma particles as well. From calibrated H-alpha measurements, the dynamic hydrogen retention capacity is evaluated to be as large as 2 x 10 18 H/cm 2 at temperatures below 100 0 C and at a plasma bombarding energy of 300 eV. The graphite temperature was varied between 15 and 480 0 C. Due to the plasma particle pumping capability, hydrogen recycling from the activated graphite surface is significantly reduced, relative to that from a pre-saturated surface. A pre-saturated surface was also observed to reproducibly pump a hydrogen plasma to a concentration of 9.5 x 10 17 H/cm 2 . The hydrogen retention capacity of graphite is found to decrease with increasing temperature. A transient pumping mechanism associated with the sponge-like surface morphology is conjectured to explain the large hydrogen retention capacity. Hydrogen release behavior under helium and argon plasma bombardment was also investigated, and the result indicated the possibility of some in-pore retrapping effect. 43 refs., 11 figs

  3. Development and Evaluation of High Bioavailable Sustained-Release Nimodipine Tablets Prepared with Monolithic Osmotic Pump Technology.

    Science.gov (United States)

    Kong, Hua; Yu, Fanglin; Liu, Yan; Yang, Yang; Li, Mingyuan; Cheng, Xiaohui; Hu, Xiaoqin; Tang, Xuemei; Li, Zhiping; Mei, Xingguo

    2018-01-01

    Frequent administration caused by short half-life and low bioavailability due to poor solubility and low dissolution rate limit the further application of poorly water-soluble nimodipine, although several new indications have been developed. To overcome these shortcomings, sophisticated technologies had to be used since the dose of nimodipine was not too low and the addition of solubilizers could not resolve the problem of poor release. The purpose of this study was to obtain sustained and complete release of nimodipine with a simple and easily industrialized technology. The expandable monolithic osmotic pump tablets containing nimodipine combined with poloxamer 188 and carboxymethylcellulose sodium were prepared. The factors affecting drug release including the amount of solubilizing agent, expanding agent, retarding agent in core tablet and porogenic agent in semipermeable film were optimized. The release behavior was investigated both in vitro and in beagle dogs. It was proved that the anticipant release of nimodipine could be realized in vitro. The sustained and complete release of nimodipine was also realized in beagles because the mean residence time of nimodipine from the osmotic pump system was longer and Cmax was lower than those from the sustained-release tablets in market while there was no difference in AUC(0-t) of the monolithic osmotic pump tablets and the sustained release tablets in market. It was reasonable to believe that the sustained and complete release of poorly watersoluble nimodipine could be realized by using simple expandable monolithic osmotic pump technology combined with surfactant. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Controlling Release of Integral Lipid Nanoparticles Based on Osmotic Pump Technology.

    Science.gov (United States)

    Tian, Zhiqiang; Yu, Qin; Xie, Yunchang; Li, Fengqian; Lu, Yi; Dong, Xiaochun; Zhao, Weili; Qi, Jianping; Wu, Wei

    2016-08-01

    To achieve controlled release of integral nanoparticles by the osmotic pump strategy using nanostructured lipid carriers (NLCs) as model nanoparticles. NLCs was prepared by a hot-homogenization method, transformed into powder by lyophilization, and formulated into osmotic pump tablets (OPTs). Release of integral NLCs was visualized by live imaging after labeling with a water-quenching fluorescent probe. Effects of formulation variables on in vitro release characteristics were evaluated by measuring the model drug fenofibrate. Pharmacokinetics were studied in beagle dogs using the core tablet and a micronized fenofibrate formulation as references. NLCs are released through the release orifices of the OPTs as integral nanoparticles. Near zero-order kinetics can be achieved by optimizing the influencing variables. After oral administration, decreased C max and steady drug levels for as long as over 24 h are observed. NLC-OPTs show an oral bioavailability of the model drug fenofibrate similar to that of the core tablets, which is about 1.75 folds that of a fast-release formulation. Controlled release of integral NLCs is achieved by the osmotic pump strategy.

  5. Long-term morphine delivery via slow release morphine pellets or osmotic pumps: Plasma concentration, analgesia, and naloxone-precipitated withdrawal.

    Science.gov (United States)

    McLane, Virginia D; Bergquist, Ivy; Cormier, James; Barlow, Deborah J; Houseknecht, Karen L; Bilsky, Edward J; Cao, Ling

    2017-09-15

    Slow-release morphine sulfate pellets and osmotic pumps are common routes of chronic morphine delivery in mouse models, but direct comparisons of these drug delivery systems are lacking. In this study, we assessed the efficacy of slow-release pellets versus osmotic pumps in delivering morphine to adult mice. Male C57BL/6NCr mice (8weeksold) were implanted subcutaneously with slow-release pellets (25mg morphine sulfate) or osmotic pumps (64mg/mL, 1.0μL/h). Plasma morphine concentrations were quantified via LC-MS/MS, analgesic efficacy was determined by tail flick assay, and dependence was assessed with naloxone-precipitated withdrawal behaviors (jumping) and physiological effects (excretion, weight loss). Morphine pellets delivered significantly higher plasma drug concentrations compared to osmotic pumps, which were limited by the solubility of the morphine sulfate and pump volume/flow rate. Within 96h post-implantation, plasma morphine concentrations were indistinguishable in pellet vs. pump-treated samples. While osmotic pump did not have an antinociceptive effect in the tail flick assay, pumps and pellets induced comparable dependence symptoms (naloxone-precipitated jumping behavior) from 24-72h post-implantation. In this study, we compared slow-release morphine pellets to osmotic minipumps for morphine delivery in mice. We found that osmotic pumps and subcutaneous morphine sulfate pellets yielded significantly different pharmacokinetics over a 7-day period, and as a result significantly different antinociceptive efficacy. Nonetheless, both delivery methods induced dependence as measured by naloxone-precipitated withdrawal. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Pre-compression volume on flow ripple reduction of a piston pump

    Science.gov (United States)

    Xu, Bing; Song, Yuechao; Yang, Huayong

    2013-11-01

    Axial piston pump with pre-compression volume(PCV) has lower flow ripple in large scale of operating condition than the traditional one. However, there is lack of precise simulation model of the axial piston pump with PCV, so the parameters of PCV are difficult to be determined. A finite element simulation model for piston pump with PCV is built by considering the piston movement, the fluid characteristic(including fluid compressibility and viscosity) and the leakage flow rate. Then a test of the pump flow ripple called the secondary source method is implemented to validate the simulation model. Thirdly, by comparing results among the simulation results, test results and results from other publications at the same operating condition, the simulation model is validated and used in optimizing the axial piston pump with PCV. According to the pump flow ripples obtained by the simulation model with different PCV parameters, the flow ripple is the smallest when the PCV angle is 13°, the PCV volume is 1.3×10-4 m3 at such operating condition that the pump suction pressure is 2 MPa, the pump delivery pressure 15 MPa, the pump speed 1 000 r/min, the swash plate angle 13°. At the same time, the flow ripple can be reduced when the pump suction pressure is 2 MPa, the pump delivery pressure is 5 MPa,15 MPa, 22 MPa, pump speed is 400 r/min, 1 000 r/min, 1 500 r/min, the swash plate angle is 11°, 13°, 15° and 17°, respectively. The finite element simulation model proposed provides a method for optimizing the PCV structure and guiding for designing a quieter axial piston pump.

  7. An atomistic methodology of energy release rate for graphene at nanoscale

    International Nuclear Information System (INIS)

    Zhang, Zhen; Lee, James D.; Wang, Xianqiao

    2014-01-01

    Graphene is a single layer of carbon atoms packed into a honeycomb architecture, serving as a fundamental building block for electric devices. Understanding the fracture mechanism of graphene under various conditions is crucial for tailoring the electrical and mechanical properties of graphene-based devices at atomic scale. Although most of the fracture mechanics concepts, such as stress intensity factors, are not applicable in molecular dynamics simulation, energy release rate still remains to be a feasible and crucial physical quantity to characterize the fracture mechanical property of materials at nanoscale. This work introduces an atomistic simulation methodology, based on the energy release rate, as a tool to unveil the fracture mechanism of graphene at nanoscale. This methodology can be easily extended to any atomistic material system. We have investigated both opening mode and mixed mode at different temperatures. Simulation results show that the critical energy release rate of graphene is independent of initial crack length at low temperature. Graphene with inclined pre-crack possesses higher fracture strength and fracture deformation but smaller critical energy release rate compared with the graphene with vertical pre-crack. Owing to its anisotropy, graphene with armchair chirality always has greater critical energy release rate than graphene with zigzag chirality. The increase of temperature leads to the reduction of fracture strength, fracture deformation, and the critical energy release rate of graphene. Also, higher temperature brings higher randomness of energy release rate of graphene under a variety of predefined crack lengths. The energy release rate is independent of the strain rate as long as the strain rate is small enough

  8. Controlled release of glaucocalyxin - a self-nanoemulsifying system from osmotic pump tablets with enhanced bioavailability.

    Science.gov (United States)

    Yanfei, Miao; Guoguang, Chen; Lili, Ren; Pingkai, Ouyang

    2017-03-01

    The purpose of this study was to develop a new formulation to enhance the bioavailability simultaneously with controlled release of glaucocalyxin A (GLA). In this study, controlled release of GLA was achieved by the osmotic release strategy taking advantage of the bioavailability enhancing capacity of self-nanoemulsifying drug delivery systems (SNEDDS). The formulation of GLA-SNEDDS was selected by the solubility and pseudoternary-phase diagrams studies. The prepared GLA-SNEDDS formulations were characterized for self-emulsification time, effect of pH and robustness to dilution, droplet size analysis and zeta potential. The optimized GLA-SNEDDS were used to prepare GLA-SNEDDS osmotic pump tablet via direct powder compression method. The effect of formulation variables on the release characteristic was investigated. GLA-SNEDDS osmotic pump tablets were administered to beagle dogs and their pharmacokinetics were compared to GLA and GLA-SNEDDS as a control. In vitro drug release studies indicated that the GLA-SNEDDS osmotic pump tablet showed sustained release profiles with 90% released within 12 h. Pharmacokinetic study showed steady blood GLA with prolonged T max and mean residence time (MRT), and enhanced bioavailability for GLA-SNEDDS osmotic pump tablet. It was concluded that simultaneous controlling on GLA release and enhanced bioavailability had been achieved by a combination of osmotic pump tablet and SNEDDS.

  9. Quarterly review of 241-SY-101 mixer pump data: January - March 1999; FINAL

    International Nuclear Information System (INIS)

    CONNER, J.M.

    1999-01-01

    This report presents data obtained on 241-SY-101 pump performance. The period covered is January 1 through March 31, 1999. During the quarter: There were changes in pumping parameters. Both the pump volute pressure and amperage decreased during the quarter. It is not clear whether this was due to changes in waste properties (due to less solids or more entrained gas) or due to degradation of the pump. There was an indication of a 7.5-inch increase in the waste level at riser 1 A, and an average growth rate of 0.082 inches per day. There was an indication of a 5.7-inch increase in the waste level at riser 1C. This riser was flushed with water several times, which would lower the level of the crust at this location. Gases continued to be released at less than the pre-pump installation baseline rate, indicating a decrease in the gas generation rate, or an increase in gas retention, or both. The release rate was about 78 percent of the rate in the previous few quarters, and only 34 percent of the generation rate calculated prior to mixer pump installation in 1993. Key controls exist for waste temperature, gas concentration, pump parameters, and long-term waste behavior associated with the safe operation of the mixer pump that mitigates the buoyant displacement gas release event behavior of 241-SY-101. Table 1-1 compares the key controls and the current state of the waste as of March 3 1. 1999. The pump was run 28 times between January 1 and March 31, 1999. All of the pump runs were intended to be normal 25-minute, 1000-rpm excavation runs performed to mix the waste and release gas. Because of the pump oil often reached the high temperature alarm setpoint of 190 F, many of the runs were shortened (by as many as 8 minutes). This phenomenon was identified in November 1998, but got progressively worse over the quarter. The pump schedule was nominally three runs per week. However, core sampling activities interrupted the usual pump schedule several times during the quarter

  10. Stabilization of diastolic calcium signal via calcium pump regulation of complex local calcium releases and transient decay in a computational model of cardiac pacemaker cell with individual release channels.

    Directory of Open Access Journals (Sweden)

    Alexander V Maltsev

    2017-08-01

    Full Text Available Intracellular Local Ca releases (LCRs from sarcoplasmic reticulum (SR regulate cardiac pacemaker cell function by activation of electrogenic Na/Ca exchanger (NCX during diastole. Prior studies demonstrated the existence of powerful compensatory mechanisms of LCR regulation via a complex local cross-talk of Ca pump, release and NCX. One major obstacle to study these mechanisms is that LCR exhibit complex Ca release propagation patterns (including merges and separations that have not been characterized. Here we developed new terminology, classification, and computer algorithms for automatic detection of numerically simulated LCRs and examined LCR regulation by SR Ca pumping rate (Pup that provides a major contribution to fight-or-flight response. In our simulations the faster SR Ca pumping accelerates action potential-induced Ca transient decay and quickly clears Ca under the cell membrane in diastole, preventing premature releases. Then the SR generates an earlier, more synchronized, and stronger diastolic LCR signal activating an earlier and larger inward NCX current. LCRs at higher Pup exhibit larger amplitudes and faster propagation with more collisions to each other. The LCRs overlap with Ca transient decay, causing an elevation of the average diastolic [Ca] nadir to ~200 nM (at Pup = 24 mM/s. Background Ca (in locations lacking LCRs quickly decays to resting Ca levels (<100 nM at high Pup, but remained elevated during slower decay at low Pup. Release propagation is facilitated at higher Pup by a larger LCR amplitude, whereas at low Pup by higher background Ca. While at low Pup LCRs show smaller amplitudes, their larger durations and sizes combined with longer transient decay stabilize integrals of diastolic Ca and NCX current signals. Thus, the local interplay of SR Ca pump and release channels regulates LCRs and Ca transient decay to insure fail-safe pacemaker cell operation within a wide range of rates.

  11. Gas release during salt well pumping: model predictions and comparisons to laboratory experiments

    International Nuclear Information System (INIS)

    Peurrung, L.M.; Caley, S.M.; Bian, E.Y.; Gauglitz, P.A.

    1996-09-01

    The Hanford Site has 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. Some of these wastes are known to generate mixtures of flammable gases, including hydrogen, nitrous oxide, and ammonia. Nineteen of these SSTs have been placed on the Flammable Gas Watch List (FGWL) because they are known or suspected, in all but one case, to retain these flammable gases. Salt well pumping to remove the interstitial liquid from SSTs is expected to cause the release of much of the retained gas, posing a number of safety concerns. Research at the Pacific Northwest National Laboratory (PNNL) has sought to quantify the release of flammable gases during salt well pumping operations. This study is being conducted for Westinghouse Hanford Company as part of the PNNL Flammable Gas Project. Understanding and quantifying the physical mechanisms and waste properties that govern gas release during salt well pumping will help to resolve the associated safety issues

  12. Rapid release of 42K or 86Rb from two distinct transport sites on the Na,K-pump in the presence of Pi or vanadate

    International Nuclear Information System (INIS)

    Forbush, B. III

    1987-01-01

    The rate of 86Rb or 42 K release from an occluded form of the phosphorylated Na+ pump has been studied using a rapid filtration apparatus described previously. The rate constant of release is 5-15 s-1, and 42 K and 86Rb dissociate at approximately the same rate. Mg2+ is required for deocclusion in the presence of Pi at a site which has the same affinity as the site involved in stabilization of E2(K) with ATP; we propose that Na,K-ATPase has only one site for Mg2+, that the affinity of this site for Mg2+ is increased by Pi binding and decreased by ATP binding, and that Mg2+ is bound and released in the normal transport cycle. In the presence of K+, Cs+, Rb+, or Tl+, the release of two distinct 86Rb ions can be observed, the slow release from one site (''s'' site) being blocked by occupancy of the site vacated by the other (''f'', fast site). By a sequence of incubations, labeled 86Rb can be placed at either site, and the rate of dissociation monitored individually; in the absence of K+, dissociation from the s site proceeds after a lag in which the f site is vacated. The results are consistent with a ''flickering-gate'' model of deocclusion to the extracellular pump face, in which the site is exposed to the medium only long enough for a single ion to be released. When deocclusion to the intracellular face is promoted with ATP, ions are released from both sites at the same rate, presumably because the E2----E1 conformational change is rate-limiting. Unlabeled ions co-occluded with 86Rb increase the ATP-stimulated rate of release in the order Rb+ less than Tl+ less than Cs+ less than K+; since the same rank order is observed when dissociation from the s site is monitored in the presence of these ions and MgPi we propose that the latter process proceeds toward the intracellular pump face

  13. Adsorption pump for helium pumping out

    International Nuclear Information System (INIS)

    Donde, A.L.; Semenenko, Yu.E.

    1981-01-01

    Adsorption pump with adsorbent cooling by liquid helium is described. Shuttered shield protecting adsorbent against radiation is cooled with evaporating helium passing along the coil positioned on the shield. The pump is also equipped with primed cylindrical shield, cooled with liquid nitrogen. The nitrogen shield has in the lower part the shuttered shield, on the pump casing there is a valve used for pump pre-burning, and valves for connection to recipient as well. Pumping- out rates are presented at different pressures and temperatures of adsorbent. The pumping-out rate according to air at absorbent cooling with liquid nitrogen constituted 5x10 -4 Pa-3000 l/s, at 2x10 -2 Pa-630 l/s. During the absorbent cooling with liquid hydrogen the pumping-out rate according to air was at 4x10 -4 Pa-580 l/s, at 2x10 -3 Pa-680 l/s, according to hydrogen - at 8x10 -5 Pa-2500 l/s, at 5x10 -3 Pa-4200 l/s. During adsorbent cooling with liquid helium the rate of pumping-out according to hydrogen at 3x10 5 Pa-2400% l/s, at 6x10 3 Pa-1200 l/s, and according to helium at 3.5x10 -5 Pa-2800 l/s, at 4x10 -3 Pa-1150 l/s. The limit vacuum is equal to 1x10 -7 Pa. The volume of the vessel with liquid helium is equal to 3.5 l. Helium consumption is 80 cm 3 /h. Consumption of liquid nitrogen from the shield is 400 cm 3 /h. The limit pressure in the pump is obtained after forevacuum pumping-out (adsorbent regeneration) at 300 K temperature. The pump is made of copper. The pump height together with primed tubes is 800 mm diameter-380 mm [ru

  14. Building Adjustable Pre-storm Reservoir Flood-control Release Rules

    Science.gov (United States)

    Yang, Shun-Nien; Chang, Li-Chiu; Chang, Fi-John; Hsieh, Cheng-Daw

    2017-04-01

    Typhoons hit Taiwan several times every year, which could cause serious flood disasters. Because mountainous terrains and steep landforms can rapidly accelerate the speed of flood flow during typhoon events, rivers cannot be a stable source of water supply. Reservoirs become the most effective floodwater storage facilities for alleviating flood damages in Taiwan. The pre-storm flood-control release can significantly increase reservoir storage capacity available to store floodwaters for reducing downstream flood damage, while the uncertainties of total forecasted rainfalls are very high in different stages of an oncoming typhoon, which may cause the risk of water shortage in the future. This study proposes adjustable pre-storm reservoir flood-control release rules in three designed operating stages with various hydrological conditions in the Feitsui Reservoir, a pivot reservoir for water supply to Taipei metropolitan in Taiwan, not only to reduce the risk of reservoir flood control and downstream flooding but also to consider water supply. The three operating stages before an oncoming typhoon are defined upon the timings when: (1) typhoon news is issued (3-7days before typhoon hit); (2) the sea warning is issued (2-4 days before typhoon hit); and (3) the land warning is issued (1-2 days before typhoon hit). We simulate 95 historical typhoon events with 3000 initial water levels and build some pre-storm flood-control release rules to adjust the amount of pre-release based on the total forecasted rainfalls at different operating stages. A great number of simulations (68.4 millions) are conducted to extract their major consequences and then build the adjustable pre-storm reservoir flood-control release rules. Accordingly, given a total forecasted rainfall and a water level, reservoir decision makers can easily identify the corresponding rule to tell the amount of pre-release in any stage. The results show that the proposed adjustable pre-release rules can effectively

  15. High energy high repetition-rate thin-disk amplifier for OPCPA pumping

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Michael

    2013-08-15

    The development of a pump laser system for a high power and high repetition rate optical parametric chirped-pulse amplification (OPCPA) is presented in this thesis. The OPCPA system requires pump pulse energies in the range of tens of millijoules at high repetition rates with sub-picosecond pulse durations. This can be achieved to some extend with Innoslab amplifier technology. However, scaling to higher pulse energies at high repetition rates may be problematic. With the thin-disk amplifier presented in this thesis, output energies of 140 mJ at 100 kHz repetition rate could be achieved in burst-mode operation, which is a world record for this type of laser amplifier. Due to its material and spectral properties, ytterbium doped YAG (Yb:YAG) is used as a gain medium for the high power amplifier stages. The low quantum defect and the comparatively large emission bandwidth makes this material the choice for high power operation and sub-picosecond compressed pulse durations. The output beam profile as well as the shape of the output bursts is ideal to pump an OPCPA system. An OPCPA output energy in the millijoule range with repetition rates of 100 kHz to 1 MHz is needed to generate seed pulses for the FEL and for the application as pump-probe laser at the FEL facility. Since the development of this laser system needs to meet requirements set by the Free-Electron Laser in Hamburg (FLASH), the amplifier is conceived for burst-mode operation. The main requirement is a high intra-burst pulse repetition rate of more than 100 kHz and a uniform pulse train (burst) with equal properties for every pulse. The burst-mode is an operation mode where the laser never reaches a lasing equilibrium, which means that the behavior of the amplifier is similar to a switch-on of the laser system for every burst. This makes the development of the amplifier system difficult. Therefore, an analytical model has been developed to study the amplification process during the burst. This includes the

  16. High energy high repetition-rate thin-disk amplifier for OPCPA pumping

    International Nuclear Information System (INIS)

    Schulz, Michael

    2013-08-01

    The development of a pump laser system for a high power and high repetition rate optical parametric chirped-pulse amplification (OPCPA) is presented in this thesis. The OPCPA system requires pump pulse energies in the range of tens of millijoules at high repetition rates with sub-picosecond pulse durations. This can be achieved to some extend with Innoslab amplifier technology. However, scaling to higher pulse energies at high repetition rates may be problematic. With the thin-disk amplifier presented in this thesis, output energies of 140 mJ at 100 kHz repetition rate could be achieved in burst-mode operation, which is a world record for this type of laser amplifier. Due to its material and spectral properties, ytterbium doped YAG (Yb:YAG) is used as a gain medium for the high power amplifier stages. The low quantum defect and the comparatively large emission bandwidth makes this material the choice for high power operation and sub-picosecond compressed pulse durations. The output beam profile as well as the shape of the output bursts is ideal to pump an OPCPA system. An OPCPA output energy in the millijoule range with repetition rates of 100 kHz to 1 MHz is needed to generate seed pulses for the FEL and for the application as pump-probe laser at the FEL facility. Since the development of this laser system needs to meet requirements set by the Free-Electron Laser in Hamburg (FLASH), the amplifier is conceived for burst-mode operation. The main requirement is a high intra-burst pulse repetition rate of more than 100 kHz and a uniform pulse train (burst) with equal properties for every pulse. The burst-mode is an operation mode where the laser never reaches a lasing equilibrium, which means that the behavior of the amplifier is similar to a switch-on of the laser system for every burst. This makes the development of the amplifier system difficult. Therefore, an analytical model has been developed to study the amplification process during the burst. This includes the

  17. Campaign for A-rated circulator pumps - a proven strategy

    Energy Technology Data Exchange (ETDEWEB)

    Lueders, Christian; Wilke, Goeran (The Danish Electricity Saving Trust (Denmark)); Dam Wied, Martin (Wormslev - NRGi Raadgivning A/S (Denmark))

    2009-07-01

    1.2 million households in Denmark have a central heating circulator pump. An estimated 800,000 pumps installed are old and inefficient. Potential savings per year of 400 GWh and 200,000 tons of CO{sub 2} can be achieved by replacing these obsolete pumps. However, many consumers and installers have neither an opinion about, nor play an active role in choosing a circulator pump. This paper documents how it is possible to promote the wider use of A-rated circulator pumps via an offensive campaign strategy to get both consumers and installers to participate actively in the choice of pump, thereby increasing the market share of A-rated pumps sold. The campaign is based on a broadly-based push-pull strategy which aims to influence both consumers and suppliers simultaneously. The strategy consists of the following elements: Involvement of the supply side via voluntary agreements with producers, wholesalers, installers, and their trade organisations; Partnerships with installers in order to secure fixed price installations for A-rated pumps; Influencing consumers through magazine advertisements and TV commercials. The market share for A-rated circulator pumps in Denmark grew from 15-60% in the period January 2006 to the end of October 2008. In a new phase, the strategy is switching the focus to OEM and boiler producers, and producers of heat exchangers for district and underfloor heating systems. The aim of the current phase was for A pumps to have accounted for 60% of the Danish market by the end of 2008

  18. Failure cause and failure rate evaluation on pumps of BWR plants in PSA. Hypothesis testing for typical or plant specific failure rate of pumps

    International Nuclear Information System (INIS)

    Sanada, Takahiro; Nakamura, Makoto

    2009-01-01

    In support of domestic nuclear industry effort to gather and analyze failure data of components concerning nuclear power plants, Nuclear Information Archives (NUCIA) are published for useful information to help PSA. This report focuses on NUCIA pertaining to pumps in domestic nuclear power plants, and provides the reliable estimation on failure rate of pumps resulting from failure cause analysis and hypothesis testing of classified and plant specific failure rate of pumps for improving quality in PSA. The classified and plant specific failure rate of pumps are estimated by analyzing individual domestic nuclear power plant's data of 26 Boiling Water Reactors (BWRs) concerning functionally structurally classified pump failures reported from beginning of commercial operation to March 31, 2007. (author)

  19. Flow Rate In Microfluidic Pumps As A Function Of Tension and Pump Motor Head Speed

    Science.gov (United States)

    Irwin, Anthony; McBride, Krista

    2015-03-01

    As the use of microfluidic devices has become more common in recent years the need for standardization within the pump systems has grown. The pumps are ball bearing rotor microfluidic pumps and work off the idea of peristalsis. The rapid contraction and relaxation propagating down a tube or a microfluidic channel. The ball bearings compress the tube (occlusion) and move along part of the tube length forcing fluid to move inside of the tube in the same direction of the ball bearings. When the ball bearing rolls off the area occupied by the microfluidic channel, its walls and ceiling undergo restitution and a pocket of low pressure is briefly formed pulling more of the liquid into the pump system. Before looking to standardize the pump systems it must be known how the tension placed by the pumps bearing heads onto the PDMS inserts channels affect the pumps performance (mainly the flow rate produced). The relationship of the speed at which the bearings on the motor head spin and the flow rate must also be established. This research produced calibration curves for flow rate vs. tension and rpm. These calibration curves allow the devices to be set to optimal user settings by simply varying either the motor head tension or the motor head speed. I would like to acknowledge the help and support of Vanderbilt University SyBBURE program, Christina Marasco, Stacy Sherod, Franck Block and Krista McBride.

  20. Operation and control strategies in pre-series testing of cold circulating pumps for ITER

    International Nuclear Information System (INIS)

    Bhattacharya, R.; Vaghela, H.; Sarkar, B.; Srinivas, M.; Choukekar, K.

    2013-01-01

    Cryo-distribution system of ITER is responsible for the distribution and control of forced-flow supercritical helium for cooling of the superconducting magnets and the cryo-pumps. The requirements of cold circulating pumps (CCP) for mass flow rates and performance are much higher than presently existing and commercially available one used at 4.0 K helium. Design up-scaling with pre-series test of CCP has been proposed including test infrastructure. Operation and control strategies for the test distribution box (TDB) of test infrastructure have been developed and analyzed using steady state and dynamic process simulation to cope with the functional requirements of CCPs. Off-normal scenario with CCP inlet pressure variation is an important concern, dynamic process responses during such scenario have been evaluated to verify the operability of CCP. The paper describes process simulation to cope with the functional requirements of CCPs along with evaluation of off-normal scenario to verify the operability of CCP. (author)

  1. Buprenorphine dose induction in non-opioid-tolerant pre-release prisoners.

    Science.gov (United States)

    Vocci, Frank J; Schwartz, Robert P; Wilson, Monique E; Gordon, Michael S; Kinlock, Timothy W; Fitzgerald, Terrence T; O'Grady, Kevin E; Jaffe, Jerome H

    2015-11-01

    In a previously reported randomized controlled trial, formerly opioid-dependent prisoners were more likely to enter community drug abuse treatment when they were inducted in prison onto buprenorphine/naloxone (hereafter called buprenorphine) than when they received counseling without buprenorphine in prison (47.5% vs. 33.7%, p=0.012) (Gordon et al., 2014). In this communication we report on the results of the induction schedule and the adverse event profile seen in pre-release prisoners inducted onto buprenorphine. This paper examines the dose induction procedure, a comparison of the proposed versus actual doses given per week, and side effects reported for 104 adult participants who were randomized to buprenorphine treatment in prison. Self-reported side effects were analyzed using generalized estimated equations to determine changes over time in side effects. Study participants were inducted onto buprenorphine at a rate faster than the induction schedule. Of the 104 (72 males, 32 females) buprenorphine recipients, 64 (37 males, 27 females) remained on medication at release from prison. Nine participants (8.6%) discontinued buprenorphine because of unpleasant opioid side effects. There were no serious adverse events reported during the in-prison phase of the study. Constipation was the most frequent symptom reported (69 percent). Our findings suggest that buprenorphine administered to non-opioid-tolerant adults should be started at a lower, individualized dose than customarily used for adults actively using opioids, and that non-opioid-tolerant pre-release prisoners can be successfully inducted onto therapeutic doses prior to release. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. The flow Rate Accuracy of Elastomeric Infusion Pumps After Repeated Filling.

    Science.gov (United States)

    Mohseni, Masood; Ebneshahidi, Amin

    2014-05-01

    One of the frequent applications of elastomeric infusion pumps is postoperative pain management. In daily practice, the disposable pumps get refilled with modified medication combinations in the successive days; although, the accuracy of infusion rates is unknown to clinicians. Our aim was to evaluate the effect of repeated filling on the delivery rate accuracy of an elastomeric pump available in our market. We examined 10 elastomeric infusion pumps (BOT-802, Nanchang Biotek Medical Device Company, China) with 100 mL capacity and nominal flow of 5 mL/h. Each pump was filled for three times, accounting for 30 series of experiments. A microset scaled in mL was used to measure the pump deliveries. Flow profile and reliability of infusion rate were analyzed after repeated use. The mean flow rate in the three series of measurements showed a gradual increase; however, the difference was not statistically significant (5.01 ± 0.07 vs. 5.03 ± 0.06 vs. 5.06 ± 0.08 mL/h; P = 0.81). The percentage of the flow rate error (deviation from 5 mL/h ± 15%) was 100% in the first and second hours of infusion, 96% in the third hour, 60% in the 20th hour and zero percent in the rest of the infusion time. This study indicated that the delivery rate accuracy of elastomeric infusion pumps is preserved after repeated usage. These laboratory findings suggested that elastomeric pumps could be safely refilled in the successive days to provide postoperative analgesia.

  3. Sodium flow rate measurement method of annular linear induction pumps

    International Nuclear Information System (INIS)

    Araseki, Hideo; Kirillov, Igor R.; Preslitsky, Gennady V.

    2012-01-01

    Highlights: ► We found a new method of flow rate monitoring of electromagnetic pump. ► The method is very simple and does not require a large space. ► The method was verified with an experiment and a numerical analysis. ► The experimental data and the numerical results are in good agreement. - Abstract: The present paper proposes a method for measuring sodium flow rate of annular linear induction pumps. The feature of the method lies in measuring the leaked magnetic field with measuring coils near the stator end on the outlet side and in correlating it with the sodium flow rate. This method is verified through an experiment and a numerical analysis. The data obtained in the experiment reveals that the correlation between the leaked magnetic field and the sodium flow rate is almost linear. The result of the numerical analysis agrees with the experimental data. The present method will be particularly effective to sodium flow rate monitoring of each one of plural annular linear induction pumps arranged in parallel in a vessel which forms a large-scale pump unit.

  4. Statistical analysis of nuclear power plant pump failure rate variability: some preliminary results

    International Nuclear Information System (INIS)

    Martz, H.F.; Whiteman, D.E.

    1984-02-01

    In-Plant Reliability Data System (IPRDS) pump failure data on over 60 selected pumps in four nuclear power plants are statistically analyzed using the Failure Rate Analysis Code (FRAC). A major purpose of the analysis is to determine which environmental, system, and operating factors adequately explain the variability in the failure data. Catastrophic, degraded, and incipient failure severity categories are considered for both demand-related and time-dependent failures. For catastrophic demand-related pump failures, the variability is explained by the following factors listed in their order of importance: system application, pump driver, operating mode, reactor type, pump type, and unidentified plant-specific influences. Quantitative failure rate adjustments are provided for the effects of these factors. In the case of catastrophic time-dependent pump failures, the failure rate variability is explained by three factors: reactor type, pump driver, and unidentified plant-specific influences. Finally, point and confidence interval failure rate estimates are provided for each selected pump by considering the influential factors. Both types of estimates represent an improvement over the estimates computed exclusively from the data on each pump

  5. Groundwater heat pump performance improvement with pre-coolers and pump modification: Final report for the 1985-86 SOMED (School of Mines and Energy Development) project year

    Energy Technology Data Exchange (ETDEWEB)

    Kavanaugh, S.

    1986-09-30

    Improved performance of groundwater heat pumps can be realized with a more effective and efficient utilization of the thermal properties of shallow groundwater. These systems circulate water from aquifers through water source heat pumps to achieved high efficiencies and capacities. This project concludes that a 10 to 15 percent cooling performance improvement can be realized by pre-cooling the room air with the 55/sup 0/ to 67/sup 0/F groundwater available in large portions of the Southeast. Proper design of these pre-coolers eliminates unnecessary auxiliary energy requirements. The efficiency of the overall system can be further improved with modifications to current methods of water circulation system design. Pressure requirements are minimized by maintaining a low unit inlet pressure (8 psig maximum), removing unnecessary loop restrictions and injection below the water table. Standard submersible water pumps exceed the resulting required size for residential groundwater heat pumps. Simple modifications can be made by the manufacturer to correct this problem. The result is an overall 15 to 40 percent performance improvement over high efficiency air source heat pumps with a simple payback of between 0 to 10 years in most cases.

  6. Activation of the Na+/K(+)-pump in rat peritoneal mast cells following histamine release: a possible role in cell recovery

    DEFF Research Database (Denmark)

    Knudsen, T; Ferjan, I; Johansen, Torben

    1993-01-01

    1. The activity of the Na+/K(+)-pump in rat peritoneal mast cells was measured at various time intervals after induction of cellular histamine release by compound 48/80 or by the antigen-antibody reaction. The Na+/K(+)-pump activity was assessed as the ouabain-sensitive potassium uptake....... On the basis of the present results, we suggest a role for the Na+/K(+)-pump in the recovery process of the mast cell following histamine release....... of the cells using 86Rb+ as a tracer for potassium (K+(86Rb+)-uptake). 2. Stimulation of the cells with compound 48/80 induced a time and concentration dependent increase of the Na+/K(+)-pump activity. The pump activity was maximal 2 min after stimulation of the cells. Then, the activity gradually decreased...

  7. 3D finite element analysis of stress distributions and strain energy release rates for adhesive bonded flat composite lap shear joints having pre-existing delaminations

    Energy Technology Data Exchange (ETDEWEB)

    Parida, S. K.; Pradhan, A. K. [Indian Institute of Technology, Bhubaneswar (India)

    2014-02-15

    The rate of propagation of embedded delamination in the strap adherend of lap shear joint (LSJ) made of carbon/epoxy composites has been evaluated employing three-dimensional non-linear finite elements. The delamination has been presumed to pre-exist in the thin resin layer between the first and second plies of the strap adherend. The inter-laminar peel and shear stress distributions have been studied in details and are seen to be predominantly three-dimensional in nature. The components of strain energy release rate (SERR) corresponding to the opening, sliding and cross sliding modes of delamination are significantly different at the two fronts of the embedded delamination. The sequential release of multi-point constraint (MPC) finite elements in the vicinity of the delamination fronts enables to simulate the growth of the delamination at either ends. This simulation procedure can be utilized effectively for evaluation of the status of the structural integrity of the bonded joints.

  8. Neutral pumping rates for a next step tokamak ignition device

    International Nuclear Information System (INIS)

    Galambos, J.D.; Peng, Y.K.M.; Heifetz, D.

    1985-01-01

    Neutral pumping rates are calculated for pump-limiter and divertor options of a next step tokamak ignition device using a method that accounts for the coupled effects of neutral transport and plasma transport. For both pump limiters and divertors the plasma flow into the channel surrounding the neutralizer plate is greatly reduced by the neutral recycling. The fraction of this flow that is pumped can be large (>50%) but in general is dependent on the particular geometry and plasma conditions. It is estimated that pumping speeds greater than or approximately 10 5 L/s are adequate for the exhaust requirements in the pump-limiter and the divertor cases

  9. Effect of Non-linear Velocity Loss Changes in Pumping Stage of Hydraulic Ram Pumps on Pumping Discharge Rate

    Directory of Open Access Journals (Sweden)

    Reza Fatahialkouhi

    2018-03-01

    the previous researchers. Comparing the results indicates that in the proposed model, noticing that the recommended equations of pumping stage are presented based on nonlinear closing theory of the impulse valve, the model accuracy for predicting relative pumping rate has been increased up to 3% compared with linear closure theory (Lansford and Dugan, 1941 and has been increased up to 5% compared with rapid closure theory (Tacke, 1988.

  10. Rapid release of 42K and 86Rb from an occluded state of the Na,K-pump in the presence of ATP or ADP

    International Nuclear Information System (INIS)

    Forbush, B. III

    1987-01-01

    We have measured the time course of release of 42 K and 86 Rb from an occluded state of the Na,K-pump using a rapid filtration apparatus. We have found that at 20 degrees C and in the presence of ATP, 42 K is released with a rate constant of approximately 45 s-1 and 86 Rb with a rate constant of approximately 20 s-1; both ATP and ADP are effective at a low affinity site (Kd approximately 0.3 and 1 mM, respectively) with the rate of deocclusion being only half as great in ADP as in ATP. Mg2+ stimulates 2-fold at low concentrations probably by forming MgATP, and free Mg2+ is strongly inhibitory at high concentrations (Kd approximately 10 mM). Mg2+ also decreases the affinity for ATP, and the data are consistent with mixed type inhibition; from the analysis the dissociation constant is approximately 1 mM for the inhibitory Mg2+ and the Rb+-occluded form without ATP. The rate of 42 K or 86 Rb release increases monotonically with pH while ATPase activity decreases above pH 8, so that deocclusion is not rate-limiting in the overall cycle at high pH. This is reflected by a convergence of the rate of Na,K-ATPase and Na,Rb-ATPase activities at high pH and by a decrease in the observed steady-state level of the occluded 86 Rb intermediate at high pH. K+, Rb+, Na+, and Cs+, but not Li+, increase the rate of 42 K and 86 Rb release at constant ionic strength, presumably at sites other than the transport sites. The spontaneous rate of deocclusion is only approximately 0.1 s-1 at low ionic strength in the absence of nucleotides, and it is increased markedly by all cations tested except Li+. Overall the data are consistent with deocclusion as a rate-limiting step in the Na,K-pump cycle

  11. Extended-release naltrexone for pre-release prisoners: A randomized trial of medical mobile treatment

    Science.gov (United States)

    Gordon, Michael S.; Vocci, Frank J.; Fitzgerald, Terrence T.; O'Grady, Kevin E.; O'Brien, Charles P.

    2017-01-01

    Background Extended-release naltrexone (XR-NTX), is an effective treatment for opioid use disorder but is rarely initiated in US prisons or with criminal justice populations. Mobile treatment for chronic diseases have been implemented in a variety of settings. Mobile treatment may provide an opportunity to expand outreach to parolees to surmount barriers to traditional clinic treatment. Methods Male and female prisoners (240) with pre-incarceration histories of opioid use disorder who are within one month of release from prison will be enrolled in this randomized clinical trial. Participants are randomized to one of two study arms: 1) [XR-NTX-OTx] One injection of long-acting naltrexone in prison, followed by 6 monthly injections post-release at a community opioid treatment program; or 2) [XR-NTX+ MMTx] One injection of long-acting naltrexone in prison followed by 6 monthly injections post-release at the patient's place of residence utilizing mobile medical treatment. The primary outcomes are: treatment adherence; opioid use; criminal activity; re-arrest; reincarceration; and HIV risk-behaviors. Results We describe the background and rationale for the study, its aims, hypotheses, and study design. Conclusions The use of long-acting injectable naltrexone may be a promising form of treatment for pre-release prisoners. Finally, as many individuals in the criminal justice system drop out of treatment, this study will assess whether treatment at their place of residence will improve adherence and positively affect treatment outcomes. PMID:28011389

  12. Extended-release naltrexone for pre-release prisoners: A randomized trial of medical mobile treatment.

    Science.gov (United States)

    Gordon, Michael S; Vocci, Frank J; Fitzgerald, Terrence T; O'Grady, Kevin E; O'Brien, Charles P

    2017-02-01

    Extended-release naltrexone (XR-NTX), is an effective treatment for opioid use disorder but is rarely initiated in US prisons or with criminal justice populations. Mobile treatment for chronic diseases has been implemented in a variety of settings. Mobile treatment may provide an opportunity to expand outreach to parolees to surmount barriers to traditional clinic treatment. Male and female prisoners (240) with pre-incarceration histories of opioid use disorder who are within one month of release from prison will be enrolled in this randomized clinical trial. Participants are randomized to one of two study arms: 1) [XR-NTX-OTx] One injection of long-acting naltrexone in prison, followed by 6 monthly injections post-release at a community opioid treatment program; or 2) [XR-NTX+ MMTx] One injection of long-acting naltrexone in prison followed by 6 monthly injections post-release at the patient's place of residence utilizing mobile medical treatment. The primary outcomes are: treatment adherence; opioid use; criminal activity; re-arrest; reincarceration; and HIV risk-behaviors. We describe the background and rationale for the study, its aims, hypotheses, and study design. The use of long-acting injectable naltrexone may be a promising form of treatment for pre-release prisoners. Finally, as many individuals in the criminal justice system drop out of treatment, this study will assess whether treatment at their place of residence will improve adherence and positively affect treatment outcomes. ClinicalTrials.gov: NCT02867124. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Size-fractionated characterization and quantification of nanoparticle release rates from a consumer spray product containing engineered nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hagendorfer, Harald, E-mail: Harald.Hagendorfer@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland); Lorenz, Christiane, E-mail: Christiane.Lorenz@chem.ethz.c [ETHZ, Swiss Federal Institute of Technology Zurich (Switzerland); Kaegi, Ralf, E-mail: Ralf.Kaegi@eawag.ch; Sinnet, Brian, E-mail: Brian.Sinnet@eawag.c [EAWAG, Swiss Federal Institute of Aquatic Science and Technology (Switzerland); Gehrig, Robert, E-mail: Robert.Gehrig@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland); Goetz, Natalie V., E-mail: Natalie.vonGoetz@chem.ethz.ch; Scheringer, Martin, E-mail: Martin.Scheringer@chem.ethz.c [ETHZ, Swiss Federal Institute of Technology Zurich (Switzerland); Ludwig, Christian, E-mail: Christian.Ludwig@psi.c [PSI, Paul Scherrer Institue (Switzerland); Ulrich, Andrea, E-mail: Andrea.Ulrich@empa.c [EMPA, Swiss Federal Laboratories for Materials Testing and Research (Switzerland)

    2010-09-15

    This study describes methods developed for reliable quantification of size- and element-specific release of engineered nanoparticles (ENP) from consumer spray products. A modified glove box setup was designed to allow controlled spray experiments in a particle-minimized environment. Time dependence of the particle size distribution in a size range of 10-500 nm and ENP release rates were studied using a scanning mobility particle sizer (SMPS). In parallel, the aerosol was transferred to a size-calibrated electrostatic TEM sampler. The deposited particles were investigated using electron microscopy techniques in combination with image processing software. This approach enables the chemical and morphological characterization as well as quantification of released nanoparticles from a spray product. The differentiation of solid ENP from the released nano-sized droplets was achieved by applying a thermo-desorbing unit. After optimization, the setup was applied to investigate different spray situations using both pump and gas propellant spray dispensers for a commercially available water-based nano-silver spray. The pump spray situation showed no measurable nanoparticle release, whereas in the case of the gas spray, a significant release was observed. From the results it can be assumed that the homogeneously distributed ENP from the original dispersion grow in size and change morphology during and after the spray process but still exist as nanometer particles of size <100 nm. Furthermore, it seems that the release of ENP correlates with the generated aerosol droplet size distribution produced by the spray vessel type used. This is the first study presenting results concerning the release of ENP from spray products.

  14. Size-fractionated characterization and quantification of nanoparticle release rates from a consumer spray product containing engineered nanoparticles

    International Nuclear Information System (INIS)

    Hagendorfer, Harald; Lorenz, Christiane; Kaegi, Ralf; Sinnet, Brian; Gehrig, Robert; Goetz, Natalie V.; Scheringer, Martin; Ludwig, Christian; Ulrich, Andrea

    2010-01-01

    This study describes methods developed for reliable quantification of size- and element-specific release of engineered nanoparticles (ENP) from consumer spray products. A modified glove box setup was designed to allow controlled spray experiments in a particle-minimized environment. Time dependence of the particle size distribution in a size range of 10-500 nm and ENP release rates were studied using a scanning mobility particle sizer (SMPS). In parallel, the aerosol was transferred to a size-calibrated electrostatic TEM sampler. The deposited particles were investigated using electron microscopy techniques in combination with image processing software. This approach enables the chemical and morphological characterization as well as quantification of released nanoparticles from a spray product. The differentiation of solid ENP from the released nano-sized droplets was achieved by applying a thermo-desorbing unit. After optimization, the setup was applied to investigate different spray situations using both pump and gas propellant spray dispensers for a commercially available water-based nano-silver spray. The pump spray situation showed no measurable nanoparticle release, whereas in the case of the gas spray, a significant release was observed. From the results it can be assumed that the homogeneously distributed ENP from the original dispersion grow in size and change morphology during and after the spray process but still exist as nanometer particles of size <100 nm. Furthermore, it seems that the release of ENP correlates with the generated aerosol droplet size distribution produced by the spray vessel type used. This is the first study presenting results concerning the release of ENP from spray products.

  15. Stress Introduction Rate Alters the Benefit of AcrAB-TolC Efflux Pumps.

    Science.gov (United States)

    Langevin, Ariel M; Dunlop, Mary J

    2018-01-01

    Stress tolerance studies are typically conducted in an all-or-none fashion. However, in realistic settings-such as in clinical or metabolic engineering applications-cells may encounter stresses at different rates. Therefore, how cells tolerate stress may depend on its rate of appearance. To address this, we studied how the rate of stress introduction affects bacterial stress tolerance by focusing on a key stress response mechanism. Efflux pumps, such as AcrAB-TolC of Escherichia coli , are membrane transporters well known for the ability to export a wide variety of substrates, including antibiotics, signaling molecules, and biofuels. Although efflux pumps improve stress tolerance, pump overexpression can result in a substantial fitness cost to the cells. We hypothesized that the ideal pump expression level would involve a rate-dependent trade-off between the benefit of pumps and the cost of their expression. To test this, we evaluated the benefit of the AcrAB-TolC pump under different rates of stress introduction, including a step, a fast ramp, and a gradual ramp. Using two chemically diverse stresses, the antibiotic chloramphenicol and the jet biofuel precursor pinene, we assessed the benefit provided by the pumps. A mathematical model describing these effects predicted the benefit as a function of the rate of stress introduction. Our findings demonstrate that as the rate of introduction is lowered, stress response mechanisms provide a disproportionate benefit to pump-containing strains, allowing cells to survive beyond the original inhibitory concentrations. IMPORTANCE Efflux pumps are ubiquitous in nature and provide stress tolerance in the cells of species ranging from bacteria to mammals. Understanding how pumps provide tolerance has far-reaching implications for diverse fields, from medicine to biotechnology. Here, we investigated how the rate of stressor appearance impacts tolerance. We focused on two distinct substrates of AcrAB-TolC efflux pumps, the

  16. Observation of advanced particle removal rates in pump limiter simulation experiments

    International Nuclear Information System (INIS)

    Goebel, D.M.; Conn, R.W.

    1984-05-01

    The performance of particle removal schemes for density and impurity control in tokamaks and mirror machines depends strongly on the plasma parameters and local recycling near the plasma neutralizier plates and gas pumping ducts. The relationship between plasma density, electron temperature, ion energy and gas flow and particle removal rate through a pumping duct located near a plasma neutralizer plate has been experimentally investigated in the steady state plasma device PISCES. Results indicate that initially the particle removal by pumps at the end of the duct is proportional to the plasma flux to the plate. A nonlinear increase in the pumping rate occurs when the ionization mean free path for neutrals from the plate becomes less than the plasma radius. The transition from a transparent to an opaque plasma due to local ionization of the neutrals produced at the neutralizer plate greatly enhances the particle removal rate by recycling of the neutral gas as it flows away from the neutralizer plate or out of the pumping ducts. Parameters were varied to determine the importance of ballistic scattering of higher energy ions from the plate, but no effects were found in these experiments

  17. B16-BL6 melanoma cells release inhibitory factor(s) of active pump activity in isolated lymph vessels.

    Science.gov (United States)

    Nakaya, K; Mizuno, R; Ohhashi, T

    2001-12-01

    We investigated whether supernatant cultured with melanoma cell lines B16-BL6 and K1735 or the Lewis lung carcinoma cell line (LLC) can regulate lymphatic pump activity with bioassay preparations isolated from murine iliac lymph vessels. B16-BL6 and LLC supernatants caused significant dilation of lymph microvessels with cessation of pump activity. B16-BL6 supernatant produced dose-related cessation of lymphatic pump activity. There was no significant tachyphylaxis in the supernatant-mediated inhibitory response of lymphatic pump activity. Pretreatment with 3 x 10(-5) M N(omega)-nitro-L-arginine methyl ester (L-NAME) or 10(-7) M or 10(-6) M glibenclamide and 5 x 10(-4) M 5-hydroxydecanoic acid caused significant reduction of supernatant-mediated inhibitory responses. Simultaneous treatment with 10(-3) M L-arginine and 3 x 10(-5) M L-NAME significantly lessened L-NAME-induced inhibition of the supernatant-mediated response, suggesting that endogenous nitric oxide (NO) plays important roles in supernatant-mediated inhibitory responses. Chemical treatment dialyzed substances of B16-BL6 cells may release nonpeptide substance(s) of <1,000 MW, resulting in significant cessation of lymphatic pump activity via production and release of endogenous NO and activation of mitochondrial ATP-sensitive K(+) channels.

  18. Fasting in Ramadan with an insulin pump.

    Science.gov (United States)

    Kesavadev, Jothydev

    2015-05-01

    A good majority of subjects with diabetes on insulin therapies observe fasting during Ramadan. The challenge for the physician and the patient is to manage diabetes without an interruption to fasting by avoiding hypoglycaemia and simultaneously ensuring that blood glucose remain at acceptable safe levels. Insulin Pumps differ from syringes and insulin pens in that it offers a variable basal rate, different type of boluses and associated calculators. The technological advances that pumps offer, help educated subjects pre-programme a reduced basal rate throughout the day. Pumps ensure avoidance of hypoglycaemia and hyperglycaemia and preserve quality of life and enhance confidence in patients during fasting. Due to multiple benefits, insulin pumps are considered the best delivery systems for insulin during the holy month of Ramadan, despite the prerequisites for its optimal output and cost concerns.

  19. Determination of pump flow rate during cardiopulmonary bypass in obese patients avoiding hemodilution.

    Science.gov (United States)

    Santambrogio, Luisa; Leva, Cristian; Musazzi, Giorgio; Bruno, Piergiorgio; Vailati, Andrea; Zecchillo, Franco; Di Credico, Germano

    2009-01-01

    During cardiopulmonary bypass the pump flow is usually set on 2.4 L/min/m(2) of body surface area (BSA) to guarantee adequate tissue perfusion without differences for patient constitutional type. The present study attempts to evaluate the adequacy of pump flow rate in obese patients, considering the ideal weight instead of the real one, avoiding the overflow side effects and hemodilution. Obese patients with body mass index (BMI) > 30 presented for cardiac surgery were randomized in two groups: in one the cardiopulmonary bypass was led traditionally, in the other, pump flow rate was calculated on ideal BMI of 25. Demographics, preoperative tests, and monitoring data were registered. Mortality at hospital discharge and 30 days after were analyzed. The pump flow rate between the groups was different (4.46 vs. 4.87; p = 0.004); there were no differences in organ perfusion (SvO(2); diuresis) and mortality, but the study group presented fewer complications and blood transfusions. The BSA is widely used as the biometric unit to normalize physiologic parameters included pump flow rate, but it is disputable if this practice is correct also in obese patients. The study group, in which pump flow rate was set on ideal BSA, presented no difference in diuresis and mixed venous saturation but fewer complications and fewer perioperative blood transfusions.

  20. Rate equation modelling of the optically pumped spin-exchange source

    International Nuclear Information System (INIS)

    Stenger, J.; Rith, K.

    1995-01-01

    Sources for spin polarized hydrogen or deuterium, polarized via spin-exchange of a laser optically pumped alkali metal, can be modelled by rate equations. The rate equations for this type of source, operated either with hydrogen or deuterium, are given explicitly with the intention of providing a useful tool for further source optimization and understanding. Laser optical pumping of alkali metal, spin-exchange collisions of hydrogen or deuterium atoms with each other and with alkali metal atoms are included, as well as depolarization due to flow and wall collisions. (orig.)

  1. Altered Na+ transport after an intracellular alpha-subunit deletion reveals strict external sequential release of Na+ from the Na/K pump.

    Science.gov (United States)

    Yaragatupalli, Siddhartha; Olivera, J Fernando; Gatto, Craig; Artigas, Pablo

    2009-09-08

    The Na/K pump actively exports 3 Na(+) in exchange for 2 K(+) across the plasmalemma of animal cells. As in other P-type ATPases, pump function is more effective when the relative affinity for transported ions is altered as the ion binding sites alternate between opposite sides of the membrane. Deletion of the five C-terminal residues from the alpha-subunit diminishes internal Na(+) (Na(i)(+)) affinity approximately 25-fold [Morth et al. (2007) Nature 450:1043-1049]. Because external Na(+) (Na(o)(+)) binding is voltage-dependent, we studied the reactions involving this process by using two-electrode and inside-out patch voltage clamp in normal and truncated (DeltaKESYY) Xenopus-alpha1 pumps expressed in oocytes. We observed that DeltaKESYY (i) decreased both Na(o)(+) and Na(i)(+) apparent affinities in the absence of K(o)(+), and (ii) did not affect apparent Na(o)(+) affinity at high K(o)(+). These results support a model of strict sequential external release of Na(+) ions, where the Na(+)-exclusive site releases Na(+) before the sites shared with K(+) and the DeltaKESYY deletion only reduces Na(o)(+) affinity at the shared sites. Moreover, at nonsaturating K(o)(+), DeltaKESYY induced an inward flow of Na(+) through Na/K pumps at negative potentials. Guanidinium(+) can also permeate truncated pumps, whereas N-methyl-D-glucamine cannot. Because guanidinium(o)(+) can also traverse normal Na/K pumps in the absence of both Na(o)(+) and K(o)(+) and can also inhibit Na/K pump currents in a Na(+)-like voltage-dependent manner, we conclude that the normal pathway transited by the first externally released Na(+) is large enough to accommodate guanidinium(+).

  2. Pump Coastdown with the Submerged Flywheel

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyun-Gi; Seo, KyoungWoo; Kim, Seong Hoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Many research reactors are generally designed as open pool types in consideration of the heat removal of the nuclear fuels, reactor operation and accessibility. Reactor structure assembly is generally placed at the pool bottom as shown in Fig. 1. Primary cooling system pump circulates the coolant from the reactor structure to the heat exchanger in order to continuously remove the heat generated from the reactor core in the research reactor as shown in Fig. 1. The secondary cooling system releases the transferred heat to the atmosphere by the cooling tower. Coastdown flow rate of the primary cooling system pump with the submerged flywheel are calculated analytically in case of the accident situation. Coastdown flow rate is maintained until almost 80 sec when the pump stops normally. But, coastdown flow rate is rapidly decreased when the flywheel is submerged because of the friction load on the flywheel surface.

  3. Effects of atmospheric pressure conditions on flow rate of an elastomeric infusion pump.

    Science.gov (United States)

    Wang, Jong; Moeller, Anna; Ding, Yuanpang Samuel

    2012-04-01

    The effects of pressure conditions, both hyperbaric and hypobaric, on the flow rate of an elastomeric infusion pump were investigated. The altered pressure conditions were tested with the restrictor outlet at two different conditions: (1) at the same pressure condition as the Infusor elastomeric balloon and (2) with the outlet exposed to ambient conditions. Five different pressure conditions were tested. These included ambient pressure (98-101 kilopascals [kPa]) and test pressures controlled to be 10 or 20 kPa below or 75 or 150 kPa above the ambient pressure. A theoretical calculation based on the principles of fluid mechanics was also used to predict the pump's flow rate at various ambient conditions. The conditions in which the Infusor elastomeric pump and restrictor outlet were at the same pressure gave rise to average flow rates within the ±10% tolerance of the calculated target flow rate of 11 mL/hr. The flow rate of the Infusor pump decreased when the pressure conditions changed from hypobaric to ambient. The flow rate increased when the pressure conditions changed from hyperbaric to ambient. The flow rate of the Infusor elastomeric pump was not affected when the balloon reservoir and restrictor outlet were at the same pressure. The flow rate varied from 58.54% to 377.04% of the labeled flow rate when the pressure applied to the reservoir varied from 20 kPa below to 150 kPa above the pressure applied to the restrictor outlet, respectively. The maximum difference between observed flow rates and those calculated by applying fluid mechanics was 4.9%.

  4. Dam pre-release as an important operation strategy in reducing flood impact in Malaysia

    Science.gov (United States)

    Hidayah Ishak, Nurul; Mustafa Hashim, Ahmad

    2018-03-01

    The 2014 flood was reported to be one of the worst natural disaster has ever affected several states in the northern part of Peninsular Malaysia. Overwhelming rainfall was noted as one of the main factors causing such impact, which was claimed to be unprecedented to some extent. The state of Perak, which is blessed with four cascading dams had also experienced flood damage at a scale that was considered the worst in history. The rainfall received had caused the dam to reach danger level that necessitated additional discharge to be released. Safety of the dams was of great importance and such unavoidable additional discharge was allowed to avoid catastrophic failure of the dam structures. This paper discusses the dam pre-release as a significant dam management strategy in reducing flood impact. An important balance between required dam storage to be maintained and the risk element that can be afforded is the crucial factor in such enhanced operation strategy. While further possibility in developing a carefully engineered dam pre-release strategy can be explored for dam operation in Malaysia, this has already been introduced in some developed countries. Australia and South Africa are examples where pre-release has been practiced and proven to reduce flood risk. The concept involves controlling the dam lake level throughout the year, in reference to the rainfall data and the hydrological properties for the catchment area of the dams. Plentiful data analysis need to be done in contemplation of producing the optimal pre-release model. The amount of heavy rainfalls received is beyond human control but the distribution of the discharge from the dams can be further managed with the appropriate pre-release strategy.

  5. Heat release rate of wood-plastic composites

    Science.gov (United States)

    N. M. Stark; R. H. White; C. M. Clemons

    1997-01-01

    Wood-plastic composites are becoming more important as a material that fulfills recycling needs. In this study, fire performance tests were conducted on several compositions of wood and plastic materials using the Ohio State University rate of heat release apparatus. Test results included five-minute average heat release rate in kW/m2 (HRR avg) and maximum heat release...

  6. Optimization of intelligent infusion pump technology to minimize vasopressor pump programming errors.

    Science.gov (United States)

    Vadiei, Nina; Shuman, Carrie A; Murthy, Manasa S; Daley, Mitchell J

    2017-08-01

    There is a lack of data evaluating the impact of hard limit implementation into intelligent infusion pump technology (IIPT). The purpose of this study was to determine if incorporation of vasopressor upper hard limits (UHL) into IIPT increases efficacy of alerts by preventing pump programming errors. Retrospective review from five hospitals within a single healthcare network between April 1, 2013 and May 31, 2014. A total of 65,680 vasopressor data entries were evaluated; 19,377 prior to hard limit implementation and 46,303 after hard limit implementation. The primary outcome was the percent of effective alerts. The secondary outcome was the proportional dose increase from the soft limit provided. A reduction in alert rate occurred after incorporation of hard limits to the IIPT drug library (pre-UHL 4.7% vs. post-UHL 4.0%) with a subsequent increase in the number of errors prevented as represented by a higher effective alert rate (pre-UHL 23.0% vs. post-UHL 37.3%; p < 0.001). The proportional dose increase was significantly reduced (pre-UHL 188% ± 380%] vs. post-UHL 95% ± 128%; p < 0.001). Incorporation of UHLs into IIPT in a multi-site health system with varying intensive care unit and emergency department acuity increases alert effectiveness, reduces dosing errors, and reduces the magnitude of dosing errors that reach the patient.

  7. Sodium flow rate measurement method of annular linear induction pump

    International Nuclear Information System (INIS)

    Araseki, Hideo

    2011-01-01

    This report describes a method for measuring sodium flow rate of annular linear induction pumps arranged in parallel and its verification result obtained through an experiment and a numerical analysis. In the method, the leaked magnetic field is measured with measuring coils at the stator end on the outlet side and is correlated with the sodium flow rate. The experimental data and the numerical result indicate that the leaked magnetic field at the stator edge keeps almost constant when the sodium flow rate changes and that the leaked magnetic field change arising from the flow rate change is small compared with the overall leaked magnetic field. It is shown that the correlation between the leaked magnetic field and the sodium flow rate is almost linear due to this feature of the leaked magnetic field, which indicates the applicability of the method to small-scale annular linear induction pumps. (author)

  8. Accidents and Incidents Related to Intravenous Drug Administration: A Pre-Post Study Following Implementation of Smart Pumps in a Teaching Hospital.

    Science.gov (United States)

    Guérin, Aurélie; Tourel, Julien; Delage, Emmanuelle; Duval, Stéphanie; David, Marie-Johanne; Lebel, Denis; Bussières, Jean-François

    2015-08-01

    Smart pumps are expected to prevent and reduce medication errors. The implementation of smart pumps requires a significant effort and collaboration of physicians, nurses, pharmacists, and other stakeholders. The main objective of this study was to evaluate the impact of new smart pumps on reported drug-related accidents and incidents (AIs). This is a descriptive retrospective pre-post study conducted at a women's and pediatric hospital with 500 beds. A strong multidisciplinary team (nurse, pharmacist, pharmacy resident, physician, biomedical technician, information technology technician, patient safety officer, manager) was involved in the planning, implementation, and monitoring technology implementation. A total of 1045 smart pumps were implemented in 2011 in our hospital. The reported number of AIs related to intravenous drug administration (AIIV) before and after the implementation of 1045 smart pumps were collected. A total of 2911 AI events related to medications, devices, and equipment were self-reported by clinical staff in the pre-phase (Y0), 3523 in the post-phase (Y1), and 2788 in the post-phase (Y2). The total AIIV increased from 1432 in Y0 to 1834 in Y1 and decreased to 1389 in Y2. We observed no risk reduction associated with the implementation of smart pumps in a 500 bed mother-child hospital. Further studies are required to explore the details of the potential risk reduction associated with the use of smart pumps.

  9. Monitoring of pre-release cracks in prestressed concrete using fiber optic sensors

    Science.gov (United States)

    Abdel-Jaber, Hiba; Glisic, Branko

    2015-04-01

    Prestressed concrete experiences low to no tensile stresses, which results in limiting the occurrence of cracks in prestressed concrete structures. However, the nature of construction of these structures requires the concrete not to be subjected to the compressive force from the prestressing tendons until after it has gained sufficient compressive strength. Although the structure is not subjected to any dead or live load during this period, it is influenced by shrinkage and thermal variations. Thus, the concrete can experience tensile stresses before the required compressive strength has been attained, which can result in the occurrence of "pre-release" cracks. Such cracks are visually closed after the transfer of the prestressing force. However, structural capacity and behavior can be impacted if cracks are not sufficiently closed. This paper researches a method for the verification of the status of pre-release cracks after transfer of the prestressing force, and it is oriented towards achievement of Level IV Structural Health Monitoring (SHM). The method relies on measurements from parallel long-gauge fiber optic sensors embedded in the concrete prior to pouring. The same sensor network is used for the detection and characterization of cracks, as well as the monitoring of the prestressing force transfer and the determination of the extent of closure of pre-release cracks. This paper outlines the researched method and presents its application to a real-life structure, the southeast leg of Streicker Bridge on the Princeton University campus. The application structure is a curved continuous girder that was constructed in 2009. Its deck experienced four pre-release cracks that were closed beyond the critical limits based on the results of this study.

  10. Pre-steady-state kinetic analysis of 1-deoxy-D-xylulose-5-phosphate reductoisomerase from Mycobacterium tuberculosis reveals partially rate-limiting product release by parallel pathways.

    Science.gov (United States)

    Liu, Juan; Murkin, Andrew S

    2012-07-03

    As part of the non-mevalonate pathway for the biosynthesis of the isoprenoid precursor isopentenyl pyrophosphate, 1-deoxy-D-xylulose-5-phosphate (DXP) reductoisomerase (DXR) catalyzes the conversion of DXP into 2-C-methyl-D-erythritol 4-phosphate (MEP) by consecutive isomerization and NADPH-dependent reduction reactions. Because this pathway is essential to many infectious organisms but is absent in humans, DXR is a target for drug discovery. In an attempt to characterize its kinetic mechanism and identify rate-limiting steps, we present the first complete transient kinetic investigation of DXR. Stopped-flow fluorescence measurements with Mycobacterium tuberculosis DXR (MtDXR) revealed that NADPH and MEP bind to the free enzyme and that the two bind together to generate a nonproductive ternary complex. Unlike the Escherichia coli orthologue, MtDXR exhibited a burst in the oxidation of NADPH during pre-steady-state reactions, indicating a partially rate-limiting step follows chemistry. By monitoring NADPH fluorescence during these experiments, the transient generation of MtDXR·NADPH·MEP was observed. Global kinetic analysis supports a model involving random substrate binding and ordered release of NADP(+) followed by MEP. The partially rate-limiting release of MEP occurs via two pathways--directly from the binary complex and indirectly via the MtDXR·NADPH·MEP complex--the partitioning being dependent on NADPH concentration. Previous mechanistic studies, including kinetic isotope effects and product inhibition, are discussed in light of this kinetic mechanism.

  11. Experimental study on effects of double pumps switching on water supply flow rate

    International Nuclear Information System (INIS)

    Wang Xin; Han Weishi

    2012-01-01

    Flow characteristics in the process of switching one centrifugal pump to the other was investigated experimentally using a closed loop with two centrifugal pumps and two check valves. Characteristics of the check valves responding and the flow rate changing during the process of switching was studied by experimental data analysis. The results show that in the switching process with high and low original flow rate, the restoring time is 26 s and 21 s respectively; the lowest flow rates are 59.4% and 87.2% out of that in normal water supply, and the average deficit of feed water is 20.8% and 7.5% respectively. Compared to double-pump switching with low flow rate, a longer transition time. more intense flow fluctuations and increased water loss are observed with high flow rate, which has significantly effects on the stability of water supply. (authors)

  12. Test results of pre-production prototype distributed ion pump design for the PEP-II Asymmetric B-Factory collider

    Energy Technology Data Exchange (ETDEWEB)

    Holdener, F.R.; Behne, D.; Hathaway, D. [and others

    1995-04-24

    We have built and tested a plate-type pre-production distributed Ion Pump (DIP) for the PEP-II B-Factory High Energy Ring (HER). The design has been an earlier design to use less materials and to costs. Penning cell hole sizes of 15, 18, and 21 mm have been tested in a uniform magnetic field of 0.18 T to optimize pumping speed. The resulting final DIP design consisting of a 7-plate, 15 mm basic cell size anode was magnetic field of the HER dipole. A description of the final optimized DIP design will be presented along with the test results of the pumping speed measurements.

  13. Wall relaxation rates for an optically pumped NA vapor

    International Nuclear Information System (INIS)

    Swenson, D.R.; Anderson, L.W.

    1986-01-01

    The wall relaxation rates for an optically pumped Na vapor have been measured for a variety of wall surfaces. We find that fluorocarbon rubber (Fluorel, Viton) and organosilicones (silicone rubber, dry film) at a temperature of 250 C have respectively relaxation rates that correspond on the average to 10 to 15 and 200 to 500 bounces before depolarization occurs. 7 refs., 3 figs

  14. Diffusion rates for elevated releases

    International Nuclear Information System (INIS)

    Ramsdell, J.V.

    1983-11-01

    A search of the literature related to diffusion from elevated sources has determined that an adequate data base exists for use in developing parameterizations for estimating diffusion rates for material released from free standing stacks at nuclear power plants. A review of published data analyses indicates that a new parameterization of horizontal diffusion rates specifically for elevated releases is not likely to significantly change the magnitudes of horizontal diffusion coefficients on the average. However, the uncertainties associated with horizontal diffusion coefficient estimates under any given set of atmospheric conditions could be reduced by a new parameterization. Similarly, a new parameterization of vertical diffusion rates would be unlikely to significantly alter the magnitudes of diffusion coefficients for unstable atmospheric conditons. However, for neutral and stable atmospheric conditions, a new parameterization of vertical diffusion rates might increase vertical diffusion coefficients significantly. The increase would move ground-level time-integrated concentration maxima closer to the plant and would increase the maxima. 55 references, 2 figures, 4 tables

  15. Benefits and risks of using smart pumps to reduce medication error rates: a systematic review.

    Science.gov (United States)

    Ohashi, Kumiko; Dalleur, Olivia; Dykes, Patricia C; Bates, David W

    2014-12-01

    Smart infusion pumps have been introduced to prevent medication errors and have been widely adopted nationally in the USA, though they are not always used in Europe or other regions. Despite widespread usage of smart pumps, intravenous medication errors have not been fully eliminated. Through a systematic review of recent studies and reports regarding smart pump implementation and use, we aimed to identify the impact of smart pumps on error reduction and on the complex process of medication administration, and strategies to maximize the benefits of smart pumps. The medical literature related to the effects of smart pumps for improving patient safety was searched in PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) (2000-2014) and relevant papers were selected by two researchers. After the literature search, 231 papers were identified and the full texts of 138 articles were assessed for eligibility. Of these, 22 were included after removal of papers that did not meet the inclusion criteria. We assessed both the benefits and negative effects of smart pumps from these studies. One of the benefits of using smart pumps was intercepting errors such as the wrong rate, wrong dose, and pump setting errors. Other benefits include reduction of adverse drug event rates, practice improvements, and cost effectiveness. Meanwhile, the current issues or negative effects related to using smart pumps were lower compliance rates of using smart pumps, the overriding of soft alerts, non-intercepted errors, or the possibility of using the wrong drug library. The literature suggests that smart pumps reduce but do not eliminate programming errors. Although the hard limits of a drug library play a main role in intercepting medication errors, soft limits were still not as effective as hard limits because of high override rates. Compliance in using smart pumps is key towards effectively preventing errors. Opportunities for improvement include upgrading drug

  16. Solid state pump lasers with high power and high repetition rate

    International Nuclear Information System (INIS)

    Oba, Masaki; Kato, Masaaki; Arisawa, Takashi

    1995-01-01

    We built a laser diode pumped solid state green laser (LDPSSGL) rated at high repetition rate. Two laser heads are placed in one cavity with a rotator in between to design to avoid thermal lensing and thermal birefringence effect. Although average green laser power higher than 10 W was obtained at 1 kHz repetition rate with pulse width of 20-30 nsec, the beam quality was so much deteriorated that energy efficiency was as low as 2 %. Learning from this experience that high power oscillator causes a lot of thermal distortion not only in the laser rod but also in the Q-switch device, we proceeded to built a oscillator/amplifier system. A low power oscillator has a slab type crystal in the cavity. As a result spatial distribution of laser power was extremely improved. As we expect that the high repetition rate solid state laser should be CW operated Q-switch type laser from the view point of lifetime of diode lasers, a conventional arc lamp pumped CW Q-switch green YAG laser of which the repetition rate is changeable from 1 kHz to 5 kHz and the pulse width is 250-570 nsec was also tested to obtain pumping characteristics of a dye laser as a function of power, pulse width etc., and dye laser pulse width of 100-130 nsec were obtained. (author)

  17. Relationship among reaction rate, release rate and efficiency of nanomachine-based targeted drug delivery.

    Science.gov (United States)

    Zhao, Qingying; Li, Min; Luo, Jun

    2017-12-04

    In nanomachine applications towards targeted drug delivery, drug molecules released by nanomachines propagate and chemically react with tumor cells in aqueous environment. If the nanomachines release drug molecules faster than the tumor cells react, it will result in loss and waste of drug molecules. It is a potential issue associated with the relationship among reaction rate, release rate and efficiency. This paper aims to investigate the relationship among reaction rate, release rate and efficiency based on two drug reception models. We expect to pave a way for designing a control method of drug release. We adopted two analytical methods that one is drug reception process based on collision with tumors and another is based on Michaelis Menten enzymatic kinetics. To evaluate the analytical formulations, we used the well-known simulation framework N3Sim to establish simulations. The analytical results of the relationship among reaction rate, release rate and efficiency is obtained, which match well with the numerical simulation results in a 3-D environment. Based upon two drug reception models, the results of this paper would be beneficial for designing a control method of nanomahine-based drug release.

  18. SHAKER Version 0.0/5 Pre-release Notes

    CERN Document Server

    CERN. Geneva

    1993-01-01

    SHAKER V0.0/5 is a pre-release of a simple cocktail central rapidity phase space event generator developed for the simulation of LHC Heavy Ion events. A modified version of JETSET 7.3 (the / LUJETS / common has been enlarged to 50000 particles and the LUEDIT routine has been modified to rearrange the particle weights vectors when called with MEDIT=1) is used to manage the events. All event information is included in / LUJETS / according to Lund conventions [1].

  19. Estimation of daily flow rate of photovoltaic water pumping systems using solar radiation data

    Directory of Open Access Journals (Sweden)

    M. Benghanem

    2018-03-01

    Full Text Available This paper presents a simple model which allows us to contribute in the studies of photovoltaic (PV water pumping systems sizing. The nonlinear relation between water flow rate and solar power has been obtained experimentally in a first step and then used for performance prediction. The model proposed enables us to simulate the water flow rate using solar radiation data for different heads (50 m, 60 m, 70 m and 80 m and for 8S × 3P PV array configuration. The experimental data are obtained with our pumping test facility located at Madinah site (Saudi Arabia. The performances are calculated using the measured solar radiation data of different locations in Saudi Arabia. Knowing the solar radiation data, we have estimated with a good precision the water flow rate Q in five locations (Al-Jouf, Solar Village, AL-Ahsa, Madinah and Gizan in Saudi Arabia. The flow rate Q increases with the increase of pump power for different heads following the nonlinear model proposed. Keywords: Photovoltaic water pumping system, Solar radiation data, Simulation, Flow rate

  20. Insulin appearance of subcutaneously infused insulin: influence of the basal rate pulse interval of the infusion pump.

    Science.gov (United States)

    Birch, K; Hildebrandt, P; Jensen, B M; Kühl, C; Brange, J

    1985-05-01

    To compare the metabolic control and the pharmacokinetics of infused insulin using an insulin pump (Auto-Syringe AS 6C) which provides the basal rate in pulses every 2-10 min with a pump (Medix Syringe Driver 209) providing the basal rate in pulses every 15-60 min, 6 C-peptide negative diabetic patients received, in random order, identical, but individual, insulin treatment during one 4-day period using the Auto-Syringe pump and another 4-day period using the Medix pump. On the fourth day of each period, blood glucose and plasma-free insulin were estimated every 30 min for 7 hr and every 5 min for the next hour. Plasma-free insulin was significantly higher on 3 time points out of the 26 possible when using the Medix pump, but this was not reflected in the blood glucose concentrations which were similar in the 2 periods. The results indicate that, from a metabolic and pharmacokinetic point of view, insulin pumps working with larger intervals between the basal rate pulses are just as good as the more technically advanced and hence often more expensive pumps which provide the basal rate in more and smaller pulses.

  1. Rapid photolytic release of adenosine 5'-triphosphate from a protected analogue: utilization by the Na:K pump of human red blood cell ghosts

    International Nuclear Information System (INIS)

    Kaplan, J.H.; Forbush, B. III; Hoffman, J.F.

    1978-01-01

    2-Nitrobenzyl phosphate and 1-(2-nitro)phenylethyl phosphate have been synthesized and demonstrated to be suitable as photolabile sources of inorganic phosphate. The same protecting groups were attached to the terminal phosphate of adenosine 5'-triphosphate. These caged ATP compounds released adenosine 5'-triphosphate on illumination at 340 nm in aqueous solution and P 3 -1-(2-nitro)phenylethyl-ATP gave about a 70 percent yield in under 30 s. The unphotolyzed caged ATP was neither a substrate nor inhibitor of purified renal Na,K-ATPase (EC 3.61.3). Following photolysis in the presence of the enzyme, the liberated ATP was hydrolyzed but at an inhibited rate. The photo-dependent inhibition could be eliminated by prior addition of glutathione or bisulfite to the irradiated solution. Caged ATP was incorporated into resealed human erythrocyte ghosts prepared from red blood cells depleted of internal energy stores. While the NA : K pump was unable to use incorporated caged ATP as a substrate, the ATP liberated by photolysis activated the pump as evidenced by measurements of K-dependent, ouabain-sensitive Na efflux. Thus the caged ATP can be used as a stable source of ATP unmetabolizable by intracellular ATPases until the ATP is released following photolytic irradiation

  2. A Web Based Framework for Pre-release Testing of Mobile Applications

    Directory of Open Access Journals (Sweden)

    Hamdy Abeer

    2016-01-01

    Full Text Available Mobile applications are becoming an integral part of daily life and of business’s marketing plan. They are helpful in promoting for the business, attracting and retaining customers. Software testing is vital to ensure the delivery of high quality mobile applications that could be accessed across different platforms and meet business and technical requirements. This paper proposes a web based tool, namely Pons, for the distribution of pre-release mobile applications for the purpose of manual testing. Pons facilities building, running, and manually testing Android applications directly in the browser. It gets the developers and end users engaged in testing the applications in one place, alleviates the tester’s burden of installing and maintaining testing environments, and provides a platform for developers to rapidly iterate on the software and integrate changes over time. Thus, it speeds up the pre-release testing process, reduces its cost and increases customer satisfaction.

  3. Evaluating an approach to improving the adoption rate of wireless drug library updates for smart pumps.

    Science.gov (United States)

    Poppe, Lindsey B; Eckel, Stephen F

    2011-01-15

    An academic medical center's approach to improving the adoption rate of wireless drug library updates for smart pumps was evaluated. A multidisciplinary team composed of pharmacy, nursing, medical engineering, materials management, and patient equipment personnel at an academic medical center collaborated to update the drug libraries of more than 1800 smart pumps via a wireless control system. Two pilot tests were completed to identify and resolve issues before the live wireless update was attempted. The second pilot test, a passive approach, produced an adoption rate of 42% of 1804 pumps at the end of one week and a rate of 56% on day 10. The goal of 80% was not achieved until day 22. The change to an active multidisciplinary process three months later produced an adoption rate of 80% for 1869 pumps on day 10, resulting in a 45.4% increase in the adoption rate between the two trials on day 10 (p libraries reduced the amount of time required to reach a goal adoption rate of 80%.

  4. Measurement of the electron quenching rate in an electron beam pumped KrF* laser

    International Nuclear Information System (INIS)

    Nishioka, Hajime; Kurashima, Toshio; Kuranishi, Hideaki; Ueda, Kenichi; Takuma, Hiroshi; Sasaki, Akira; Kasuya, Koichi.

    1988-01-01

    The electron quenching rate of KrF * in an electron beam pumped laser has been studied by accurately measuring the saturation intensity in a mixture of Ar/Kr/F 2 = 94/6/0.284. The input intensity of the measurements was widely varied from 100 W cm -2 (small signal region) to 100 MW cm -2 (absorption dominant region) in order to separate laser parameters which are small signal gain coefficient, absorption coefficient, and saturation intensity from the measured net gain coefficients. The gas pressure and the pump rate were varied in the range of 0.5 to 2.5 atm and 0.3 to 1.4 MW cm -3 , respectively. The electron quenching rate constant of 4.5 x 10 -7 cm 3 s -1 was obtained from the pressure and the pump rate dependence of the KrF * saturation intensity with the temperature dependence of the rate gas 3-body quenching rate as a function of gas temperature to the -3rd power. The small signal gain coefficients calculated with the determined quenching rate constants shows excellent agreement with the measurements. (author)

  5. Nano-suspension coating as a technique to modulate the drug release from controlled porosity osmotic pumps for a soluble agent.

    Science.gov (United States)

    Bahari, Leila Azharshekoufeh; Javadzadeh, Yousef; Jalali, Mohammad Barzegar; Johari, Peyvand; Nokhodchi, Ali; Shokri, Javad

    2017-05-01

    In controlled porosity osmotic pumps (CPOP), usually finding a single solvent with a capability to dissolve both film former (hydrophobic) and pore former (hydrophilic) is extremely challenging. Therefore, the aim of the present investigation was to tackle the issue associated with controlled porosity osmotic pump (CPOP) system using nano-suspension coating method. In the present study 4-Amino pyridine was used as a highly water soluble drug. In this method, a hydrophilic pore former (sucrose or mannitol) in nano range was suspended in polymeric coating solution using ball-mill. The performance of the prepared formulations was assessed in terms of D 12h (cumulative release percent after 12h), Dev zero (mean percent deviation of drug release from zero order kinetic), t L (lag time of the drug release) and RSQ zero . The results revealed that gelling agent amount (HPMC E 15LV ) in core and pore former concentration in SPM had crucial effect on SPM integrity. All the optimised formulations showed a burst drug release due to fast dissolving nature of the pore formers. Results obtained from scanning electron microscopy demonstrated the formation of nanopores in the membrane where the drug release takes place via these nanopores. Nano suspension coating method can be introduced as novel method in formulation of CPOPs. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Estimation of daily flow rate of photovoltaic water pumping systems using solar radiation data

    Science.gov (United States)

    Benghanem, M.; Daffallah, K. O.; Almohammedi, A.

    2018-03-01

    This paper presents a simple model which allows us to contribute in the studies of photovoltaic (PV) water pumping systems sizing. The nonlinear relation between water flow rate and solar power has been obtained experimentally in a first step and then used for performance prediction. The model proposed enables us to simulate the water flow rate using solar radiation data for different heads (50 m, 60 m, 70 m and 80 m) and for 8S × 3P PV array configuration. The experimental data are obtained with our pumping test facility located at Madinah site (Saudi Arabia). The performances are calculated using the measured solar radiation data of different locations in Saudi Arabia. Knowing the solar radiation data, we have estimated with a good precision the water flow rate Q in five locations (Al-Jouf, Solar Village, AL-Ahsa, Madinah and Gizan) in Saudi Arabia. The flow rate Q increases with the increase of pump power for different heads following the nonlinear model proposed.

  7. Research of heat releasing element of an active zone of gaseous nuclear reactor with pumped through nuclear fuel - uranium hexafluoride (UF6)

    International Nuclear Information System (INIS)

    Batyrbekov, G.; Batyrbekov, E.; Belyakova, E.; Kunakov, S.; Koltyshev, S.

    1996-01-01

    The purpose of the offered project is learning physics and substantiation of possibility of creation gaseous nuclear reactor with pumped through nuclear fuel-hexafluoride of uranium (Uf6).Main problems of this work are'. Determination of physic-chemical, spectral and optical properties of non-equilibrium nuclear - excited plasma of hexafluoride of uranium and its mixtures with other gases. Research of gas dynamics of laminar, non-mixing two-layer current of gases of hexafluoride of uranium and helium at availability and absence of internal energy release in hexafluoride of uranium with the purpose to determinate a possibility of isolation of hexafluoride of uranium from walls by inert helium. Creation and research of gaseous heat releasing element with pumped through fuel Uf6 in an active zone of research nuclear WWR-K reactor. Objects of a research: Non-equilibrium nuclear - excited plasma of hexafluoride of uranium and its mixtures with other gases. With use of specially created ampoules will come true in-reactor probe and spectral diagnostics of plasma. Calculations of kinetics with the account of main elementary processes proceeding in it, will be carried out. Two-layer non-mixed streams of hexafluoride of uranium and helium at availability and absence of internal energy release. Conditions of obtaining and characteristics of such streams will be investigated. Gaseous heat releasing element with pumped through fuel - Uf6 in an active zone of nuclear WWR-K reactor

  8. Numerical modelling of groundwater flow to understand the impacts of pumping on arsenic migration in the aquifer of North Bengal Plain

    Science.gov (United States)

    Sikdar, P. K.; Chakraborty, Surajit

    2017-03-01

    In this paper, numerical simulations of regional-scale groundwater flow of North Bengal Plain have been carried out with special emphasis on the arsenic (As)-rich alluvium filled gap between the Rajmahal hills on the west and the Garo hills on the east. The proposed concern of this modelling arose from development that has led to large water table declines in the urban area of English Bazar block, Malda district, West Bengal and possible transport of As in the near future from the adjacent As-polluted aquifer. Groundwater occurs under unconfined condition in a thick zone of saturation within the Quaternary alluvial sediments. Modelling indicates that current pumping has significantly changed the groundwater flowpaths from pre-development condition. At the present pumping rate, the pumping wells of the urban area may remain uncontaminated till the next 25 yrs, considering only pure advection of water but some water from the As-polluted zone may enter wells by 50 yrs. But geochemical and other processes such as adsorption, precipitation, redox reaction and microbial activity may significantly retard the predicted rate by advective transport. In the rural areas, majority of the water pumped from the aquifer is for irrigation, which is continuously re-applied on the surface. The near-vertical nature of the flowpaths indicates that, where As is present or released at shallow depths, it will continue to occur in pumping wells. Modelling also indicates that placing all the pumping wells at depths below 100 m may not provide As-free water permanently.

  9. High-energy, high-repetition-rate picosecond pulses from a quasi-CW diode-pumped Nd:YAG system.

    Science.gov (United States)

    Noom, Daniel W E; Witte, Stefan; Morgenweg, Jonas; Altmann, Robert K; Eikema, Kjeld S E

    2013-08-15

    We report on a high-power quasi-CW pumped Nd:YAG laser system, producing 130 mJ, 64 ps pulses at 1064 nm wavelength with a repetition rate of 300 Hz. Pulses from a Nd:YVO(4) oscillator are first amplified by a regenerative amplifier to the millijoule level and then further amplified in quasi-CW diode-pumped Nd:YAG modules. Pulsed diode pumping enables a high gain at repetition rates of several hundred hertz, while keeping thermal effects manageable. Birefringence compensation and multiple thermal-lensing-compensated relay-imaging stages are used to maintain a top-hat beam profile. After frequency doubling, 75 mJ pulses are obtained at 532 nm. The intensity stability is better than 1.1%, which makes this laser an attractive pump source for a high-repetition-rate optical parametric amplification system.

  10. Future directions in 980-nm pump lasers: submarine deployment to low-cost watt-class terrestrial pumps

    Science.gov (United States)

    Gulgazov, Vadim N.; Jackson, Gordon S.; Lascola, Kevin M.; Major, Jo S.; Parke, Ross; Richard, Tim; Rossin, Victor V.; Zhang, Kai

    1999-09-01

    The demands of global bandwidth and distribution are rising rapidly as Internet usage grows. This fundamentally means that more photons are flowing within optical cables. While transmitting sources launches some optical power, the majority of the optical power that is present within modern telecommunication systems originates from optical amplifiers. In addition, modern optical amplifiers offer flat optical gain over broad wavelength bands, thus making possible dense wavelength de-multiplexing (DWDM) systems. Optical amplifier performance, and by extension the performance of the laser pumps that drive them, is central to the future growth of both optical transmission and distribution systems. Erbium-doped amplifiers currently dominate optical amplifier usage. These amplifiers absorb pump light at 980 nm and/or 1480 nm, and achieve gain at wavelengths around 1550 nm. 980 nm pumps achieve better noise figures and are therefore used for the amplification of small signals. Due to the quantum defect, 1480 nm lasers deliver more signal photon per incident photon. In addition, 1480 nm lasers are less expensive than 980 nm lasers. Thus, 1480 nm pump lasers are used for amplification in situations where noise is not critical. The combination of these traits leads to the situation where many amplifiers contain 980 nm lasers to pump the input section of the Er- doped fiber with 1480 nm lasers being used to pump the latter section of Er fiber. This can be thought of as using 980 nm lasers to power an optical pre-amplifier with the power amplification function being pump with 1480 nm radiation. This paper will focus on 980 nm pump lasers and the impact that advances in 980 nm pump technology will have on optical amplification systems. Currently, 980 nm technology is rapidly advancing in two areas, power and reliability. Improving reliability is becoming increasingly important as amplifiers move towards employing more pump lasers and using these pump lasers without redundancy

  11. Changes in Inmates’ Substance Use and Dependence From Pre-Incarceration to One Year Post-Release

    Science.gov (United States)

    Tangney, June P.; Folk, Johanna B.; Graham, David M.; Stuewig, Jeffrey B.; Blalock, Daniel V.; Salatino, Andrew; Blasko, Brandy B.; Moore, Kelly E.

    2016-01-01

    Purpose To assess changes in inmates’ misuse of substances from pre- to post-incarceration. Methods In Study 1, professionals (n = 162) and laypersons (n = 50) predicted how jail inmates’ substance misuse would change from pre-incarceration to post-release. In Study 2, a longitudinal study of 305 jail inmates, we examined actual changes in substance use and dependence from pre-incarceration to the first year post-incarceration, as well as whether changes varied as a function of demographic, criminal justice, treatment, and personality factors. Results Professionals and laypersons predicted little change in substance misuse whereas, in fact, inmates’ frequency of substance use and dependence decreased substantially from pre-incarceration to post-release. Sharper decreases were observed for inmates who were female, younger, more educated, serving longer sentences, enrolled in substance abuse treatment, high in shame-proneness, and low in criminogenic thinking. Race, first time incarceration, transfer to other correctional facilities, mandated community supervision (probation), and guilt-proneness did not predict changes in substance use or dependence. Conclusions Although substance misuse decreased, this remains a population high in need of substance abuse treatment both upon arrest and at one year post-incarceration; 60% of former inmates met at least one DSM-IV criterion for substance dependence at one year post-release. PMID:27458324

  12. Study of Hydrogen Pumping through Condensed Argon in Cryogenic pump

    International Nuclear Information System (INIS)

    Jadeja, K A; Bhatt, S B

    2012-01-01

    In ultra high vacuum (UHV) range, hydrogen is a dominant residual gas in vacuum chamber. Hydrogen, being light gas, pumping of hydrogen in this vacuum range is limited with widely used UHV pumps, viz. turbo molecular pump and cryogenic pump. Pre condensed argon layers in cryogenic pump create porous structure on the surface of the pump, which traps hydrogen gas at a temperature less than 20° K. Additional argon gas injection in the cryogenic pump, at lowest temperature, generates multiple layers of condensed argon as a porous frost with 10 to 100 A° diameters pores, which increase the pumping capacity of hydrogen gas. This pumping mechanism of hydrogen is more effective, to pump more hydrogen gas in UHV range applicable in accelerator, space simulation etc. and where hydrogen is used as fuel gas like tokamak. For this experiment, the cryogenic pump with a closed loop refrigerator using helium gas is used to produce the minimum cryogenic temperature as ∼ 14° K. In this paper, effect of cryosorption of hydrogen is presented with different levels of argon gas and hydrogen gas in cryogenic pump chamber.

  13. The surface-forming energy release rate versus the local energy release rate

    OpenAIRE

    Xiao, Si; Wang, He-ling; Landis, Chad M; Hwang, Keh-Chih; Liu, Bin

    2016-01-01

    This paper identifies two ways to extract the energy (or power) flowing into a crack tip during propagation based on the power balance of areas enclosed by a stationary contour and a comoving contour. It is very interesting to find a contradiction that two corresponding energy release rates (ERRs), a surface-forming ERR and a local ERR, are different when stress singularity exists at a crack tip. Besides a rigorous mathematical interpretation, we deduce that the stress singularity leads to an...

  14. Controlled porosity solubility modulated osmotic pump tablets of gliclazide.

    Science.gov (United States)

    Banerjee, Arti; Verma, P R P; Gore, Subhash

    2015-06-01

    A system that can deliver drug at a controlled rate is very important for the treatment of various chronic diseases such as diabetes, asthma, and heart disease. Poorly water-soluble drug with pH-dependent solubility such as gliclazide (GLZ) offers challenges in the controlled-release formulation because of low dissolution rate and poor bioavailability. Solid dispersion (SD) of GLZ consisted of hydroxypropyl cellulose (HPC-SSL) as a polymeric solubilizer was manufactured by hot melt extrusion (HME) technology. Then, controlled porosity osmotic pump (CPOP) tablet of gliclazide was designed to deliver drug in a controlled manner up to 16 h. The developed formulation was optimized for type and level of pore former and coating weight gain. The optimized formulation was found to exhibit zero order kinetics independent of pH and agitation speed but depends on osmotic pressure of dissolution media indicated that mechanism of drug release was osmotic pressure. The in vivo performance prediction of developed formulation using convolution approach revealed that the developed formulation was superior to the existing marketed extended-release formulation in terms of attaining steady state plasma levels and indicated adequate exposure in translating hypoglycemic response. The prototype solubilization method combined with controlled porosity osmotic pump based technique could provide a unique way to increase dissolution rate and bioavailability of many poorly water-soluble, narrow therapeutic index drugs used in diabetes, cardiovascular diseases, etc.

  15. Influence of ceramic dental crown coating substrate thickness ratio on strain energy release rate

    Science.gov (United States)

    Khasnulhadi, K.; Daud, R.; Mat, F.; Noor, S. N. F. M.; Basaruddin, K. S.; Sulaiman, M. H.

    2017-10-01

    This paper presents the analysis of coating substrate thickness ratio effect on the crown coating fracture behaviour. The bi-layer material is examined under four point bending with pre-crack at the bottom of the core material by using finite element. Three different coating thickness of core/substrate was tested which is 1:1, 1:2 and 2:1. The fracture parameters are analysed based on bilayer and homogenous elastic interaction. The result shows that the ratio thickness of core/veneer provided a significant effect on energy release rate.

  16. Release rates from waste packages in a salt repository

    International Nuclear Information System (INIS)

    Chambre, P.L.; Hwang, Y.; Lee, W.W.L.; Pigford, T.H.

    1987-06-01

    In this report we present estimates of radionuclide release rates from waste packages into salt. This conservative and bounding analysis shows that release rates from waste packages in salt are well below the US Nuclear Regulatory Commission's performance objectives for the engineered barrier system. 2 refs., 2 figs

  17. Measurement of the electron quenching rate in an electron beam pumped KrF/sup */ laser

    Energy Technology Data Exchange (ETDEWEB)

    Nishioka, Hajime; Kurashima, Toshio; Kuranishi, Hideaki; Ueda, Kenichi; Takuma, Hiroshi; Sasaki, Akira; Kasuya, Koichi.

    1988-09-01

    The electron quenching rate of KrF/sup */ in an electron beam pumped laser has been studied by accurately measuring the saturation intensity in a mixture of Ar/Kr/F/sub 2/ = 94/6/0.284. The input intensity of the measurements was widely varied from 100 W cm/sup -2/ (small signal region) to 100 MW cm/sup -2/ (absorption dominant region) in order to separate laser parameters which are small signal gain coefficient, absorption coefficient, and saturation intensity from the measured net gain coefficients. The gas pressure and the pump rate were varied in the range of 0.5 to 2.5 atm and 0.3 to 1.4 MW cm/sup -3/, respectively. The electron quenching rate constant of 4.5 x 10/sup -7/ cm/sup 3/s/sup -1/ was obtained from the pressure and the pump rate dependence of the KrF/sup */ saturation intensity with the temperature dependence of the rate gas 3-body quenching rate as a function of gas temperature to the -3rd power. The small signal gain coefficients calculated with the determined quenching rate constants shows excellent agreement with the measurements.

  18. Application of the constant rate of pressure change method to improve jet pump performance

    International Nuclear Information System (INIS)

    Long, X P; Yang, X L

    2012-01-01

    This paper adopts a new method named the constant rate of pressure change (CRPC) to improve the jet pump performance. The main contribution of this method is that the diffuser generates uniform pressure gradient. The performance of the jet pump with new diffusers designed by the CRPC method, obtained by CFD methods, was compared with that of the jet pump with traditional conical diffusers. It is found that the CRPC diffuser produces a linear pressure increase indeed. The higher friction loss and the separation decrease the CRPC diffuser efficiency and then lower the pump efficiency. The pump with shorter throats has higher efficiency at small flow ratio while its efficiency is lower than the original pump at lager flow ratio and the peak efficiency of the pumps with the throat length of 5-6 Dt is higher than that of the pumps with other throat length. When the throat length is less than 4 Dt, the CRPC diffuser efficiency is higher than the conical diffuser. The CRPC method could also be used to design the nozzle and other situations needing the pressure change gradually.

  19. Heat release rate from the combustion of uranium

    International Nuclear Information System (INIS)

    Solbrig, C.W.

    1995-01-01

    Fuel treatment is planned at the Argonne National Laboratory on EBR-II spent fuel. The electrochemical treatment process is carried out in a cell with an argon atmosphere to prevent any reaction. The amount of fuel processed at any time is limited by the amount of energy which could be released by metal combustion if air is inadvertently allowed into the cell since the heat release would increase the cell pressure. The cell pressure is required to be below atmospheric even if combustion occurs to ensure no cell gas/aerosol is released to the environment. Metal fires can release large amounts of heat. In certain configurations such as fine particulate, metal can be pyrophoric at room temperature. When the metal is a nuclear fuel, it is important to be able to predict the reaction/heat release rate if the metal is inadvertently exposed to air. A realistic combustion model is needed to predict heat release rates for the many different flow and transport configurations which exist in the various fuel processing steps. A model for the combustion of uranium is developed here which compares satisfactorily to experimental data

  20. Enzyme-Powered Pumps: From Fundamentals to Applications

    Science.gov (United States)

    Ortiz-Rivera, Isamar

    Non-mechanical nano and microfluidic devices that function without the aid of an external power source, and can be tailored to meet specific needs, represent the next generation of smart devices. Recently, we have shown that surface-bound enzymes can act as pumps driving large-scale fluid flows in the presence of any substance that triggers the enzymatic reaction (e.g. substrate, co-factor, or biomarker). The fluid velocities attained in such systems depend directly on the enzymatic reaction rate and the concentration of the substance that initiates enzymatic catalysis. The use of biochemical reactions to power a micropump offers the advantages of specificity, sensitivity, and selectively, eliminating at the same time the need of an external power source, while providing biocompatibility. More importantly, these self-powered pumps overcome a significant obstacle in nano- and micro-fluidics: the need to use external pressure-driven pumps to push fluids through devices. Certainly, the development of enzyme-powered devices opens up new venues in biochemical engineering, particularly in the biomedical field. The work highlighted in this dissertation covers all the studies performed with enzyme-powered pumps, from the development of the micropump design, to the efforts invested in understanding the enzyme pump concept as a whole. The data collected to date, aims to expand our knowledge about enzyme-powered micropumps from the inside out: not only by exploring the different applications of these devices at the macroscale, but also by investigating in depth the mechanism of pump activation behind these systems. Specifically, we have focused on: (1) The general features that characterize the pumping behavior observed in enzyme-powered pumps, as well as the optimization of the device, (2) the possible mechanisms behind fluid motion, including the role of enzyme coverage and/or activity on the transduction of chemical energy into mechanical fluid flow in these devices

  1. Design and optimization of a large flow rate booster pump in SWRO energy recovery system

    International Nuclear Information System (INIS)

    Lai, Z N; Wu, P; Wu, D Z; Wang, L Q

    2013-01-01

    Seawater reverse osmosis (SWRO) is a high energy-consumption industry, so energy efficiency is an important issue. Energy recovery systems, which contain a pressure exchanger and a booster pump, are widely used in SWRO plants. As a key part of energy recovery system, the difficulty of designing booster pumps lies in high inlet pressure, high medium causticity and large flow rate. High inlet pressure adds difficulties to seal design, and large flow rate and high efficiency requirement bring high demand for hydraulic design. In this paper, a 625 m 3 /h booster pump is designed and optimized according to the CFD (Computational Fluid Dynamics) simulation results. The impeller and volute is well designed, a new type of high pressure mechanical seal is applied and axial force is well balanced. After optimization based on blade redesign, the efficiency of the pump was improved. The best efficiency reaches more than 85% at design point according to the CFD simulation result

  2. Design and optimization of a large flow rate booster pump in SWRO energy recovery system

    Science.gov (United States)

    Lai, Z. N.; Wu, P.; Wu, D. Z.; Wang, L. Q.

    2013-12-01

    Seawater reverse osmosis (SWRO) is a high energy-consumption industry, so energy efficiency is an important issue. Energy recovery systems, which contain a pressure exchanger and a booster pump, are widely used in SWRO plants. As a key part of energy recovery system, the difficulty of designing booster pumps lies in high inlet pressure, high medium causticity and large flow rate. High inlet pressure adds difficulties to seal design, and large flow rate and high efficiency requirement bring high demand for hydraulic design. In this paper, a 625 m3/h booster pump is designed and optimized according to the CFD (Computational Fluid Dynamics) simulation results. The impeller and volute is well designed, a new type of high pressure mechanical seal is applied and axial force is well balanced. After optimization based on blade redesign, the efficiency of the pump was improved. The best efficiency reaches more than 85% at design point according to the CFD simulation result.

  3. Pumping behavior of sputter ion pumps

    International Nuclear Information System (INIS)

    Chou, T.S.; McCafferty, D.

    The ultrahigh vacuum requirements of ISABELLE is obtained by distributed pumping stations. Each pumping station consists of 1000 l/s titanium sublimation pump for active gases (N 2 , H 2 , O 2 , CO, etc.), and a 20 l/s sputter ion pump for inert gases (methane, noble gases like He, etc.). The combination of the alarming production rate of methane from titanium sublimation pumps (TSP) and the decreasing pumping speed of sputter ion pumps (SIP) in the ultrahigh vacuum region (UHV) leads us to investigate this problem. In this paper, we first describe the essential physics and chemistry of the SIP in a very clean condition, followed by a discussion of our measuring techniques. Finally measured methane, argon and helium pumping speeds are presented for three different ion pumps in the range of 10 -6 to 10 -11 Torr. The virtues of the best pump are also discussed

  4. Determination of the sterile release rate for stopping growing age-structured populations

    International Nuclear Information System (INIS)

    Barclay, Hugh John

    2016-01-01

    A freely-growing age-structured population was modelled for growth and control by sterile male releases. Equilibrium populations yield critical sterile male release rates that would hold the population at equilibrium. It is shown here that these rates may be different from the release rates required to stop a growing population and bring it to an equilibrium. A computer simulation was constructed of this population and a parameter sensitivity analysis graphed the effects on the required sterile male release rate of fertility, mating delay in adult females, net juvenile survivorship, three adult survivorship curves, the time spent in the juvenile stages, and total life span. The adult survivorship curves had the greatest effect on the required sterile release rate for population elimination. The required release rate was also determined for Ceratitis capitata (Wiedemann) using survivorship and fertility data from a laboratory strain. The concepts of over-flooding ratio and release ratio were discussed and quantified for the cases above. (author)

  5. The role of elastomeric pumps in postoperative analgesia in orthopaedics and factors affecting their flow rate.

    Science.gov (United States)

    Theodorides, Anthony Andreas

    2017-12-01

    Elastomeric pumps are mechanical devices composed of an elastomeric balloon reservoir into which the drug to be infused is stored, a protective casing (used by some manufacturers), a flow controller and a wound catheter. In orthopaedics they are used to provide continuous local infiltration analgesia. In this way patients rely less on other routes of analgesia and thus avoid their systemic side effects. Studies have shown good response to analgesia with these pumps for the first 24 hours but their benefit is not as clear at 48 and 72 hours. There are numerous factors that affect the flow rate of elastomeric pumps. Some are inherent to all elastomeric pumps such as: the pressure exerted by the elastomeric balloon, catheter size, the vertical height of the pump in relation to the wound, viscosity and partial filling. There are also other factors which vary according to the manufacturer such as: the optimal temperature to obtain the desired flow rate as this directly affects viscosity, the dialysate that the analgesic drug is mixed with (ie normal saline or 5% dextrose), and the storage conditions of the fluid to be infused. It is thus essential to follow the clinical guidelines provided by the manufacturer in order to obtain the desired flow rate. Copyright the Association for Perioperative Practice.

  6. Fracture patterns and the energy release rate of phosphorene.

    Science.gov (United States)

    Liu, Ning; Hong, Jiawang; Pidaparti, Ramana; Wang, Xianqiao

    2016-03-14

    Phosphorene, also known as monolayer black phosphorus, has been enjoying popularity in electronic devices due to its superior electrical properties. However, it's relatively low Young's modulus, low fracture strength and susceptibility to structural failure have limited its application in mechanical devices. Therefore, in order to design more mechanically reliable devices that utilize phosphorene, it is necessary to explore the fracture patterns and energy release rate of phosphorene. In this study, molecular dynamics simulations are performed to investigate phosphorene's fracture mechanism. The results indicate that fracture under uniaxial tension along the armchair direction is attributed to a break in the interlayer bond angles, while failure in the zigzag direction is triggered by the break in both intra-layer angles and bonds. Furthermore, we developed a modified Griffith criterion to analyze the energy release rate of phosphorene and its dependence on the strain rates and orientations of cracks. Simulation results indicate that phosphorene's energy release rate remains almost unchanged in the armchair direction while it fluctuates intensively in the zigzag direction. Additionally, the strain rate was found to play a negligible role in the energy release rate. The geometrical factor α in the Griffith's criterion is almost constant when the crack orientation is smaller than 45 degree, regardless of the crack orientation and loading direction. Overall, these findings provide helpful insights into the mechanical properties and failure behavior of phosphorene.

  7. Maternal response to two electric breast pumps

    Science.gov (United States)

    Mechanical characteristics of breast pumps have been shown to influence milk extraction and hormone release in laboratory settings. However, few studies evaluate impact of differences in pump design on long-term breastfeeding success. This study evaluated the impact of a novel pump design on milk ex...

  8. Centrifugal pumps: fundamentals and classification

    International Nuclear Information System (INIS)

    Solar Manuel, A. M.

    2009-01-01

    Centrifugal pumps are usually employed to impulse water to elevate it, dose it or give it pressure or speed. They can be used with clean water or loaded with high solid concentration and don't work properly with air or another gas flow. There are another less used pumps, coming from volumetric or ram pumps to magnetic ones for specific uses. Centrifugal ones are rotokinetic pumps, like peripherical or lateral channel pumps. They work in a different way that non rotational kinetic ones and static ones. The work approaches their pre definition, selection, installation, operation and maintenance. It also review their morphology, hidromechanic principles and the basic elements pumps are made of. (Author)

  9. Minimizing transient influence in WHPA delineation: An optimization approach for optimal pumping rate schemes

    Science.gov (United States)

    Rodriguez-Pretelin, A.; Nowak, W.

    2017-12-01

    For most groundwater protection management programs, Wellhead Protection Areas (WHPAs) have served as primarily protection measure. In their delineation, the influence of time-varying groundwater flow conditions is often underestimated because steady-state assumptions are commonly made. However, it has been demonstrated that temporary variations lead to significant changes in the required size and shape of WHPAs. Apart from natural transient groundwater drivers (e.g., changes in the regional angle of flow direction and seasonal natural groundwater recharge), anthropogenic causes such as transient pumping rates are of the most influential factors that require larger WHPAs. We hypothesize that WHPA programs that integrate adaptive and optimized pumping-injection management schemes can counter transient effects and thus reduce the additional areal demand in well protection under transient conditions. The main goal of this study is to present a novel management framework that optimizes pumping schemes dynamically, in order to minimize the impact triggered by transient conditions in WHPA delineation. For optimizing pumping schemes, we consider three objectives: 1) to minimize the risk of pumping water from outside a given WHPA, 2) to maximize the groundwater supply and 3) to minimize the involved operating costs. We solve transient groundwater flow through an available transient groundwater and Lagrangian particle tracking model. The optimization problem is formulated as a dynamic programming problem. Two different optimization approaches are explored: I) the first approach aims for single-objective optimization under objective (1) only. The second approach performs multiobjective optimization under all three objectives where compromise pumping rates are selected from the current Pareto front. Finally, we look for WHPA outlines that are as small as possible, yet allow the optimization problem to find the most suitable solutions.

  10. Spare mitigation/retrieval mixer pumps

    International Nuclear Information System (INIS)

    Taylor, S.

    1995-01-01

    This document presents the functional design criteria for design, analysis, fabrication, testing, and installation of a waste tank mixer pump. The mixer pump will be operated to eliminate the periodic releases of large quantities of flammable gas (e.g., hydrogen) from Hanford Site waste tanks and also to accommodate retrieval of tank waste

  11. Experiments to Measure Hydrogen Release from Graphite Walls During Disruptions in DIII-D

    International Nuclear Information System (INIS)

    Hollmann, E.M.; Pablant, N.A.; Rudakov, D.L.; Boedo, J.A.; Brooks, N.H.; Jernigan, Thomas C.; Pigarov, A.Y.

    2009-01-01

    Spectroscopy and wall the bake-out measurements are performed in the DIII-D tokamak to estimate the amount of hydrogen stored in and released from the walls during disruptions. Both naturally occurring disruptions and disruptions induced by massive gas injection (MGI) are investigated. The measurements indicate that both types of disruptions cause a net release of order 10(21) hydrogen (or deuterium) atoms from the graphite walls. This is comparable to the pre-disruptions plasma particle inventory, so the released hydrogen is important for accurate modeling of disruptions. However, the amount of hydrogen released is small compared to the total saturated wall inventory of order 10(22)-10(23), So it appears that many disruptions are necessary to provide full pump-out of the vessel walls. (C) 2009 Published by Elsevier B.V.

  12. Electromagnetic pump

    International Nuclear Information System (INIS)

    Ito, Koji; Suetake, Norio; Aizawa, Toshie; Nakasaki, Masayoshi

    1998-01-01

    The present invention provides an electromagnetic pump suitable to a recycling pump for liquid sodium as coolants of an FBR type reactor. Namely, a stator module of the electromagnetic pump of the present invention comprises a plurality of outer laminate iron core units and outer stator modules stacked alternately in the axial direction. With such a constitution, even a long electromagnetic pump having a large number of outer stator coils can be manufactured without damaging electric insulation of the outer stator coils. In addition, the inner circumferential surface of the outer laminate iron cores is urged and brought into contact with the outer circumferential surface of the outer duct by an elastic material. With such a constitution, Joule loss heat generated in the outer stator coils and internal heat generated in the outer laminate iron cores can be released to an electroconductive fluid flowing the inner circumference of the outer duct by way of the outer duct. (I.S.)

  13. Structural health monitoring methods for the evaluation of prestressing forces and pre-release cracks

    Directory of Open Access Journals (Sweden)

    Hiba Abdel-Jaber

    2016-08-01

    Full Text Available Prestressed concrete bridges currently account for 45% of bridges built in the last five years in the United States. This has resulted in an increase in the number of deficient bridges composed of prestressed concrete, which requires a better understanding of the on-site performance of this building material. The use of new materials, such as high performance concrete, in conjunction with prestressing provides additional motivation for the creation of structural health monitoring (SHM methods for prestressed concrete. This paper identifies two parameters relevant to prestressed concrete, along with methods for their evaluation. The parameters evaluated are the prestressing force value at transfer and the width of pre-release cracks, both of which are indicators of structural performance. Improper transfer of the prestressing force can result in tensile stresses in the concrete that exceed capacity and result in cracks and/or excessive deflections. Pre-release cracks occur in the concrete prior to transfer of the prestressing force and are mainly caused by autogenous shrinkage and thermal gradients. Closure of the cracks is expected by virtue of prestressing force transfer. However, the extent of crack closure is important in order to guarantee durability and structural integrity. This paper presents an integral overview of two novel methods for the statistical evaluation of the two monitored parameters: prestressing forces and the width of pre-release cracks. Validation of the methods is performed through application to two structures, both of which are components of Streicker Bridge on the Princeton University campus. Uncertainties are evaluated and thresholds for unusual behavior are set through the application.

  14. Linac pre-injector

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    New accelerating column of the linac pre-injector, supporting frame and pumping system. This new system uses two mercury diffusion pumps (in the centre) and forms part of the modifications intended to increase the intensity of the linac. View taken during assembly in the workshop.

  15. Pumping machinery theory and practice

    CERN Document Server

    Badr, Hassan M

    2014-01-01

    Pumping Machinery Theory and Practice comprehensively covers the theoretical foundation and applications of pumping machinery. Key features: Covers characteristics of centrifugal pumps, axial flow pumps and displacement pumpsConsiders pumping machinery performance and operational-type problemsCovers advanced topics in pumping machinery including multiphase flow principles, and two and three-phase flow pumping systemsCovers different methods of flow rate control and relevance to machine efficiency and energy consumptionCovers different methods of flow rate control and relevance to machine effi

  16. Development of polymer film dosage forms of lidocaine for buccal administration. I. Penetration rate and release rate.

    Science.gov (United States)

    Okamoto, H; Taguchi, H; Iida, K; Danjo, K

    2001-12-13

    We examined the penetration rate of lidocaine (LC) through excised oral mucosa from hamster cheek pouch and the in vitro release rate of LC from film dosage forms with hydroxypropylcellulose (HPC) as a film base. Addition of glycyrrhizic acid (GL) to the HPC films increased the LC release rate almost GL-content-dependently, while an optimum GL content was observed for the LC penetration rate. No LC penetration was observed from an acidic aqueous solution (pH 3.4) of LC, suggesting only unionized LC can substantially penetrate through the mucosa. A significant relationship between the penetration rate of LC and the release rate of unionized LC was found, suggesting that the in vitro dissolution study is a useful tool to predict the penetration rate taking the unionized drug fraction into consideration.

  17. A comparison of the hourly output between the Ambu® Smart-Infuser™ Pain Pump and the On-Q Pump® with Select-A-Flow™ Variable Rate Controller with standard and overfill volumes.

    Science.gov (United States)

    Iliev, Peter; Bhalla, Tarun; Tobias, Joseph D

    2016-04-01

    The Ambu Smart-Infuser Pain Pump and the On-Q Pump with Select-a-Flow Variable Rate Controller are elastomeric devices with a flow regulator that controls the rate of infusion of a local anesthetic agent through a peripheral catheter. As a safety evaluation, we evaluated the infusion characteristics of these two devices when filled with manufacturer recommended standard volumes and when overfilled with a volume 50% in excess of that which is recommended. Nineteen disposable devices from the two manufacturers were used in this study. Nine were filled with 0.9% normal saline according to the respective manufacturers' recommendations (four Ambu pumps were filled with 650 ml and five On-Q pumps were filled with 550 ml) and 10 devices were 150% overfilled (five Ambu pumps were filled with 975 ml and five On-Q pumps were filled with 825 ml). All of the devices were set to infuse at 10 ml · h(-1) at room temperature (21°C) for 12 h. The fluid delivered during each 2-h period was measured using a graduated column. The On-Q pump (in the settings of normal fill and 150% overfill) delivered a significantly higher output per hour than the set rate during the first 8 h, while the Ambu pump delivered a value close to the set rate of 10 ml · h(-1). No significant difference in the hourly delivered output was noted for either device when comparing the normal fill to the 150% overfill groups. This investigation demonstrates that no change in the hourly output occurs with overfilling of these home infusion devices. However, as noted previously, the hourly output from the On-Q device is significantly higher than the set rate during the initial 8 h of infusion which could have potential clinical implications. © 2016 John Wiley & Sons Ltd.

  18. Electrokinetic pumps and actuators

    International Nuclear Information System (INIS)

    Phillip M. Paul

    2000-01-01

    Flow and ionic transport in porous media are central to electrokinetic pumping as well as to a host of other microfluidic devices. Electrokinetic pumping provides the ability to create high pressures (to over 10,000 psi) and high flow rates (over 1 mL/min) with a device having no moving parts and all liquid seals. The electrokinetic pump (EKP) is ideally suited for applications ranging from a high pressure integrated pump for chip-scale HPLC to a high flow rate integrated pump for forced liquid convection cooling of high-power electronics. Relations for flow rate and current fluxes in porous media are derived that provide a basis for analysis of complex microfluidic systems as well as for optimization of electrokinetic pumps

  19. Electrokinetic pumps and actuators

    Energy Technology Data Exchange (ETDEWEB)

    Phillip M. Paul

    2000-03-01

    Flow and ionic transport in porous media are central to electrokinetic pumping as well as to a host of other microfluidic devices. Electrokinetic pumping provides the ability to create high pressures (to over 10,000 psi) and high flow rates (over 1 mL/min) with a device having no moving parts and all liquid seals. The electrokinetic pump (EKP) is ideally suited for applications ranging from a high pressure integrated pump for chip-scale HPLC to a high flow rate integrated pump for forced liquid convection cooling of high-power electronics. Relations for flow rate and current fluxes in porous media are derived that provide a basis for analysis of complex microfluidic systems as well as for optimization of electrokinetic pumps.

  20. Controlling Object Heat Release Rate using Geometrical Features

    OpenAIRE

    Kraft, Stefan Marc

    2017-01-01

    An experimental study was conducted to determine the effect of complex geometries on the burning rate of materials made using additive manufacturing. Controlling heat release rate has applicability in limiting fire hazards as well as for designing fuels for optimal burning rate. The burning rate of a structure is a function of the material properties as well as the airflow through it, which is dictated by the geometry. This burning rate is generally proportional to the porosity for obj...

  1. Comparison of a wellpoint vacuum pump system to dual pump recovery system effectiveness for the extraction of light non-aqueous phase liquids

    International Nuclear Information System (INIS)

    Koll, C.S.; Palmerton, D.L. Jr.; Kunzel, R.G.

    1994-01-01

    The effectiveness of two light non-aqueous phase liquid (LNAPL) extraction systems is compared at a site in the Mid-New Jersey Atlantic Coastal Plains Region: an existing dual pump recovery system and a wellpoint vacuum pump system. Home heating oil was released to a shallow sand and gravel aquifer by a leaky underground distribution system in the early 1970s. Eight-inch-diameter dual pump recovery wells were used for the last nine years, to lower the water table and extract LNAPL at several spill sites located throughout a residential community of 1,500 homes. Several small LNAPL plumes still exist today with surface areas ranging from 400 ft 2 to over 28,000 ft 2 . LNAPL recovery peaked in 1985 using dual pump recovery systems, averaging 33 gallons per day (gpd). In 1987, four 24-inch wells were replaced by 11 8-inch-diameter recovery wells at six sites, and LNAPL recovery rates averaged 5 gpd. In recent years, the recovery of LNAPL has declined and when graphed, is asymptotic. In 1993, dual pump recovery of LNAPL averaged 0.3 gpd for all six sites

  2. Quantification of Na+,K+ pumps and their transport rate in skeletal muscle: Functional significance

    Science.gov (United States)

    2013-01-01

    During excitation, muscle cells gain Na+ and lose K+, leading to a rise in extracellular K+ ([K+]o), depolarization, and loss of excitability. Recent studies support the idea that these events are important causes of muscle fatigue and that full use of the Na+,K+-ATPase (also known as the Na+,K+ pump) is often essential for adequate clearance of extracellular K+. As a result of their electrogenic action, Na+,K+ pumps also help reverse depolarization arising during excitation, hyperkalemia, and anoxia, or from cell damage resulting from exercise, rhabdomyolysis, or muscle diseases. The ability to evaluate Na+,K+-pump function and the capacity of the Na+,K+ pumps to fill these needs require quantification of the total content of Na+,K+ pumps in skeletal muscle. Inhibition of Na+,K+-pump activity, or a decrease in their content, reduces muscle contractility. Conversely, stimulation of the Na+,K+-pump transport rate or increasing the content of Na+,K+ pumps enhances muscle excitability and contractility. Measurements of [3H]ouabain binding to skeletal muscle in vivo or in vitro have enabled the reproducible quantification of the total content of Na+,K+ pumps in molar units in various animal species, and in both healthy people and individuals with various diseases. In contrast, measurements of 3-O-methylfluorescein phosphatase activity associated with the Na+,K+-ATPase may show inconsistent results. Measurements of Na+ and K+ fluxes in intact isolated muscles show that, after Na+ loading or intense excitation, all the Na+,K+ pumps are functional, allowing calculation of the maximum Na+,K+-pumping capacity, expressed in molar units/g muscle/min. The activity and content of Na+,K+ pumps are regulated by exercise, inactivity, K+ deficiency, fasting, age, and several hormones and pharmaceuticals. Studies on the α-subunit isoforms of the Na+,K+-ATPase have detected a relative increase in their number in response to exercise and the glucocorticoid dexamethasone but have not

  3. Quantification of Na+,K+ pumps and their transport rate in skeletal muscle: functional significance.

    Science.gov (United States)

    Clausen, Torben

    2013-10-01

    During excitation, muscle cells gain Na(+) and lose K(+), leading to a rise in extracellular K(+) ([K(+)]o), depolarization, and loss of excitability. Recent studies support the idea that these events are important causes of muscle fatigue and that full use of the Na(+),K(+)-ATPase (also known as the Na(+),K(+) pump) is often essential for adequate clearance of extracellular K(+). As a result of their electrogenic action, Na(+),K(+) pumps also help reverse depolarization arising during excitation, hyperkalemia, and anoxia, or from cell damage resulting from exercise, rhabdomyolysis, or muscle diseases. The ability to evaluate Na(+),K(+)-pump function and the capacity of the Na(+),K(+) pumps to fill these needs require quantification of the total content of Na(+),K(+) pumps in skeletal muscle. Inhibition of Na(+),K(+)-pump activity, or a decrease in their content, reduces muscle contractility. Conversely, stimulation of the Na(+),K(+)-pump transport rate or increasing the content of Na(+),K(+) pumps enhances muscle excitability and contractility. Measurements of [(3)H]ouabain binding to skeletal muscle in vivo or in vitro have enabled the reproducible quantification of the total content of Na(+),K(+) pumps in molar units in various animal species, and in both healthy people and individuals with various diseases. In contrast, measurements of 3-O-methylfluorescein phosphatase activity associated with the Na(+),K(+)-ATPase may show inconsistent results. Measurements of Na(+) and K(+) fluxes in intact isolated muscles show that, after Na(+) loading or intense excitation, all the Na(+),K(+) pumps are functional, allowing calculation of the maximum Na(+),K(+)-pumping capacity, expressed in molar units/g muscle/min. The activity and content of Na(+),K(+) pumps are regulated by exercise, inactivity, K(+) deficiency, fasting, age, and several hormones and pharmaceuticals. Studies on the α-subunit isoforms of the Na(+),K(+)-ATPase have detected a relative increase in their

  4. A prison mental health in-reach model informed by assertive community treatment principles: evaluation of its impact on planning during the pre-release period, community mental health service engagement and reoffending.

    Science.gov (United States)

    McKenna, Brian; Skipworth, Jeremy; Tapsell, Rees; Madell, Dominic; Pillai, Krishna; Simpson, Alexander; Cavney, James; Rouse, Paul

    2015-12-01

    It is well recognised that prisoners with serious mental illness (SMI) are at high risk of poor outcomes on return to the community. Early engagement with mental health services and other community agencies could provide the substrate for reducing risk. To evaluate the impact of implementing an assertive community treatment informed prison in-reach model of care (PMOC) on post-release engagement with community mental health services and on reoffending rates. One hundred and eighty prisoners with SMI released from four prisons in the year before implementation of the PMOC were compared with 170 such prisoners released the year after its implementation. The assertive prison model of care was associated with more pre-release contacts with community mental health services and contacts with some social care agencies in some prisons. There were significantly more post-release community mental health service engagements after implementation of this model (Z = -2.388, p = 0.02). There was a trend towards reduction in reoffending rates after release from some of the prisons (Z =1.82, p = 0.07). Assertive community treatment applied to prisoners with mental health problems was superior to 'treatment as usual', but more work is needed to ensure that agencies will engage prisoners in pre-release care. The fact that the model showed some benefits in the absence of any increase in resources suggests that it may be the model per se that is effective. Copyright © 2014 John Wiley & Sons, Ltd.

  5. Leak rate analysis of the Westinghouse Reactor Coolant Pump

    International Nuclear Information System (INIS)

    Boardman, T.; Jeanmougin, N.; Lofaro, R.; Prevost, J.

    1985-07-01

    An independent analysis was performed by ETEC to determine what the seal leakage rates would be for the Westinghouse Reactor Coolant Pump (RCP) during a postulated station blackout resulting from loss of ac electric power. The object of the study was to determine leakage rates for the following conditions: Case 1: All three seals function. Case 2: No. 1 seal fails open while Nos. 2 and 3 seals function. Case 3: All three seals fail open. The ETEC analysis confirmed Westinghouse calculations on RCP seal performance for the conditions investigated. The leak rates predicted by ETEC were slightly lower than those predicted by Westinghouse for each of the three cases as summarized below. Case 1: ETEC predicted 19.6 gpm, Westinghouse predicted 21.1 gpm. Case 2: ETEC predicted 64.7 gpm, Westinghouse predicted 75.6 gpm. Case 3: ETEC predicted 422 gpm, Westinghouse predicted 480 gpm. 3 refs., 22 figs., 6 tabs

  6. Measurement of semiochemical release rates with a dedicated environmental control system

    Science.gov (United States)

    Heping Zhu; Harold W. Thistle; Christopher M. Ranger; Hongping Zhou; Brian L. Strom

    2015-01-01

    Insect semiochemical dispensers are commonly deployed under variable environmental conditions over a specified period. Predictions of their longevity are hampered by a lack of methods to accurately monitor and predict how primary variables affect semiochemical release rate. A system was constructed to precisely determine semiochemical release rates under...

  7. Pressure variation characteristics at trapping region in oil hydraulic piston pumps

    International Nuclear Information System (INIS)

    Kim, Jong Ki; Jung, Jae Youn; Rho, Byung Joon; Song, Kyu Keun; Oh, Seok Hyung

    2003-01-01

    Pressure variation is one of the major sources on noise emission in the oil hydraulic piston pumps. Therefore, it is necessary to clarify about pressure variation characteristics of the oil hydraulic piston pumps to reduce noise. Pressure variations in a cylinder at trapping region were measured during pump working period with discharge pressures, rotational speeds. The effect of pre-compression of the discharge port with three types valve plates also investigated. It was found that the pressure variation characteristics of oil hydraulic piston pumps deeply related with pre-compression design of the discharge port. Also, it was found that the pressure overshoot at trapping region can reduce by use of pre-compression at the end of the discharge port in valve plate

  8. Release rates of soluble species at Yucca Mountain

    International Nuclear Information System (INIS)

    Lee, W.W.-L.; Pigford, T.H.

    1989-02-01

    Experimental leaching of spent fuel shows that some fission product species are preferentially released upon contact with water. We analyze the conservative case of bare spent fuel in contact with saturated tuff using diffusional mass transfer analysis. For the parameter values used, the USNRC release rate limit is not exceeded, except for 99 Tc. The presence of a container and the distribution of water contact over time will assist in meeting this criterion. 6 figs., 2 tabs

  9. Mitigation of Tank 241-SY-101 by pump mixing: Results of testing phases A and B

    Energy Technology Data Exchange (ETDEWEB)

    Allemann, R.T.; Antoniak, Z.I.; Chvala, W.D.; Friley, J.R.; Gregory, W.B.; Hudson, J.D.; Michener, T.E.; Panisko, F.E.; Stewart, C.W.; Wise, B.M. [Pacific Northwest Lab., Richland, WA (United States); Efferding, L.E.; Fadeff, J.G.; Irwin, J.J.; Kirch, N.W. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-03-01

    A spare mixing pump from the Hanford Grout Program was installed in Hanford double-shell waste Tank 241-SY-101 on July 3, 1993, after being modified to take advantage of waste stratification. It was anticipated that pump mixing would prevent large episodic flammable gas releases that had been occurring about every 100-150 days. A cautious initial test plan, called Phase A, was run to find how the pump and tank would behave in response to very brief and gentle pump operation. No large gas releases were triggered, and the pump performed well except for two incidents of nozzle plugging. On October 21, 1993, the next test series, Phase B, began, and the pump was applied more aggressively to mix the tank contents and mitigate uncontrolled gas releases. Orienting the pump in new directions released large volumes of gas and reduced the waste level to a near-record low. Results of the entire period from pump installation to the end of Phase B on December 17, 1993, are presented in detail in this document. Though long-term effects require further evaluation, we conclude from these data that the jet mixer pump is an effective means of controlling flammable gas release and that it has met the success criteria for mitigation in this tank.

  10. Glucose Pump Test can be Used to Measure Blood Flow Rate of ...

    African Journals Online (AJOL)

    The aim of study is to determine whether glucose pump test (GPT) is used for surveillance of native AV fistulas by using Doppler US as reference. Methods: In 93 chronic hemodialysis patients with native AV fistula, blood flow rates were measured by Doppler US and GPT. For GPT, glucose was infused to 16 mL/min by ...

  11. Phenazopyridine-phthalimide nano-cocrystal: Release rate and oral bioavailability enhancement.

    Science.gov (United States)

    Huang, Yu; Li, Jin-Mei; Lai, Zhi-Hui; Wu, Jun; Lu, Tong-Bu; Chen, Jia-Mei

    2017-11-15

    Both cocrystal and nanocrystal technologies have been widely used in the pharmaceutical development for poorly soluble drugs. However, the synergistic effects due to the integration of these two technologies have not been well investigated. The aim of this study is to develop a nano-sized cocrystal of phenazopyridine (PAP) with phthalimide (PI) to enhance the release rate and oral bioavailability of PAP. A PAP-PI nano-cocrystal with particle diameter of 21.4±0.1nm was successfully prepared via a sonochemical approach and characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamic light scattering (DLS) analysis. An in vitro release study revealed a significant release rate enhancement for PAP-PI nano-cocrystal as compared to PAP-PI cocrystal and PAP hydrochloride salt. Further, a comparative oral bioavailability study in rats indicated significant improvement in C max and oral bioavailability (AUC 0-∞ ) by 1.39- and 2.44-fold, respectively. This study demonstrated that this novel nano-cocrystal technology can be a new promising option to improve release rate and absorption of poorly soluble compounds in the pharmaceutical industry. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Hindered disulfide bonds to regulate release rate of model drug from mesoporous silica.

    Science.gov (United States)

    Nadrah, Peter; Maver, Uroš; Jemec, Anita; Tišler, Tatjana; Bele, Marjan; Dražić, Goran; Benčina, Mojca; Pintar, Albin; Planinšek, Odon; Gaberšček, Miran

    2013-05-01

    With the advancement of drug delivery systems based on mesoporous silica nanoparticles (MSNs), a simple and efficient method regulating the drug release kinetics is needed. We developed redox-responsive release systems with three levels of hindrance around the disulfide bond. A model drug (rhodamine B dye) was loaded into MSNs' mesoporous voids. The pore opening was capped with β-cyclodextrin in order to prevent leakage of drug. Indeed, in absence of a reducing agent the systems exhibited little leakage, while the addition of dithiothreitol cleaved the disulfide bonds and enabled the release of cargo. The release rate and the amount of released dye were tuned by the level of hindrance around disulfide bonds, with the increased hindrance causing a decrease in the release rate as well as in the amount of released drug. Thus, we demonstrated the ability of the present mesoporous systems to intrinsically control the release rate and the amount of the released cargo by only minor structural variations. Furthermore, an in vivo experiment on zebrafish confirmed that the present model delivery system is nonteratogenic.

  13. Off-pump versus On-pump Coronary Artery Bypass Grafting in Frail Patients: Study Protocol for the FRAGILE Multicenter Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Omar Asdrúbal Vilca Mejía

    Full Text Available Abstract Introduction: Advances in modern medicine have led to people living longer and healthier lives. Frailty is an emerging concept in medicine yet to be explored as a risk factor in cardiac surgery. When it comes to CABG surgery, randomized controlled clinical trials have primarily focused on low-risk (ROOBY, CORONARY, elevated-risk (GOPCABE or high-risk patients (BBS, but not on frail patients. Therefore, we believe that off-pump CABG could be an important technique in patients with limited functional capacity to respond to surgical stress. In this study, the authors introduce the new national, multicenter, randomized, controlled trial "FRAGILE", to be developed in the main cardiac surgery centers of Brazil, to clarify the potential benefit of off-pump CABG in frail patients. Methods: FRAGILE is a two-arm, parallel-group, multicentre, individually randomized (1:1 controlled trial which will enroll 630 patients with blinded outcome assessment (at 30 days, 6 months, 1 year, 2 years and 3 years, which aims to compare adverse cardiac and cerebrovascular events after off-pump versus on-pump CABG in pre-frail and frail patients. Primary outcomes will be all-cause mortality, acute myocardial infarction, cardiac arrest with successful resuscitation, low cardiac output syndrome/cardiogenic shock, stroke, and coronary reintervention. Secondary outcomes will be major adverse cardiac and cerebrovascular events, operative time, mechanical ventilation time, hyperdynamic shock, new onset of atrial fibrillation, renal replacement therapy, reoperation for bleeding, pneumonia, length of stay in intensive care unit, length of stay in hospital, number of units of blood transfused, graft patency, rate of complete revascularization, neurobehavioral outcomes after cardiac surgery, quality of life after cardiac surgery and costs. Discussion: FRAGILE trial will determine whether off-pump CABG is superior to conventional on-pump CABG in the surgical treatment of

  14. Scavenged body heat powered infusion pump

    International Nuclear Information System (INIS)

    Bell, Alexander; Ehringer, William D; McNamara, Shamus

    2013-01-01

    An infusion pump powered by body heat is investigated in this paper, with the goal of addressing the needs of dermal wound healing. The infusion pump incorporates a Knudsen gas pump, a type of thermally driven pump, to pneumatic push the pharmaceutical agent from a reservoir. Two designs are considered: an integrated pump and reservoir, and a design with cascaded pump and reservoir. Thermal models are developed for both pumps, and the simulations agree well with the experimental results. The integrated pump and reservoir design uses hydrophobic materials to prevent a flow from occurring unless the infusion pump is placed on a human body. Flow rates in the µL min −1 range for the integrated pump and reservoir, and approximately 70 µL min −1 for the cascaded pump were obtained. The dynamic behavior of the cascaded pump is described based on the thermal models. Multiple copies of the cascaded pump are easily made in series or parallel, to increase either the pressure or the flow rate. The flow rate of multiple pumps in series does not change, and the pressure of multiple pumps in parallel does not change. (paper)

  15. Analysis of the status of pre-release cracks in prestressed concrete structures using long-gauge sensors

    International Nuclear Information System (INIS)

    Abdel-Jaber, H; Glisic, B

    2015-01-01

    Prestressed structures experience limited tensile stresses in concrete, which limits or completely eliminates the occurrence of cracks. However, in some cases, large tensile stresses can develop during the early age of the concrete due to thermal gradients and shrinkage effects. Such stresses can cause early-age cracks, termed ‘pre-release cracks’, which occur prior to the transfer of the prestressing force. When the prestressing force is applied to the cross-section, it is assumed that partial or full closure of the cracks occurs by virtue of the force transfer through the cracked cross-section. Verification of the closure of the cracks after the application of the prestressing force is important as it can either confirm continued structural integrity or indicate and approximate reduced structural capacity. Structural health monitoring (SHM) can be used for this purpose. This paper researches an SHM method that can be applied to prestressed beam structures to assess the condition of pre-release cracks. The sensor network used in this method consists of parallel long-gauge fiber optic strain sensors embedded in the concrete cross-sections at various locations. The same network is used for damage detection, i.e. detection and characterization of the pre-release cracks, and for monitoring the prestress force transfer. The method is validated on a real structure, a curved continuous girder. Results from the analysis confirm the safety and integrity of the structure. The method and its application are presented in this paper. (paper)

  16. Analysis of the status of pre-release cracks in prestressed concrete structures using long-gauge sensors

    Science.gov (United States)

    Abdel-Jaber, H.; Glisic, B.

    2015-02-01

    Prestressed structures experience limited tensile stresses in concrete, which limits or completely eliminates the occurrence of cracks. However, in some cases, large tensile stresses can develop during the early age of the concrete due to thermal gradients and shrinkage effects. Such stresses can cause early-age cracks, termed ‘pre-release cracks’, which occur prior to the transfer of the prestressing force. When the prestressing force is applied to the cross-section, it is assumed that partial or full closure of the cracks occurs by virtue of the force transfer through the cracked cross-section. Verification of the closure of the cracks after the application of the prestressing force is important as it can either confirm continued structural integrity or indicate and approximate reduced structural capacity. Structural health monitoring (SHM) can be used for this purpose. This paper researches an SHM method that can be applied to prestressed beam structures to assess the condition of pre-release cracks. The sensor network used in this method consists of parallel long-gauge fiber optic strain sensors embedded in the concrete cross-sections at various locations. The same network is used for damage detection, i.e. detection and characterization of the pre-release cracks, and for monitoring the prestress force transfer. The method is validated on a real structure, a curved continuous girder. Results from the analysis confirm the safety and integrity of the structure. The method and its application are presented in this paper.

  17. High-vacuum plasma pump

    International Nuclear Information System (INIS)

    Dorodnov, A.M.; Minajchev, V.E.; Miroshkin, S.I.

    1980-01-01

    The action of an electric-arc high-vacuum pump intended for evacuating the volumes in which the operation processes are followed by a high gas evolution is considered. The operation of the pump is based on the principle of controlling the getter feed according to the gas load and effect of plasma sorbtion pumping. The pump performances are given. The starting pressure is about 5 Pa, the limiting residual pressure is about 5x10 -6 Pa, the pumping out rate of nitrogen in the pressure range 5x10 -5 -5x10 -3 Pa accounts for about 4000 l/s, the power consumption comes to 6 kW. Analyzing the results of the test operation of the pump, it has been concluded that its principal advantages are the high starting pressure, controlled getter feed rate and possibility of pumping out the gases which are usually pumped out with difficulty. The operation reliability of the pump is defined mainly by reliable operation of the ignition system of the vacuum arc [ru

  18. In situ release rates of Cu and Zn from commercial antifouling paints at different salinities.

    Science.gov (United States)

    Lagerström, Maria; Lindgren, J Fredrik; Holmqvist, Albin; Dahlström, Mia; Ytreberg, Erik

    2018-02-01

    Antifouling paints are environmentally risk assessed based on their biocidal release rates to the water phase. In situ release rates of copper (Cu) and zinc (Zn) were derived for five commercial paints in two recreational marinas with different salinities (5 and 14 PSU) using an X-Ray Fluorescence spectrometer (XRF). Salinity was found to significantly affect the Cu release, with twice the amount of Cu released at the higher salinity, while its influence on the Zn release was paint-specific. Site-specific release rates for water bodies with salinity gradients, e.g. the Baltic Sea, are therefore necessary for more realistic risk assessments of antifouling paints. Furthermore, the in situ release rates were up to 8 times higher than those generated using standardized laboratory or calculation methods. The environmental risk assessment repeated with the field release rates concludes that it is questionable whether the studied products should be allowed on the Swedish market. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. TFCX pumped limiter and vacuum pumping system design and analysis

    International Nuclear Information System (INIS)

    Haines, J.R.

    1985-04-01

    Impurity control system design and performance studies were performed in support of the Tokamak Fusion Core Experiment (TFCX) pre-conceptual design. Efforts concentrated on pumped limiter and vacuum pumping system design configuration, thermal/mechanical and erosion lifetime performance of the limiter protective surface, and helium ash removal performance. The reference limiter design forms a continuous toroidal belt at the bottom of the device and features a flat surface with a single leading edge. The vacuum pumping system features large vacuum ducts (diameter approximately 1 m) and high-speed, compound cryopumps. Analysis results indicate that the limiter/vacuum pumping system design provides adequate helium ash removal. Erosion, primarily by disruption-induced vaporization and/or melting, limits the protective surface lifetime to about one calendar year or only about 60 full-power hours of operation. In addition to evaluating impurity control system performance for nominal TFCX conditions, these studies attempt to focus on the key plasma physics and engineering design issues that should be addressed in future research and development programs

  20. Pre-Release Consumption of Methyl Eugenol Increases the Mating Competitiveness of Sterile Males of the Oriental Fruit Fly, Bactrocera dorsalis, in Large Field Enclosures

    Science.gov (United States)

    Shelly, Todd E.; Edu, James; McInnis, Donald

    2010-01-01

    The sterile insect technique may be implemented to control populations of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), when environmental concerns preclude widespread use of chemical attractants or toxicants. The goal of the present study was to evaluate whether the mating competitiveness of sterile B. dorsalis males could be increased via pre-release feeding on methyl eugenol. Males of the oriental fruit fly are strongly attracted to this plant-borne compound, which they ingest and use in the synthesis of the sex pheromone. Previous studies conducted in the laboratory and small field-cages have shown that males given methyl eugenol produce a more attractive pheromone for females and have a higher mating success rate than males denied methyl eugenol. Here, levels of egg sterility were compared following the release of wild-like flies and either methyl eugenol-fed (treated) or methyl eugenol-deprived (control) sterile males in large field enclosures at four over flooding ratios ranging from 5:1 to 60:1 (sterile: wild-like males). Treated sterile males were fed methyl eugenol for 1–4 h (depending on the over flooding ratio tested) 3 d prior to release. Eggs were dissected from introduced fruits (apples), incubated in the laboratory, and scored for hatch rate. The effect of methyl eugenol was most pronounced at lower over flooding ratios. At the 5:1 and 10:1 over flooding ratios, the level of egg sterility observed for treated, sterile males was significantly greater than that observed for control, sterile males. In addition, the incidence of egg sterility reported for treated sterile males at these lower over flooding ratios was similar to that noted for treated or control sterile males at the 30:1 or 60:1 over flooding ratios. This latter result, in particular, suggests that pre-release feeding on methyl eugenol allows for a reduction in the number of sterile flies that are produced and released, thus increasing the cost

  1. Tritium breeding and release-rate kinetics from neutron-irradiated lithium oxide

    International Nuclear Information System (INIS)

    Quanci, J.F.

    1989-01-01

    The research encompasses the measurement of the tritium breeding and release-rate kinetics from lithium oxide, a ceramic tritium-breeding material. A thermal extraction apparatus which allows the accurate measurement of the total tritium inventory and release rate from lithium oxide samples under different temperatures, pressures and carrier-gas compositions with an uncertainty not exceeding 3% was developed. The goal of the Lithium Blanket Module program was to determine if advanced computer codes could accurately predict the tritium production in the lithium oxide blanket of a fusion power plant. A fusion blanket module prototype, was built and irradiated with a deuterium-tritium fusion-neutron source. The tritium production throughout the module was modeled with the MCNP three dimensional Monte Carlo code and was compared to the assay of the tritium bred in the module. The MCNP code accurately predicted tritium-breeding trends but underestimated the overall tritium breeding by 30%. The release rate of tritium from small grain polycrystalline sintered lithium oxide with a helium carrier gas from 300 to 450 C was found to be controlled by the first order surface desorption of mono-tritiated water. When small amounts of hydrogen were added to the helium carrier gas, the first order rate constant increased from the isotopic exchange of hydrogen for tritium at the lithium oxide surface occurring in parallel with the first order desorption process. The isotopic-exchange first order rate constant temperature dependence and hydrogen partial pressure dependence were evaluated. Large single crystals of lithium oxide were fabricated by the vacuum fusion technique. The release rate of tritium from the large single crystals was found to be controlled by diffusion, and the mixed diffusion-desorption controlled release regime

  2. Experimental study on the simple water hammer pump; Kan`igata water hammer pump ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Muto, M; Ushiyama, I [Ashikaga Institute of Technology, Tochigi (Japan)

    1997-11-25

    Outlined herein are experimental results with a water hammer pump. It is a unique pump in that it depends only on potential energy of water to pump-up water. Water flows downwards from a reservoir at a high position into the pump , and is released from the exhaust valve. When velocity of water flowing in the pipe reaches a certain level, hydraulic force exceeds gravity of the exhaust valve to rapidly closes it, which is accompanied by rapid increase in pressure in the pump. High-pressure water flows into the air chamber, after pushing up the lifting valve, to compress air in the chamber. The lifting valve is closed, when pressure in the air chamber exceeds that in the pump, to pump up water in the chamber through the lifting pipe. Closure of the lifting valve produces a negative pressure within the pump, which, together with gravity of the exhaust valve, opens the valve again. The pump lifts water at 1.64l/min under the conditions of head: 3m and lift: 6m at an efficiency of 48.1%. 1 ref., 4 fig., 2 tab.

  3. Miniature stick-packaging--an industrial technology for pre-storage and release of reagents in lab-on-a-chip systems.

    Science.gov (United States)

    van Oordt, Thomas; Barb, Yannick; Smetana, Jan; Zengerle, Roland; von Stetten, Felix

    2013-08-07

    Stick-packaging of goods in tubular-shaped composite-foil pouches has become a popular technology for food and drug packaging. We miniaturized stick-packaging for use in lab-on-a-chip (LOAC) systems to pre-store and on-demand release the liquid and dry reagents in a volume range of 80-500 μl. An integrated frangible seal enables the pressure-controlled release of reagents and simplifies the layout of LOAC systems, thereby making the package a functional microfluidic release unit. The frangible seal is adjusted to defined burst pressures ranging from 20 to 140 kPa. The applied ultrasonic welding process allows the packaging of temperature sensitive reagents. Stick-packs have been successfully tested applying recovery tests (where 99% (STDV = 1%) of 250 μl pre-stored liquid is released), long-term storage tests (where there is loss of only <0.5% for simulated 2 years) and air transport simulation tests. The developed technology enables the storage of a combination of liquid and dry reagents. It is a scalable technology suitable for rapid prototyping and low-cost mass production.

  4. 13 CFR 123.406 - What is the interest rate on a pre-disaster mitigation loan?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What is the interest rate on a pre... ADMINISTRATION DISASTER LOAN PROGRAM Pre-Disaster Mitigation Loans § 123.406 What is the interest rate on a pre-disaster mitigation loan? The interest rate on a pre-disaster mitigation loan will be fixed at 4 percent...

  5. Scroll vacuum pump

    Energy Technology Data Exchange (ETDEWEB)

    Morishita, Etsuo; Suganami, Takuya; Nishida, Mitsuhiro; Kitora, Yoshihisa; Yamamoto, Sakuei; Fujii, Kosaburo

    1988-02-25

    An effort is made to apply a scroll machine to development of a vacuum pump. In view of mechanical simplification and load patterns, the vacuum pump uses a rotating mechanism to produce paired vortices rotating around each center. Chip seal and atmospheric pressure are utilized for axial gap sealing while a spring and atmospheric pressure for the radial gap sealing. In both gaps, the sealing direction is stationary relative to the environment during rotation, making it much easier to achieve effective sealing as compared to oscillating pumps. Since the compression ratio is high in vacuum pumps, a zero top clearance form is adopted for the central portion of vortices and an gas release valve is installed in the rotating axis. A compact Oldham coupling with a small inertia force is installed behind the vortices to maintain the required phase relations between the vortices. These improvements result in a vacuum of 1 Pa for dry operation and 10/sup -2/ Pa for oil flooded operation of a single-stage scroll machine at 1800 rpm. (5 figs, 1 tab, 4 refs)

  6. Research on release rate of volatile organic compounds in typical vessel cabin

    Directory of Open Access Journals (Sweden)

    ZHANG Jinlan

    2018-02-01

    Full Text Available [Objectives] Volatile Organic Compounds (VOC should be efficiently controlled in vessel cabins to ensure the crew's health and navigation safety. As an important parameter, research on release rate of VOCs in cabins is required. [Methods] This paper develops a method to investigate this parameter of a ship's cabin based on methods used in other closed indoor environments. A typical vessel cabin is sampled with Tenax TA tubes and analyzed by Automated Thermal Desorption-Gas Chromatography-Mass Spectrometry (ATD-GC/MS. The lumped mode is used and the release rate of Benzene, Toluene, Ethylbenzene and Xylene (BTEX, the typical representatives of VOCs, is obtained both in closed and ventilated conditions. [Results] The results show that the content of xylene and Total Volatile Organic Compounds (TVOC exceed the indoor environment standards in ventilated conditions. The BTEX release rate is similar in both conditions except for the benzene. [Conclusions] This research builds a method to measure the release rate of VOCs, providing references for pollution character evaluation and ventilation and purification system design.

  7. Measurement of very low release rates of corrosion products in high temperature water

    International Nuclear Information System (INIS)

    Hermansson, H.-P.; Falk, I.

    1984-01-01

    A radiotracer technique has been developed for the measurement of release rates from nuclear reactor materials and it has been tested in a number of experiments. THis article, which forms the first part in a series, describes the experimental loop, the experimental technique and the preliminary results. Experiments were carried out on 18Cr8Ni stainless steel and on Inconel X750 in BWR primary system and feed water environments. The result show that a steady state in the release rate is achieved after operation for approximately 600 h. The release rate depends on the elemental concentration in the material and on the chemical and physical environments. Typical release rates for an 18Cr8Ni stainless steel and Inconel X750 in a BWR primary system environment were found to be 5 mdm and 8 mdm respectively. (Authors)

  8. Long-term safety issues associated with mixer pump operation

    International Nuclear Information System (INIS)

    Kubic, W.L. Jr.

    1994-01-01

    In this report, we examine several long-term issues: the effect of pump operation on future gas release events (GREs), uncontrolled chemical reactions, chronic toxic gas releases, foaming, and erosion and corrosion. Heat load in excess of the design limit, uncontrolled chemical reactions, chronic toxic gas releases, foaming, and erosion and corrosion have been shown not to be safety concerns. The effect of pump operation on future GREs could not be quantified. The problem with evaluating the long-term effects of pump operation on GREs is a lack of knowledge and uncertainty. In particular, the phenomena governing gas retention, particle size distribution, and settling are not well understood, nor are the interactions among these factors understood. There is a possibility that changes in these factors could increase the size of future GREs. Bounding estimates of the potential increase in size of GREs are not possible because of a lack of engineering data. Proper management of the hazards can reduce, but not eliminate, the possibility of undesirable changes. Maintaining temperature within the historical limits can reduce the possibility of undesirable changes. A monitoring program to detect changes in the gas composition and crust thickness will help detect slowly occurring changes. Because pump operation has be shown to eliminate GREs, continued pump operation can eliminate the hazards associated with future GREs

  9. Inverse modelling of radionuclide release rates using gamma dose rate observations

    Science.gov (United States)

    Hamburger, Thomas; Evangeliou, Nikolaos; Stohl, Andreas; von Haustein, Christoph; Thummerer, Severin; Wallner, Christian

    2015-04-01

    Severe accidents in nuclear power plants such as the historical accident in Chernobyl 1986 or the more recent disaster in the Fukushima Dai-ichi nuclear power plant in 2011 have drastic impacts on the population and environment. Observations and dispersion modelling of the released radionuclides help to assess the regional impact of such nuclear accidents. Modelling the increase of regional radionuclide activity concentrations, which results from nuclear accidents, underlies a multiplicity of uncertainties. One of the most significant uncertainties is the estimation of the source term. That is, the time dependent quantification of the released spectrum of radionuclides during the course of the nuclear accident. The quantification of the source term may either remain uncertain (e.g. Chernobyl, Devell et al., 1995) or rely on estimates given by the operators of the nuclear power plant. Precise measurements are mostly missing due to practical limitations during the accident. The release rates of radionuclides at the accident site can be estimated using inverse modelling (Davoine and Bocquet, 2007). The accuracy of the method depends amongst others on the availability, reliability and the resolution in time and space of the used observations. Radionuclide activity concentrations are observed on a relatively sparse grid and the temporal resolution of available data may be low within the order of hours or a day. Gamma dose rates, on the other hand, are observed routinely on a much denser grid and higher temporal resolution and provide therefore a wider basis for inverse modelling (Saunier et al., 2013). We present a new inversion approach, which combines an atmospheric dispersion model and observations of radionuclide activity concentrations and gamma dose rates to obtain the source term of radionuclides. We use the Lagrangian particle dispersion model FLEXPART (Stohl et al., 1998; Stohl et al., 2005) to model the atmospheric transport of the released radionuclides. The

  10. BIOMATERIALS FOR ROTARY BLOOD PUMPS

    NARCIS (Netherlands)

    VANOEVEREN, W

    Rotary blood pumps are used for cardiac assist and cardiopulmonary support since mechanical blood damage is less than with conventional roller pumps. The high shear rate in the rotary pump and the reduced anticoagulation of the patient during prolonged pumping enforces high demands on the

  11. Coast-down model based on rated parameters of reactor coolant pump

    International Nuclear Information System (INIS)

    Jiang Maohua; Zou Zhichao; Wang Pengfei; Ruan Xiaodong

    2014-01-01

    For a sudden loss of power in reactor coolant pump (RCP), a calculation model of rotor speed and flow characteristics based on rated parameters was studied. The derived model was verified by comparing with the power-off experimental data of 100D RCP. The results indicate that it can be used in preliminary design calculation and verification analysis. Then a design criterion of RCP was described based on the calculation model. The moment of inertia in AP1000 RCP was verified by this criterion. (authors)

  12. Mechanical pumping at low temperature

    International Nuclear Information System (INIS)

    Perin, J.P.; Claudet, G.; Disdier, F.

    1995-01-01

    This novel concept consist of a mechanical pump able to run at low temperature (25K). Since gas density varies inversely with temperature, this pump would deliver much higher mass flow rate than at room temperature for a given size. Advantages of this concept are order of magnitude reduction in size, weight, when compared to a conventional pump scaled to perform the same mass flow rate at room temperature. This pump would be a solution to allow continuously tritium extraction and minimize the mass inventory. (orig.)

  13. Reactor having coolant recycling pump

    International Nuclear Information System (INIS)

    Goto, Tadashi; Karatsuka, Shigeki; Yamamoto, Hajime.

    1991-01-01

    In a coolant recycling pump for an LMFBR type reactor, vertical grooves are formed to a static portion which surrounds a pump shaft as far as the lower end thereof. Sodium mists present in an annular gap of the pump shaft form a rotational flow, lose its centrifugal force at the grooved portion and are collected positively to the grooved portion. Further, since the rotational flow in the grooved channel is in a state of a cavity flow, the pressure is released in the grooved portion and a secondary eddy current is formed thereby providing a depressurized state. Accordingly, by a synergestic effect of the centrifugal force and the cavity flow, sodium mists can be recovered completely. (T.M.)

  14. Operational experience in mitigating flammable gas releases from Hanford Site Tank 241-SY-101

    International Nuclear Information System (INIS)

    Lentsch, J.W.; Babad, H.; Kirch, N.W.

    1995-01-01

    Flammable gases consisting of hydrogen, nitrous oxide, ammonia, and methane are periodically released from Hanford Site waste tank 241-SY-101 at concentrations above the flammable limit. A large mixer pump installed in the tank in 1993 has effectively mitigated this problem by continuously releasing small amounts of the flammable gases at the rate they are generated. Tank 241-SY-101 is also equipped with multiple high-sensitivity gas monitoring systems and level detection systems to measure the quantity of gas that is retained in and released from the waste

  15. H2S release rate assessment guidelines and audit forms

    International Nuclear Information System (INIS)

    Johnson, S.; Wilson, T.; Long, R.; Shewan, K.; Nchkalo, H.; Nelson, R.; Morand, M.

    1998-01-01

    Development of a process to evaluate and calculate potential hydrogen sulfide release has been recommended by the Canadian Association of Petroleum Producers' Drilling and Completion Committee, and the Alberta Energy and Utilities Board. To facilitate the process, CAPP has released guidelines describing a methodology and standard for the industry to calculate the potential hydrogen sulfide release rates of a well, and a standardized format for the documentation and retention of data. The Guidelines describe a four-step process, with each step having an increasing degree of complexity. Step One describes the zone hydrogen sulfide exclusion area maps, defining when reporting is to be used (based on well location and distance from inhabited areas). Step Two provides details of the recommended method for determining hydrogen sulfide release through a data search process. Step Three consists of a series of instructions in the use of geologic analogs, data editing and wellbore design to further refine the cumulative hydrogen sulfide release rate. Step Four contains information designed to assist in detailed geological and reservoir modeling. It is not necessary to use all four steps in all cases. The user, however, is advised to use sound engineering judgement and due diligence in the calculation decisions. Sample calculations are provided for a variety of different situations. Measurement techniques are described in an appendix. A completed example of an audit form is attached. 10 + 6 refs., tabs

  16. Safety assessment for proposed pump mixing operations to mitigate episodic gas releases in tank 241-101-SY: Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Lentsch, J.W., Westinghouse Hanford

    1996-05-16

    This safety assessment addresses each of the elements required for the proposed action to remove a slurry distributor and to install, operate, and remove a mixing pump in Tank 241-SY-101, which is located within the Hanford Site, Richland, Washington. The proposed action is required as part of an ongoing evaluation of various mitigation concepts developed to eliminate episodic gas releases that result in hydrogen concentrations in the tank dome space that exceed the lower flammability limit.

  17. Release rate of diazinon from microcapsule based on melamine formaldehyde

    Science.gov (United States)

    Noviana Utami C., S.; Rochmadi

    2018-04-01

    The microcapsule containing diazinon as the core material and melamine formaldehyde as the membrane material have been synthesized by in situ polymerization method. The microcapsule membrane in this research is melamine formaldehyde (MF). This research aims to study the effect of pH and temperature on the release rate of diazinon from microcapsule based on melamine formaldehyde in aqueous medium. The results showed that pH and temperature has little effect on the release rate of diazinon from microcapsule based on melamine formaldehyde. This is due to the diffusion through the microcapsule membrane is not influenced by the pH and temperature of the solution outside of microcapsule.

  18. Mechanical pumping at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Perin, J.P.; Claudet, G.; Disdier, F.

    1994-12-31

    This new concept consists of a mechanical pump able to run at low temperature (25 K). Since gas density varies inversely with temperature, the pump could deliver much higher mass flow rate than at room temperature for a given size. Advantages of this concept are reduction of an order of magnitude in size and weight when compared to a conventional pump scaled to perform the same mass flow rate at room temperature. Results obtained at 80 K and 25 K with a Holweck type molecular drag pump of 100 mm diameter and with few stages of a turbomolecular pump running at the same temperatures, are given. This pump would be a solution to allow continuous tritium extraction and minimize the mass inventory for the ITER (International Tokamak Experiment Reactor). 5 figs., 2 tabs., 4 refs.

  19. An analytical method for defining the pump`s power optimum of a water-to-water heat pump heating system using COP

    Directory of Open Access Journals (Sweden)

    Nyers Jozsef

    2017-01-01

    Full Text Available This paper analyzes the energy efficiency of the heat pump and the complete heat pump heating system. Essentially, the maximum of the coefficient of performance of the heat pump and the heat pump heating system are investigated and determined by applying a new analytical optimization procedure. The analyzed physical system consists of the water-to-water heat pump, circulation and well pump. In the analytical optimization procedure the "first derivative equal to zero" mathematical method is applied. The objective function is the coefficient of performance of the heat pump, and the heat pump heating system. By using the analytical optimization procedure and the objective function, as the result, the local and the total energy optimum conditions with respect to the mass flow rate of hot and cold water i. e. the power of circulation or well pump are defined.

  20. Progression of scoliosis in patients with spastic quadriplegia after the insertion of an intrathecal baclofen pump.

    Science.gov (United States)

    Ginsburg, Glen M; Lauder, Anthony J

    2007-11-15

    Medical and radiographic review of 19 consecutive patients with spastic quadriplegia before and after intrathecal baclofen pump insertion with special attention paid to progression of scoliosis. Many orthopedic surgeons who treat spastic quadriplegic patients have noticed a trend of marked scoliosis progression after the administration of intrathecal baclofen (ITB) via subcutaneous pump and catheter. The purpose of this study is to quantify scoliosis progression in this patient population before and after baclofen administration and compare this to published natural history data. The authors had noted rapid progression of scoliosis in spastic quadriplegic patients after intrathecal baclofen pump insertion. This had been noted at other centers, but no significant statistical analysis had been done comparing prepump to postpump scoliosis progression in these patients. To document the magnitude and rate of scoliosis progressions after the placement of an ITB pump, the charts and radiographs of 19 consecutive nonambulatory patients with spastic quadriplegia and an ITB pump were reviewed. To document the rate of scoliosis progression, each patient had at least 2 pre and 2 postpump insertion spinal radiographs made. All radiographs were made with the patients in the supine position without orthoses. A board-certified orthopedic surgeon reviewed these radiographs. Skeletal maturity was assessed using Risser grading. Catheter tip location and rate of baclofen administration were recorded. For 19 patients with complete radiographic data, average Cobb angles were 10.2 degrees before pump insertion and 25 degrees at an average of 20.9 months after pump insertion (P quadriplegia and ITB pump. The authors are now performing spinal fusions for curves that exceed 40 degrees to 50 degrees in the presence of an ITB pump as recommended by previous reviews of scoliosis and accompanying quadriplegia.

  1. Comparison of different insulin pump makes under routine care conditions in adults with Type 1 diabetes.

    Science.gov (United States)

    Leelarathna, L; Roberts, S A; Hindle, A; Markakis, K; Alam, T; Chapman, A; Morris, J; Urwin, A; Jinadev, P; Rutter, M K

    2017-10-01

    To compare long-term HbA 1c changes associated with different insulin pumps during routine care in a large cohort of adults with Type 1 diabetes representative of other clinic populations. Observational, retrospective study of 508 individuals starting pump therapy between 1999 and 2014 (mean age, 40 years; 55% women; diabetes duration, 20 years; 94% Type 1 diabetes; median follow-up, 3.7 years). Mixed linear models compared covariate-adjusted HbA 1c changes associated with different pump makes. The pumps compared were: 50% Medtronic, 24% Omnipod, 14% Roche and 12% Animas. Overall HbA 1c levels improved and improvements were maintained during a follow-up extending to 10 years (HbA 1c : pre-continuous subcutaneous insulin infusion (pre-CSII) vs. 12 months post CSII, 71 (61, 82) vs. 66 (56, 74) mmol/mol; 8.7 (7.7, 9.6) vs. 8.2 (7.3, 8.9)%; P < 0.0001). The percentage of individuals with HbA 1c ≥ 64 mmol/mol (8.0%) reduced from a pre-CSII level of 68% to 55%. After adjusting for baseline confounders, there were no between-pump differences in HbA 1c lowering (P = 0.44), including a comparison of patch pumps with traditional catheter pumps (P = 0.63). There were no significant (P < 0.05) between-pump differences in HbA 1c lowering in pre-specified subgroups stratified by pre-pump HbA 1c , age or diabetes duration. HbA 1c lowering was positively related to baseline HbA 1c (P < 0.001) and diabetes duration (P = 0.017), and negatively related to the number of years of CSII use (P = 0.024). Under routine care conditions, there were no covariate-adjusted differences in HbA 1c lowering when comparing different pump makes, including a comparison of patch pumps vs. traditional catheter pumps. Therefore, the choice of CSII make should not be influenced by the desired degree of HbA 1c lowering. © 2017 Diabetes UK.

  2. A review on controlled porosity osmotic pump tablets and its evaluation

    Directory of Open Access Journals (Sweden)

    Chinmaya Keshari Sahoo

    2015-12-01

    Full Text Available Conventional drug delivery system provides an immediate release of drug which does not control the release of the drug and does not maintain effective concentration at target site for a longer period of time. Hence to avoid the shortcomings there is development of various controlled drug delivery systems. Among these osmotic drug delivery system (ODDS utilizes the principle of osmotic pressure and delivers drug dose in an optimized manner to maintain drug concentration within the therapeutic window and minimizes toxic effects. ODDS releases drug at a controlled rate that is independent of the pH and thermodynamics of dissolution medium. The release of drug from ODDS follows zero order kinetics. The release of drug from osmotic system depends upon various formulation factors such as solubility, osmotic pressure of the core components, size of the delivery orifice and nature of the rate controlling membrane. Controlled porosity osmotic pump (CPOP contains drug, osmogens, excipients in core and a coating of semipermeable membrane with water soluble additives. In CPOP water soluble additives dissolve after coming in contact with water, resulting in an in situ formation of a microporous membrane. The present study gives an idea about osmosis, CPOP, components of CPOP and its evaluation.

  3. Effect of Nisin's Controlled Release on Microbial Growth as Modeled for Micrococcus luteus.

    Science.gov (United States)

    Balasubramanian, Aishwarya; Lee, Dong Sun; Chikindas, Michael L; Yam, Kit L

    2011-06-01

    The need for safe food products has motivated food scientists and industry to find novel technologies for antimicrobial delivery for improving food safety and quality. Controlled release packaging is a novel technology that uses the package to deliver antimicrobials in a controlled manner and sustain antimicrobial stress on the targeted microorganism over the required shelf life. This work studied the effect of controlled release of nisin to inhibit growth of Micrococcus luteus (a model microorganism) using a computerized syringe pump system to mimic the release of nisin from packaging films which was characterized by an initially fast rate and a slower rate as time progressed. The results show that controlled release of nisin was strikingly more effective than instantly added ("formulated") nisin. While instant addition experiments achieved microbial inhibition only at the beginning, controlled release experiments achieved complete microbial inhibition for a longer time, even when as little as 15% of the amount of nisin was used as compared to instant addition.

  4. The burning and smoke release rates of sodium pool fires

    International Nuclear Information System (INIS)

    Newman, R.N.; Payne, J.F.B.

    1976-10-01

    The burning rates and smoke release fractions of sodium pool fires have been measured over the pool temperature range 250 0 C to 750 0 C. A theoretical model is derived which satisfactorily predicts the burning rate over the above temperature range. The theory further predicts that the burning rate should be independent of pool diameter, a prediction supported by a comparison of burning rate data from this study and available data from other studies. (author)

  5. Mitigation of tank 241-SY-101 by pump mixing: Results of full-scale testing

    International Nuclear Information System (INIS)

    Stewart, C.W.; Hudson, J.D.; Friley, J.R.; Panisko, F.E.; Antoniak, Z.I.; Irwin, J.J.; Fadeff, J.G.; Efferding, L.F.; Michener, T.E.; Kirch, N.W.

    1994-06-01

    The Full-Scale Mixer Pump Test Program was performed in Hanford Tank 241-SY-101 from February 4 to April 13, 1994, to confirm the long-term operational strategy for flammable gas mitigation and to demonstrate that mixing can control the gas release and waste level. Since its installation on July 3, 1993, the current pump, operating only a few hours per week, has proved capable of mixing the waste sufficiently to release gas continuously instead of in large episodic events. The results of Full-Scale Testing demonstrated that the pump can control gas release and waste level for long-term mitigation, and the four test sequences formed the basis for the long-term operating schedule. The last test sequence, jet penetration tests, showed that the current pump jet creates flow near the tank wall and that it can excavate portions of the bottom sludge layer if run at maximum power. Pump mixing has altered the open-quote normal close-quote configuration of the waste; most of the original nonconvective sludge has been mixed with the supernatant liquid into a mobile convective slurry that has since been maintained by gentle pump operation and does not readily return to sludge

  6. A safety assessment for proposed pump mixing operations to mitigate episodic gas releases in tank 241-SY-101: Hanford Site,Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Lentsch, J.W.

    1996-07-01

    This safety assessment addresses each of the elements required for the proposed action to remove a slurry distributor and to install, operate, and remove a mixing pump in Tank 241-SY-101,which is located within the Hanford Site, Richland, Washington.The proposed action is required as part of an ongoing evaluation of various mitigation concepts developed to eliminate episodic gas releases that result in hydrogen concentrations in the tank dome space that exceed the lower flammability limit.

  7. Reactor feedwater pump control device

    International Nuclear Information System (INIS)

    Nishiyama, Hiroyuki.

    1990-01-01

    An amount of feedwater necessary for ensuring reactor inventory after scram is ensured automatically based on the reactor output before scram of a BWR type reactor. That is, if scram should occur, a feedwater flow rate just before the scram is stored by reactor output signals. Further, the amount of feedwater required after the scram is determined based on the output of the memory. The reactor power after the scram based on a feedwater flow rate and a main steam flow rate is inputted to an integrator, to calculate and output the amount of the feedwater flow rate (1) injected after the scram for the inventory. A coast down flowrate (2) in a case of pump trip is forecast by the output signals. Automatic trip is outputted to all turbine driving feedwater pumps when the sum of (1) and (2) exceeds a necessary and sufficient amount of feedwater required for ensuring inventory. For motor driving feedwater pumps, only a portion, for example, one of the pumps is automatically started while other pumps are stopped their operation, only in this case, to prevent excess water feeding. (I.S.)

  8. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  9. Experimental characterization of true spontaneous emission rate of optically-pumped InGaAs/GaAs quantum-well laser structure

    Directory of Open Access Journals (Sweden)

    Q.-N. Yu

    2017-08-01

    Full Text Available In this paper, an experimental approach to acquiring true spontaneous emission rate of optically-pumped InGaAs/GaAs quantum-well laser structure is described. This method is based on a single edge-emitting laser chip with simple sample processing. The photoluminescence spectra are measured at both facets of the edge-emitting device and transformed to the spontaneous emission rate following the theory described here. The unusual double peaks appearing in the spontaneous emission rate spectra are observed for the InGaAs/GaAs quantum-well structure. The result is analyzed in terms of Indium-rich island and Model-Solid theories. The proposed method is suitable for electrically-pumped quantum-well laser structures, as well.

  10. Radionuclide release rates from spent fuel for performance assessment modeling

    International Nuclear Information System (INIS)

    Curtis, D.B.

    1994-01-01

    In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different approach to obtaining a numerical measure and each has its limitations. There is no way to obtain an unambiguous measure of this or any parameter used in performance assessment codes for evaluating the effects of processes operative over many millennia. The examples are intended to suggest by example that in the absence of the ability to evaluate accuracy and precision, consistency of a broadly based set of data can be used as circumstantial evidence to defend the choice of parameters used in performance assessments

  11. Pumps in wearable ultrafiltration devices: pumps in wuf devices.

    Science.gov (United States)

    Armignacco, Paolo; Garzotto, Francesco; Bellini, Corrado; Neri, Mauro; Lorenzin, Anna; Sartori, Marco; Ronco, Claudio

    2015-01-01

    The wearable artificial kidney (WAK) is a device that is supposed to operate like a real kidney, which permits prolonged, frequent, and continuous dialysis treatments for patients with end-stage renal disease (ESRD). Its functioning is mainly related to its pumping system, as well as to its dialysate-generating and alarm/shutoff ones. A pump is defined as a device that moves fluids by mechanical action. In such a context, blood pumps pull blood from the access side of the dialysis catheter and return the blood at the same rate of flow. The main aim of this paper is to review the current literature on blood pumps, describing the way they have been functioning thus far and how they are being engineered, giving details about the most important parameters that define their quality, thus allowing the production of a radar comparative graph, and listing ideal pumps' features. © 2015 S. Karger AG, Basel.

  12. Diagnosis of Centrifugal Pump Faults Using Vibration Methods

    International Nuclear Information System (INIS)

    Albraik, A; Althobiani, F; Gu, F; Ball, A

    2012-01-01

    Pumps are the largest single consumer of power in industry. This means that faulty pumps cause a high rate of energy loss with associated performance degradation, high vibration levels and significant noise radiation. This paper investigates the correlations between pump performance parameters including head, flow rate and energy consumption and surface vibration for the purpose of both pump condition monitoring and performance assessment. Using an in-house pump system, a number of experiments have been carried out on a centrifugal pump system using five impellers: one in good condition and four others with different defects, and at different flow rates for the comparison purposes. The results have shown that each defective impeller performance curve (showing flow, head, efficiency and NPSH (Net Positive Suction Head) is different from the benchmark curve showing the performance of the impeller in good condition. The exterior vibration responses were investigated to extract several key features to represent the healthy pump condition, pump operating condition and pump energy consumption. In combination, these parameter allow an optimal decision for pump overhaul to be made.

  13. Diagnosis of Centrifugal Pump Faults Using Vibration Methods

    Science.gov (United States)

    Albraik, A.; Althobiani, F.; Gu, F.; Ball, A.

    2012-05-01

    Pumps are the largest single consumer of power in industry. This means that faulty pumps cause a high rate of energy loss with associated performance degradation, high vibration levels and significant noise radiation. This paper investigates the correlations between pump performance parameters including head, flow rate and energy consumption and surface vibration for the purpose of both pump condition monitoring and performance assessment. Using an in-house pump system, a number of experiments have been carried out on a centrifugal pump system using five impellers: one in good condition and four others with different defects, and at different flow rates for the comparison purposes. The results have shown that each defective impeller performance curve (showing flow, head, efficiency and NPSH (Net Positive Suction Head) is different from the benchmark curve showing the performance of the impeller in good condition. The exterior vibration responses were investigated to extract several key features to represent the healthy pump condition, pump operating condition and pump energy consumption. In combination, these parameter allow an optimal decision for pump overhaul to be made [1].

  14. Method for pre-heating lmfbr type reactors

    International Nuclear Information System (INIS)

    Yokozawa, Atsushi; Kataoka, Hajime.

    1978-01-01

    Purpose: To enable pre-heating for the inside of the reactor container and the inside of the coolant recycling system with no additional facilities. Method: The coolant recycling system is composed of a heat exchanger, a mechanical pump, a check valve, a flow meter or the like and it is connected in series by way of a pipe line to a reactor container. The mechanical pump is used as a gas recycling device upon pre-heating and it is designed so that a blower such as a fan can be replaced for the impeller of the pump. The inside of the reactor container and the inside of the coolant recycling system is at first filled with an inert gas such as for use with cover gas. Then, nuclear fuels are loaded to attain criticality. Simultaneously, the blower is started and the control rods are operated while cooling the nuclear fuel with the inert gas thus to obtain heat required for pre-heating the pipe line or the like from the nuclear fuels. After the completion of the pre-heating, the liquid metal is charged. (Ikeda, J.)

  15. Tritium breeding and release-rate kinetics from neutron-irradiated lithium oxide

    International Nuclear Information System (INIS)

    Quanci, J.F.

    1989-01-01

    The research encompasses the measurement of the tritium breeding and release-rate kinetics from lithium oxide, a ceramic tritium-breeding material. A thermal extraction apparatus which allows the accurate measurement of the total tritium inventory and release rate from lithium oxide samples under different temperatures, pressures and carrier-gas compositions with an uncertainty not exceeding 3% was developed. The goal of the Lithium Blanket Module program was to determine if advanced computer codes could accurately predict the tritium production in the lithium oxide blanket of a fusion power plant. A fusion blanket module prototype was built and irradiated with a deuterium-tritium fusion-neutron source. The tritium production throughout the module was modeled with the MCNP three dimensional Monte Carlo code and was compared to the assay of the tritium bred in the module. The MCNP code accurately predicted tritium-breeding trends but underestimated the overall tritium breeding by 30%. The release rate of tritium from small grain polycrystalline sintered lithium oxides with a helium carrier gas from 300 to 450 C was found to be controlled by the first order surface desorption of monotritiated water. When small amounts of hydrogen were added to the helium carrier gas, the first order rate constant increased from the isotopic exchange of hydrogen for tritium at the lithium oxide surface occurring in parallel with the first order desorption process. The isotopic-exchange first order rate constant temperature dependence and hydrogen partial pressure dependence were evaluated

  16. A microfluidic timer for timed valving and pumping in centrifugal microfluidics.

    Science.gov (United States)

    Schwemmer, F; Zehnle, S; Mark, D; von Stetten, F; Zengerle, R; Paust, N

    2015-03-21

    Accurate timing of microfluidic operations is essential for the automation of complex laboratory workflows, in particular for the supply of sample and reagents. Here we present a new unit operation for timed valving and pumping in centrifugal microfluidics. It is based on temporary storage of pneumatic energy and time delayed sudden release of said energy. The timer is loaded at a relatively higher spinning frequency. The countdown is started by reducing to a relatively lower release frequency, at which the timer is released after a pre-defined delay time. We demonstrate timing for 1) the sequential release of 4 liquids at times of 2.7 s ± 0.2 s, 14.0 s ± 0.5 s, 43.4 s ± 1.0 s and 133.8 s ± 2.3 s, 2) timed valving of typical assay reagents (contact angles 36-78°, viscosities 0.9-5.6 mPa s) and 3) on demand valving of liquids from 4 inlet chambers in any user defined sequence controlled by the spinning protocol. The microfluidic timer is compatible to all wetting properties and viscosities of common assay reagents and does neither require assistive equipment, nor coatings. It can be monolithically integrated into a microfluidic test carrier and is compatible to scalable fabrication technologies such as thermoforming or injection molding.

  17. Centrifugal Pump Monitoring and Determination of Pump Characteristic Curves Using Experimental and Analytical Solutions

    Directory of Open Access Journals (Sweden)

    Marius Stan

    2018-02-01

    Full Text Available Centrifugal pumps are widely used in the industry, especially in the oil and gas sector for fluids transport. Classically, these are designed to transfer single phase fluids (e.g., water at high flow rates and relatively low pressures when compared with other pump types. As part of their constructive feature, centrifugal pumps rely on seals to prevent air entrapment into the rotor during its normal operation. Although this is a constructive feature, water should pass through the pump inlet even when the inlet manifold is damaged. Modern pumps are integrated in pumping units which consist of a drive (normally electric motor, a transmission (when needed, an electronic package (for monitoring and control, and the pump itself. The unit also has intake and outlet manifolds equipped with valves. Modern systems also include electronic components to measure and monitor pump working parameters such as pressure, temperature, etc. Equipment monitoring devices (vibration sensors, microphones are installed on modern pumping units to help users evaluate the state of the machinery and detect deviations from the normal working condition. This paper addresses the influence of air-water two-phase mixture on the characteristic curve of a centrifugal pump; pump vibration in operation at various flow rates under these conditions; the possibilities of using the results of experimental investigations in the numerical simulations for design and training purposes, and the possibility of using vibration and sound analysis to detect changes in the equipment working condition. Conclusions show that vibration analysis provides accurate information about the pump’s functional state and the pumping process. Moreover, the acoustic emission also enables the evaluation of the pump status, but needs further improvements to better capture and isolate the usable sounds from the environment.

  18. Reactor coolant purification system circulation pumps (CUW pumps)

    International Nuclear Information System (INIS)

    Tsutsui, Toshiaki

    1979-01-01

    Coolant purification equipments for BWRs have been improved, and the high pressure purifying system has become the main type. The quantity of purifying treatment also changed to 2% of the flow rate of reactor feed water. As for the circulation pumps, canned motor pumps are adopted recently, and the improvements of reliability and safety are attempted. The impurities carried in by reactor feed water and the corrosion products generated in reactors and auxiliary equipments are activated by neutron irradiation or affect heat transfer adversely, adhering to fuel claddings are core structures. Therefore, a part of reactor coolant is led to the purification equipments, and returned to reactors after the impurities are eliminated perfectly. At the time of starting and stopping reactors, excess reactor water and the contaminated water from reactors are transferred to main condenser hot wells or waste treatment systems. Thus the prescribed water quality is maintained. The operational modes of and the requirements for the CUW pumps, the construction and the features of the canned motor type CUW pumps are explained. Recently, a pump operated for 11 months without any maintenance has been disassembled and inspected, but the wear of bearings has not been observed, and the high reliability of the pump has been proved. (Kako, I.)

  19. Treatment of idiopathic hypogonadotropic hypogonadism in men with luteinizing hormone-releasing hormone: a comparison of treatment with daily injections and with the pulsatile infusion pump.

    Science.gov (United States)

    Shargil, A A

    1987-03-01

    Thirty husbands in childless couples, aged 24 to 35 years, were treated with luteinizing hormone-releasing hormone (LH-RH) for idiopathic hypogonadotropic hypogonadism (IHH) of peripubertal (incomplete) type. They were azoospermic or oligospermic, with less than 1.5 X 10(6)/ml nonmotile spermatozoa. The diagnosis of IHH was based on clinical and laboratory features and testicular biopsy specimen study and was further supported by results of stimulation tests and gonadotropin-releasing hormone (GnRH) test. Two treatment modalities were used: subcutaneous injections of 500 micrograms LH-RH twice daily; and perpetual subcutaneous injection, via portable infusion pump, of 25 ng/kg LH-RH, at 90-minute intervals. Two patients required a short second period of pulsatile treatment to cause a second pregnancy of their spouses. The pump proved to yield better results, compared with intermittent injections, in respect to endocrine responses, spermatogenesis, and fertility capacity. Normal levels of luteinizing hormone and follicle-stimulating hormone were reached in 2 to 3 weeks and normal testosterone levels in 8 to 10 weeks from the start of treatment. Sperm counts rose to greater than 60 X 10(6)/ml viable spermatozoa with less than 15% of abnormal forms in 3 to 5 months, and the wives conceived. Of a total of 18 deliveries of healthy infants, 12 offspring were identified genetically with their fathers. Four women were still pregnant at the conclusion of the study. The pump was well tolerated, without special operational problems to the patients. Pulsatile treatment is therefore recommended in the treatment of well-diagnosed and carefully selected cases of incomplete IHH.

  20. Hydraulic optimization of 'S' characteristics of the pump-turbine for Xianju pumped storage plant

    International Nuclear Information System (INIS)

    Liu, W C; Zheng, J S; Cheng, J; Shi, Q H

    2012-01-01

    The pump-turbine with a rated power capacity of 375MW each at Xianju pumped storage plant is the most powerful one under construction in China. In order to avoid the instability near no-load conditions, the hydraulic design of the pump-turbine has been optimized to improving the 'S' characteristic in the development of the model pump-turbine. This paper presents the cause of 'S' characteristic of a pump-turbine by CFD simulation of the internal flow. Based on the CFD analysis, the hydraulic design optimization of the pump-turbine was carried out to eliminate the 'S' characteristics of the machine at Xianju pumped storage plant and a big step for removing the 'S' characteristic of a pump-turbine has been obtained. The model test results demonstrate that the pump-turbine designed for Xianju pumped storage plant can smoothly operate near no-load conditions without an addition of misaligned guide vanes.

  1. Efficiency of the pre-heater against flow rate on primary the beta test loop

    International Nuclear Information System (INIS)

    Edy Sumarno; Kiswanta; Bambang Heru; Ainur R; Joko P

    2013-01-01

    Calculation of efficiency of the pre-heater has been carried out against the flow rate on primary the BETA Test Loop. BETA test loop (UUB) is a facilities of experiments to study the thermal hydraulic phenomenon, especially for thermal hydraulic post-LOCA (Lost of Coolant Accident). Sequences removal on the BETA Test Loop contained a pre-heater that serves as a getter heat from the primary side to the secondary side, determination of efficiency is to compare the incoming heat energy with the energy taken out by a secondary fluid. Characterization is intended to determine the performance of a pre-heater, then used as tool for analysis, and as a reference design experiments. Calculation of efficiency methods performed by operating the pre-heater with fluid flow rate variation on the primary side. Calculation of efficiency on the results obtained that the efficiency change with every change of flow rate, the flow rate is 71.26% on 163.50 ml/s and 60.65% on 850.90 ml/s. Efficiency value can be even greater if the pre-heater tank is wrapped with thermal insulation so there is no heat leakage. (author)

  2. Radionuclide release rate inversion of nuclear accidents in nuclear facility based on Kalman filter

    International Nuclear Information System (INIS)

    Tang Xiuhuan; Bao Lihong; Li Hua; Wan Junsheng

    2014-01-01

    The rapidly and continually back-calculating source term is important for nuclear emergency response. The Gaussian multi-puff atmospheric dispersion model was used to produce regional environment monitoring data virtually, and then a Kalman filter was designed to inverse radionuclide release rate of nuclear accidents in nuclear facility and the release rate tracking in real time was achieved. The results show that the Kalman filter combined with Gaussian multi-puff atmospheric dispersion model can successfully track the virtually stable, linear or nonlinear release rate after being iterated about 10 times. The standard error of inversion results increases with the true value. Meanwhile extended Kalman filter cannot inverse the height parameter of accident release as interceptive error is too large to converge. Kalman filter constructed from environment monitoring data and Gaussian multi-puff atmospheric dispersion model can be applied to source inversion in nuclear accident which is characterized by static height and position, short and continual release in nuclear facility. Hence it turns out to be an alternative source inversion method in nuclear emergency response. (authors)

  3. High-vacuum pumping out of hydrogen isotopes by compressed and electrophysical pumps

    International Nuclear Information System (INIS)

    Bychkova, A.D.; Ershova, Z.V.; Saksaganskij, G.L.; Serebrennikov, D.V.

    1982-01-01

    To explain the selection of parameters of vacuum systems of projected thermonuclear devices, experiments are performed on the pumping-out of deuterium and tritium by high-vacuum pumps of different types. The values of the fast response of turbomolecular, diffusion vapour-mercury, magneto-discharge and titanium getter pumps in the operation pressure range are determined. The rate of sorption of hydrogen isotopes by non-spraying gas absorber of cial alloy depending on the amount of the gas absorbed and temperature, is measured. Gas current is determined by the pressure drop on the diagram of the known conductivity. Individual calibration of manometric converters for different gases using a mercury burette is performed preliminarily. The means of high-vacuum pumping-out that have been studied have the following values of fast response for tritium (relatively to protium): turbomolecular pump-0.95; evaporation getter pump-0.25; magneto-discharge pumps-0.65-0.9; cial alloy-0.1...0.5

  4. Test of a cryogenic helium pump

    International Nuclear Information System (INIS)

    Lue, J.W.; Miller, J.R.; Walstrom, P.L.; Herz, W.

    1981-01-01

    The design of a cryogenic helium pump for circulating liquid helium in a magnet and the design of a test loop for measuring the pump performance in terms of mass flow vs pump head at various pump speeds are described. A commercial cryogenic helium pump was tested successfully. Despite flaws in the demountable connections, the piston pump itself has performed satisfactorily. A helium pump of this type is suitable for the use of flowing supercritical helium through Internally Cooled Superconductor (ICS) magnets. It has pumped supercritical helium up to 7.5 atm with a pump head up to 2.8 atm. The maximum mass flow rate obtained was about 16 g/s. Performance of the pump was degraded at lower pumping speeds

  5. Pre-irradiation at a low dose-rate blunted p53 response

    International Nuclear Information System (INIS)

    Takahashi, A.; Ohnishi, K.; Asakawa, I.; Tamamoto, T.; Yasumoto, J.; Yuki, K.; Ohnishi, T.; Tachibana, A.

    2003-01-01

    Full text: We have studied whether the p53-centered signal transduction pathway induced by acute radiation is interfered with chronic pre-irradiation at a low dose-rate in human cultured cells and whole body of mice. In squamous cell carcinoma cells, we found that a challenge irradiation with X-ray immediately after chronic irradiation resulted in lower levels of p53 than those observed after the challenge irradiation alone. In addition, the induction of p53-centered apoptosis and the accumulation of its related proteins after the challenge irradiation were strongly correlated with the above-mentioned phenomena. In mouse spleen, the induction of apoptosis and the accumulation of p53 and Bax were observed dose-dependently at 12 h after a challenge irradiation. In contrast, we found significant suppression of them induced by challenge irradiation at a high dose-rate when mice were pre-irradiated with chronic irradiation at a low dose-rate. These findings suggest that chronic pre-irradiation suppressed the p53 function through radiation-induced p53-dependent signal transduction processes. There are numerous papers about p53 functions in apoptosis, radiosensitivity, genomic instability and cancer incidence in cultured cells or animals. According to our data and other findings, since p53 can prevent carcinogenesis, pre-irradiation at a low dose-rate might enhance the predisposition to cancer. Therefore, it is possible that different maximal permissible dose equivalents for the public populations are appropriate. Furthermore, concerning health of human beings, studies of the adaptive responses to radiation are quite important, because the radiation response strongly depends on experience of prior exposure to radiation

  6. A mathematical model for LH release in response to continuous and pulsatile exposure of gonadotrophs to GnRH

    Directory of Open Access Journals (Sweden)

    Reed Michael C

    2004-09-01

    Full Text Available Abstract In a previous study, a model was developed to investigate the release of luteinizing hormone (LH from pituitary cells in response to a short pulse of gonadotropin-releasing hormone (GnRH. The model included: binding of GnRH to its receptor (R, dimerization and internalization of the hormone receptor complex, interaction with a G protein, production of inositol 1,4,5-trisphosphate (IP3, release of calcium from the endoplasmic reticulum (ER, entrance of calcium into the cytosol via voltage gated membrane channels, pumping of calcium out of the cytosol via membrane and ER pumps, and release of LH. The extended model, presented in this paper, also includes the following physiologically important phenomena: desensitization of calcium channels; internalization of the dimerized receptors and recycling of some of the internalized receptors; an increase in Gq concentration near the plasma membrane in response to receptor dimerization; and basal rates of synthesis and degradation of the receptors. With suitable choices of the parameters, good agreement with a variety of experimental data of the LH release pattern in response to pulses of various durations, repetition rates, and concentrations of GnRH were obtained. The mathematical model allows us to assess the effects of internalization and desensitization on the shapes and time courses of LH response curves.

  7. Electroosmotic pumps for microflow analysis

    Science.gov (United States)

    Wang, Xiayan; Wang, Shili; Gendhar, Brina; Cheng, Chang; Byun, Chang Kyu; Li, Guanbin; Zhao, Meiping; Liu, Shaorong

    2009-01-01

    With rapid development in microflow analysis, electroosmotic pumps are receiving increasing attention. Compared to other micropumps, electroosmotic pumps have several unique features. For example, they are bi-directional, can generate constant and pulse-free flows with flow rates well suited to microanalytical systems, and can be readily integrated with lab-on-chip devices. The magnitude and the direction of flow of an electroosmotic pump can be changed instantly. In addition, electroosmotic pumps have no moving parts. In this article, we discuss common features, introduce fabrication technologies and highlight applications of electroosmotic pumps. PMID:20047021

  8. Pump--probe measurements of state-to-state rotational energy transfer rates in N2 (v=1)

    International Nuclear Information System (INIS)

    Sitz, G.O.; Farrow, R.L.

    1990-01-01

    We report direct measurements of the state-to-state rotational energy transfer rates for N 2 (υ=1) at 298 K. Stimulated Raman pumping of Q-branch (υ=1 left-arrow 0) transitions is used to prepare a selected rotational state of N 2 in the υ=1 state. After allowing an appropriate time interval for collisions to occur, 2+2 resonance-enhanced multiphoton ionization is used (through the a 1 Π g left-arrow X 1 Σ + g transition) to detect the relative population of the pumped level and other levels to which rotational energy transfer has occurred. We have performed a series of measurements in which a single even rotational level (J i =0--14) is excited and the time-dependent level populations are recorded at three or more delay times. This data set is then globally fit to determine the best set of state-to-state rate constants. The fitting procedure does not place any constraints (such as an exponential gap law) on the J or energy dependence of the rates. We compare our measurements and best-fit rates with results predicted from phenomenological rate models and from a semiclassical scattering calculation of Koszykowski et al. [J. Phys. Chem. 91, 41 (1987)]. Excellent agreement is obtained with two of the models and with the scattering calculation. We also test the validity of the energy-corrected sudden (ECS) scaling theory for N 2 by using our experimental transfer rates as basis rates (J=L→0), finding that the ECS scaling expressions accurately predict the remaining rates

  9. The properties of an improvised piston pump for the rapid delivery of intravenous fluids.

    Science.gov (United States)

    Smart, C M; Primrose, C W; Peters, A L; Speirits, E J

    2014-02-01

    To maximise the effect of a small fluid load, it is occasionally desirable to bolus manually with multiple depressions of a large-capacity syringe. This is usually achieved by placing the syringe on the side port of a three-way tap. We modified this technique by placing two-one-way valves in line with the three-way tap, effectively creating a piston pump, the infusion rates via which we compared with those achieved by an inflatable pressure-infuser in a simulated resuscitation. Fluid flow was faster using the piston pump than with the pressure-infuser (mean (SD) time to infuse 2000 ml saline 0.9% via a 16-G cannula 352 (10) s vs 495 (19) s, respectively, p piston pump appears to have potential for both tight control of fluid delivery and major high-volume resuscitation. The lightweight nature of the pump and its lack of reliance on gravity may also make it suitable for the pre-hospital setting. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  10. Sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of advective release from waste packages under dripping fractures

    International Nuclear Information System (INIS)

    Lee, J.H.; Atkins, J.E.; McNeish, J.A.; Vallikat, V.

    1996-01-01

    Simulations were conducted to analyze the sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of the advective release from waste packages under dripping fractures. The first conceptual model assumed that dripping water directly contacts the waste form inside the 'failed' waste package, and radionuclides are released from the EBS by advection. The second conceptual model assumed that dripping water is diverted around the 'failed' waste package (because of the presence of corrosion products plugging the perforations) and dripping water is prevented from directly contacting the waste form. In the second model, radionuclides were assumed to transport through the perforations by diffusion, and, once outside the waste package, to be released from the EBS by advection. The second model was to incorporate more realism into the EBS release calculations. For the case with the second EBS release model, most radionuclides had significantly lower peak EBS release rates (from at least one to several orders of magnitude) than with the first EBS release model. The impacts of the alternative EBS release models were greater for the radionuclides with a low solubility (or solubility-limited radionuclides) than for the radionuclides with a high solubility (or waste form dissolution-limited radionuclides). The analyses indicated that the EBS release model representing advection through a 'failed' waste package (the first EBS release model) may be too conservative in predicting the EBS performance. One major implication from this sensitivity study was that a 'failed' waste package container with multiple perforations may still be able to perform effectively as an important barrier to radionuclide release. (author)

  11. Electric field-decoupled electroosmotic pump for microfluidic devices.

    Science.gov (United States)

    Liu, Shaorong; Pu, Qiaosheng; Lu, Joann J

    2003-09-26

    An electric field-free electroosmotic pump has been constructed and its pumping rate has been measured under various experimental conditions. The key component of the pump is an ion-exchange membrane grounding joint that serves two major functions: (i) to maintain fluid continuity between pump channels and microfluidic conduit and (ii) to ground the solution in the microfluidic channel at the joint through an external electrode, and hence to decouple the electric field applied to the pump channels from the rest of the microfluidic system. A theoretical model has been developed to calculate the pumping rates and its validity has been demonstrated.

  12. Game theory of pre-emptive vaccination before bioterrorism or accidental release of smallpox.

    Science.gov (United States)

    Molina, Chai; Earn, David J D

    2015-06-06

    Smallpox was eradicated in the 1970s, but new outbreaks could be seeded by bioterrorism or accidental release. Substantial vaccine-induced morbidity and mortality make pre-emptive mass vaccination controversial, and if vaccination is voluntary, then there is a conflict between self- and group interests. This conflict can be framed as a tragedy of the commons, in which herd immunity plays the role of the commons, and free-riding (i.e. not vaccinating pre-emptively) is analogous to exploiting the commons. This game has been analysed previously for a particular post-outbreak vaccination scenario. We consider several post-outbreak vaccination scenarios and compare the expected increase in mortality that results from voluntary versus imposed vaccination. Below a threshold level of post-outbreak vaccination effort, expected mortality is independent of the level of response effort. A lag between an outbreak starting and a response being initiated increases the post-outbreak vaccination effort necessary to reduce mortality. For some post-outbreak vaccination scenarios, even modest response lags make it impractical to reduce mortality by increasing post-outbreak vaccination effort. In such situations, if decreasing the response lag is impossible, the only practical way to reduce mortality is to make the vaccine safer (greater post-outbreak vaccination effort leads only to fewer people vaccinating pre-emptively). © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  13. Improvement of centrifugal pump performance through addition of splitter blades on impeller pump

    Science.gov (United States)

    Kurniawan, Krisna Eka; Santoso, Budi; Tjahjana, Dominicus Danardono Dwi Prija

    2018-02-01

    The workable way to improve pump performance is to redesign or modify the impellers of centrifugal pump. The purpose of impeller pump modification is to improve pump efficiency, reduce cross flow, reduce secondary incidence flows, and decrease backflow areas at impeller outlets. Number blades and splitter blades in the impeller are three. The outlet blade angle is 20°, and the rotating speed of impeller is 2400 rpm. The added splitter blades variations are 0.25, 0.375, and 0.5 of the original blade length. The splitter blade placements are on the outer side of the impeller. The addition of splitter blades on the outer side of the impeller with 0.5L increases the pump head until 22% and the pump has 38.66% hydraulic efficiency. The best efficiency point of water flow rate pump (Qbep) was 3.02 × 10-3 m3/s.

  14. Hanford high level waste (HLW) tank mixer pump safe operating envelope reliability assessment

    International Nuclear Information System (INIS)

    Fischer, S.R.; Clark, J.

    1993-01-01

    The US Department of Energy and its contractor, Westinghouse Corp., are responsible for the management and safe storage of waste accumulated from processing defense reactor irradiated fuels for plutonium recovery at the Hanford Site. These wastes, which consist of liquids and precipitated solids, are stored in underground storage tanks pending final disposition. Currently, 23 waste tanks have been placed on a safety watch list because of their potential for generating, storing, and periodically releasing various quantities of hydrogen and other gases. Tank 101-SY in the Hanford SY Tank Farm has been found to release hydrogen concentrations greater than the lower flammable limit (LFL) during periodic gas release events. In the unlikely event that an ignition source is present during a hydrogen release, a hydrogen burn could occur with a potential to release nuclear waste materials. To mitigate the periodic gas releases occurring from Tank 101-SY, a large mixer pump currently is being installed in the tank to promote a sustained release of hydrogen gas to the tank dome space. An extensive safety analysis (SA) effort was undertaken and documented to ensure the safe operation of the mixer pump after it is installed in Tank 101-SY.1 The SA identified a need for detailed operating, alarm, and abort limits to ensure that analyzed safety limits were not exceeded during pump operations

  15. Calcium release rates from tooth enamel treated with dentifrices containing whitening agents and abrasives.

    Science.gov (United States)

    Araujo, Danilo Barral; Silva, Luciana Rodrigues; de Araujo, Roberto Paulo Correia

    2010-01-01

    Tooth whitening agents containing hydrogen peroxide and carbamide peroxide are used frequently in esthetic dental procedures. However, lesions on the enamel surface have been attributed to the action of these products. Using conventional procedures for separating and isolating biological structures, powdered enamel was obtained and treated with hydrogen peroxide, carbamide peroxide, and sodium bicarbonate, ingredients typically found in dentifrices. The enamel was exposed to different pH levels, and atomic emission spectrometry was used to determine calcium release rates. As the pH level increased, the rate of calcium release from enamel treated with dentifrices containing whitening agents decreased. Carbamide peroxide produced the lowest amount of decalcification, while sodium bicarbonate produced the highest release rates at all pH levels.

  16. Measurement of phytoplankton photosynthesis rate using a pump-and-probe fluorometer

    Directory of Open Access Journals (Sweden)

    Taras K. Antal

    2001-09-01

    Full Text Available In this work we have studied the possibility of determining the rate of phytoplankton photosynthesis in situ using a submersible pump-and-probe fluorometer in water areas differing in their trophic level, as well as in climatic and hydrophysical characteristics. A biophysical model was used to describe the relationship between photosynthesis, underwater irradiance, and the intensity of phytoplankton fluorescence excited by an artificial light source. Fluorescence intensity was used as a measure of light absorption by phytoplankton and for assessing the efficiency of photochemical energy conversion at photosynthetic reaction centers. Parameters of the model that could not be measured experimentally were determined by calibrating fluorescence and irradiance data against the primary production measured in the Baltic Sea with the radioactive carbon method. It was shown that the standard deviation of these parameters in situ did not exceed 20%, and the use of their mean values to estimate the phytoplankton photosynthetic rate showed a good correlation between the calculated and meas

  17. Considerations for reference pump curves

    International Nuclear Information System (INIS)

    Stockton, N.B.

    1992-01-01

    This paper examines problems associated with inservice testing (IST) of pumps to assess their hydraulic performance using reference pump curves to establish acceptance criteria. Safety-related pumps at nuclear power plants are tested under the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (the Code), Section 11. The Code requires testing pumps at specific reference points of differential pressure or flow rate that can be readily duplicated during subsequent tests. There are many cases where test conditions cannot be duplicated. For some pumps, such as service water or component cooling pumps, the flow rate at any time depends on plant conditions and the arrangement of multiple independent and constantly changing loads. System conditions cannot be controlled to duplicate a specific reference value. In these cases, utilities frequently request to use pump curves for comparison of test data for acceptance. There is no prescribed method for developing a pump reference curve. The methods vary and may yield substantially different results. Some results are conservative when compared to the Code requirements; some are not. The errors associated with different curve testing techniques should be understood and controlled within reasonable bounds. Manufacturer's pump curves, in general, are not sufficiently accurate to use as reference pump curves for IST. Testing using reference curves generated with polynomial least squares fits over limited ranges of pump operation, cubic spline interpolation, or cubic spline least squares fits can provide a measure of pump hydraulic performance that is at least as accurate as the Code required method. Regardless of the test method, error can be reduced by using more accurate instruments, by correcting for systematic errors, by increasing the number of data points, and by taking repetitive measurements at each data point

  18. Magnetohydrodynamic generator and pump system

    International Nuclear Information System (INIS)

    Birzvalk, Yu.A.; Karasev, B.G.; Lavrentyev, I.V.; Semikov, G.T.

    1983-01-01

    The MHD generator-pump system, or MHD coupling, is designed to pump liquid-metal coolant in the primary circuit of a fast reactor. It contains a number of generator and pump channels placed one after another and forming a single electrical circuit, but hydraulically connected parallel to the second and first circuits of the reactor. All the generator and pump channels are located in a magnetic field created by the magnetic system with an excitation winding that is fed by a regulated direct current. In 500 to 2000 MW reactors, the flow rate of the coolant in each loop of the primary circuit is 3 to 6 m 3 /s and the hydraulic power is 2 to 4 MW. This paper examines the primary characteristics of an MHD generator-pump system with various dimensions and number of channels, wall thicknesses, coolant flow rates, and magnetic fields. It is shown that its efficiency may reach 60 to 70%. The operating principle of the MHD generator-pump system is explained in the referenced patent and involves the transfer of hydraulic power from generator channels to pump channels using a magnetic field and electrical circuit common to both channels. Variations of this system may be analyzed using an equivalent circuit. 7 refs., 5 figs

  19. Translational and extensional energy release rates (the J- and M-integrals) for a crack layer in thermoelasticity

    Science.gov (United States)

    Chudnovsky, A.; Gommerstadt, B.

    1985-01-01

    A number of papers have been presented on the evaluation of energy release rate for thermoelasticity and corresponding J integral. Two main approaches were developed to treat energy release rate in elasticity. The first is based on direct calculation of the potential energy rate with respect to crack length. The second makes use of Lagrangian formalism. The translational and expansional energy release rates in thermoelasticity are studied by employing the formalism of irreversible thermodynamics and the Crack Layer Approach.

  20. Ultrasound coupled with Fenton oxidation pre-treatment of sludge to release organic carbon, nitrogen and phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Changxiu [School of Environment, Tsinghua University, Beijing 100084 (China); Jiang, Jianguo, E-mail: jianguoj@mail.tsinghua.edu.cn [School of Environment, Tsinghua University, Beijing 100084 (China); Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China (China); Collaborative Innovation Center for Regional Environmental Quality, Tsinghua University, Beijing (China); Li, De' an [School of Environment, Tsinghua University, Beijing 100084 (China)

    2015-11-01

    We focused on the effects of ultrasound and Fenton reagent in ultrasonic coupling Fenton oxidation (U + F) pre-treatment processes on the disintegration of wastewater treatment plant sludge. The results demonstrated that U + F treatment could significantly increase soluble COD, TOC, total N, proteins, total P and PO{sub 4}{sup 3−} concentrations in sludge supernatant. This method was more effective than ultrasonic (U) or Fenton oxidation (F) treatment alone. U + F treatment increased the soluble COD by 2.1- and 1.4-fold compared with U and F alone, respectively. U + F treatment increased the total N and P by 1.7- and 2.2-fold, respectively, compared with F alone. After U + F treatment, sludge showed a considerably finer particle size and looser microstructure based on scanning electron microscopy, and the highest OH· signal intensity increased from 568.7 by F treatment to 1106.3 using electron spin resonance. This demonstrated that U + F treatment induces disintegration of sludge and release of organic carbon, nitrogen and phosphorus better. - Highlights: • Combined ultrasound–Fenton pre-treatment was proposed for sludge disintegration. • Ultrasound–Fenton significantly increased carbon, nitrogen and phosphorus release. • Higher level of OH· was detected after combined disintegration than Fenton.

  1. Ultrasound coupled with Fenton oxidation pre-treatment of sludge to release organic carbon, nitrogen and phosphorus

    International Nuclear Information System (INIS)

    Gong, Changxiu; Jiang, Jianguo; Li, De'an

    2015-01-01

    We focused on the effects of ultrasound and Fenton reagent in ultrasonic coupling Fenton oxidation (U + F) pre-treatment processes on the disintegration of wastewater treatment plant sludge. The results demonstrated that U + F treatment could significantly increase soluble COD, TOC, total N, proteins, total P and PO 4 3− concentrations in sludge supernatant. This method was more effective than ultrasonic (U) or Fenton oxidation (F) treatment alone. U + F treatment increased the soluble COD by 2.1- and 1.4-fold compared with U and F alone, respectively. U + F treatment increased the total N and P by 1.7- and 2.2-fold, respectively, compared with F alone. After U + F treatment, sludge showed a considerably finer particle size and looser microstructure based on scanning electron microscopy, and the highest OH· signal intensity increased from 568.7 by F treatment to 1106.3 using electron spin resonance. This demonstrated that U + F treatment induces disintegration of sludge and release of organic carbon, nitrogen and phosphorus better. - Highlights: • Combined ultrasound–Fenton pre-treatment was proposed for sludge disintegration. • Ultrasound–Fenton significantly increased carbon, nitrogen and phosphorus release. • Higher level of OH· was detected after combined disintegration than Fenton

  2. Estimation of pump operational state with model-based methods

    International Nuclear Information System (INIS)

    Ahonen, Tero; Tamminen, Jussi; Ahola, Jero; Viholainen, Juha; Aranto, Niina; Kestilae, Juha

    2010-01-01

    Pumps are widely used in industry, and they account for 20% of the industrial electricity consumption. Since the speed variation is often the most energy-efficient method to control the head and flow rate of a centrifugal pump, frequency converters are used with induction motor-driven pumps. Although a frequency converter can estimate the operational state of an induction motor without external measurements, the state of a centrifugal pump or other load machine is not typically considered. The pump is, however, usually controlled on the basis of the required flow rate or output pressure. As the pump operational state can be estimated with a general model having adjustable parameters, external flow rate or pressure measurements are not necessary to determine the pump flow rate or output pressure. Hence, external measurements could be replaced with an adjustable model for the pump that uses estimates of the motor operational state. Besides control purposes, modelling the pump operation can provide useful information for energy auditing and optimization purposes. In this paper, two model-based methods for pump operation estimation are presented. Factors affecting the accuracy of the estimation methods are analyzed. The applicability of the methods is verified by laboratory measurements and tests in two pilot installations. Test results indicate that the estimation methods can be applied to the analysis and control of pump operation. The accuracy of the methods is sufficient for auditing purposes, and the methods can inform the user if the pump is driven inefficiently.

  3. Preliminary calculations of release rates from spent fuel in a tuff repository

    International Nuclear Information System (INIS)

    Apted, M.J.; O'Connell, W.J.; Lee, K.H.; MacIntyre, A.T.; Ueng, T.S.; Pigford, T.H.; Lee, W.W.L.

    1991-01-01

    Time-dependent release rates of Tc-99, I-129, Cs-135, and Np-237 have been calculated for wet-drip and moist-continuous release modes from the engineered barrier system of a potential nuclear waste repository in unsaturated tuff, representative of a possible repository at Yucca Mountain in southern Nevada. We describe the modes of water contact and of release of dissolved radionuclides to the surrounding intact rock, and the corresponding calculational models. We list the parameter values adopted, and then present numerical results, conclusions, and recommendations. 21 refs., 5 figs., 2 tabs

  4. Microfluidic Device for Controllable Chemical Release via Field-Actuated Membrane Incorporating Nanoparticles

    Directory of Open Access Journals (Sweden)

    Xiang Wang

    2013-01-01

    Full Text Available We report a robust magnetic-membrane-based microfluidic platform for controllable chemical release. The magnetic membrane was prepared by mixing polydimethylsiloxane (PDMS and carbonyl-iron nanoparticles together to obtain a flexible thin film. With combined, simultaneous regulation of magnetic stimulus and mechanical pumping, the desired chemical release rate can easily be realized. For example, the dose release experimental data was well fitted by a mathematical sigmoidal model, exhibiting a typical dose-response relationship, which shows promise in providing significant guidance for on-demand drug delivery. To test the platform’s feasibility, our microfluidic device was employed in an experiment involving Escherichia coli culture under controlled antibiotic ciprofloxacin exposure, and the expected outcomes were successfully obtained. Our experimental results indicate that such a microfluidic device, with high accuracy and easy manipulation properties, can legitimately be characterized as active chemical release system.

  5. Microfluidic Device for Controllable Chemical Release via Field-Actuated Membrane Incorporating Nanoparticles

    KAUST Repository

    Wang, Xiang; Li, Shunbo; Wang, Limu; Yi, Xin; Hui, Yu Sanna; Qin, Jianhua; Wen, Weijia

    2013-01-01

    We report a robust magnetic-membrane-based microfluidic platform for controllable chemical release. The magnetic membrane was prepared by mixing polydimethylsiloxane (PDMS) and carbonyl-iron nanoparticles together to obtain a flexible thin film. With combined, simultaneous regulation of magnetic stimulus and mechanical pumping, the desired chemical release rate can easily be realized. For example, the dose release experimental data was well fitted by a mathematical sigmoidal model, exhibiting a typical dose-response relationship, which shows promise in providing significant guidance for on-demand drug delivery. To test the platform’s feasibility, our microfluidic device was employed in an experiment involving Escherichia coli culture under controlled antibiotic ciprofloxacin exposure, and the expected outcomes were successfully obtained. Our experimental results indicate that such a microfluidic device, with high accuracy and easy manipulation properties, can legitimately be characterized as active chemical release system.

  6. Microfluidic Device for Controllable Chemical Release via Field-Actuated Membrane Incorporating Nanoparticles

    KAUST Repository

    Wang, Xiang

    2013-01-01

    We report a robust magnetic-membrane-based microfluidic platform for controllable chemical release. The magnetic membrane was prepared by mixing polydimethylsiloxane (PDMS) and carbonyl-iron nanoparticles together to obtain a flexible thin film. With combined, simultaneous regulation of magnetic stimulus and mechanical pumping, the desired chemical release rate can easily be realized. For example, the dose release experimental data was well fitted by a mathematical sigmoidal model, exhibiting a typical dose-response relationship, which shows promise in providing significant guidance for on-demand drug delivery. To test the platform’s feasibility, our microfluidic device was employed in an experiment involving Escherichia coli culture under controlled antibiotic ciprofloxacin exposure, and the expected outcomes were successfully obtained. Our experimental results indicate that such a microfluidic device, with high accuracy and easy manipulation properties, can legitimately be characterized as active chemical release system.

  7. Liquid-Phase Heat-Release Rates of the Systems Hydrazine-Nitric Acid and Unsymmetrical Dimethylhydrazine-Nitric Acid

    Science.gov (United States)

    Somogyi, Dezso; Feiler, Charles E.

    1960-01-01

    The initial rates of heat release produced by the reactions of hydrazine and unsymmetrical dimethylhydrazine with nitric acid were determined in a bomb calorimeter under conditions of forced mixing. Fuel-oxidant weight ratio and injection velocity were varied. The rate of heat release apparently depended on the interfacial area between the propellants. Above a narrow range of injection velocities representing a critical amount of interfacial area, the rates reached a maximum and were almost constant with injection velocity. The maximum rate for hydrazine was about 70 percent greater than that for unsymmetrical dimethylhydrazine. The total heat released did not vary with mixture ratio over the range studied.

  8. Supercritical waste oxidation pump investigation

    International Nuclear Information System (INIS)

    Thurston, G.; Garcia, K.

    1993-02-01

    This report investigates the pumping techniques and pumping equipment that would be appropriate for a 5,000 gallon per day supercritical water oxidation waste disposal facility. The pumps must boost water, waste, and additives from atmospheric pressure to approximately 27.6 MPa (4,000 psia). The required flow ranges from 10 gpm to less than 0.1 gpm. For the higher flows, many commercial piston pumps are available. These pumps have packing and check-valves that will require periodic maintenance; probably at 2 to 6 month intervals. Several commercial diaphragm pumps were also discovered that could pump the higher flow rates. Diaphragm pumps have the advantage of not requiring dynamic seals. For the lower flows associated with the waste and additive materials, commercial diaphragm pumps. are available. Difficult to pump materials that are sticky, radioactive, or contain solids, could be injected with an accumulator using an inert gas as the driving mechanism. The information presented in this report serves as a spring board for trade studies and the development of equipment specifications

  9. Impaired sarcoplasmic reticulum Ca(2+) release rate after fatiguing stimulation in rat skeletal muscle

    DEFF Research Database (Denmark)

    Ørtenblad, Niels; Sjøgaard, G; Madsen, Klavs

    2000-01-01

    during the first 0.5-1 h the metabolic state recovered to resting levels, and a slow phase from 1-3 h characterized by a rather slow recovery of the mechanical properties. The recovery of SR Ca(2+) release rate was closely correlated to +dF/dt during the slow phase of recovery (r(2) = 0.51; P ... to 66% that persisted for 1 h, followed by a gradual recovery to 87% of prefatigue release rate at 3 h recovery. Tetanic force and rate of force development (+dF/dt) and relaxation (-dF/dt) were depressed by approximately 80% after stimulation. Recovery occurred in two phases: an initial phase, in which......The purpose of the study was to characterize the sarcoplasmic reticulum (SR) function and contractile properties before and during recovery from fatigue in the rat extensor digitorum longus muscle. Fatiguing contractions (60 Hz, 150 ms/s for 4 min) induced a reduction of the SR Ca(2+) release rate...

  10. Knudsen pump driven by a thermoelectric material

    International Nuclear Information System (INIS)

    Pharas, Kunal; McNamara, Shamus

    2010-01-01

    The first use of a thermoelectric material in the bidirectional operation of a gas pump using thermal transpiration has been demonstrated. The thermoelectric material maintains a higher temperature difference which favors thermal transpiration and thus increases the efficiency of gas pumping. Since the hot and cold sides of the thermoelectric material are reversible, the direction of the pump may be changed by reversing the electrical current direction. Two different pump designs are presented that illustrate some of the design tradeoffs. The pumps are characterized by measuring the pressure difference that may be generated and by measuring the flow rate in the forward and reverse directions. For a pump composed of a porous material with a pore size of 100 nm, a maximum flow rate of 0.74 cm 3 min −1 and a maximum pressure of 1.69 kPa are achieved

  11. SUSPENSION-FEEDING IN MARINE SPONGES HALICHONDRIA-PANICEA AND HALICLONA-URCEOLUS - EFFECTS OF TEMPERATURE ON FILTRATION-RATE AND ENERGY-COST OF PUMPING

    DEFF Research Database (Denmark)

    Riisgård, H.U.; Thomassen, S.; Jakobsen, H.

    1993-01-01

    Filtration rate (measured as clearance of algal cells) was measured at different temperatures in the sponge Halichondria panicea. An increase in water temperature from 6 to 12-degrees-C caused the mean filtration rate to increase 4.3 +/- 2.3 times. This value was higher than previously found...... for other marine ciliary suspension-feeding animals. Filtration rate at 12-degrees-C was also measured in Haliclona urceolus by means of an indirect clearance method in addition to a direct technique for measuring pumping rate. It was found that the 2 sponge species had near-identical filtration rates......, with maximum rates of approximately 60 ml min-1 (g dry weight)-1 at 12-degrees-C. The normal pump pressure, or operating point O(p), of a standard sponge (based on our own measurements and calculations from literature data for a 0.1 g dry weight Haliclona sp.) was estimated as the sum of main contributions...

  12. Sodium pumping: pump problems

    International Nuclear Information System (INIS)

    Guer, M.; Guiton, P.

    Information on sodium pumps for LMFBR type reactors is presented concerning ring pump design, pool reactor pump design, secondary pumps, sodium bearings, swivel joints of the oscillating annulus, and thermal shock loads

  13. Special considerations for electric submersible pump applications in underpressured reservoirs

    International Nuclear Information System (INIS)

    Powers, M.L.

    1991-01-01

    This paper investigates the effect of electric submersible pump performance tolerances and minor speed variations on the producing rate of wells completed in underpressured reservoirs, and presents ESP design considerations which are unique for this class of wells. These wells require considerable head to initiate flow and have relatively flat well-load curves. Pumps that operate near their maximum recommended rate have steep performance curves. it is shown that this minimizes the effect of an underperforming pump on producing rate. Equations are developed for calculating the effects of pump performance and speed. Application requires evaluating the slopes of the pump performance curve and well-load curve at design rate. Utility of these equations is demonstrated by practical examples. It is also demonstrated that flow-stall can easily occur in underpressured reservoir applications when pumps designed to operate near their minimum recommended rate are installed

  14. Laboratory evaluation of the emulsifying characteristics of pumps

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, A.C.; Guzdar, A.R.; Friswell, D.R.

    1973-10-01

    The program was devoted to a laboratory investigation of the emulsifying characteristics of different pumps suitable for shipboard pumping of bilge and ballast water oily wastes. The tests were designed to investigate the effect of several parameters, such as oil type, input oil concentration, detergent, pump operating characteristics (pressure and flow rate), and salt vs. fresh water, on emulsification. Tests were conducted on the Foster-Miller test loop. No. 2 fuel oil, lubricating oil and No. 6 fuel oil were the oils tested at concentrations ranging from 1 to 10%. The oils were tested with and without the addition of 10% Gamlen D surfactant. The pumps used were a Parker Diaphragm pump, a Blackmer Sliding Vane pump, an Ingersoll Rand Centrifugal pump, and a Deming Centrifugal pump. Pump pressure ranged from 10 to 60 psi and flow rates from 10 to 100 gpm. A total of 270 tests was conducted covering 198 different operating points, 108 concerning pump comparison, 54 concerning oil concentration and surfactant, and 45 concerning salt water.

  15. The effect of culture density and proliferation rate on the expression of ouabain-sensitive Na/K ATPase pumps in cultured human retinal pigment epithelium

    International Nuclear Information System (INIS)

    Burke, J.M.; Jaffe, G.J.; Brzeski, C.M.

    1991-01-01

    The number and activity of ouabain-sensitive Na/K ATPase pumps expressed by many cell types in vitro, including human retinal pigment epithelial cells (RPE), have been shown to decline with increasing culture density. Cell proliferation also declined as cultures became dense so it was unclear if pump number was modulated by cell proliferation or culture confluency. By exposing RPE cultures to various feeding regimens, using culture medium containing or lacking serum, it was possible to produce RPE cultures with a range of culture densities and growth rates. These were analyzed for proliferative activity by quantifying [ 3 H]thymidine incorporation and for Na/K ATPase pump number by measuring specific [ 3 H]ouabain binding. The results suggest that pump number is modulated by culture density and, further, that the density-dependent regulation of pump number requires serum. Although density-dependent modulation of culture growth is also serum requiring, cell proliferation and pump number did not appear to be related; cultures of similar density which differed significantly in growth rate had similar numbers of pumps. The view that elevated numbers of pumps were not necessarily found in proliferating cells was further supported by qualitative examination of radioautographs of cells dually labeled with [ 3 H]thymidine and [ 3 H]ouabain. Cycling cells which had [ 3 H]thymidine-labeled nuclei did not have notably higher labeling with [ 3 H]ouabain. However, [ 3 H]ouabain labeling, as an indicator of pump site number and distribution, did vary among cells in an RPE population and also within individual cells. This latter observation suggests that unpolarized RPE cells in sparse cultures may have regionally different requirements for ionic regulation

  16. Review of magnetohydrodynamic pump applications

    Directory of Open Access Journals (Sweden)

    O.M. Al-Habahbeh

    2016-06-01

    Full Text Available Magneto-hydrodynamic (MHD principle is an important interdisciplinary field. One of the most important applications of this effect is pumping of materials that are hard to pump using conventional pumps. In this work, the progress achieved in this field is surveyed and organized according to the type of application. The literature of the past 27 years is searched for the major developments of MHD applications. MHD seawater thrusters are promising for a variety of applications requiring high flow rates and velocity. MHD molten metal pump is important replacement to conventional pumps because their moving parts cannot stand the molten metal temperature. MHD molten salt pump is used for nuclear reactor coolants due to its no-moving-parts feature. Nanofluid MHD pumping is a promising technology especially for bioapplications. Advantages of MHD include silence due to no-moving-parts propulsion. Much progress has been made, but with MHD pump still not suitable for wider applications, this remains a fertile area for future research.

  17. Size Effect on Failure of Pre-stretched Free-Standing Nanomembranes

    Directory of Open Access Journals (Sweden)

    Cheng Wenlong

    2010-01-01

    Full Text Available Abstract Free-standing nanomembranes are two-dimensional materials with nanometer thickness but can have macroscopic lateral dimensions. We develop a fracture model to evaluate a pre-stretched free standing circular ultrathin nanomembrane and establish a relation between the energy release rate of a circumferential interface crack and the pre-strain in the membrane. Our results demonstrate that detachment cannot occur when the radius of the membrane is smaller than a critical size. This critical radius is inversely proportional to the Young’s modulus and square of the pre-strain of the membrane.

  18. Energy efficiency in pumps

    International Nuclear Information System (INIS)

    Kaya, Durmus; Yagmur, E. Alptekin; Yigit, K. Suleyman; Kilic, Fatma Canka; Eren, A. Salih; Celik, Cenk

    2008-01-01

    In this paper, 'energy efficiency' studies, done in a big industrial facility's pumps, are reported. For this purpose; the flow rate, pressure and temperature have been measured for each pump in different operating conditions and at maximum load. In addition, the electrical power drawn by the electric motor has been measured. The efficiencies of the existing pumps and electric motor have been calculated by using the measured data. Potential energy saving opportunities have been studied by taking into account the results of the calculations for each pump and electric motor. As a conclusion, improvements should be made each system. The required investment costs for these improvements have been determined, and simple payback periods have been calculated. The main energy saving opportunities result from: replacements of the existing low efficiency pumps, maintenance of the pumps whose efficiencies start to decline at certain range, replacements of high power electric motors with electric motors that have suitable power, usage of high efficiency electric motors and elimination of cavitation problems

  19. PRE-ELECTIONAL DECREASE OF THE UNEMPLOYMENT RATE

    Directory of Open Access Journals (Sweden)

    Damjan Miličević

    2013-02-01

    Full Text Available Opportunistic business cycle models test whether the current government has the ability to reduce unemployment in pre-election period. First opportunistic business cycle models tested regressions using unemployment rate as the dependent variable, and for explanatory variables used unemployment rate in the previous two periods and political dummy variable defined as unity several quarters prior to election and zero elsewhere. Such models did not find evidence of opportunistic cycle for unemployment. Haynes and Stone in their model estimated regressions using unemployment as the dependent variable and sixteen dummy variables as explanatory variables (one for each quarter in the Presidential electoral term. Results showed that unemployment has roughly sinusoidal sixteen quarter cycle, where unemployment troughs on average the quarter of the election. Mentioned models are tested with data for the United States for the period from 1948 to 2011 where regressions results coincide with models mentioned in the article.

  20. Measurement and evaluation of pumping speed and gas discharge characteristics of titanium getter pump by conductance modulation method

    International Nuclear Information System (INIS)

    Terada, Keiko; Okano, Tatsuo; Tsuji, Hiroshi.

    1989-01-01

    The conductance modulation method is designed to determine the pumping speed from a known conductance. With the method, the intrinsic pumping speed Sp and net pumping speed S * can be determined in a wide range up to near the ultimate pressure. In the present study, the pumping speed and gas discharge rate of a titanium getter pump at 77K are analyzed, and the results are compared with measurements made at room temperature. The pressure in a vacuum chamber depends on the gas load and the pumping speed. The pressure varies from P A to P B as the conductance of the orifice is changed from C A to C B . The ultimate pressure also changes from P AO to P BO . The intrinsic and net pumping speeds can be calculated from P A , P B , P AO and P BO . The major feature of the conductance modulation method is that the intrinsic and net pumping speeds can be determined from a change in the conductance without knowing the sensitivity of the vacuum meter or the flow rate of gas entering the chamber from outside. With this feature, the method is very effective for measuring the balance between the gas discharge and pumping speed near the ultimate pressure. (N.K.)

  1. Pump efficiency in solar-energy systems

    Science.gov (United States)

    1978-01-01

    Study investigates characteristics of typical off-the-shelf pumping systems that might be used in solar systems. Report includes discussion of difficulties in predicting pump efficiency from manufacturers' data. Sample calculations are given. Peak efficiencies, flow-rate control, and noise levels are investigated. Review or theory of pumps types and operating characteristics is presented.

  2. Effect of non-condensable gas on heat transfer in steam turbine condenser and modelling of ejector pump system by controlling the gas extraction rate through extraction tubes

    International Nuclear Information System (INIS)

    Strušnik, Dušan; Golob, Marjan; Avsec, Jurij

    2016-01-01

    Graphical abstract: Control of the amount of the pumped gases through extraction tubes. The connecting locations interconnect the extraction tubes for STC gas pumping. The extraction tubes are fitted with 3 control valves to control the amount of the pumped gas depending on the temperature of the pumped gas. The amount of the pumped gas increases through the extraction tubes, where the pumped gases are cooler and decreases, at the same time, through the extraction tubes, where the pumped gases are warmer. As a result, pumping of a larger amount of NCG is ensured and of a smaller amount of CG, given that the NCG concentration is the highest on the colder places. This way, the total amount of the pumped gases from the STC can be reduced, the SEPS operates more efficiently and consumes less energy for its operation. - Highlights: • Impact of non-condensable gas on heat transfer in a steam turbine condenser. • The ejector system is optimised by selecting a Laval nozzle diameter. • Simulation model of the control of the amount of pumped gases through extraction tubes. • Neural network and fuzzy logic systems used to control gas extraction rate. • Simulation model was designed by using real process data from the thermal power plant. - Abstract: The paper describes the impact of non-condensable gas (NCG) on heat transfer in a steam turbine condenser (STC) and modelling of the steam ejector pump system (SEPS) by controlling the gas extraction rate through extraction tubes. The ideal connection points for the NCG extraction from the STC are identified by analysing the impact of the NCG on the heat transfer and measuring the existing system at a thermal power plant in Slovenia. A simulation model is designed using the Matlab software and Simulink, Neural Net Work, Fuzzy Logic and Curve Fitting Toolboxes, to control gas extraction rate through extraction tubes of the gas pumped from the STC, thus optimising the operation of the steam ejector pump system (SEPS). The

  3. Dynamic energy release rate in couple-stress elasticity

    International Nuclear Information System (INIS)

    Morini, L; Piccolroaz, A; Mishuris, G

    2013-01-01

    This paper is concerned with energy release rate for dynamic steady state crack problems in elastic materials with microstructures. A Mode III semi-infinite crack subject to loading applied on the crack surfaces is considered. The micropolar behaviour of the material is described by the theory of couple-stress elasticity developed by Koiter. A general expression for the dynamic J-integral including both traslational and micro-rotational inertial contributions is derived, and the conservation of this integral on a path surrounding the crack tip is demonstrated

  4. Unsteady numerical simulation for gas–liquid two-phase flow in self-priming process of centrifugal pump

    International Nuclear Information System (INIS)

    Huang, Si; Su, Xianghui; Guo, Jing; Yue, Le

    2014-01-01

    Highlights: • The transient gas–liquid two-phase flow fields in the self-priming centrifugal pump are simulated. • The self-priming time and performance are estimated. • The air void fraction and two phase distribution are obtained.· The hole on the volute plays a significant role for gas exhausting. • The frequency of the impulsive pressure basically conforms to that of the air exhausted out of the pump. - Abstract: Self-priming pumps start up without pre-irrigation, and then work as common pumps when air in the pump is exhausted. The transient gas–liquid flow at the start-up stage inside a self-priming pump is an interesting process which greatly influences performance of the pump. In this paper, a conventional vertical self-priming centrifugal pump was selected as the object. Using unsteady numerical simulation, the authors investigated the transient gas–liquid two-phase flow in the self-priming centrifugal pump during the self-priming process. The main innovation in the simulation was that a section of the suction pipe filled with air was set as the initial condition, which conformed to the actual self-priming conditions. The gas–liquid two-phase distribution, the pressure and velocity in relation to time were computed and analyzed. Flow rates of both phases with time at the pump inlet and outlet were obtained based on the simulation, which could be used to estimate the self-priming time and other performance parameters. Finally, the numerical method and results for gas–liquid two-phase flow in the self-priming pump was partly validated by the pump performance test

  5. Radioactive air emissions notice of construction use of a portable exhauster on single-shell tanks during salt well pumping; FINAL

    International Nuclear Information System (INIS)

    HOMAN, N.A.

    1999-01-01

    This document serves as a notice of construction (NOC), pursuant to the requirements of Washington Administrative Code (WAC) 246-247-060, and as a request for approval to construct, pursuant to 40 Code of Federal Regulations (CFR) 61.07, portable exhausters for use on singleshell tanks (SSTs) during salt well pumping. Table 1-1 lists SSTs covered by this NOC. This GOC also addresses other activities that are performed in support of salt well pumping but do not require the application of a portable exhauster. Specifically this NOC analyzes the following three activities that have the potential for emissions. (1) Salt well pumping (i.e., the actual transferring of waste from one tank to another) under nominal tank operating conditions. Nominal tank operating conditions include existing passive breathing rates. (2) Salt well pumping (the actual transferring of waste from one tank to another) with use of a portable exhauster. (3) Use of a water lance on the waste to facilitate salt well screen and salt well jet pump installation into the waste. This activity is to be performed under nominal (existing passive breathing rates) tank operating conditions. The use of portable exhausters represents a cost savings because one portable exhauster can be moved back and forth between SSTs as schedules for salt well pumping dictate. A portable exhauster also could be used to simultaneously exhaust more than one SST during salt well pumping. The primary objective of providing active ventilation to these SSTs during salt well pumping is to reduce the risk of postulated accidents to remain within risk guidelines. It is anticipated that salt well pumping will release gases entrapped within the waste as the liquid level is lowered, because of less hydrostatic force keeping the gases in place. Hanford Site waste tanks must comply with the Tank Farms authorization basis (DESH 1997) that requires that the flammable gas concentration be less than 25 percent of the lower flammability limit

  6. Evaluation of rate of swelling and erosion of verapamil (VRP) sustained-release matrix tablets.

    Science.gov (United States)

    Khamanga, Sandile M; Walker, Roderick B

    2006-01-01

    Tablets manufactured in-house were compared to a marketed sustained-release product of verapamil to investigate the rate of hydration, erosion, and drug-release mechanism by measuring the wet and subsequent dry weights of the products. Swelling and erosion rates depended on the polymer and granulating fluid used, which ultimately pointed to their permeability characteristics. Erosion rate of the marketed product was highest, which suggests that the gel layer that formed around these tablets was weak as opposed to the robust and resistant layers of test products. Anomalous and near zero-order transport mechanisms were dominant in tests and commercial product, respectively.

  7. Pumps and pump facilities. 2. ed.

    International Nuclear Information System (INIS)

    Bohl, W.; Bauerfeind, H.; Gutmann, G.; Leuschner, G.; Matthias, H.B.; Mengele, R.; Neumaier, R.; Vetter, G.; Wagner, W.

    1981-01-01

    This book deals with the common fundamental aspects of liquid pumps and gives an exemplary choice of the most important kinds of pumps. The scientific matter is dealt with by means of practical mathematical examples among other ways of presenting the matter. Survey of contents: Division on main operational data of pumps - pipe characteristics - pump characteristics - suction behaviour of the pumps - projecting and operation of rotary pumps - boiler feed pumps - reactor feed pumps - oscillating positive-displacement pumps - eccentric spiral pumps. (orig./GL) [de

  8. Absorption heat pump for space applications

    Science.gov (United States)

    Nguyen, Tuan; Simon, William E.; Warrier, Gopinath R.; Woramontri, Woranun

    1993-01-01

    In the first part, the performance of the Absorption Heat Pump (AHP) with water-sulfuric acid and water-magnesium chloride as two new refrigerant-absorbent fluid pairs was investigated. A model was proposed for the analysis of the new working pairs in a heat pump system, subject to different temperature lifts. Computer codes were developed to calculate the Coefficient of Performance (COP) of the system with the thermodynamic properties of the working fluids obtained from the literature. The study shows the potential of water-sulfuric acid as a satisfactory replacement for water-lithium bromide in the targeted temperature range. The performance of the AHP using water-magnesium chloride as refrigerant-absorbent pair does not compare well with those obtained using water-lithium bromide. The second part concentrated on the design and testing of a simple ElectroHydrodynamic (EHD) Pump. A theoretical design model based on continuum electromechanics was analyzed to predict the performance characteristics of the EHD pump to circulate the fluid in the absorption heat pump. A numerical method of solving the governing equations was established to predict the velocity profile, pressure - flow rate relationship and efficiency of the pump. The predicted operational characteristics of the EHD pump is comparable to that of turbomachinery hardware; however, the overall efficiency of the electromagnetic pump is much lower. An experimental investigation to verify the numerical results was conducted. The pressure - flow rate performance characteristics and overall efficiency of the pump obtained experimentally agree well with the theoretical model.

  9. Release of radon contaminants from Yucca Mountain: The role of buoyancy driven flow

    International Nuclear Information System (INIS)

    Sullivan, T.M.; Pescatore, C.

    1994-02-01

    The potential for the repository heat source to promote buoyancy driven flow and thereby cause release of radon gas out of Yucca Mountain has been examined through a critical review of the theoretical and experimental studies of this process. The review indicates that steady-state buoyancy enhanced release of natural radon and other contaminant gases should not be a major concern at Yucca Mountain. Barometric pumping and wind pumping are identified as two processes that will have a potentially greater effect on surface releases of gases

  10. The effect of culture density and proliferation rate on the expression of ouabain-sensitive Na/K ATPase pumps in cultured human retinal pigment epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J.M.; Jaffe, G.J.; Brzeski, C.M. (Medical College of Wisconsin, Milwaukee (USA))

    1991-06-01

    The number and activity of ouabain-sensitive Na/K ATPase pumps expressed by many cell types in vitro, including human retinal pigment epithelial cells (RPE), have been shown to decline with increasing culture density. Cell proliferation also declined as cultures became dense so it was unclear if pump number was modulated by cell proliferation or culture confluency. By exposing RPE cultures to various feeding regimens, using culture medium containing or lacking serum, it was possible to produce RPE cultures with a range of culture densities and growth rates. These were analyzed for proliferative activity by quantifying ({sup 3}H)thymidine incorporation and for Na/K ATPase pump number by measuring specific ({sup 3}H)ouabain binding. The results suggest that pump number is modulated by culture density and, further, that the density-dependent regulation of pump number requires serum. Although density-dependent modulation of culture growth is also serum requiring, cell proliferation and pump number did not appear to be related; cultures of similar density which differed significantly in growth rate had similar numbers of pumps. The view that elevated numbers of pumps were not necessarily found in proliferating cells was further supported by qualitative examination of radioautographs of cells dually labeled with ({sup 3}H)thymidine and ({sup 3}H)ouabain. Cycling cells which had ({sup 3}H)thymidine-labeled nuclei did not have notably higher labeling with ({sup 3}H)ouabain. However, ({sup 3}H)ouabain labeling, as an indicator of pump site number and distribution, did vary among cells in an RPE population and also within individual cells. This latter observation suggests that unpolarized RPE cells in sparse cultures may have regionally different requirements for ionic regulation.

  11. Pump cavitation and inducer design

    International Nuclear Information System (INIS)

    Heslenfeld, M.W.; Hes, M. de

    2002-01-01

    Details of past work on sodium pump development and cavitation studies executed mainly for SNR 300 were reported earlier. Among the requirements for large sodium pumps are long life (200000 hours up to 300000 hours) and small size of impeller and pump, fully meeting the process and design criteria. These criteria are the required 'Q, H, r characteristics' in combination with a low NPSH value and the avoidance of cavitation damage to the pump. The pump designer has to develop a sound hydraulic combination consisting of suction arrangement, impeller design and diffuser. On the other hand the designer is free to choose an optimal pump speed. The pump speed in its turn influences the rotor dynamic pump design and the pump drive. The introduction of the inducer as an integral part of the pump design is based on following advantages: no tip cavitation; (possible) cavitation bubbles move to the open centre due to centrifugal forces on the fluid; the head of the inducer improves the inlet conditions of the impeller. The aim of an inducer is the increase in the suction specific speed (SA value) of a pump whereby the inducer functions as a pressure source improving the impeller inlet conditions. With inducer-impeller combinations values up to SA=15000 are realistic. With the use of an inducer the overall pump sizes can be reduced with Ca. 30%. Pumps commonly available have SA values up to a maximum of ca. 10000. A development programme was executed for SNR 300 in order to reach an increase of the suction specific speed of the impeller from SA 8200 to SA 11000. Further studies to optimize pumps design for the follow up line introduced the 'inducer acting as a pre-impeller' development. This programme was executed in the period 1979-1981. At the FDO premises a scale 1 2.8 inducer impeller combination with a suction specific speed SA=15000 was developed, constructed and tested at the water test rig. This water test rig is equipped with a perspex pipe allowing also visualisation

  12. Mixer pump long term operations plan for Tank 241-SY-101 mitigation

    International Nuclear Information System (INIS)

    Irwin, J.J.

    1994-01-01

    This document provides the general Operations Plan for performance of the mixer pump long term operations for Tank 241-SY-101 mitigation of gas retention and periodic release in Tank 101-SY. This operations plan will utilize a 112 kW (150 hp) mixing pump to agitate/suspend the particulates in the tank

  13. Glucose pump test can be used to measure blood flow rate of native arteriovenous fistula in chronic hemodialysis.

    Science.gov (United States)

    Yavuz, Y C; Selcuk, N Y; Altıntepe, L; Güney, I; Yavuz, S

    2018-01-01

    In chronic hemodialysis patients, the low flow of vascular access may leads to inadequate dialysis, increased rate of hospitalization, morbidity, and mortality. It was found that surveillance should be performed for native arteriovenous (AV) should not be performed for AV graft in various studies. However, surveillance was done in graft AV fistulas in most studies. Doppler ultrasonography (US) was suggested for surveillance of AV fistulas by the last vascular access guideline of National Kidney Foundation Disease Outcomes Quality Initiative (NKF KDOQI). The aim of study is to determine whether glucose pump test (GPT) is used for surveillance of native AV fistulas by using Doppler US as reference. In 93 chronic hemodialysis patients with native AV fistula, blood flow rates were measured by Doppler US and GPT. For GPT, glucose was infused to 16 mL/min by pump and was measured at basal before the infusion and 11 s after the start of the infusion by glucometer. Doppler US was done by an expert radiologist. Used statistical tests were Mann-Whitney U test, Friedman test, regression analysis, and multiple regression analysis. Median values of blood flow rates measured by GPT (707 mL/min) and by Doppler US (700 mL/min) were not different (Z = 0.414, P = 0.678). Results of GPT and Doppler US measurements were positive correlate by regression analysis. The mean GPT value of diabetic patients (n = 39; 908 mL/min) was similar to that of nondiabetic patients (n = 54; 751 mL/min; Z = 1.31, P = 0.188). GPT values measured at three different dialysis session did not differ from each other that by Friedman test (F = 0.92, P = 0.39). This showed that GPT was stable and reliable. Glucose pump test can be used to measure blood flow rate of native AV fistula. GPT is an accurate and reliable test.

  14. Radioisotopic composition of yellowcake: an estimation of stack release rates

    International Nuclear Information System (INIS)

    Momeni, M.H.; Kisieleski, W.E.; Rayno, D.R.; Sabau, C.S.

    1979-12-01

    Uranium concentrate (yellowcake) composites from four mills (Anaconda, Kerr-McGee, Highland, and Uravan) were analyzed for U-238, U-235, U-234, Th-230, Ra-226, and Pb-210. The ratio of specific activities of U-238 to U-234 in the composites suggested that secular radioactive equilibrium exists in the ore. The average activity ratios in the yellowcake were determined to be 2.7 x 10 -3 (Th-230/U-238), 5 x 10 -4 (Ra-226/U-238) and 2 x 10 -4 (Pb-210/U-238). Based on earlier EPA measurements of the release rates from the stacks, the amount of yellowcake released was determined to be 0.1% of the amount processed

  15. Detection of pump degradation

    International Nuclear Information System (INIS)

    Casada, D.

    1995-01-01

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous special vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Pump head and flow rate are also monitored, per code requirements. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition; advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed

  16. Wireless implantable chip with integrated nitinol-based pump for radio-controlled local drug delivery.

    Science.gov (United States)

    Fong, Jeffrey; Xiao, Zhiming; Takahata, Kenichi

    2015-02-21

    We demonstrate an active, implantable drug delivery device embedded with a microfluidic pump that is driven by a radio-controlled actuator for temporal drug delivery. The polyimide-packaged 10 × 10 × 2 mm(3) chip contains a micromachined pump chamber and check valves of Parylene C to force the release of the drug from a 76 μL reservoir by wirelessly activating the actuator using external radio-frequency (RF) electromagnetic fields. The rectangular-shaped spiral-coil actuator based on nitinol, a biocompatible shape-memory alloy, is developed to perform cantilever-like actuation for pumping operation. The nitinol-coil actuator itself forms a passive 185 MHz resonant circuit that serves as a self-heat source activated via RF power transfer to enable frequency-selective actuation and pumping. Experimental wireless operation of fabricated prototypes shows successful release of test agents from the devices placed in liquid and excited by radiating tuned RF fields with an output power of 1.1 W. These tests reveal a single release volume of 219 nL, suggesting a device's capacity of ~350 individual ejections of drug from its reservoir. The thermal behavior of the activated device is also reported in detail. This proof-of-concept prototype validates the effectiveness of wireless RF pumping for fully controlled, long-lasting drug delivery, a key step towards enabling patient-tailored, targeted local drug delivery through highly miniaturized implants.

  17. Estimation of Leak Rate from the Emergency Pump Well in L-Area Complex Basin

    International Nuclear Information System (INIS)

    Duncan, A

    2005-01-01

    This report provides an estimate of the leak rate from the emergency pump well in L-basin that is to be expected during an off-normal event. This estimate is based on expected shrinkage of the engineered grout (i.e., controlled low strength material) used to fill the emergency pump well and the header pipes that provide the dominant leak path from the basin to the lower levels of the L-Area Complex. The estimate will be used to provide input into the operating safety basis to ensure that the water level in the basin will remain above a certain minimum level. The minimum basin water level is specified to ensure adequate shielding for personnel and maintain the ''as low as reasonably achievable'' concept of radiological exposure. The need for the leak rate estimation is the existence of a gap between the fill material and the header pipes, which penetrate the basin wall and would be the primary leak path in the event of a breach in those pipes. The gap between the pipe and fill material was estimated based on a full scale demonstration pour that was performed and examined. Leak tests were performed on full scale pipes as a part of this examination. Leak rates were measured to be on the order of 0.01 gallons/minute for completely filled pipe (vertically positioned) and 0.25 gallons/minute for partially filled pipe (horizontally positioned). This measurement was for water at 16 feet head pressure and with minimal corrosion or biofilm present. The effect of the grout fill on the inside surface biofilm of the pipes is the subject of a previous memorandum

  18. A new method for calculating energy release rate in tunnel excavation subjected to high in situ stress

    Directory of Open Access Journals (Sweden)

    Xiao Qinghua

    2016-03-01

    Full Text Available Based on energy theory, energy release rate (EER and local energy release rate (LEER, a new index called FERR (Fractional Energy Release Rate is proposed, and this method can not only evaluate the risk of rock burst, but also can point out the location of high risk and the scale of rockburst. The FERR index is applied to the TBM assembling tunnel in Jinping Hydro Power Station II to evaluate the scale and intensity of rockburst, as well as the location where rockburst occurs. With FDM method adopted, the energy release rate of 3 excavation plans are calculated and the scale and risk of rockburst is evaluated, and the location of high risk of rockburst is also mapped. With FERR used in the evaluation, the rockburst is nicely controlled which ensured the safety and construction schedule of the project.

  19. Influence of Strain Rate on Heat Release under Quasi-Static Stretching of Metals. Experiment

    Science.gov (United States)

    Zimin, B. A.; Sventitskaya, V. E.; Smirnov, I. V.; Sud'enkov, Yu. V.

    2018-04-01

    The paper presents the results of experimental studies of energy dissipation during a quasi-static stretching of metals and alloys at room temperature. The strain rates varied in the range of 10-3-10-2 s-1. Samples of M1 copper, AZ31B magnesium alloy, BT6 titanium, 12Cr18Ni10Ti steel, and D16AM aluminum alloy were analyzed. The experimental results demonstrated a significant dependence of the heat release on the strain rate in the absence of its influence on stress-strain diagrams for all the metals studied in this range of strain rates. The correlation of the changes in the character of heat release with the processes of structural transformations at various stages of plastic flow is shown on the qualitative level. A difference in the nature of the processes of heat release in materials with different ratios of the plasticity and strength is noted.

  20. Energy efficiency in pumps

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Durmus; Yagmur, E. Alptekin [TUBITAK-MRC, P.O. Box 21, 41470 Gebze, Kocaeli (Turkey); Yigit, K. Suleyman; Eren, A. Salih; Celik, Cenk [Engineering Faculty, Kocaeli University, Kocaeli (Turkey); Kilic, Fatma Canka [Department of Air Conditioning and Refrigeration, Kocaeli University, Kullar, Kocaeli (Turkey)

    2008-06-15

    In this paper, ''energy efficiency'' studies, done in a big industrial facility's pumps, are reported. For this purpose; the flow rate, pressure and temperature have been measured for each pump in different operating conditions and at maximum load. In addition, the electrical power drawn by the electric motor has been measured. The efficiencies of the existing pumps and electric motor have been calculated by using the measured data. Potential energy saving opportunities have been studied by taking into account the results of the calculations for each pump and electric motor. As a conclusion, improvements should be made each system. The required investment costs for these improvements have been determined, and simple payback periods have been calculated. The main energy saving opportunities result from: replacements of the existing low efficiency pumps, maintenance of the pumps whose efficiencies start to decline at certain range, replacements of high power electric motors with electric motors that have suitable power, usage of high efficiency electric motors and elimination of cavitation problems. (author)

  1. Vacuum pumping system for the JT-60 radio-frequency heating system

    International Nuclear Information System (INIS)

    Yokokura, Kenji; Ikeda, Yoshitaka; Imai, Tuyoshi; Suganuma, Kazuaki; Nagashima, Takashi

    1988-01-01

    The basic design requirements set up for the JT-60 radio-frequency heating system included: (1) rapid pumping of gas released upon application of a radio-frequency power to maintain the pressure in the launchers at 10 -2 - 10 -3 Pa or less, (2) incorporation of a gas analysis system that can operate under a strong field and high pressure (>10 -2 Pa) to permit remote controlled data collection and processing, and (3) low cost, multiple functions and high reliability. The vacuum pumping system, consisting of three units for low hybrid radio-frequency (LHRF) and one unit for ion cyclotron radio-frequency (ICRF), is connected to each launcher provided at the four ports of JT-60. The LHRF unit is composed of a main pump, an alumina joint for electrical insulation from the launcher, a metallic gate valve for isolation from the JT-60 vacuum region, and various vacuum gauges. Only a turbo-molecular pump is used for the ICRF system because a large-scale differential pumping is not required. A gas measuring system is incorporated which consists of a mass filter, personal computer, turbo-molecular pump, and variable flow valve equipped with an APG control. This system is designed to identify and make use of gas impurities released during the launcher aging process. The control system employed consists of a personal computer, interlock control board, data logger and other devices such as vacuum gages. (Nogami, K.)

  2. Effect of crack-microcracks interaction on energy release rates

    Science.gov (United States)

    Chudnovsky, A.; Wu, Shaofu

    1990-01-01

    The energy release rates associated with the main crack advancing into its surrounding damage zone, and the damage zone translation relative to the main crack, as well as the energy of interaction between the crack and the damage zone are analyzed. The displacement and stress fields for this crack-damage interaction problem are reconstructed by employing a semi-empirical stress analysis which involves experimental evaluation of the average microcrack density in the damage zone.

  3. Effects of Sediment Chemical Properties on Phosphorus Release Rates in the Sediment-Water Interface of the Steppe Wetlands.

    Science.gov (United States)

    He, Jing; Su, Derong; Lv, Shihai; Diao, Zhaoyan; Xie, Jingjie; Luo, Yan

    2017-11-22

    Rising temperature causes a process of phosphorus release, which can be characterized well using phosphorus release rates (V P ). The objective of the present study was to investigate the major factors affecting sediment phosphorus release rates through a wetland habitat simulation experiment. The results showed that the V P of different wetland sediments were different and changed with the order of W-R (river wetland) > W-L (lake wetland) > W-M (grassy marsh wetland) > W-A (reservoir wetland). The main driving factors which influenced sediment phosphorus flux velocity in the sediment-water interface were sediment B-SO₄ 2- , B-MBN and A-MBP content. Path analysis and determination coefficient analysis indicated the standard multiple regression equation for sediment phosphorus release rates in the sediment-water interface, and each main factor was Y = -0.105 + 0.096X₁ + 0.275X₂ - 0.010X₃ ( r = 0.416, p phosphorus release rates; X₁ is sediment B-SO₄ 2- content; X₂ is sediment B-MBN; and X₃ is sediment A-MBP content. Sediment B-SO₄ 2- , B-MBN and A-MBP content and the interaction between them were the main factors affecting sediment phosphorus release rates in the sediment-water interface. Therefore, these results suggest that soil chemical properties and microbial activities likely play an important role in phosphorus release rates in the sediment-water interface. We hope to provide effective scientific management and control methods for relevant environmental protection departments.

  4. Electron transfer rates and energy releases during denitrification of municipal wastewater

    DEFF Research Database (Denmark)

    Abdul-Talib, S.; Ujang, Z; Vollertsen, J.

    2004-01-01

    could be simplified by a two-stage process. In the first stage, nitrate was utilised with significant accumulation of nitrite. In the second stage nitrite was utilised when nitrate depleted. Denitrification rates during the two stages were expressed in terms of electron equivalents (e-eq.) in order...... to compare the process when differennt electron acceptors namlely, nitrate and nitrite were utilised. The energy release rates during the two stages were calculated and compared....

  5. Sensitivity of the engineered barrier system (EBS) release rate to alternative conceptual models of advective release from waste packages under dripping fractures

    International Nuclear Information System (INIS)

    Lee, J.H.; Atkins, J.E.; McNeish, J.A.; Vallikat, V.

    1996-01-01

    The first model assumed that dripping water directly contacts the waste form inside the ''failed'' waste package and radionuclides are released from the EBS by advection. The second model assumed that dripping water is diverted around the package (because of corrosion products plugging the perforations), thereby being prevented from directly contacting the waste form. In the second model, radionuclides were assumed to diffuse through the perforations, and, once outside the waste package, to be released from the EBS by advection. For the case with the second EBS release model, most radionuclides had lower peak EBS release rates than with the first model. Impacts of the alternative EBS release models were greater for the radionuclides with low solubility. The analysis indicated that the EBS release model representing advection through a ''failed'' waste package (the first model) may be too conservative; thus a ''failed'' waste package container with multiple perforations may still be an important barrier to radionuclide release

  6. Assessment of Osmotic Pre-Drying Treatment on Drying Rates of Fresh Tomato Fruits

    Directory of Open Access Journals (Sweden)

    P. A. Idah

    2014-06-01

    Full Text Available The aim of this work is to investigate the influence of osmotic pre-drying treatments on drying rates of tomato (Lycopersiconesculentum at various drying temperatures. Fresh Roma tomato fruit samples were sliced to a thickness of 5 mm and the seeds were removed. Weight of 300 g was measured for each of the three replicates and immersed in a hypertonic solution of sucrose of different concentrations 40 and 60 oBrix each held for osmotic duration of 1 and 2 hours, drained for 10 min and then dried at 50, 60, and 70 oC in a mechanical dryer. Control samples were also weighed 300 g per replicate and dried at 50, 60, and 70 oC without pre-drying treatment. The initial moisture content of fresh tomato used was 94.5% (wb. Moisture loss of each sample was monitored and recorded hourly until the product has reached the desired final moisture content (≤ 7%.The data collected were subjected to statistical analysis of variance (ANOVA and Duncan New Multiple range tests (DNMRT to ascertain the level of significance differences between the individual treatments and their interaction at p ≤ 0.05.The results show that at all the drying temperatures used, the control tomato samples exhibited the fastest drying rate with an average of 35.2 g/hr, samples pre-treated at 40 oBrix has an average drying rate of 26.6 g/hr, while samples pre-treated at 60 oBrix has the slowest drying rate of 25.2 g/hr. It was also revealed that samples subjected to 1 hour osmotic time have faster drying rates than those treated for 2 hours osmotic time.

  7. HIGH REPETITION RATE MICROCHIP ER3+,YB3+:YAL3(BO34 DIODE-PUMPED LASER

    Directory of Open Access Journals (Sweden)

    K. N. Gorbachenya

    2012-01-01

    Full Text Available Diode-pumped passively Q-switched microchip Er,Yb:YAl3(BO34 laser for range-finding has been demonstrated. By using a Co2+:MgAl2O4 as a saturable absorber TEM00–mode Q-switched average output power of 315 mW was demonstrated at 1522 nm with pulse duration of 5 ns and pulse energy of 5,25 μJ at a repetition rate of 60 kHz.

  8. The effects of feeding unpredictability and classical conditioning on pre-release training of white-lipped peccary (Mammalia, Tayassuidae.

    Directory of Open Access Journals (Sweden)

    Selene S C Nogueira

    Full Text Available Some authors have suggested that environmental unpredictability, accompanied by some sort of signal for behavioral conditioning, can boost activity or foster exploratory behavior, which may increase post-release success in re-introduction programs. Thus, using white-lipped peccary (Tayassu pecari, a vulnerable Neotropical species, as a model, we evaluated an unpredictable feeding schedule. Associating this with the effect of classical conditioning on behavioral activities, we assessed the inclusion of this approach in pre-release training protocols. The experimental design comprised predictable feeding phases (control phases: C1, C2 and C3 and unpredictable feeding phases (U1- signaled and U2- non-signaled. The animals explored more during the signaled and non-signaled unpredictable phases and during the second control phase (C2 than during the other two predictable phases (C1 and C3. The peccaries also spent less time feeding during the signaled unpredictable phase (U1 and the following control phase (C2 than during the other phases. Moreover, they spent more time in aggressive encounters during U1 than the other experimental phases. However, the animals did not show differences in the time they spent on affiliative interactions or in the body weight change during the different phases. The signaled unpredictability, besides improving foraging behavior, showing a prolonged effect on the next control phase (C2, also increased the competition for food. The signaled feeding unpredictability schedule, mimicking wild conditions by eliciting the expression of naturalistic behaviors in pre-release training, may be essential to fully prepare them for survival in the wild.

  9. The effects of feeding unpredictability and classical conditioning on pre-release training of white-lipped peccary (Mammalia, Tayassuidae).

    Science.gov (United States)

    Nogueira, Selene S C; Abreu, Shauana A; Peregrino, Helderes; Nogueira-Filho, Sérgio L G

    2014-01-01

    Some authors have suggested that environmental unpredictability, accompanied by some sort of signal for behavioral conditioning, can boost activity or foster exploratory behavior, which may increase post-release success in re-introduction programs. Thus, using white-lipped peccary (Tayassu pecari), a vulnerable Neotropical species, as a model, we evaluated an unpredictable feeding schedule. Associating this with the effect of classical conditioning on behavioral activities, we assessed the inclusion of this approach in pre-release training protocols. The experimental design comprised predictable feeding phases (control phases: C1, C2 and C3) and unpredictable feeding phases (U1- signaled and U2- non-signaled). The animals explored more during the signaled and non-signaled unpredictable phases and during the second control phase (C2) than during the other two predictable phases (C1 and C3). The peccaries also spent less time feeding during the signaled unpredictable phase (U1) and the following control phase (C2) than during the other phases. Moreover, they spent more time in aggressive encounters during U1 than the other experimental phases. However, the animals did not show differences in the time they spent on affiliative interactions or in the body weight change during the different phases. The signaled unpredictability, besides improving foraging behavior, showing a prolonged effect on the next control phase (C2), also increased the competition for food. The signaled feeding unpredictability schedule, mimicking wild conditions by eliciting the expression of naturalistic behaviors in pre-release training, may be essential to fully prepare them for survival in the wild.

  10. Estimation of free-hydrocarbon recovery from dual-pump systems

    International Nuclear Information System (INIS)

    Charbeneau, R.J.

    1995-01-01

    Free-product hydrocarbon which floats on the water table may be recovered using single-pump and dual-pump systems. The factors that affect the long-term free-product recovery using dual-pump systems include the free-product thickness as measured in monitoring wells, the ground-water pumping rate, hydrocarbon density and viscosity, and the soil permeability. This paper presents a simple model for prediction of free-product recovery using dual-pump systems. The model predicts the long-term rather than short-term recovery rates, and lends itself to spreadsheet calculations on microcomputers. A particularly simple form arises for cases where the drawdown is small. An application for estimating recovery from a dual-pump system is presented, and limitations of the model are summarized

  11. Concrete volute pumps: technology review and improvement

    Science.gov (United States)

    Prunières, R.; Longatte, F.; Catelan, F. X.; Philippot, J. M.

    2012-11-01

    When pumps need to deliver large water flow rates (typically more than 5 m3.s-1), concrete volute pumps (CVP) offer an interesting alternative to standard vertical wet-pit pumps. One of the major advantages of CVP is its simplicity in terms of design, manufacturability and maintainability. In addition, CVP geometrical arrangement allows to reach high performances in terms of hydraulic and mechanical behaviour. These advantages can be specifically appreciated when such pumps are used in the energy field for Power Plants which need high flow rate and reliability, and can lead to important financial savings over the Plant lifetime compared to vertical wet-pit pumps. Finally, as CVP was for a long time limited to total head rise lower than 30 mWC, it was established through CFD analysis that the addition of guide vanes between the impeller and the volute allows to achieve higher head rise without risk.

  12. Effect of pre operative heart rate on post spinal hypotension in obsteric patients

    International Nuclear Information System (INIS)

    Khan, S.; Zahoor, M.U.; Zaid, A.Y.; Buland, K.

    2010-01-01

    The purpose of the study was to determine the association between of preoperative heart rate and post spinal hypotension in women undergoing cesarean section, Two hundred patients undergoing caesarean were included in the study selected on non probability convenience sampling technique, The patients were divided into two groups depending upon their pre operative heart rate. Spinal anesthesia was administered and number of patients developing hypotension was noted. Among 200 patients, who were included in the study; 112 were placed in group A and 88 were placed in group B depending on mean heart rate of 90 beats per minute or less or 91 beats per minute or more respectively. In group A 14 (11.86%) patients developed hypotension where as in group B 28 (31,82%) patients developed hypotension. Pre operative heart rate is significantly associated with post spinal hypotension in obstetric patients undergoing cesarean section. (author)

  13. Selection of Sampling Pumps Used for Groundwater Monitoring at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Schalla, Ronald; Webber, William D.; Smith, Ronald M.

    2001-11-05

    The variable frequency drive centrifugal submersible pump, Redi-Flo2a made by Grundfosa, was selected for universal application for Hanford Site groundwater monitoring. Specifications for the selected pump and five other pumps were evaluated against current and future Hanford groundwater monitoring performance requirements, and the Redi-Flo2 was selected as the most versatile and applicable for the range of monitoring conditions. The Redi-Flo2 pump distinguished itself from the other pumps considered because of its wide range in output flow rate and its comparatively moderate maintenance and low capital costs. The Redi-Flo2 pump is able to purge a well at a high flow rate and then supply water for sampling at a low flow rate. Groundwater sampling using a low-volume-purging technique (e.g., low flow, minimal purge, no purge, or micropurgea) is planned in the future, eliminating the need for the pump to supply a high-output flow rate. Under those conditions, the Well Wizard bladder pump, manufactured by QED Environmental Systems, Inc., may be the preferred pump because of the lower capital cost.

  14. Effects of Sediment Chemical Properties on Phosphorus Release Rates in the Sediment-Water Interface of the Steppe Wetlands

    Directory of Open Access Journals (Sweden)

    Jing He

    2017-11-01

    Full Text Available Rising temperature causes a process of phosphorus release, which can be characterized well using phosphorus release rates (VP. The objective of the present study was to investigate the major factors affecting sediment phosphorus release rates through a wetland habitat simulation experiment. The results showed that the VP of different wetland sediments were different and changed with the order of W–R (river wetland > W–L (lake wetland > W–M (grassy marsh wetland > W–A (reservoir wetland. The main driving factors which influenced sediment phosphorus flux velocity in the sediment–water interface were sediment B-SO42−, B-MBN and A-MBP content. Path analysis and determination coefficient analysis indicated the standard multiple regression equation for sediment phosphorus release rates in the sediment–water interface, and each main factor was Y = −0.105 + 0.096X1 + 0.275X2 − 0.010X3 (r = 0.416, p < 0.01, n = 144, where Y is sediment phosphorus release rates; X1 is sediment B-SO42− content; X2 is sediment B-MBN; and X3 is sediment A-MBP content. Sediment B-SO42−, B-MBN and A-MBP content and the interaction between them were the main factors affecting sediment phosphorus release rates in the sediment–water interface. Therefore, these results suggest that soil chemical properties and microbial activities likely play an important role in phosphorus release rates in the sediment–water interface. We hope to provide effective scientific management and control methods for relevant environmental protection departments.

  15. Study of brushless fuel pump (improvement of pump and motor parts). 2nd Report. Blushless dendo fuel pump no kento. 2

    Energy Technology Data Exchange (ETDEWEB)

    Mine, K; Takada, S; Tatematsu, M; Takeuchi, H [Aisan Industry Co. Ltd., Aichi (Japan)

    1992-10-01

    A methanol use electrically driven fuel pump was developed as reported in the present report. Mixed fuel of gasoline with alcohol can be handled by a brushless fuel pump which was proposed and improved as reported. The flow rate performance was heightened to 25g/sec by heightening in output power of motor, while the high temperature performance was 17% heightened against the conventional ratio of lowering in flow rate by heightening in vapor jet capacity. Against the corrosiveness of methanol, an in-tank type was applied to the pump, and all its electrically conductive and other mechanical parts were made to be both anti-corrosive and anti-abrasive. It is structurally of a two-stage series turbine type of non-volume form. A sensor method was applied to the motor by confining the miniaturized control circuit of brushless motor in the motor so that the transistor is controlled against the heightening in temperature. The motor is a three-phase half-wave driving motor. Also developed was a fuel supply system which is useful for the mixed fuel covering a range of 100% methanol through 100% gasoline. The present pump is dimensionally interchangeable with the conventional gasoline use one. Its operational life is more than 10000 hours. 3 refs., 17 figs., 1 tab.

  16. Modeling ionospheric pre-reversal enhancement and plasma bubble growth rate using data assimilation

    Science.gov (United States)

    Rajesh, P. K.; Lin, C. C. H.; Chen, C. H.; Matsuo, T.

    2017-12-01

    We report that assimilating total electron content (TEC) into a coupled thermosphere-ionosphere model by using the ensemble Kalman filter results in improved specification and forecast of eastward pre-reversal enhancement (PRE) electric field (E-field). Through data assimilation, the ionospheric plasma density, thermospheric winds, temperature and compositions are adjusted simultaneously. The improvement of dusk-side PRE E-field over the prior state is achieved primarily by intensification of eastward neutral wind. The improved E-field promotes a stronger plasma fountain and deepens the equatorial trough. As a result, the horizontal gradients of Pedersen conductivity and eastward wind are increased due to greater zonal electron density gradient and smaller ion drag at dusk, respectively. Such modifications provide preferable conditions and obtain a strengthened PRE magnitude closer to the observation. The adjustment of PRE E-field is enabled through self-consistent thermosphere and ionosphere coupling processes captured in the model. The assimilative outputs are further utilized to calculate the flux tube integrated Rayleigh-Taylor instability growth rate during March 2015 for investigation of global plasma bubble occurrence. Significant improvements in the calculated growth rates could be achieved because of the improved update of zonal electric field in the data assimilation forecast. The results suggest that realistic estimate or prediction of plasma bubble occurrence could be feasible by taking advantage of the data assimilation approach adopted in this work.

  17. Saltwater Upconing and Decay Beneath a Well Pumping Above an Interface Zone

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Quanlin; Bear, Jacob; Bensabat, Jacob

    2004-04-20

    Saltwater, or brine, underlies fresh water in many aquifers, with a transition zone separating them. Pumping fresh water by wells located above the transition zone produces upconing of the latter, eventually salinizing the pumped water, forcing shut-off. The salinity of the pumped water depends on the pumping rate, on the location of the well's screen, on the fresh water flow regime, and on the difference in density between fresh and salt water, expressed as a dimensionless factor called density difference factor (DDF). Following the well's shut-off, the upconed saltwater mound undergoes decay, tending to return to the pre-pumping regime. In this paper, the upconing-decay processes in an axially symmetrical system are investigated to discover how they are affected by the DDF and by the dispersivities. The code FEAS-Brine, developed for the simulation of coupled density-dependent flow and salt transport, is used. In this code, the flow equation is solved by the Galer:wqkin finite element method (FEM), while the advective-dispersive salt transport equation is solved in the Eulerian-Lagrangian framework. This code does not suffer from the instability constraint on the Peclet number in the vicinity of the pumping well, where advection dominates the salt transport. Simulation results show that upconing is very sensitive to the DDF, which, in our work, is in the range from 0 (for ideal tracer) to 0.2 (for brine). It is shown that for the DDF of 0.025 (for seawater), local upconing occurs only for low iso-salinity surfaces, while those of high salt concentration, practically, do not shift toward the pumping well. For an ideal tracer, all iso-salinity surfaces rise toward the pumping well. For brine, however, only iso-salinity surfaces of very low salinity upcone towards the pumping well. The decay process is lengthy; it takes a long time for the upconed saltwater to migrate back to the original horizontal transition zone prior to pumping. However, the wider

  18. Applications of energy-release-rate techniques to part-through cracks in experimental pressure vessels

    International Nuclear Information System (INIS)

    Bass, B.R.; Bryan, R.H.; Bryson, J.W.; Merkle, J.G.

    1982-01-01

    In nonlinear applications of computational fracture mechanics, energy release rate techniques are used increasingly for computing stress intensity parameters of crack configurations. Recently, deLorenzi used the virtual-crack-extension method to derive an analytical expression for the energy release rate that is better suited for three-dimensional calculations than the well-known J-integral. Certain studies of fracture phenomena, such as pressurized-thermal-shock of cracked structures, require that crack tip parameters be determined for combined thermal and mechanical loads. A method is proposed here that modifies the isothermal formulation of deLorenzi to account for thermal strains in cracked bodies. This combined thermo-mechanical formulation of the energy release rate is valid for general fracture, including nonplanar fracture, and applies to thermo-elastic as well as deformation plasticity material models. Two applications of the technique are described here. In the first, semi-elliptical surface cracks in an experimental test vessel are analyzed under elastic-plastic conditions using the finite element method. The second application is a thick-walled test vessel subjected to combined pressure and thermal shock loadings

  19. On the Ni-Ion release rate from surfaces of binary NiTi shape memory alloys

    Science.gov (United States)

    Ševčíková, Jana; Bártková, Denisa; Goldbergová, Monika; Kuběnová, Monika; Čermák, Jiří; Frenzel, Jan; Weiser, Adam; Dlouhý, Antonín

    2018-01-01

    The study is focused on Ni-ion release rates from NiTi surfaces exposed in the cell culture media and human vascular endothelial cell (HUVEC) culture environments. The NiTi surface layers situated in the depth of 70 μm below a NiTi oxide scale are affected by interactions between the NiTi alloys and the bio-environments. The finding was proved with use of inductively coupled plasma mass spectrometry and electron microscopy experiments. As the exclusive factor controlling the Ni-ion release rates was not only thicknesses of the oxide scale, but also the passivation depth, which was two-fold larger. Our experimental data strongly suggested that some other factors, in addition to the Ni concentration in the oxide scale, admittedly hydrogen soaking deep below the oxide scale, must be taken into account in order to rationalize the concentrations of Ni-ions released into the bio-environments. The suggested role of hydrogen as the surface passivation agent is also in line with the fact that the Ni-ion release rates considerably decrease in NiTi samples that were annealed in controlled hydrogen atmospheres prior to bio-environmental exposures.

  20. Development of novel diclofenac potassium controlled release tablets by wet granulation technique and the effect of co-excipients on in vitro drug release rates.

    Science.gov (United States)

    Shah, Shefaatullah; Khan, Gul Majid; Jan, Syed Umer; Shah, Kifayatullah; Hussain, Abid; Khan, Haroon; Khan, Haroon; Khan, Haroon; Khan, Kamran Ahmad

    2012-01-01

    The aim of the present study was the formulation and evaluation of controlled release polymeric tablets of Diclofenac Potassium by wet granulation method for the release rate, release pattern and the mechanism involved in drug release. Formulations having three grades of polymer Ethocel (7P; 7FP, 10P, 10FP, 100P, 100FP) in several drugs to polymer ratios (10:3 and 10:1) were compressed into tablets using wet granulation method. Co-excipients were added to some selected formulations to investigate their enhancement effect on in vitro drug release patterns. In vitro drug release studies were performed using USP Method-1 (Rotating Basket method) and Phosphate buffer (pH 7.4) was used as a dissolution medium. The similarities and dissimilarities of release profiles of test formulations with reference standard were checked using f2 similarity factor and f1 dissimilarity factor. Mathematical/Kinetic models were employed to determine the release mechanism and drug release kinetics.

  1. Evaluation of olibanum and its resin as rate controlling matrix for controlled release of diclofenac

    OpenAIRE

    Chowdary KPR; Mohapatra P; Murali Krishna M

    2006-01-01

    Olibanum and its resin and carbohydrate fractions were evaluated as rate controlling matrix materials in tablets for controlled release of diclofenac. Diclofenac matrix tablets were formulated employing olibanum and its resin and carbohydrate fractions in different concentrations and the tablets were evaluated for various tablet characters including drug release kinetics and mechanism. Olibanum and its resin component exhibited excellent retarding effect on drug release from the matrix tablet...

  2. The Causes and Prevention Measures of Stuck Pump Phenomenon of Rod-pumped Well in CBM Field

    Science.gov (United States)

    Yonggui, Mei

    2018-02-01

    In the process of CBM field exploitation, in order to realize the drainage equipment to work continuous stably, the article pays attention to study and solve the stuck pump problem, and aim of reducing reservoir damage and lowing production costs. Through coal particles stuck pump experiment and sediment composition analysis, we find out five primary cause of stuck pump phenomenon: sand from coal seam, sediment from ground, iron corrosion, iron scrap caused by eccentric wear, coal cake. According to stuck pump mechanism, the article puts forward 8 measures to prevent stuck pump phenomenon, and the measures are focused on technology optimization, operation management and drainage process control. After 7 years production practice, the yearly stuck pump rate has dropped from 8.9% to 1.2%, and the pump inspection period has prolonged 2 times. The experiment result shows that pure coal particles cannot cause stuck pump, but sand, scrap iron, and iron corrosion are the primary cause of stuck pump. The article study and design the new pipe string structure that the bottom of the pipe string is open. This kind of pipe string applied the sedimentation terminal velocity theory to solve the stuck pump phenomenon, and it can be widely used in CBM drainage development.

  3. Operation of an organic Rankine cycle dependent on pumping flow rates and expander torques

    International Nuclear Information System (INIS)

    Yang, Xufei; Xu, Jinliang; Miao, Zheng; Zou, Jinghuang; Yu, Chao

    2015-01-01

    An ORC (organic Rankine cycle) was developed with R123 as the working fluid. The heat capacity is in ∼100 kW. The match between pump and expander is investigated. Lower pump frequencies (f 10 Hz) adapt low expander torques only, and cause unstable flow and pump cavitation for larger expander torques. Ultra-low expander torques generate sufficiently high vapor superheatings to decrease expander efficiencies. Ultra-high expander torques achieve saturation vapor at the expander inlet, causing liquid droplets induced shock wave to worsen expander performance. An optimal range of expander torques exists to have better expander performance. A liquid subcooling of 20 °C is necessary to avoid pump cavitation. Expander powers and efficiencies show parabola shapes versus expander torques, or vapor superheatings at the expander inlet. The optimal vapor superheating is 13 °C. The cavitation mechanisms and measures to avoid cavitation are analyzed. This paper notes the overestimation of ORC performance by equilibrium thermodynamic analysis. Assumptions should be dependent on experiments. Future studies are suggested on organic fluid flow, heat transfer and energy conversion in various components. - Highlights: • The match between pump and expander is investigated. • A liquid subcooling of 20 °C is needed at pump inlet. • A vapor superheating of 13 °C is necessary at expander inlet. • Cavitation in pumps and expanders are analyzed. • The equilibrium thermodynamics overestimate ORC performances.

  4. Fabrication of an electromagnetic pump with gas circulation

    International Nuclear Information System (INIS)

    Ravoire, J.

    1959-01-01

    This note reports the design and production of a pump aimed at circulating a gas in a closed circuit, and possessing some specific properties (tightness, gas in contact only with glass, operation pressure range, rates, resistance to overpressure). After a description of pump operation principle, the author describes the glassware part of the pump, its electromagnetic and electronic parts. He reports tests performed to assess pump characteristics. Obtained data are graphically presented, as well as a drawing of the pump

  5. A novel osmotic pump-based controlled delivery system consisting of pH-modulated solid dispersion for poorly soluble drug flurbiprofen: in vitro and in vivo evaluation.

    Science.gov (United States)

    Li, Shujuan; Wang, Xiaoyu; Wang, Yingying; Zhao, Qianqian; Zhang, Lina; Yang, Xinggang; Liu, Dandan; Pan, Weisan

    2015-01-01

    In this study, a novel controlled release osmotic pump capsule consisting of pH-modulated solid dispersion for poorly soluble drug flurbiprofen (FP) was developed to improve the solubility and oral bioavailability of FP and to minimize the fluctuation of plasma concentration. The pH-modulated solid dispersion containing FP, Kollidon® 12 PF and Na2CO3 at a weight ratio of 1/4.5/0.02 was prepared using the solvent evaporation method. The osmotic pump capsule was assembled by semi-permeable capsule shell of cellulose acetate (CA) prepared by the perfusion method. Then, the solid dispersion, penetration enhancer, and suspending agents were tableted and filled into the capsule. Central composite design-response surface methodology was used to evaluate the influence of factors on the responses. A second-order polynomial model and a multiple linear model were fitted to correlation coefficient of drug release profile and ultimate cumulative release in 12 h, respectively. The actual response values were in good accordance with the predicted ones. The optimized formulation showed a complete drug delivery and zero-order release rate. Beagle dogs were used to be conducted in the pharmacokinetic study. The in vivo study indicated that the relative bioavailability of the novel osmotic pump system was 133.99% compared with the commercial preparation. The novel controlled delivery system with combination of pH-modulated solid dispersion and osmotic pump system is not only a promising strategy to improve the solubility and oral bioavailability of poorly soluble ionizable drugs but also an effective way to reduce dosing frequency and minimize the plasma fluctuation.

  6. Generation of nanosecond laser pulses at a 2.2-MHz repetition rate by a cw diode-pumped passively Q-switched Nd3+:YVO4 laser

    International Nuclear Information System (INIS)

    Nghia, Nguyen T; Hao, Nguyen V; Orlovich, Valentin A; Hung, Nguyen D

    2011-01-01

    We report a new configuration of a high-repetition rate nanosecond laser based on a semiconductor saturable absorber mirror (SESAM). The SESAM is conventional technical solution for passive mode-locking at 1064 nm and simultaneously used as a highly reflecting mirror and a saturable absorber in a high-Q and short cavity of a cw diode-end-pumped a-cut Nd 3+ :YVO 4 laser. Two laser beams are coupled out from the cavity using an intracavity low-reflection thin splitter. The laser characteristics are investigated as functions of pump and resonator parameters. Using a 1.8-W cw pump laser diode at 808 nm, the passively Q-switched SESAMbased laser generates 22-ns pulses with an average power of 275 mW at a pulse repetition rate of 2250 kHz.

  7. Setting accelerated dissolution test for PLGA microspheres containing peptide, investigation of critical parameters affecting drug release rate and mechanism.

    Science.gov (United States)

    Tomic, I; Vidis-Millward, A; Mueller-Zsigmondy, M; Cardot, J-M

    2016-05-30

    The objective of this study was development of accelerated in vitro release method for peptide loaded PLGA microspheres using flow-through apparatus and assessment of the effect of dissolution parameters (pH, temperature, medium composition) on drug release rate and mechanism. Accelerated release conditions were set as pH 2 and 45°C, in phosphate buffer saline (PBS) 0.02M. When the pH was changed from 2 to 4, diffusion controlled phases (burst and lag) were not affected, while release rate during erosion phase decreased two-fold due to slower ester bonds hydrolyses. Decreasing temperature from 45°C to 40°C, release rate showed three-fold deceleration without significant change in release mechanism. Effect of medium composition on drug release was tested in PBS 0.01M (200 mOsm/kg) and PBS 0.01M with glucose (380 mOsm/kg). Buffer concentration significantly affected drug release rate and mechanism due to the change in osmotic pressure, while ionic strength did not have any effect on peptide release. Furthermore, dialysis sac and sample-and-separate techniques were used, in order to evaluate significance of dissolution technique choice on the release process. After fitting obtained data to different mathematical models, flow-through method was confirmed as the most appropriate for accelerated in vitro dissolution testing for a given formulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Optically pumped laser systems

    International Nuclear Information System (INIS)

    DeMaria, A.J.; Mack, M.E.

    1975-01-01

    Laser systems which are pumped by an electric discharge formed in a gas are disclosed. The discharge is in the form of a vortex stabilized electric arc which is triggered with an auxiliary energy source. At high enough repetition rates residual ionization between successive pulses contributes to the pulse stabilization. The arc and the gain medium are positioned inside an optical pumping cavity where light from the arc is coupled directly into the gain medium

  9. Quantitative assessment of haemolysis secondary to modern infusion pumps.

    Science.gov (United States)

    Poder, T G; Boileau, J-C; Lafrenière, R; Thibault, L; Carrier, N; de Grandmont, M-J; Beauregard, P

    2017-04-01

    Although most studies have shown that little haemolysis is induced by infusion pumps, there are some notable exceptions. Only limited data are available on the actual infusion pumps that are most used in hospitals in Quebec and elsewhere, namely, the Infusomat ® Space (peristaltic), Plum A+™ (piston) and Colleague ® CXE (shuttle) pumps. Haemolysis and potassium levels were compared before and after the use of the three different infusion pumps. Using 135 units of packed red blood cells (RBCs) aged from 10 to 28 days, 27 measurements were taken for each pump at various flow rates (30, 60, 150, 300 and 450 ml/h) and were compared with measurements taken before using the pumps. The range of flow rates was chosen to cover those of paediatric and adult transfusions. The shuttle- and piston-type pumps resulted in low haemolysis levels. The peristaltic-type pump produced significantly more haemolysis, which worsened at low flow rates, but the absolute value of haemolysis remained within the range recommended by the regulatory agencies in North America and Europe. Approximately two-thirds of the haemolysis produced by the peristaltic-type pump seemed to be secondary to the use of an antisiphon valve (ASV) on the transfusion line recommended by the manufacturer. Potassium levels did not increase with the use of the pumps. Modern infusion pumps widely used in hospitals in Quebec and elsewhere produce non-threatening levels of haemolysis during the transfusion of packed RBCs aged from 10 to 28 days. ASVs appear to induce additional haemolysis, and we do not recommend using them for blood transfusion. © 2017 International Society of Blood Transfusion.

  10. Thermal fracture and pump limit of Nd: glass

    International Nuclear Information System (INIS)

    Wang Mingzhe; Ma Wen; Tan Jichun; Zhang Yongliang; Li Mingzhong; Jing Feng

    2011-01-01

    Based on published fracture experiments and 3D transient finite-element analyses, and taking the first principal stress as the criterion and the Griffith crack theory to determine the critical fracture stress, a Weibull statistical model is established to predict the fracture possibility of Nd: glass with certain pump parameters. Other issues which limit the pump power are also presented. The results show that the fracture limit of laser medium depends on the optical polishing technology. For a short pulse and high energy Nd: glass laser, taking America's polishing technology in the 1990s as reference,the pump saturation limits the pump power to 18 kW/cm 2 when the repetition rate is lower than 1 Hz, while the thermal fracture limits the pump power when the repetition rate is higher than 10 Hz. (authors)

  11. Comodulation masking release in bit-rate reduction systems

    DEFF Research Database (Denmark)

    Vestergaard, Martin David; Rasmussen, Karsten Bo; Poulsen, Torben

    1999-01-01

    It has been suggested that the level dependence of the upper masking slope be utilized in perceptual models in bit-rate reduction systems. However, comodulation masking release (CMR) phenomena lead to a reduction of the masking effect when a masker and a probe signal are amplitude modulated...... with the same frequency. In bit-rate reduction systems the masker would be the audio signal and the probe signal would represent the quantization noise. Masking curves have been determined for sinusoids and 1-Bark-wide noise maskers in order to investigate the risk of CMR, when quantizing depths are fixed...... in accordance with psycho-acoustical principles. Masker frequencies of 500 Hz, 1 kHz, and 2 kHz have been investigated, and the masking of pure tone probes has been determined in the first four 1/3 octaves above the masker. Modulation frequencies between 6 and 20 Hz were used with a modulation depth of 0...

  12. Method of starting internal pumps of a nuclear reactor

    International Nuclear Information System (INIS)

    Kumagami, Shoji.

    1985-01-01

    Purpose: To reduce the noise effects by decreasing the invading current into the main line upon starting an internal pump type nuclear reactor adapted to forcively recycle the reactor water by a plurality of internal pumps. Method: A plurality of internal pumps are divided into several groups and, upon starting pumps belonging to the individual unit group, the starting instances for the respective pumps are deviated to reduce the surges applied to the main line and suppress the invading current lower to reduce the earth noises. As a result, effects caused to other devices or equipments can be moderated to improve the reliability. Furthermore, by actuating the respective pumps on every group units in a starting pattern along the orthogonal line, flow rate distribution in the reactor can be balanced. Then, the instability region during low rotation of pumps, that is, instability of the flow rate near the resonance frequency can be decreased. (Kawakami, Y.)

  13. User friendliness, efficiency & spray quality of stirrup pumps versus hand compression pumps for indoor residual spraying.

    Science.gov (United States)

    Kumar, Vijay; Kesari, Shreekant; Chowdhury, Rajib; Kumar, Sanjiv; Sinha, Gunjan; Hussain, Saddam; Huda, M Mamun; Kroeger, Axel; Das, Pradeep

    2013-01-01

    Indoor residual spraying (IRS) is a proven tool to reduce visceral leishmaniasis vectors in endemic villages. In India IRS is being done with stirrup pumps, whereas Nepal, Bangladesh, and other countries use compression pumps. The present study was conducted with the objectives to compare the efficiency, cost and user friendliness of stirrup and compression pumps. The study was carried out in Gorigawan village of the Vaishali district in north Bihar and included a total population of 3259 inhabitants in 605 households. Spraying with 50 per cent DDT was done by two teams with 6 persons per team under the supervision of investigators over 5 days with each type of pump (10 days in total using 2 stirrup pumps and 3 compression pumps) by the same sprayers in an alternate way. The spraying technique was observed using an observation check list, the number of houses and room surfaces sprayed was recorded and an interview with sprayers on their satisfaction with the two types of pumps was conducted. On average, 65 houses were covered per day with the compression pump and 56 houses were covered with the stirrup pump. The surface area sprayed per squad per day was higher for the compression pump (4636 m²) than for the stirrup pump (4102 m²). Observation showed that it was easy to maintain the spray swath with the compression pump but very difficult with the stirrup pump. The wastage of insecticide suspension was negligible for the compression pump but high for the stirrup pump. The compression pump was found to be more user friendly due to its lower weight, easier to operate, lower operation cost, higher safety and better efficiency in terms of discharge rate and higher area coverage than the stirrup pump.

  14. Prospects for a wind pump industry in Sri Lanka

    International Nuclear Information System (INIS)

    Fernando, S.

    1991-01-01

    Since 1977 considerable effort has been made in Sri Lanka to develop and disseminate wind pumping systems primarily in the small-scale agricultural sector in the island's dry zone. Through close cooperation with the Consultancy Services Wind Energy Developing Countries (CWD) in the Netherlands this programme has been successful in developing the necessary hardware but the broad objective of promoting wide spread use of wind pumping in Sri Lanka is yet to materialize. In analyzing probable reasons for this, the paper highlights that the basic arguments underlying the origin of the project in 1976, such as foreign exchange savings and local industrial development, became irrelevant to the post 1977 political and economic policies of the new government. Thus, the general economic framework adopted in Sri Lanka since 1977 does not seem to provide the necessary pre-conditions for development of a local industry for wind pumps. Due to this reason and the fact that kerosene oil used in conventional agriculturla pumps is subsidized, the ability of wind pumps to compete in the wind pump market seems highly constrained. It is concluded that under such conditions the prospects for the manufacturing and marketing of wind pumps on an industrial scale are not very favourable

  15. Design of a high-pressure circulating pump for viscous liquids.

    Science.gov (United States)

    Seifried, Bernhard; Temelli, Feral

    2009-07-01

    The design of a reciprocating dual action piston pump capable of circulating viscous fluids at pressures of up to 34 MPa (5000 psi) and temperatures up to 80 degrees C is described. The piston of this pump is driven by a pair of solenoids energized alternatively by a 12 V direct current power supply controlled by an electronic controller facilitating continuously adjustable flow rates. The body of this seal-less pump is constructed using off-the-shelf parts eliminating the need for custom made parts. Both the electronic controller and the pump can be assembled relatively easily. Pump performance has been evaluated at room temperature (22 degrees C) and atmospheric pressure using liquids with low and moderately high viscosities, such as ethanol and corn oil, respectively. At ambient conditions, the pump delivered continuous flow of ethanol and corn oil at a flow rate of up to 170 and 17 cm3/min, respectively. For pumping viscous fluids comparable to corn oil, an optimum reciprocation frequency was ascertained to maximize flow rate. For low viscosity liquids such as ethanol, a linear relationship between the flow rate and reciprocation frequency was determined up to the maximum reciprocation frequency of the pump. Since its fabrication, the pump has been used in our laboratory for circulating triglycerides in contact with supercritical carbon dioxide at pressures of up to 25 MPa (3600 psi) and temperatures up to 70 degrees C on a daily basis for a total of more than 1500 h of operation functioning trouble free.

  16. High efficiency, variable geometry, centrifugal cryogenic pump

    International Nuclear Information System (INIS)

    Forsha, M.D.; Nichols, K.E.; Beale, C.A.

    1994-01-01

    A centrifugal cryogenic pump has been developed which has a basic design that is rugged and reliable with variable speed and variable geometry features that achieve high pump efficiency over a wide range of head-flow conditions. The pump uses a sealless design and rolling element bearings to achieve high reliability and the ruggedness to withstand liquid-vapor slugging. The pump can meet a wide range of variable head, off-design flow requirements and maintain design point efficiency by adjusting the pump speed. The pump also has features that allow the impeller and diffuser blade heights to be adjusted. The adjustable height blades were intended to enhance the pump efficiency when it is operating at constant head, off-design flow rates. For small pumps, the adjustable height blades are not recommended. For larger pumps, they could provide off-design efficiency improvements. This pump was developed for supercritical helium service, but the design is well suited to any cryogenic application where high efficiency is required over a wide range of head-flow conditions

  17. Quality-improvement analytics for intravenous infusion pumps.

    Science.gov (United States)

    Skledar, Susan J; Niccolai, Cynthia S; Schilling, Dennis; Costello, Susan; Mininni, Nicolette; Ervin, Kelly; Urban, Alana

    2013-04-15

    The implementation of a smart-pump continuous quality-improvement (CQI) program across a large health system is described, with an emphasis on key metrics for outcomes analyses and program refinement. Three years ago, the University of Pittsburgh Medical Center health system launched a CQI initiative to help ensure the safe use of 6000 smart pumps in its 14 inpatient facilities. A centralized team led by pharmacists is responsible for the retrieval and interpretation of smart-pump data, which is continuously transmitted to a main server. CQI findings are regularly posted on the health system's interdisciplinary intranet. Monitored metrics include rates of compliance with preprogrammed infusion limits, the top 20 drugs involved in alerts, drugs associated with alert-override rates of ≥90%, numbers of alerts by infusion type, nurse responses to alerts, and alert rate per drug library update. Based on the collected CQI data and site-specific requests, four systemwide updates of the smart-pump drug library were performed during the first 18 months of the program, reducing "nuisance alerts" by about 10% per update cycle and enabling targeted interventions to reduce rapid-infusion errors, other adverse drug events (ADEs), and pump-programming workarounds. Over one 12-month period, bedside alerts prompted nurses to reprogram or cancel continuous infusions an average of 400 times per month, potentially averting i.v. medication ADEs. A smart-pump CQI program is an effective tool for enhancing the safety of i.v. medication administration. The ongoing refinement of the drug library through the development and implementation of key interventions promotes the growth and sustainability of the smart-pump initiative systemwide.

  18. Synchronization modulation of Na/K pumps on Xenopus oocytes

    Science.gov (United States)

    Liang, Pengfei; Mast, Jason; Chen, Wei

    We developed a new technique named synchronization modulation to electrically synchronize and modulate the Na/K pump molecules by a specially designed oscillating electric field. This technique is based on the theory of energy-trap in quantum physics as well as the concept of electronic synchrotron accelerator. As a result, the Na-transports are all entrapped into the positive half-cycle of the applied electric field and consequently, all of the K-transports are entrapped into the negative half cycle of the field. To demonstrate the process of the pump synchronization and modulation, we use Xenopus oocytes as a platform and introduce two-electrode whole-cell voltage clamp in measurement of pump current. Practically, we first synchronize the pump molecules running at the same pace (rate and phase) by a specially designed oscillation electric field. Then, we carefully maintain the pump synchronization status and gradually change the field frequency (decrease and increase) to modulate the pump molecules to newer pumping rate. The result shows a separation of the inward K current from the outward Na current, and about 10 time increase of the total (inward plus outward) pump current from the net outward current from the random paced pump molecules. Also, the ratio of the modulated total pump current with synchronized total pump current is consistent with the ratio of their field frequencies.

  19. Seminar on heat pump research and applications: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Steele, R.V. Jr. (ed.)

    1984-11-01

    This volume is a compilation of papers prepared by speakers at a seminar on heat pumps. The seminar was organized by the Electric Power Research Institute (EPRI) in cooperation with Louisiana Power and Light Company and New Orleans Public Service, Inc. The seminar's purpose was to inform utility managers and engineers of the most recent developments in residential heat pump technology and applications. Statements by invited panelists on the outlook for heat pump technology are also included. The speakers, who represented key organizations in the heat pump area, including utilities, industry associations, manufacturers, independent research institutes, government, and EPRI, addressed the following topics: status of heat pump research and development, heat pump testing and rating; field monitoring of heat pumps; heat pump water heaters; heat pump reliability; and marketing programs for pumps. All papers, total of sixteen have been processed for inclusion in the Energy Data Base.

  20. Diaphragm Pump With Resonant Piezoelectric Drive

    Science.gov (United States)

    Izenson, Michael G.; Kline-Schoder, Robert J.; Shimko, Martin A.

    2007-01-01

    A diaphragm pump driven by a piezoelectric actuator is undergoing development. This pump is intended to be a prototype of lightweight, highly reliable pumps for circulating cooling liquids in protective garments and high-power electronic circuits, and perhaps for some medical applications. The pump would be highly reliable because it would contain no sliding seals or bearings that could wear, the only parts subject to wear would be two check valves, and the diaphragm and other flexing parts could be designed, by use of proven methods, for extremely long life. Because the pump would be capable of a large volumetric flow rate and would have only a small dead volume, its operation would not be disrupted by ingestion of gas, and it could be started reliably under all conditions. The prior art includes a number piezoelectrically actuated diaphragm pumps. Because of the smallness of the motions of piezoelectric actuators (typical maximum strains only about 0.001), the volumetric flow rates of those pumps are much too small for typical cooling applications. In the pump now undergoing development, mechanical resonance would be utilized to amplify the motion generated by the piezoelectric actuator and thereby multiply the volumetric flow rate. The prime mover in this pump would be a stack of piezoelectric ceramic actuators, one end of which would be connected to a spring that would be part of a spring-and-mass resonator structure. The mass part of the resonator structure would include the pump diaphragm (see Figure 1). Contraction of the spring would draw the diaphragm to the left, causing the volume of the fluid chamber to increase and thereby causing fluid to flow into the chamber. Subsequent expansion of the spring would push the diaphragm to the right, causing the volume of the fluid chamber to decrease, and thereby expelling fluid from the chamber. The fluid would enter and leave the chamber through check valves. The piezoelectric stack would be driven electrically to

  1. Standardised classification of pre-release development in male-brooding pipefish, seahorses, and seadragons (Family Syngnathidae)

    Science.gov (United States)

    2012-01-01

    Background Members of the family Syngnathidae share a unique reproductive mode termed male pregnancy. Males carry eggs in specialised brooding structures for several weeks and release free-swimming offspring. Here we describe a systematic investigation of pre-release development in syngnathid fishes, reviewing available data for 17 species distributed across the family. This work is complemented by in-depth examinations of the straight-nosed pipefish Nerophis ophidion, the black-striped pipefish Syngnathus abaster, and the potbellied seahorse Hippocampus abdominalis. Results We propose a standardised classification of early syngnathid development that extends from the activation of the egg to the release of newborn. The classification consists of four developmental periods – early embryogenesis, eye development, snout formation, and juvenile – which are further divided into 11 stages. Stages are characterised by morphological traits that are easily visible in live and preserved specimens using incident-light microscopy. Conclusions Our classification is derived from examinations of species representing the full range of brooding-structure complexity found in the Syngnathidae, including tail-brooding as well as trunk-brooding species, which represent independent evolutionary lineages. We chose conspicuous common traits as diagnostic features of stages to allow for rapid and consistent staging of embryos and larvae across the entire family. In view of the growing interest in the biology of the Syngnathidae, we believe that the classification proposed here will prove useful for a wide range of studies on the unique reproductive biology of these male-brooding fish. PMID:23273265

  2. Standardised classification of pre-release development in male-brooding pipefish, seahorses, and seadragons (Family Syngnathidae

    Directory of Open Access Journals (Sweden)

    Sommer Stefan

    2012-12-01

    Full Text Available Abstract Background Members of the family Syngnathidae share a unique reproductive mode termed male pregnancy. Males carry eggs in specialised brooding structures for several weeks and release free-swimming offspring. Here we describe a systematic investigation of pre-release development in syngnathid fishes, reviewing available data for 17 species distributed across the family. This work is complemented by in-depth examinations of the straight-nosed pipefish Nerophis ophidion, the black-striped pipefish Syngnathus abaster, and the potbellied seahorse Hippocampus abdominalis. Results We propose a standardised classification of early syngnathid development that extends from the activation of the egg to the release of newborn. The classification consists of four developmental periods – early embryogenesis, eye development, snout formation, and juvenile – which are further divided into 11 stages. Stages are characterised by morphological traits that are easily visible in live and preserved specimens using incident-light microscopy. Conclusions Our classification is derived from examinations of species representing the full range of brooding-structure complexity found in the Syngnathidae, including tail-brooding as well as trunk-brooding species, which represent independent evolutionary lineages. We chose conspicuous common traits as diagnostic features of stages to allow for rapid and consistent staging of embryos and larvae across the entire family. In view of the growing interest in the biology of the Syngnathidae, we believe that the classification proposed here will prove useful for a wide range of studies on the unique reproductive biology of these male-brooding fish.

  3. Quantification of Kinetic Rate Law Parameters of Uranium Release from Sodium Autunite as a Function of Aqueous Bicarbonate Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Gudavalli, Ravi; Katsenovich, Yelena; Wellman, Dawn M.; Lagos, Leonel; Tansel, Berrin

    2013-09-05

    ABSTRACT: Hydrogen carbonate is one of the most significant components within the uranium geochemical cycle. In aqueous solutions, hydrogen carbonate forms strong complexes with uranium. As such, aqueous bicarbonate may significantly increase the rate of uranium release from uranium minerals. Quantifying the relationship of aqueous hydrogen carbonate solutions to the rate of uranium release during dissolution is critical to understanding the long-term fate of uranium within the environment. Single-pass flow-through (SPTF) experiments were conducted to estimate the rate of uranium release from Na meta-autunite as a function of bicarbonate solutions (0.0005-0.003 M) under the pH range of 6-11 and temperatures of 5-60oC. Consistent with the results of previous investigation, the rate of uranium release from sodium autunite exhibited minimal dependency on temperature; but were strongly dependent on pH and increasing concentrations of bicarbonate solutions. Most notably at pH 7, the rate of uranium release exhibited 370 fold increases relative to the rate of uranium release in the absence of bicarbonate. However, the effect of increasing concentrations of bicarbonate solutions on the release of uranium was significantly less under higher pH conditions. It is postulated that at high pH values, surface sites are saturated with carbonate, thus the addition of more bicarbonate would have less effect on uranium release. Results indicate the activation energies were unaffected by temperature and bicarbonate concentration variations, but were strongly dependent on pH conditions. As pH increased from 6 to 11, activation energy values were observed to decrease from 29.94 kJ mol-1 to 13.07 kJ mol-1. The calculated activation energies suggest a surface controlled dissolution mechanism.

  4. Numerical analysis of the flow field in the pump chamber of a centrifugal pump with back blades

    International Nuclear Information System (INIS)

    Cao, L; Wang, Z W; Luo, Y Y; Liu, M

    2013-01-01

    Black blade is frequently used as a non-contact seal structure in centrifugal pumps transporting solid-liquid two-phase flow. However, it will disturb the flow in the pump and affect the pump performance. Numerical simulation for 3D turbulence in whole flow passage of a centrifugal pump with back blades was carried out based on RANS method, with SST k-ω turbulence model and SIMPLEC algorithm. Calculation for a similar pump without back blades was also carried out as a comparison. Boundary condition was improved due to the existence of back blade. The influence of back blades on the flow field was analysed qualitatively for three typical conditions. Meanwhile the leakage rate was calculated for several conditions and the effect of back blades was discussed. According to the results, compared with the condition without back blades, it could be seen that back blade apparently changed the flow state in the front chamber, improved near the front shroud and worsened near the pump cover. Velocity was increased and more fluid, which flowed into the front chamber from the pump cover side, flowed back to the spiral casing from the impeller shroud side. With the increase of discharge, the absolute value of leakage rate first went up and then dropped, as a consequence of the combination of two factors, discharge and differential pressure between the impeller outlet and inlet. The seal effect of back blades is most obvious under small discharge condition, and the leakage loss diminished as discharge increased

  5. Variable temperature effects on release rates of readily soluble nuclides

    International Nuclear Information System (INIS)

    Kim, C.-L.; Light, W.B.; Lee, W.W.-L.; Chambre, P.L.; Pigford, T.H.

    1988-09-01

    In this paper we study the effect of temperature on the release rate of readily soluble nuclides, as affected by a time-temperature dependent diffusion coefficient. In this analysis ground water fills the voids in the waste package at t = 0 and one percent of the inventories of cesium and iodine are immediately dissolved into the void water. Mass transfer resistance of partly failed container and cladding is conservatively neglected. The nuclides move through the void space into the surrounding rock under a concentration gradient. We use an analytic solution to compute the nuclide concentration in the gap or void, and the mass flux rate into the porous rock. 8 refs., 4 figs

  6. Evaluation of fuel release rate and mechanism tests under RBCB conditions

    International Nuclear Information System (INIS)

    Adamson, M.G.

    1981-09-01

    This task includes theoretical evaluation of fuel/fission product release behavior from failed LMFBR fuel elements as well as an on-going experimental investigation of the mechanism of oxide fuel dispersal into flowing liquid sodium. The primary objectives of this work are to develop a fuel source term that can be used in predictive models for primary heat transfer system contamination and to understand the separate influences of important system variables (such as flow rate, oxygen impurity level) on this source term. The present report is written in two parts: the first, in condensed form, is an updated evaluation of fuel (U,Pu) and fission product release data, and the second describes the current status of supporting experimental work at General Electric's Vallecitos Laboratory

  7. LOX/LH2 vane pump for auxiliary propulsion systems

    Science.gov (United States)

    Hemminger, J. A.; Ulbricht, T. E.

    1985-01-01

    Positive displacement pumps offer potential efficiency advantages over centrifugal pumps for future low thrust space missions. Low flow rate applications, such as space station auxiliary propulsion or dedicated low thrust orbiter transfer vehicles, are typical of missions where low flow and high head rise challenge centrifugal pumps. The positive displacement vane pump for pumping of LOX and LH2 is investigated. This effort has included: (1) a testing program in which pump performance was investigated for differing pump clearances and for differing pump materials while pumping LN2, LOX, and LH2; and (2) an analysis effort, in which a comprehensive pump performance analysis computer code was developed and exercised. An overview of the theoretical framework of the performance analysis computer code is presented, along with a summary of analysis results. Experimental results are presented for pump operating in liquid nitrogen. Included are data on the effects on pump performance of pump clearance, speed, and pressure rise. Pump suction performance is also presented.

  8. Low-voltage electroosmotic pumping using polyethylene terephthalate track-etched membrane

    Energy Technology Data Exchange (ETDEWEB)

    Wang Ceming; Wang Lin [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xue Jianming, E-mail: jmxue@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Center for Applied Physics and Technology, Peking University, Beijing 100871 (China)

    2012-09-01

    We present experimental investigations of electroosmotic (EO) pumping using polyethylene terephthalate (PET) track-etched membrane at a low applied voltage. An EO pump based on PET track-etched membrane has been designed and fabricated. Pumping performance of the device is experimentally studied in terms of flow rate as a function of applied voltage and KCl aqueous concentration. The PET track-etched membrane EO pump can generate flow rates on the order of 10 {mu}l min{sup -1} cm{sup -2} at several applied volts. The measured flow rate tends to decrease with increasing KCl aqueous concentration. In addition, we study the EO flow in cylindrical nanopore with use of a continuum model, composed of Nernst Planck equations, Poisson equation and Navier Stokes equations.

  9. Innovative application of air ejector as a pump for continuous air monitors

    International Nuclear Information System (INIS)

    Dhanasekaran, A.; Ajoy, K.C.; Santhanam, R.; Rajagopal, V.; Jose, M.T.

    2016-01-01

    Workplace monitoring, one of the key components of the radiation protection program is generally carried out by means of instruments installed permanently in respective areas or through portable air sampling instruments. Continuous air monitor (CAM) is one such monitor that constantly monitors the radionuclide concentration in air and triggers alarm as and when the air concentration goes above the pre-set levels. Conventional CAM system has a filter head, detector, display unit and a pump as four major parts. Pump may be either rotary vane or a vibrating diaphragm which are electrically driven using motors. Air lift pumps using ejectors are widely used where pump reliability and low maintenance are required, and where corrosive, abrasive, or radioactive fluids are handled. Since ejectors are uncomplicated alternative to vacuum pumps, an attempt was made to use the same as a pump for conventional CAMs. An ejector based sampling set up was made, tested and the results are represented in this paper

  10. Unexpectedly high catch-and-release rates in European marine recreational fisheries: implications for science and management

    DEFF Research Database (Denmark)

    Ferter, Keno; Weltersbach, Marc Simon; Strehlow, Harry Vincent

    2013-01-01

    Unexpectedly high catch-and-release rates in European marine recreational fisheries: implications for science and management. – ICES Journal of Marine Science, 70: .While catch-and-release (C&R) is a well-known practice in several European freshwater recreational fisheries, studies on the magnitu...

  11. Magnetic heat pumping near room temperature

    Science.gov (United States)

    Brown, G. V.

    1976-01-01

    It is shown that magnetic heat pumping can be made practical at room temperature by using a ferromagnetic material with a Curie point at or near operating temperature and an appropriate regenerative thermodynamic cycle. Measurements are performed which show that gadolinium is a resonable working material and it is found that the application of a 7-T magnetic field to gadolinium at the Curie point (293 K) causes a heat release of 4 kJ/kg under isothermal conditions or a temperature rise of 14 K under adiabatic conditions. A regeneration technique can be used to lift the load of the lattice and electronic heat capacities off the magnetic system in order to span a reasonable temperature difference and to pump as much entropy per cycle as possible

  12. P-Q characteristic of the electromagnetic pump with the flow rate of 60 l/min

    International Nuclear Information System (INIS)

    Kim, Hee Reyoun; KIm, Jong Man; Cha, Jae Eun; Choi, Jong Hyun; Nam, Ho Yoon

    2005-01-01

    In general, an EM pump has been employed to circulate electrically conductive liquids like molten metals by Lorentz force generated from the magnetic field and its perpendicular current. Especially, at the Liquid Metal Reactor (LMR) which uses liquid sodium with high electrical conductivity as a coolant, an EM pump is noticed due to advantages over mechanical pump such as no rotating part, no noise and simplicity. In the present study, the EM pump of a pilot annular linear induction type with the flowrate of 60 l/min is designed by using electrical equivalent circuit method that is applied to linear induction machines. The designed pump is manufactured by consideration of the requirements of material and function in high temperature and sodium environments. Experimental characterization is carried out according to input currents and frequency. And compared analyses between theoretical prediction and experimental results are performed

  13. A Methodology for the Optimization of Flow Rate Injection to Looped Water Distribution Networks through Multiple Pumping Stations

    Directory of Open Access Journals (Sweden)

    Christian León-Celi

    2016-12-01

    Full Text Available The optimal function of a water distribution network is reached when the consumer demands are satisfied using the lowest quantity of energy, maintaining the minimal pressure required at the same time. One way to achieve this is through optimization of flow rate injection based on the use of the setpoint curve concept. In order to obtain that, a methodology is proposed. It allows for the assessment of the flow rate and pressure head that each pumping station has to provide for the proper functioning of the network while the minimum power consumption is kept. The methodology can be addressed in two ways: the discrete method and the continuous method. In the first method, a finite set of combinations is evaluated between pumping stations. In the continuous method, the search for the optimal solution is performed using optimization algorithms. In this paper, Hooke–Jeeves and Nelder–Mead algorithms are used. Both the hydraulics and the objective function used by the optimization are solved through EPANET and its Toolkit. Two case studies are evaluated, and the results of the application of the different methods are discussed.

  14. Pump-and-treat is not the only solution to aquifer remediation

    International Nuclear Information System (INIS)

    Odermatt, J.R.

    1994-01-01

    The Environmental Protection Agency (EPA) recently surveyed remediation technologies used at petroleum-contaminated sites in 22 states. About 96 percent of underground storage tank (UST) corrective action sites used some form of pump-and-treat technology to remediate contaminated groundwater. However, using only pump-and-treat technology is not a cost-effective approach to aquifer remediation. Pump-and-treat may be more appropriate for containing plumes or for use in initial emergency response actions at sites and massive NAPL releases to groundwater. As of 1990, 68 percent of Superfund records of decision selected pump-and-treat as the final remedy for aquifer remediation. However, of 13 sites where the remedial alternative objective was to restore the aquifer to health-based levels, only one pump-and-treat method has succeeded. Except in cases where human health and the environment are threatened, long-term active technologies, such as pump-and-treat, may not be warranted. Groundwater monitoring and possible wellhead treatment may be perceived as time-consuming processes; however, at many sites, this long-term approach may be far less costly and just as effective as other long-term strategies based on exclusive use of pump-and-treat technology

  15. On-line monitoring of main coolant pump seals

    International Nuclear Information System (INIS)

    Stevens, D.M.; Spencer, J.W.; Morris, D.J.; Glass, S.W.; Sommerfield, G.A.; Harrison, D.

    1984-06-01

    The Babcock and Wilcox Company has developed and implemented a Reactor Coolant Pump Monitoring and Diagnostic System (RCPM and DS). The system has been installed at Toledo Edison Company's Davis-Besse Nuclear Power Station Unit 1. The RCPM and PS continuously monitors a number of indicators of pump performance and notifies the plant operator of out-of-tolerance conditions or pump performance trending toward out-of-tolerance conditions. Pump seal parameters being monitored include pump internal pressures, temperatures, and flow rates. Rotordynamic performanvce and plant operating conditions are also measured with a variety of dynamic sensors. This paper describes the implementation of the system and the results of on-line monitoring of four RC pumps

  16. Study of Peak Expiratory Flow Rate as the Assessment of Lung Function in Occupationally Exposed Petrol Pump Workers of Western Maharashtra

    Directory of Open Access Journals (Sweden)

    Patil Smita V

    2016-04-01

    Full Text Available Background: Fast urbanization trends, rapid industrial growth, globalization, and poor environmental conditions at work places have created a lot of healthrelated issues. Aim and Objectives: The aim of this study is to investigate Peak Expiratory Flow Rate (PEFR as the assessment of lung function in occupationally exposed petrol pump workers and also check whether PEFR increases or decreases with duration of exposure. Material and Methods: The study was conducted on 60 male petrol pump workers between age group of 20-40 years who were working as petrol filling attendants for more than one year from western Maharashtra. 50 normal healthy males with same socioeconomic status were chosen as controls to find out the effect of occupational exposure to petroleum product on PEFR as the assessment of lung function tests. Petrol pump workers were divided into three groups based on their duration of exposure i.e. 1- 5 yrs, 6- 10 yrs and more than 11 years. PEFR of petrol pump workers and control was measured by using a Mini Wright peak flow meter which is a portable device for measuring ventilator functions. Comparisons was done using unpaired t-test for 2 groups comparisons and one way ANOVAfor multiple groups of exposures. Results: The PEFR was significantly lower decrease (p=0.001 around petrol pump workers (389.17 as compared to control (534.2. As year of exposure increased mean value of PEFR was significantly decreased from 452.17, 378.00 and 283.64 respectively in petrol pump workers. Conclusion: The results suggested that respiratory functions i.e. PEFR of occupationally exposed petrol pump workers are significantly reduced as compared to controls, also PEFR is significantly reduced with increase in the duration of exposure.

  17. Laser pumped lasers for isotope separation

    International Nuclear Information System (INIS)

    Fry, S.M.

    1976-01-01

    A study of the isotope separation laser requirements reveals that high pressure polyatomic molecular gas laser pumped lasers can attain the necessary characteristics including tunability, energy output, pulse width, and repetition rate. The results of a search, made for molecules meeting the appropriate requirements for one of several pump schemes utilizing a CO 2 laser and with output in the 12 μm or 16μm wavelength range, are presented. Several methods of pumping are reviewed and two novel pump schemes are presented. A laser pumped laser device design is given, and operation of this device and associated diagnostic equipment is confirmed by repeating experiments in OCS and NH 3 . The results of OCS laser experiments show that an improvement in pump rate and output per unit length is obtained with the device, using a wedged transverse pumping scheme. A new multi-line laser system in NH 3 pumped by a TEA CO 2 laser is reported. More than forty transitions spanning the wavelength range of 9.2 to 13.8 μm are observed and identified. A strong output at 12.08 μm is one of the closest lines yet found to the required laser isotope separation wavelength. Far infrared emission near 65 μm is observed and is responsible for populating levels which lase in pure ammonia near 12.3 μm. Buffer gas (e.g., N 2 or He) pressures of approximately 40--800 torr cause energy transfer by collision-induced rotationaltransitions from the pumped antisymmetric to the lasing symmetric levels in the nu 2 = 1 band of ammonia. Most of the observed lines are aP(J,K) transitions which originate from the nu 2 /sup s/ band. Measurements of the pressure dependence of the laser output shows that some lines lase at pressures greater than one atmosphere. Transient behavior of the 12.08 μm line is calculated from a simplified analytic model and these calculations are compared to the experimental results

  18. Water pumping and analysis of flow in burrowing zoobenthos - a short overview

    DEFF Research Database (Denmark)

    Riisgård, Hans Ulrik; Larsen, Poul Scheel

    2005-01-01

    with the measuring of water pumping and the analysis of flow generated by burrowing deposit- and filter-feeding zoobenthos in order to determine the type of pump and mechanisms involved, flow rate, pump pressure, and pumping power. The practical use of fluid mechanical principles is examined, and it is stressed......-feeding animals. In stagnant situations the near-bottom water may be depleted of food particles, depending on the population filtration rate and the intensity of the biomixing induced by the filtering activity. But moderate currents and the biomixing can presumably generate enough turbulence to facilitate mixing...... of water layers at the sea bed with the layers above where food particle concentrations are relatively higher. Following a brief summary of types of burrowing benthic animals, common methods for measuring pumping rates are described along with examples. For estimating the required pump pressure, biofluid...

  19. Electromechanical performance analysis of inflated dielectric elastomer membrane for micro pump applications

    Science.gov (United States)

    Saini, Abhishek; Ahmad, Dilshad; Patra, Karali

    2016-04-01

    Dielectric elastomers have received a great deal of attention recently as potential materials for many new types of sensors, actuators and future energy generators. When subjected to high electric field, dielectric elastomer membrane sandwiched between compliant electrodes undergoes large deformation with a fast response speed. Moreover, dielectric elastomers have high specific energy density, toughness, flexibility and shape processability. Therefore, dielectric elastomer membranes have gained importance to be applied as micro pumps for microfluidics and biomedical applications. This work intends to extend the electromechanical performance analysis of inflated dielectric elastomer membranes to be applied as micro pumps. Mechanical burst test and cyclic tests were performed to investigate the mechanical breakdown and hysteresis loss of the dielectric membrane, respectively. Varying high electric field was applied on the inflated membrane under different static pressure to determine the electromechanical behavior and nonplanar actuation of the membrane. These tests were repeated for membranes with different pre-stretch values. Results show that pre-stretching improves the electromechanical performance of the inflated membrane. The present work will help to select suitable parameters for designing micro pumps using dielectric elastomer membrane. However this material lacks durability in operation.This issue also needs to be investigated further for realizing practical micro pumps.

  20. Pre study. Prototype of CO2 heat pump system for heating and cooling of a larger building

    International Nuclear Information System (INIS)

    Stene, Joern; Jakobsen, Arne

    2006-03-01

    The activities concerning CO 2 heat pumps during NTNU-SINTEF's strategic research program SMARTBYGG (2002-2006) has lead to an increased interest in planning, building, installing and testing a prototype CO 2 heat pump for heating and cooling of a larger building. In cooperation with Statsbygg and Naeringslivets Idefond a p restudy was initiated in 2005, with the main aim to carry out a set of defined activities, preparing the ground for the realization of a prototype. The following subjects are treated in the p restudy: a technological assessment of the CO 2 heat pumps, a technological assessment of the interaction between the CO 2 heat pump and the secondary systems, a study of the possibilities regarding suitable CO 2 components including compressors, heat exchangers, valves etc., and a presentation of Teknotherm AS (Halden), a Norwegian industrial partner that can project, build and maintain a CO 2 heat pump prototype. During the project period Statsbygg has not found a suitable building where a prototype can be installed. It is recommended that further work is made on the realization of a CO 2 prototype plant by setting up a main project (ml)

  1. CONTAINER DISTRIBUTION AND SLOW RELEASE FERTILIZERS APPLICATION ALONG THE PRE-NURSERY INFLUENCING OIL PALM SEEDLINGS GROWTH

    Directory of Open Access Journals (Sweden)

    Paulo César Teixeira

    2009-09-01

    Full Text Available This research had as objective to verify the influence in growth, nutrition and dry matter partition in oil palm seedling by type and dosages of slow release fertilizers (SRF and percentage of tray occupation by plastic containers during pre-nursery. The experiment consisted of 16 treatments, in factorial scheme: two types of SRF (Osmocote® e Basacote mini, two dosages (0 and 3 kg/m3 and four schemes for the container distribution used to attain 100%, 66%, 50% and 25% of tray occupation. An additional treatment composed of 15 x 15 cm plastic bags filled with soil was added. Pre-germinated seeds of oil palm were put in plastic containers of 120 cm3 containing substratum and in plastic bags containing soil. After three months, the seedlings were transplanted to 40 x 40 cm plastic bags containing soil. At this time, height, diameter, dry matter and concentration of N, P, K, Ca and Mg were evaluated. After 10 months, seedlings were evaluated for height and diameter and after 16 months, seedlings had the height, diameter and dry matter weight evaluated. Addition of SRF was fundamental for seedlings development. Different percentages of tray occupation by containers during pre-nursery did not influence height and diameter of oil palm seedlings at 10 and 16 months old. The evaluation after 10 months showed that plants fertilized with Osmocote® were higher than those fertilized with Basacote mini. The evaluations after 16 months showed that plants fertilized during the pre-nursery had higher height, diameter and leaflets, leaf, aboveground and total dry matter than plants not fertilized.

  2. Heat pump dryers theory, design and industrial applications

    CERN Document Server

    Alves-Filho, Odilio

    2015-01-01

    Explore the Social, Technological, and Economic Impact of Heat Pump Drying Heat pump drying is a green technology that aligns with current energy, quality, and environmental concerns, and when compared to conventional drying, delivers similar quality at a lower cost. Heat Pump Dryers: Theory, Design and Industrial Applications details the progression of heat pump drying-from pioneering research and demonstration work to an applied technology-and establishes principles and theories that can aid in the successful design and application of heat pump dryers. Based on the author's personal experience, this book compares heat pump dryers and conventional dryers in terms of performance, quality, removal rate, energy utilization, and the environmental effect of both drying processes. It includes detailed descriptions and layouts of heat pump dryers, outlines the principles of operation, and explains the equations, diagrams, and procedures used to form the basis for heat pump dryer dimensioning and design. The author ...

  3. Pumping mechanisms in sputter-ion pumps low pressure operation

    International Nuclear Information System (INIS)

    Welch, K.M.

    1991-01-01

    It is shown that significant H 2 pumping occurs in the walls of triode pumps. Also, H 2 is pumped in the anode cells of sputter-ion pumps. This pumping occurs in a manner similar to that by which the inert gases are pumped. That is, H 2 is pumped in the walls of the anode cells by high energy neutral burial. Hydrogen in the pump walls and anodes limits the base pressure of the pump

  4. Tests of a photovoltaic pump: first results

    International Nuclear Information System (INIS)

    Petroselli, A.; Pica, M.; Biondi, P.

    2005-01-01

    The paper deals with a first series of tests conducted in Viterbo (42 deg 25 min North, 12 deg 06 min East) on a PV-DC pump. This series lasted eight months - from the first days of January to the end of August 2003 - and involved measurements of: air and PV-module temperatures; solar radiations, both on horizontal surface and tilted module surface; voltage and intensity of the DC currents from the panel; pump pressures and flow rates. In total, as much as 3,150 data were collected every day. The analysis of the data allowed to obtain some simple empirical relations expressing daily pumped water volumes, instantaneous flow rates and system efficiencies as a function of both radiations and total dynamic heads [it

  5. Aerosol material release rates from zircaloy-4 at temperatures from 2000 to 22000C

    International Nuclear Information System (INIS)

    Mulpuru, S.R.; Wren, D.J.; Rondeau, R.K.

    1987-01-01

    During some postulated severe accidents involving loss of coolant and loss of emergency coolant injection, the temperatures in a CANDU reactor fuel channel become high enough to cause failure and melting of the Zircaloy fuel cladding. At such high temperatures, vapors of fission products and structural (fuel and cladding) materials will be released into the coolant steam and hydrogen mixture. These vapors will condense as cooler conditions are encountered downstream. The vapors from structural materials are relatively involatile; therefore, they will condense readily into aerosol particles. These particles, in turn, will provide sites for the condensation of the more volatile fission products. The aerosol transport of fission products in the primary heat transport system (PHTS) will thus be influenced by the structural material release rates. As part of an ongoing program to develop predictive tools for aerosol and associated fission product transport through the PHTS, experiments have been conducted to measure the vapor mass release rates of the alloying elements from Zircaloy-4 at high temperatures. The paper presents the results and analysis of these experiments

  6. An electrochemical pumping system for on-chip gradient generation.

    Science.gov (United States)

    Xie, Jun; Miao, Yunan; Shih, Jason; He, Qing; Liu, Jun; Tai, Yu-Chong; Lee, Terry D

    2004-07-01

    Within the context of microfluidic systems, it has been difficult to devise pumping systems that can deliver adequate flow rates at high pressure for applications such as HPLC. An on-chip electrochemical pumping system based on electrolysis that offers certain advantages over designs that utilize electroosmotic driven flow has been fabricated and tested. The pump was fabricated on both silicon and glass substrates using photolithography. The electrolysis electrodes were formed from either platinum or gold, and SU8, an epoxy-based photoresist, was used to form the pump chambers. A glass cover plate and a poly(dimethylsiloxane) (PDMS) gasket were used to seal the chambers. Filling of the chambers was accomplished by using a syringe to inject liquid via filling ports, which were later sealed using a glass cover plate. The current supplied to the electrodes controlled the rate of gas formation and, thus, the resulting fluid flow rate. At low backpressures, flow rates >1 microL/min have been demonstrated using polymer electrospray nozzle, we have confirmed the successful generation of a solvent gradient via a mass spectrometer.

  7. Evaluation of reciprocating electromagnetic air pumping for portable PEMFC

    International Nuclear Information System (INIS)

    Kwon, Kilsung; Kang, Ho; Kang, Seongwon; Kim, Daejoong

    2013-01-01

    In this paper, we present a proton exchange membrane fuel cell (PEMFC) integrated with an electromagnetic (EM) air pump. The EM air pump provides the PEMFC with air by reciprocating motions of the permanent magnet attached to a flexible membrane. We performed a parametric study to decide the optimal dimensions of the reciprocating EM air pump. The effects of various operating parameters on the EM air pump were investigated with the root-mean-square (RMS) flow rate and current. A core with a higher relative permeability shows better performance. The RMS current linearly increases with the applied voltage and shows no dependence on the frequency. The RMS flow rate also increases with the voltage. The RMS flow rate per power consumption is highest at the frequency around 20 Hz and decreases as the applied voltage increases. When the reciprocating EM air pump was used to supply air to the portable PEMFC, it was found that the power density of the PEMFC increases with the applied voltage and shows the highest performance at the frequency of 10 Hz. We compared the performance of the PEMFC between the flow meter and the EM air pump used as an air supplier. About 81% of the output power using the flow meter was obtained when the EM air pump is operated at the applied voltage of 5 V. The parasitic power ratio reaches at its minimum value about 0.1 with an EM applied voltage of 0.25V. (paper)

  8. Lung volume and expiratory flow rates from pre- to post-puberty.

    Science.gov (United States)

    Smith, Joshua R; Emerson, Sam R; Kurti, Stephanie P; Gandhi, Kirti; Harms, Craig A

    2015-08-01

    The purpose was to determine if the airways and lungs grow disproportionately from pre- to post-puberty in boys and girls. We hypothesized that the airways grow at a slower rate than lung volume (i.e. dysanapsis growth) during puberty and boys would exhibit more dysanaptic growth compared to girls. Twenty-one pre-pubescent children [11 boys (pre 10.1 ± 0.5 years, post 15.3 ± 0.5 years); 10 girls (pre 9.4 ± 1.0 years, post 14.1 ± 1.0 years)] performed pulmonary function tests (PFTs) ~5 years ago from an original cohort of 40 children. These 21 children performed PFTs, which included forced vital capacity (FVC) and forced expiratory flow at 50 % FVC (FEF50). Static pressure at 50 % of FVC [Pst(L)50 %] was estimated based on age. Dysanapsis ratio (DR) was calculated [FEF50 × FVC(-1) × Pst(L) 50 % (-1) ]. Maturation status was determined via Tanner stages. Stage of maturation was not different (p > 0.05) between boys and girls (4.2 ± 0.6 stage vs. 3.7 ± 0.7 stage, respectively). FVC and FEF50 increased (p 0.05) from pre- to post-puberty. FEF50 and FVC significantly increased and DR decreased (p puberty for both sexes. Post-puberty, boys had a significantly larger FVC, but FEF50, DR, and FEF50/FVC were not different (p > 0.05) compared to girls. These data suggest that dysanaptic growth occurs during puberty and that it is not different between boys and girls.

  9. Pumping mechanisms in sputter-ion pumps low pressure operation

    International Nuclear Information System (INIS)

    Welch, K.M.

    1991-01-01

    It is shown that significant H 2 pumping occurs in the walls of triode pumps. Also, H 2 is pumped in the anode cells of sputter-ion pumps. This pumping occurs in a manner similar to that by which the inert gases are pumped. That is, H 2 pumped in the walls of the anode cells by high energy neutral burial. Hydrogen in the pump walls and anodes limits the base pressure of the pump. 13 refs., 5 figs., 1 tab

  10. Short-term Outcomes following Concussion in the NFL: An 11-year Retrospective Study of Player Release Rate and Financial Loss

    Science.gov (United States)

    Ramkumar, Prem; Navarro, Sergio Michael

    2017-01-01

    Objectives: The primary goal of this study was to assess the short-term outcomes among National Football League (NFL) players following concussion in terms of: (1) DNP protocol activation, (2) release rate at one and three years, and (3) mean salary reduction. A secondary goal of the study was to stratify the post-concussive release rate by franchise and player position. Methods: NFL player transaction records and publicly available weekly injury reports from August 2005 to January 2016 for NFL players were analyzed. All players immediately sustaining recorded concussions were evaluated for a change to inactive or do-not-play (DNP) status. The one-year and three-year release rate following concussion was defined as any player transitioning to inactivation, retirement, free agency, or any failure to return for a successive season on the same team’s active roster after one or three years from the initial concussion. Student’s t-test was used to compare release rates between non-concussed and concussed players at one and three years. Mean salary reduction per year following concussion was calculated using publicly available player contracts. Additionally, franchise-level and position-based analyses of the release rate were performed. Results: Of the total 5,451 NFL players retrospectively analyzed over the 11-year period, 373 sustained publicly reported concussions resulting in DNP protocol activation. The release rate of the post-concussive versus non-concussive player was 26% vs. 20% at 1 year (pfranchise to release an athlete following concussion within one and three years. Table 1 reports a position-based analysis in terms of concussion rate, mean salary reduction, and NFL career longevity. Conclusion: Our retrospective study demonstrates that NFL concussions resulting in DNP protocol activation leads to a statistically greater release rate among concussed NFL players than non-concussed players. Released players suffered reduction in year-over-year accumulated

  11. Pre-irradiation at a low dose-rate blunted p53 response

    International Nuclear Information System (INIS)

    Takahashi, Akihisa

    2002-01-01

    We investigated whether chronic irradiation at a low dose-rate interferes with the p53-centered signal transduction pathyway induced by radiation in human cultured cells and C57BL/6N mice. In in vitro experiments, we found that a challenge with X-ray irradiation immediately after chronic irradiation resulted in lower levels of p53 than those observed after the challenge alone in glioblastoma cells (A-172). In addition, the levels of p53-centered apoptosis and its related proteins after the challenge were strongly correlated with the above-mentioned phenomena in squamous cell carcinoma cells (SAS/neo). In in vivo experiments, the accumulation of p53 and Bax, and the induction of apoptosis were observed dose-dependently in mouse spleen at 12 h after a challenge with X-rays (3.0 Gy). However, we found significant suppression of p53 and Bax accumulation and the induction of apoptosis 12 h after challenge irradiation at 3.0 Gy with a high doses-rate following chronic pre-irradiation (1.5 Gy, 0.001 Gy/min). These findings suggest that chronic pre-irradiation suppressed the p53 function through radiation-induced signaling and/or p53 stability. (author)

  12. Parametric sensitivity study for solar-assisted heat-pump systems

    Science.gov (United States)

    White, N. M.; Morehouse, J. H.

    1981-07-01

    The engineering and economic parameters affecting life-cycle costs for solar-assisted heat pump systems are investigted. The change in energy usage resulting from each engineering parameter varied was developed from computer simulations, and is compared with results from a stand-alone heat pump system. Three geographical locations are considered: Washington, DC, Fort Worth, TX, and Madison, WI. Results indicate that most engineering changes to the systems studied do not provide significant energy savings. The most promising parameters to ary are the solar collector parameters tau (-) and U/sub L/ the heat pump capacity at design point, and the minimum utilizable evaporator temperature. Costs associated with each change are estimated, and life-cycle costs computed for both engineering parameters and economic variations in interest rate, discount rate, tax credits, fuel unit costs and fuel inflation rates. Results indicate that none of the feasibile engineering changes for the system configuration studied will make these systems economically competitive with the stand-alone heat pump without a considerable tax credit.

  13. New approach to exploit optimally the PV array output energy by maximizing the discharge rate of a directly-coupled photovoltaic water pumping system (DC/PVPS)

    International Nuclear Information System (INIS)

    Boutelhig, Azzedine; Hadj Arab, Amar; Hanini, Salah

    2016-01-01

    Highlights: • Mismatches on a designed d-c PV pumping system have been highlighted. • A new approach predicting the maximal discharge has been developed. • The approach has been discussed versus its linearity coefficient. • The approach effectiveness has been investigated and approved. • Theoretical and experimental obtained values have been compared and approved. - Abstract: A directly-coupled photovoltaic water pumping system (DC/PVPS) is generally designed by considering the worst month conditions on lowest daylight-hours, the maximum monthly daily required water volume and tank to store the excess water. In case of absence of hydraulic storage (water tank) or it is not enough dimensioned, the extra amount of pumped water is lost or is not reasonably used, when the system is operated on full daylight-hour. Beside that the extra amount of energy, which might be produced by the PV generator, is not exploited, when the system is operated only during a specified period-time needed to satisfy the demand. Beyond the accurate design that satisfying the end-user, a new approach has been developed as target to exploit maximally the PV array energy production, by maximizing the discharge rate of the system. The methodology consists of approaching maximally the demanded energy to the supplied energy on full operating day. Based on the demand/supply energy condition, the approach has been developed, upon the PV array and the pump performance models. The issued approach predicts the maximum delivery capacity of the system on monthly daily water volumes versus the monthly daily averages of solar irradiation, previously recorded. Its efficacy has been investigated and discussed according to the estimated and experimental values of its linearity coefficient, following the characterization tests of a designed system, carried out at our pumping test facility in Ghardaia (Algeria). The new theoretically and experimentally obtained flow-rates fit well, except

  14. CFD research on runaway transient of pumped storage power station caused by pumping power failure

    International Nuclear Information System (INIS)

    Zhang, L G; Zhou, D Q

    2013-01-01

    To study runaway transient of pumped storage power station caused by pumping power failure, three dimensional unsteady numerical simulations were executed on geometrical model of the whole flow system. Through numerical calculation, the changeable flow configuration and variation law of some parameters such as unit rotate speed,flow rate and static pressure of measurement points were obtained and compared with experimental data. Numerical results show that runaway speed agrees well with experimental date and its error was 3.7%. The unit undergoes pump condition, brake condition, turbine condition and runaway condition with flow characteristic changing violently. In runaway condition, static pressure in passage pulses very strongly which frequency is related to runaway speed

  15. A High-Energy Good-Beam-Quality Krypton-Lamp-Pumped Nd:YAG Solid-State Laser with One Pump Cavity

    Institute of Scientific and Technical Information of China (English)

    LIU Xue-Sheng; WANG Zhi-Yong; YAN Xin; CAO Ying-Hua

    2008-01-01

    We investigate a high-energy good-beam-quality krypton-lamp-pumped pulsed Nd:YAG solid-state laser with one pump cavity.The symmetrical resonator laser is developed and is rated at 80 J with beam parameter product 12mm mrad.The total system electro-optics efficiency of the lamp-pumped YAG laser is as high as 3.3% and the stability of output energy is ±2% with pulse width tunable between 0.1 ms and 10ms.The experimental results are consistent with the theoretical analysis and simulation.

  16. Full-Scale Validation of a Comprehensive Criterion to Predict Fish-Friendliness of Pumps

    NARCIS (Netherlands)

    Krakers, L.A.; Kruyt, Nicolaas P.; Rutjes, H.A.

    2015-01-01

    Many pumping stations in drainage & irrigation applications are currently equipped with conventional (not fish friendly designed) pumps. Field tests have been performed [1] for several pump types of a certain size at certain pumping conditions to assess survival rates of fish passing through pumps.

  17. Groundwater-pumping optimization for land-subsidence control in Beijing plain, China

    Science.gov (United States)

    Qin, Huanhuan; Andrews, Charles B.; Tian, Fang; Cao, Guoliang; Luo, Yong; Liu, Jiurong; Zheng, Chunmiao

    2018-01-01

    Beijing, in the North China plain, is one of the few megacities that uses groundwater as its main source of water supply. Groundwater accounts for about two-thirds of the city's water supply, and during the past 50 years the storage depletion from the unconsolidated aquifers underlying the city has been >10.4 billion m3. By 2010, groundwater pumping in the city had resulted in a cumulative subsidence of greater than 100 mm in an area of about 3,900 km2, with a maximum cumulative subsidence of >1,200 mm. This subsidence has caused significant social and economic losses in Beijing, including significant damage to underground utilities. This study was undertaken to evaluate various future pumping scenarios to assist in selecting an optimal pumping scenario to minimize overall subsidence, meet the requirements of the Beijing Land Subsidence Prevention Plan (BLSPP 2013-2020), and be consistent with continued sustainable economic development. A numerical groundwater and land-subsidence model was developed for the aquifer system of the Beijing plain to evaluate land subsidence rates under the possible future pumping scenarios. The optimal pumping scenario consistent with the evaluation constraints is a reduction in groundwater pumping from three major pumping centers by 100, 50 and 20%, respectively, while maintaining an annual pumping rate of 1.9 billion m3. This scenario's land-subsidence rates satisfy the BLSPP 2013-2020 and the pumping scenario is consistent with continued economic development. It is recommended that this pumping scenario be adopted for future land-subsidence management in Beijing.

  18. Groundwater-pumping optimization for land-subsidence control in Beijing plain, China

    Science.gov (United States)

    Qin, Huanhuan; Andrews, Charles B.; Tian, Fang; Cao, Guoliang; Luo, Yong; Liu, Jiurong; Zheng, Chunmiao

    2018-06-01

    Beijing, in the North China plain, is one of the few megacities that uses groundwater as its main source of water supply. Groundwater accounts for about two-thirds of the city's water supply, and during the past 50 years the storage depletion from the unconsolidated aquifers underlying the city has been >10.4 billion m3. By 2010, groundwater pumping in the city had resulted in a cumulative subsidence of greater than 100 mm in an area of about 3,900 km2, with a maximum cumulative subsidence of >1,200 mm. This subsidence has caused significant social and economic losses in Beijing, including significant damage to underground utilities. This study was undertaken to evaluate various future pumping scenarios to assist in selecting an optimal pumping scenario to minimize overall subsidence, meet the requirements of the Beijing Land Subsidence Prevention Plan (BLSPP 2013-2020), and be consistent with continued sustainable economic development. A numerical groundwater and land-subsidence model was developed for the aquifer system of the Beijing plain to evaluate land subsidence rates under the possible future pumping scenarios. The optimal pumping scenario consistent with the evaluation constraints is a reduction in groundwater pumping from three major pumping centers by 100, 50 and 20%, respectively, while maintaining an annual pumping rate of 1.9 billion m3. This scenario's land-subsidence rates satisfy the BLSPP 2013-2020 and the pumping scenario is consistent with continued economic development. It is recommended that this pumping scenario be adopted for future land-subsidence management in Beijing.

  19. Effect of Pumping on Groundwater Levels: A Case Study

    Science.gov (United States)

    Sindhu, G.; Vijayachandran, Lekshmi

    2018-06-01

    Groundwater is a major source for drinking and domestic purposes. Nowadays, extensive pumping has become a major issue of concern since pumping has led to rapid decline in the groundwater table, thus imposing landward gradient, leading to saline water intrusion especially in coastal areas. Groundwater pumping has seen its utmost effect on coastal aquifer systems, where the sea-ward gradient gets disturbed due to anthropogenic influences. Hence, a groundwater flow modelling of an aquifer system is essential for understanding the various hydro-geologic conditions, which can be used to study the responses of the aquifer system with regard to various pumping scenarios. Besides, a model helps to predict the water levels for the future period with respect to changing environment. In this study, a finite element groundwater flow model of a coastal aquifer system at Aakulam, Trivandrum district is developed, calibrated and simulated using the software Finite Element subsurface Flow system (FEFLOW 6.2).This simulated model is then used to predict the groundwater levels for a future 5 year period during pre monsoon and post monsoon season.

  20. Effect of Pumping on Groundwater Levels: A Case Study

    Science.gov (United States)

    Sindhu, G.; Vijayachandran, Lekshmi

    2018-03-01

    Groundwater is a major source for drinking and domestic purposes. Nowadays, extensive pumping has become a major issue of concern since pumping has led to rapid decline in the groundwater table, thus imposing landward gradient, leading to saline water intrusion especially in coastal areas. Groundwater pumping has seen its utmost effect on coastal aquifer systems, where the sea-ward gradient gets disturbed due to anthropogenic influences. Hence, a groundwater flow modelling of an aquifer system is essential for understanding the various hydro-geologic conditions, which can be used to study the responses of the aquifer system with regard to various pumping scenarios. Besides, a model helps to predict the water levels for the future period with respect to changing environment. In this study, a finite element groundwater flow model of a coastal aquifer system at Aakulam, Trivandrum district is developed, calibrated and simulated using the software Finite Element subsurface Flow system (FEFLOW 6.2).This simulated model is then used to predict the groundwater levels for a future 5 year period during pre monsoon and post monsoon season.

  1. Design and experimental characterization of an EM pump

    International Nuclear Information System (INIS)

    Kim, Hee Reyoung; Hong, Sang Hee

    1999-01-01

    Generally, an EM (electromagnetic) pump is been employed to circulate electrically conducting liquids by using the Lorentz force. Especially, at the liquid metal reactor (LMR), which uses liquid sodium with high electrical conductivity as a coolant, an EM pump is needed due to its advantages over a mechanical pump, such as no rotating parts, no noise, and simplicity. In this research, an EM pump of a pilot annular linear induction type with a flow rate of 200 l/min was designed by using the electrical equivalent-circuit method. The pump was designed and manufactured by considering material and environmental (high temperature and liquid sodium) requirements. The pump performance was experimentally characterized based on input currents, voltage, power, and frequency. Also, the theoretical prediction was compared with the experimental result

  2. Optimization of end-pumped, actively Q-switched quasi-III-level lasers.

    Science.gov (United States)

    Jabczynski, Jan K; Gorajek, Lukasz; Kwiatkowski, Jacek; Kaskow, Mateusz; Zendzian, Waldemar

    2011-08-15

    The new model of end-pumped quasi-III-level laser considering transient pumping processes, ground-state-depletion and up-conversion effects was developed. The model consists of two parts: pumping stage and Q-switched part, which can be separated in a case of active Q-switching regime. For pumping stage the semi-analytical model was developed, enabling the calculations for final occupation of upper laser level for given pump power and duration, spatial profile of pump beam, length and dopant level of gain medium. For quasi-stationary inversion, the optimization procedure of Q-switching regime based on Lagrange multiplier technique was developed. The new approach for optimization of CW regime of quasi-three-level lasers was developed to optimize the Q-switched lasers operating with high repetition rates. Both methods of optimizations enable calculation of optimal absorbance of gain medium and output losses for given pump rate. © 2011 Optical Society of America

  3. Epizoic zoanthids reduce pumping in two Caribbean vase sponges

    Science.gov (United States)

    Lewis, T. B.; Finelli, C. M.

    2015-03-01

    Sponges are common sessile benthic suspension feeders that play a critical role in carbon and nitrogen cycling within reef ecosystems via their filtration capabilities. Due to the contribution of sponges in benthic-pelagic coupling, it is critical to assess factors that may affect their role in the healthy function of coral reefs. Several factors can influence the rate at which an individual sponge pumps water, including body size, environmental conditions, mechanical blockage, and reduction of inhalant pores (ostia). Symbiotic zoanthid colonization is a common occurrence on Caribbean sponges, and the presence of zoanthids on the surface of a sponge may occlude or displace the inhalant ostia. We quantified pumping rates of the giant barrel sponge, Xestospongia muta ( N = 22 uncolonized, 37 colonized) and the common vase sponge, Niphates digitalis ( N = 21 uncolonized, 17 colonized), with and without zoanthid symbionts, Parazoanthus catenularis and Parazoanthus parasiticus, respectively. For X. muta, biovolume-normalized pumping rates of individuals colonized by zoanthids were approximately 75 % lower than those of uncolonized sponges. Moreover, colonization with zoanthids was related to a difference in morphology relative to uncolonized individuals: Colonized sponges exhibited an osculum area to biovolume ratio that was nearly 65 % less than uncolonized sponges. In contrast, the presence of zoanthids on N. digitalis resulted in only a marginal decrease in pumping rates and no detectable difference in morphology. The difference in zoanthid effects between X. muta and N. digitalis is likely due to the differences in wall thickness and architecture between the two species. The probable cause of reduced pumping in affected sponges is occupation of the sponge surface that leads to blockage or displacement of inhalant ostia. To partially test this hypothesis, zoanthid colonization on specimens of X. muta was simulated by wrapping sponges with plastic mesh of varying

  4. Parametric representation of centrifugal pump homologous curves

    International Nuclear Information System (INIS)

    Veloso, Marcelo A.; Mattos, Joao R.L. de

    2015-01-01

    Essential for any mathematical model designed to simulate flow transient events caused by pump operations is the pump performance data. The performance of a centrifugal pump is characterized by four basic quantities: the rotational speed, the volumetric flow rate, the dynamic head, and the hydraulic torque. The curves showing the relationships between these four variables are called the pump characteristic curves. The characteristic curves are empirically developed by the pump manufacturer and uniquely describe head and torque as functions of volumetric flow rate and rotation speed. Because of comprising a large amount of points, this configuration is not suitable for computational purposes. However, it can be converted to a simpler form by the development of the homologous curves, in which dynamic head and hydraulic torque ratios are expressed as functions of volumetric flow and rotation speed ratios. The numerical use of the complete set of homologous curves requires specification of sixteen partial curves, being eight for the dynamic head and eight for the hydraulic torque. As a consequence, the handling of homologous curves is still somewhat complicated. In solving flow transient problems that require the pump characteristic data for all the operation zones, the parametric form appears as the simplest way to deal with the homologous curves. In this approach, the complete characteristics of a pump can be described by only two closed curves, one for the dynamic head and other for the hydraulic torque, both in function of a single angular coordinate defined adequately in terms of the quotient between volumetric flow ratio and rotation speed ratio. The usefulness and advantages of this alternative method are demonstrated through a practical example in which the homologous curves for a pump of the type used in the main coolant loops of a pressurized water reactor (PWR) are transformed to the parametric form. (author)

  5. Isopleths of surface concentration and surface exposure rate due to a radioactive cloud released from a stack

    International Nuclear Information System (INIS)

    Kobayashi, Hideo; Yabuta, Hajimu; Katagiri, Hiroshi; Obata, Kazuichi; Kokubu, Morinobu

    1982-03-01

    Various calculations are made to estimate the distributions of concentration and γ-exposure rate due to a radioactive cloud released from a point source to the atmosphere. In this report, the isopleths of concentration and γ-exposure rate which were calculated are given in graphs to enable rapid prediction of the influence of released radioactive material in the emergency situation. Recently there are facilities which are equipped with a system to display the calculation results on CRT; but such practice is rather rare. By placing the calculated isopleths of reduction scale 1/25000 or 1/50000 on the usual map, any facilities without the CRT system can readily estimate the influence of an accidental release. The graphs of isopleths are given with the release height (11 values of 0 to 200 m at about 20 m intervals) and the atmospheric stability (6 classes) as parameters. Calculations of γ-exposure rates were made using the computer code GAMPUL developed by T. Hayashi and T. Shiraishi. In the calculation of radioactive concentrations and γ-exposure rates, the vertical diffusion depths, σsub(z), exceeding 1000 m are taken to be 1000 m according to the Meteorological Guide for the Safety Analysis of Power Reactor (J.AEC). The comparison between with and without this limitation in σsub(z) is made in the case of downwind axial surface distributions. (author)

  6. Airborne release fractions/rates and respirable fractions for nonreactor nuclear facilities. Volume 2, Appendices

    International Nuclear Information System (INIS)

    1994-12-01

    This document contains compiled data from the DOE Handbook on Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear facilities. Source data and example facilities utilized, such as the Plutonium Recovery Facility, are included

  7. MK-III function tests in JOYO. Primary main cooling pump

    International Nuclear Information System (INIS)

    Isozaki, Kazunori; Saito, Takakazu; Sumino, Kouzo; Karube, Kouji; Terano, Toshihiro; Sakaba, Hideo; Nakai, Satoru

    2004-06-01

    MK-III function test (SKS-1) that was carried out from October 17, 2001 through October 23, 2001 using MK-III transition core configuration and MK-III function tests (SKS-2) was carried out from January 27, 2003 through February 13, 2003 using MK-III core configuration. The major function tests results of primary cooling system were shown as follows; (1) The stability of the primary main pump flow control system was confirmed on both CAS (cascade) mode and Man (manual) mode. Also no divergence of flow and revolution of the pump were observed at step flow change disturbance. (2) The main motor was shifted to run-back flow control operation in about 54 seconds after scram. The flow rate and pump revolution at run-back operation of A and B cooling system were 167 m 3 /h and 117 rpm, 185m 3 /h and 118 rpm respectively. The pump revolution was within the design target revolution 122 rpm ± 8 rpm and the flow was over the 10% of the rated flow. (3) The pony motor was engaged in operation in about 39 seconds after the primary main pump trip. The flow rate and pump revolution at the pony motor operation of A and B cooling system were 180 m 3 /h and 124 rpm, 190 m 3 /h and 123 rpm respectively. These values were satisfied the design low limit of 93 rpm and 10% of the rated flow. (4) Free flow coast down time constant was longer than 10 seconds that was design shortest time at both the primary pump trip and run-back operation. (5) Pump over flow column sodium levels of both A and B cooling system at rated operating condition were NL-1550 mm and, NL-1468 mm respectively and were lower than NL-1581 mm of the design value. This result shows the new IHX pressure loss estimation was conservative. (6) It was confirmed that the primary main pump could operate with out scram for up to 0.6 seconds of external power supply loss. (author)

  8. Vacuum pump age effects by the exposure to the corrosive gases on the Cr etch rate as observed using optical emission spectroscopy in an Ar/O{sub 2}/Cl{sub 2} mixed plasma

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seolhye; Roh, Hyun-Joon; Jang, Yunchang; Jeong, Sangmin; Ryu, Sangwon; Choe, Jae-Myung; Kim, Gon-Ho, E-mail: ghkim@snu.ac.kr

    2016-03-31

    Vacuum pumps of different ages were used to prepare Cl{sub 2} based plasmas for use in Cr etching. The effects of the vacuum pump age on the etching results were investigated using optical emission spectroscopy analysis. The composition of gas at the base pressure was mainly nitrogen and oxygen, although the ratio depended on the vacuum pump age and therefore, modulated the etch rate in a manner that was difficult to monitor. The effects of the pump age on the etch rate were clearly observed in the Cl{sub 2} plasma-assisted chromium film etching process, in which oxygen and chlorine radicals were responsible for the etching process. The electron energy distribution function (EEDF), which provided a proxy for the thermal equilibrium properties of the etching plasmas, was monitored. The shape of EEDF was derived from an analysis of the optical emission spectral data using an analysis model described previously. Because molecular nitrogen has a higher threshold energy and a larger cross-section of inelastic collisional processes than oxygen, the tail of the EEDF depends on the mixing ratio between nitrogen and oxygen. The various mechanisms that contribute to the chromium etch rate varied with subtle differences in the vacuum conditions, which were determined by age of the turbo molecular pump. The rates at which oxygen and chlorine radicals were generated were estimated using the measured EEDF, and the estimated oxygen radical and etching product contents were verified by comparing the residual gas analyzer data. The results revealed that the residual nitrogen partial pressures in two etchers equipped with either a new or an aged pump differed by 0.18%, and the EEDF tail areas differed by 10{sup −4}. Importantly, the chromium etch rates in these two instruments differed by 30%. These results suggest that the chamber-to-chamber mismatch should be monitored during plasma-assisted device fabrication processes. - Highlights: • We observed the vacuum pump age effect

  9. Double-effect absorption heat pump, phase 3

    Science.gov (United States)

    Cook, F. B.; Cremean, S. P.; Jatana, S. C.; Johnson, R. A.; Malcosky, N. D.

    1987-06-01

    The RD&D program has resulted in design, development and testing of a packaged prototype double-effect generator cycle absorption gas heat pump for the residential and small commercial markets. The 3RT heat pump prototype has demonstrated a COPc of 0.82 and a COPh of 1.65 at ARI rating conditions. The heat pump prototype includes a solid state control system with built-in diagnostics. The absorbent/refrigerant solution thermophysical properties were completely characterized. Commercially available materials of construction were identified for all heat pump components. A corrosion inhibitor was identified and tested in both static and dynamic environments. The safety of the heat pump was analyzed by using two analytical approaches. Pioneer Engineering estimated the factory standard cost to produce the 3RT heat pump at $1,700 at a quantity of 50,000 units/year. One United States patent was allowed covering the heat pump technology, and two divisional applications and three Continuation-in-Park Applications were filed with the U.S.P.T.O. Corresponding patent coverage was applied for in Canada, the EEC, Australia, and Japan. Testing of the prototype heat pump is continuing, as are life tests of multiple pump concepts amd long-term dynamic corrosion tests. Continued development and commercialization of gas absorption heat pumps based on the technology are recommended.

  10. A cryocondensation pump for the DIII-D Advanced Divertor Program

    International Nuclear Information System (INIS)

    Smith, J.P.; Baxi, C.; Reis, E.; Sevier, L.

    1992-03-01

    A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m 2 liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the water-cooled vacuum vessel wall. Supports for the pump were designed to accommodate the thermal differences between the 4 K helium surface, the 77 K nitrogen shells, and the 300 K vacuum vessel supporting the pump and to provide a low heat leak structural support. Disruption loading on the pump was analyzed and a finite element structural analysis of the pump was completed. A testing program was completed to evaluate coating techniques to enhance heat transfer and emissivity of the various surfaces. Fabrication tests were performed to determine the best method of attaching the liquid nitrogen flow tubes to their shield surfaces and to determine the best alternative to fabricating the different shells of the pump. A prototype sector of the pump was built to verify fabrication and assembly techniques

  11. Centrifugal pumps

    CERN Document Server

    Anderson, HH

    1981-01-01

    Centrifugal Pumps describes the whole range of the centrifugal pump (mixed flow and axial flow pumps are dealt with more briefly), with emphasis on the development of the boiler feed pump. Organized into 46 chapters, this book discusses the general hydrodynamic principles, performance, dimensions, type number, flow, and efficiency of centrifugal pumps. This text also explains the pumps performance; entry conditions and cavitation; speed and dimensions for a given duty; and losses. Some chapters further describe centrifugal pump mechanical design, installation, monitoring, and maintenance. The

  12. Time Deployment Study for Annulus Pumping

    International Nuclear Information System (INIS)

    REBERGER, D.W.

    2000-01-01

    Radioactive wastes from processing irradiated uranium fuels have been stored as alkaline slurries in underground tanks at the Hanford Site. Single-shell tanks (SST) and double-shell tanks (DST) of various sizes were used for waste storage. Of the total 177 tanks, there are 28 DSTs. DSTs are located in AN, AP, AW, AY, AZ, and SY tank farms in the 200 East (200E) and 200-West (200W) Areas. The storage capacities of the DSTs vary from 980,000 to 1,140,000 gal. DSTs are designed and constructed as an integral steel structure, i.e., an inner shell within an outer shell, so that any leak from the inner shell is confined within the annulus without impacting the environment. The inner shell provides primary containment for the wastes and the outer shell provides secondary containment in the form of an annulus. The annulus of a DST is equipped with a pump pit, leak detection probes, and other accessories. The existing annulus pumps in the DSTs need to be revamped with a new system to reduce operating costs and reduce the time to deploy a pumping system. The new pumping system will minimize the likelihood of a release of waste into the environment; improve capability of waste removal to the maximum extent possible to comply with Washington Administrative Code (WAC) 173-303-640 and Code of Federal Regulations (CFR) 40 CFR 265.193. This study addresses the time required to deploy an annulus pumping system designed to fit any DST after detection of a leak in the inner shell of the DST

  13. Effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, Acipenser ruthenus

    DEFF Research Database (Denmark)

    Siddique, Mohammad Abdul Momin; Butts, Ian; Psěnička, Martin

    2015-01-01

    , while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5. min pre-incubation increased the fertilization rate than 10. min. At 0. min pre......-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1. min fertilization increased at the 4300:1 ratio. At the 10. min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5. min pre-incubation time, the 43,000:1 ratio increased the fertilization rate...... than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for

  14. Potential airborne release from soil-working operations in a contaminated area

    International Nuclear Information System (INIS)

    Sutter, S.L.

    1980-08-01

    Experiments were performed to provide an indication of how much material could be made airborne during soil-working operations in a contaminated area. Approximately 50 kg of contaminated soil were collected, dried, and mixed, and particle size distribution and 137 Cs content were characterized. In four experiments performed in a 2 ft x 2 ft wind tunnel at the Radioactive Aerosol Release Test Facility, soil was pumped into an airstream moving at 3.2, 10.4, 15.2, and 20 mph. These experiments were designed to maximize airborne releases by fluidizing the soil as it was pumped into the wind tunnel. Thus the airborne releases should represent upper limit values for soil-working operations. Airborne concentration and particle size samples were collected and all of the material deposited downstream was collected to calculate a mass balance. The fraction airborne was calculated using these measurements

  15. Electromagnetic pumping of liquid lithium in inertial confinement fusion reactors

    International Nuclear Information System (INIS)

    Baker, R.S.; Blink, J.A.; Tessier, M.J.

    1983-01-01

    The basic operating principles and geometries of ten electromagnetic pumps are described. Two candidate pumps, the annular-linear-induction pump and the helical-rotor electromagnetic pump, are compared for possible use in a full-scale liquid-lithium inertial confinement fusion reactor. A parametric design study completed for the helical-rotor pump is shown to be valid when applied to an experimental sodium pump. Based upon the preliminary HYLIFE requirements for a lithium flow rate per pump of 8.08 m 3 /s at a head of 82.5 kPa, a complete set of 70 variables are specified for a helical-rotor pump with either a normally conducting or a superconducting winding. The two alternative designs are expected to perform with efficiencies of 50 and 60%, respectively

  16. Reactor coolant pump seal leakage monitoring

    International Nuclear Information System (INIS)

    Stevens, D.M.; Spencer, J.W.; Morris, D.J.; James, W.; Shugars, H.G.

    1986-01-01

    Problems with reactor coolant pump seals have historically accounted for a large percentage of unscheduled outages. Studies performed for the Electric Power Research Institute (EPRI) have shown that the replacement of coolant pump seals has been one of the leading causes of nuclear plant unavailability over the last ten years. Failures of coolant pump seals can lead to primary coolant leakage rates of 200-500 gallons per minute into the reactor building. Airborne activity and high surface contamination levels following these failures require a major cleanup effort and increases the time and personnel exposure required to refurbish the pump seals. One of the problems in assessing seal integrity is the inability to accurately measure seal leakage. Because seal leakage flow is normally very small, it cannot be sensed directly with normal flow instrumentation, but must be inferred from several other temperature and flow measurements. In operating plants the leakage rate has been quantified with a tipping-bucket gauge, a device which indicates when one quart of water has been accumulated. The tipping-bucket gauge has been used for most rainfall-intensity monitoring. The need for a more accurate and less expensive gauge has been addressed. They have developed a drop-counter precipitation sensor has been developed and optimized. The applicability of the drop-counter device to the problem of measuring seal leakage is being investigated. If a review of system specification and known drop-counter performance indicates that this method is feasible for measuring seal leak rates, a drop-counter gauge will be fabricated and tested in the laboratory. If laboratory tests are successful the gauge will be demonstrated in a pump test loop at Ontario Hydro and evaluated under simulated plant conditions. 3 references, 2 figures

  17. Increasing the pump-up rate to polarize 3He gas using spin-exchange optical pumping method

    International Nuclear Information System (INIS)

    Lee, W.T.; Tong Xin; Rich, Dennis; Liu Yun; Fleenor, Michael; Ismaili, Akbar; Pierce, Joshua; Hagen, Mark; Dadras, Jonny; Robertson, J. Lee

    2009-01-01

    In recent years, polarized 3 He gas has increasingly been used as neutron polarizers and polarization analyzers. Two of the leading methods to polarize the 3 He gas are the spin-exchange optical pumping (SEOP) method and the meta-stable exchange optical pumping (MEOP) method. At present, the SEOP setup is comparatively compact due to the fact that it does not require the sophisticated compressor system used in the MEOP method. The temperature and the laser power available determine the speed, at which the SEOP method polarizes the 3 He gas. For the quantity of gas typically used in neutron scattering work, this speed is independent of the quantity of the gas required, whereas the polarizing time using the MEOP method is proportional to the quantity of gas required. Currently, using the SEOP method to polarize several bar-liters of 3 He to 70% polarization would require 20-40 h. This is an order of magnitude longer than the MEOP method for the same quantity of gas and polarization. It would therefore be advantageous to speed up the SEOP process. In this article, we analyze the requirements for temperature, laser power, and the type of alkali used in order to shorten the time required to polarize 3 He gas using the SEOP method.

  18. Development of liquid nitrogen Centrifugal Pump

    International Nuclear Information System (INIS)

    Abe, M; Sagiyama, R; Tsuchiya, H; Takayama, T; Torii, Y; Nakamura, M; Hoshino, Y; Odashima, Y

    2009-01-01

    Usually liquid nitrogen (LN 2 ) transfer from a container to a laboratory equipment takes place by applying pressure to the container to push out liquid or pouring liquid into the cryostat directly by lifting the container. In order to overcome inconvenience of pressuring or lifting containers, we have been developing the Liquid Nitrogen Centrifugal Pump of a small electric turbine pump. Significant advantages that both reducing time to fill LN 2 and controlling the flow rate of liquid into the cryostat are obtained by introducing this pump. We have achieved the lift of about 800mm with the vessel's opening diameter of 28mm.

  19. LMFBR with booster pump in pumping loop

    International Nuclear Information System (INIS)

    Rubinstein, H.J.

    1975-01-01

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation

  20. 40 CFR 90.408 - Pre-test procedures.

    Science.gov (United States)

    2010-07-01

    ....408 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... during service accumulation is allowed only in accordance with § 90.118. (b) Engine pre-test preparation... by § 90.324(a). If necessary, allow the heated sample line, filters, and pumps to reach operating...

  1. Pitfalls of Insulin Pump Clocks

    Science.gov (United States)

    Reed, Amy J.

    2014-01-01

    The objective was to raise awareness about the importance of ensuring that insulin pumps internal clocks are set up correctly at all times. This is a very important safety issue because all commercially available insulin pumps are not GPS-enabled (though this is controversial), nor equipped with automatically adjusting internal clocks. Special attention is paid to how basal and bolus dose errors can be introduced by daylight savings time changes, travel across time zones, and am-pm clock errors. Correct setting of insulin pump internal clock is crucial for appropriate insulin delivery. A comprehensive literature review is provided, as are illustrative cases. Incorrect setting can potentially result in incorrect insulin delivery, with potential harmful consequences, if too much or too little insulin is delivered. Daylight saving time changes may not significantly affect basal insulin delivery, given the triviality of the time difference. However, bolus insulin doses can be dramatically affected. Such problems may occur when pump wearers have large variations in their insulin to carb ratio, especially if they forget to change their pump clock in the spring. More worrisome than daylight saving time change is the am-pm clock setting. If this setting is set up incorrectly, both basal rates and bolus doses will be affected. Appropriate insulin delivery through insulin pumps requires correct correlation between dose settings and internal clock time settings. Because insulin pumps are not GPS-enabled or automatically time-adjusting, extra caution should be practiced by patients to ensure correct time settings at all times. Clinicians and diabetes educators should verify the date/time of insulin pumps during patients’ visits, and should remind their patients to always verify these settings. PMID:25355713

  2. A One-Square-Millimeter Compact Hollow Structure for Microfluidic Pumping on an All-Glass Chip

    Directory of Open Access Journals (Sweden)

    Xing Yue (Larry Peng

    2016-04-01

    Full Text Available A micro surface tension pump is a new type of low-cost, built-in, all-glass, microfluidic pump on a glass microchip fabricated by one-step glass etching. However, geometric minimization and optimization for practical use are challenging. Here, we report a one-square-millimeter, built-in, all-glass pump controlled by two-way digital gas pressure. The pump consists simply of two joint chambers and a piston between two gas control channels. It does not require pre-perfusion for initialization, and can immediately begin to run when a liquid enters its inlet channel. It is also more reliable than conventional micro pumps for practical use due to its ability to restart after the formation of a blocking bubble, which can serve as a valuable troubleshooting procedure. Its volumetric pump output was 0.5–0.7 nL·s−1 under a pump head pressure of 300 Pa.

  3. Study of an electromagnetic pump applied to a primary main pump of a large scale sodium cooled reactor

    International Nuclear Information System (INIS)

    Aizawa, Kosuke; Kotake, Shoji; Chikazawa, Yoshitaka; Ara, Kuniaki; Araseki, Hideo; Aizawa, Rie; Ota, Hiroyuki

    2009-01-01

    This paper describes a future innovative design options with a parallel electromagnetic pump (EMP) system as the main circulating pump of the JSFR design. A conceptual design of EMPs integrated with an intermediate heat exchanger (IHX) is carried out. The major design parameters are consistent with the current JSFR design, where the main flow rate is 630 m 3 /min and the flow halving time is the same of the mechanical pump with the similar reliability. As a result of several design studies, a five parallel EMPs with IHX system has been selected from the geometry suitability for JSFR design. The EMP advantages comparing with mechanical pumps are investigated from the views of in-service inspection, maintenance and reliability. Numerical analysis with two dimensional MHD codes is conducted on a former experiment of a 160 m 3 /min flow rate EMP. The overall trend of the experimental data and the numerical results agrees with that in small-scale EMPs. However, the difference between the experimental data and the numerical results seems larger compared with the small-scale EMPs, which comes from large magnetic Reynolds number and interaction parameter of 160 m 3 /min EMP. (author)

  4. An implantable centrifugal blood pump for long term circulatory support.

    Science.gov (United States)

    Yamazaki, K; Litwak, P; Kormos, R L; Mori, T; Tagusari, O; Antaki, J F; Kameneva, M; Watach, M; Gordon, L; Umezu, M; Tomioka, J; Koyanagi, H; Griffith, B P

    1997-01-01

    A compact centrifugal blood pump was developed as an implantable left ventricular assist system. The impeller diameter is 40 mm and the pump dimensions are 55 x 64 mm. This first prototype was fabricated from titanium alloy, resulting in a pump weight of 400 g including a brushless DC motor. Weight of the second prototype pump was reduced to 280 g. The entire blood contacting surface is coated with diamond like carbon to improve blood compatibility. Flow rates of over 7 L/min against 100 mmHg pressure at 2,500 rpm with 9 W total power consumption have been measured. A newly designed mechanical seal with a recirculating purge system ("Cool-Seal") is used as a shaft seal. In this seal system, seal temperature is kept under 40 degrees C to prevent heat denaturation of blood proteins. Purge fluid also cools the pump motor coil and journal bearing. The purge fluid is continuously purified and sterilized by an ultrafiltration filter incorporated into the paracorporeal drive console. In vitro experiments with bovine blood demonstrated an acceptably low hemolysis rate (normalized index of hemolysis = 0.005 +/- 0.002 g/100 L). In vivo experiments are currently ongoing using calves. Via left thoracotomy, left ventricular apex-descending aorta bypass was performed utilizing a PTFE (Polytetrafluoroethylene) vascular graft, with the pump placed in the left thoracic cavity. In two in vivo experiments, pump flow rate was maintained at 5-8 L/min, and pump power consumption remained stable at 9-10 W. All plasma free hemoglobin levels were measured at < 15 mg/dl. The seal system has demonstrated good seal capability with negligible purge fluid consumption (< 0.5 ml/ day). Both animals remain under observation after 162 and 91 days of continuous pump function.

  5. REMOVE AND RELEASE OF NUTRIENTS AFTER HYBRID PRE-TREATMENT OF ACTIVATED SLUDGE FOAM

    Directory of Open Access Journals (Sweden)

    Alicja Machnicka

    2017-02-01

    Full Text Available One of the problems in wastewater treatment technologies is the formation of foam/scum on the surface of bioreactors. The foam elimination/destruction can be carried out by various methods among which disintegration is included. Hybrid disintegration (chemical decomposition and hydrodynamic cavitation of the foam microorganisms results in phosphates, ammonium nitrogen, magnesium and potassium transferred from the foam solids into the liquid phase. Application of both methods as a hybrid pre-treatment process caused in an increased concentration of phosphates of about 677 mg PO43- L-1, ammonium nitrogen about 41 mg N-NH4+ L-1. The concentration of Mg2+ and K+ in the solution increased from 6.2 to 31.1 mg Mg2+ L-1 and from 22.4 to 102.0 mg K+ L-1, respectively. The confirmation of physicochemical changes and release of cellular matter as a result of cellular lysis (hybrid disintegration was IR analysis. It was demonstrated that the disintegration of foam permits removal of a part of nutrients in the form of struvite.

  6. The pumping of hydrogen and helium by sputter-ion pumps

    International Nuclear Information System (INIS)

    Welch, K.M.; Pate, D.J.; Todd, R.J.

    1992-01-01

    The pumping of hydrogen in diode and triode sputter-ion pumps is discussed. The type of cathode material used in these pumps is shown to have a significant impact on the effectiveness with which hydrogen is pumped. Examples of this include data for pumps with aluminum and titanium-alloy cathodes. Diode pumps with aluminum cathodes are shown to be no more effective in the pumping of hydrogen than in the pumping of helium. The use of titanium or titanium alloy anodes is also shown to measurably impact on the speed of these pumps at.very low pressures. This stems from the fact that hydrogen is x10 6 more soluble in titanium than in stainless steel. Hydrogen becomes resident in the anodes because of fast neutral burial. Lastly, quantitative data are given for the He speeds and capacities of both noble and conventional diode and triode pumps. The effectiveness of various pump regeneration procedures, subsequent to the pumping of He, is reported.These included bakeout and N 2 glow discharge cleaning. The comparative desorption of He with the subsequent pumping of N 2 is reported on. The N 2 speed of these pumps was used as the benchmark for defining the size of the pumps vs. their respective He speeds

  7. Laser-diode pumped self-mode-locked praseodymium visible lasers with multi-gigahertz repetition rate.

    Science.gov (United States)

    Zhang, Yuxia; Yu, Haohai; Zhang, Huaijin; Di Lieto, Alberto; Tonelli, Mauro; Wang, Jiyang

    2016-06-15

    We demonstrate efficient laser-diode pumped multi-gigahertz (GHz) self-mode-locked praseodymium (Pr3+) visible lasers with broadband spectra from green to deep red for the first time to our knowledge. With a Pr3+-doped GdLiF4 crystal, stable self-mode-locked visible pulsed lasers at the wavelengths of 522 nm, 607 nm, 639 nm, and 720 nm have been obtained with the repetition rates of 2.8 GHz, 3.1 GHz, 3.1 GHz, and 3.0 GHz, respectively. The maximum output power was 612 mW with the slope efficiency of 46.9% at 639 nm. The mode-locking mechanism was theoretically analyzed. The stable second-harmonic mode-locking with doubled repetition frequency was also realized based on the Fabry-Perot effect formed in the laser cavity. In addition, we find that the polarization directions were turned with lasing wavelengths. This work may provide a new way for generating efficient ultrafast pulses with high- and changeable-repetition rates in the visible range.

  8. Impact of pre-equilibration and diffusion limited release kinetics on effluent concentration in column leaching tests: Insights from numerical simulations.

    Science.gov (United States)

    Finkel, Michael; Grathwohl, Peter

    2017-05-01

    Column leaching tests have become a standard method for assessing leaching of pollutants from materials used, e.g., for road and railway constructions and in landscaping measures. Column tests showed to be practical in laboratories yielding robust and reproducible results. However, considerable uncertainty still exists related particularly to the degree of equilibration of the pore water with the solids during preparation (pre-equilibration) and percolation of the column. We analyse equilibration time scales and sensitivity of concentrations in column leachate with respect to initial conditions in a series of numerical experiments covering a broad spectrum of material and solute properties. Slow release of pollutants from solid materials is described by a spherical diffusion model of kinetic sorption accounting for multiple grain size fractions and sorption capacities. Results show that the cumulative concentrations are rather independent of the pre-equilibration level for a broad spectrum of parameter settings, e.g. if intra-particle porosity is high, grain size is small, or if the sorption coefficient is large. Sensitivity increases with decreasing liquid solid ratios and contact time during percolation. Significant variations with initial column conditions are to be expected for material and compound properties leading to slow release kinetics. In these cases, sensitivity to initial conditions may have to be considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Numerical simulation and analysis of cavitation flows in a double suction centrifugal pump

    International Nuclear Information System (INIS)

    Meng, G; Tan, L; Cao, S L; Jian, W; Liu, W W; Jiang, D J

    2015-01-01

    Cavitation is an unsteady phenomenon, which is nearly inevitable in pumps. It would degrade the pump performance, generate vibrations and noises, and even erode pump flow passage components. The double suction centrifugal pump at design flow rate and large flow rate is numerically simulated using the k-ω turbulence model and the mass transport cavitation model. As a result, the calculated variation of pump head with pump inlet pressure agreed well with the experimental data. The results demonstrate that the numerical model and method can accurately predict the cavitation flows in a double suction centrifugal pump. The cavitation characteristics are analysed in great details. In addition, based on the calculation results, the reason that the plunge of pump head curve is revealed. It is found that the steep fall of pump head happens when the cavity reaches the blade to blade throat and the micro-vortex group appears at the back of the blade suction side. At the same time, this practice can provide guidance for the optimal design of double suction pumps

  10. An experimental study on pump clogging

    International Nuclear Information System (INIS)

    Isono, M; Nohmi, M; Uchida, H; Kawai, M; Kudo, H; Kawahara, T; Miyagawa, K; Saito, S

    2014-01-01

    For sewage pump that various foreign substance is flowed into, anti-clogging performance is a factor as important as pump efficiency in order to avoid clogging trouble by foreign substance. Many investigations about pump inner flow and pump efficiency estimation have been carried out conventionally in order to realize coexistence with anti-clogging performance and pump performance. And these results have been reflected in construction of the running water section design method. As a index of anti-clogging performance, ''impeller passage diameter'' which is diameter of spherical solid that can pass through the pump is used widely. And there are various type of the sewage pump which have large impeller passage diameter. However real cause of clog is not a solid, and it is fibrous material such as towel and clothes, vinyl and paper diaper. In most case these material accumulate in the pump, so that clog is occurred. In this study, for the purpose of quantification of anti-clogging performance against fibrous materials, the factor that affect to clogging of pump was investigated by pump model test using a string. The test is done based on Taguchi method. In this test, type of the pump model, diameter of the string, material of the string, length of the string and flow rate are selected for the factor, and the effect that they have on the clogging of the pump was investigated. As a result of this test, it was made clear that length of the string has a strong influence on the clogging of the pump. And from the result of this test, evaluation method of anti-clogging performance of the pump against fibrous material by using string was considered. According to the result of above test based on Taguchi method, it was assumed that quantification of anti-clogging performance against fibrous materials is possible by flowing plural strings into the pump and calculating the probability of passing. Plurality sewage pumps of different types were evaluated based

  11. Liquid metals pumping

    International Nuclear Information System (INIS)

    Le Frere, J.P.

    1984-01-01

    Pumps used to pump liquid metals depend on the liquid metal and on the type of application concerned. One deals more particularly with electromagnetic pumps, the main pumps used with mechanical pumps. To pump sodium in the nuclear field, these two types of pumps are used; the pumps of different circuits of Super Phenix are presented and described [fr

  12. Pulsatile fluidic pump demonstration and predictive model application

    International Nuclear Information System (INIS)

    Morgan, J.G.; Holland, W.D.

    1986-04-01

    Pulsatile fluidic pumps were developed as a remotely controlled method of transferring or mixing feed solutions. A test in the Integrated Equipment Test facility demonstrated the performance of a critically safe geometry pump suitable for use in a 0.1-ton/d heavy metal (HM) fuel reprocessing plant. A predictive model was developed to calculate output flows under a wide range of external system conditions. Predictive and experimental flow rates are compared for both submerged and unsubmerged fluidic pump cases

  13. METHODS OF IMPROVING THE MUD PUMP VALVE LIFE

    Directory of Open Access Journals (Sweden)

    Miruna BĂLTĂREȚU IANCU

    2015-11-01

    Full Text Available Petroleum drilling rigs are used for identifying geologic reservoirs and for creating wells for extraction. The mud pumps of drilling rigs are operated at high mud rates to make possible the drilling process. The durability of the mud pump valves to erosive wear, due to the action of abrasive drilling fluid containing solid particles, depends on their constructive form and on the mud flow velocity. This paper analyzes a few methods of increasing the wear resistance of mud pump valves.

  14. The Na{sup +}/K{sup +} -pump in rat peritoneal mast cells: Some aspects of regulatio of activity and cellular fusion

    Energy Technology Data Exchange (ETDEWEB)

    Knudsen, T. [Odense Univ., Dept. of Pharmacology, Inst. of Medical Biology, The Faculty of Health Scineces (Denmark)

    1995-12-31

    The mast cell contains potent mediators of inflammation which are released after IgE-directed and non-IgE-directed stimulation of the cell. This highly specialized cell is therefore ascribed a role in the pathogenesis of disease states in which the inflammatory response plays a role for the development of the clinical symptoms. Thus, besides being of interest in basic research, studies of the cellular processes leading to release of inflammatory mediators from the mast cell also also have important clinical implications. The aim of the present work has been to document the existence of the Na{sup +}/K{sup +}-pump in rat peritoneal mast cells, to investigate the regulation of the pump activity and to explore whether modulation of the pump activity interferes with the cellular stimulus/secretion coupling mechanism. The Na{sup +}/K{sup +}-pump activity following stimulation of the mast cell was also investigated. The pump activity was assessed as the ouabain-sensitive cellular potassium uptake with {sup 86}Rb{sup +} as a tracer for potassium. The histamine release from the mast cell following IgE-directed and non-IgE-directed stimulation of the cell was used as a parameter of cellular degranulation. Histamine was measured by spectrofluorometry. Besides describing aspects of the function and regulation of the Na{sup +}/K{sup +}-pump in the rat peritoneal mast cell, this thesis points to the potential role of sodium transport mechanisms in mast cell physiology. Pharmacological manipulations of such transport mechanisms might in the future add to the treatment of allergic diseases. (au) 253 refs.

  15. Theoretical study of flow ripple for an aviation axial-piston pump with damping holes in the valve plate

    Directory of Open Access Journals (Sweden)

    Guan Changbin

    2014-02-01

    Full Text Available Based on the structure of a certain type of aviation axial-piston pump’s valve plate which adopts a pre-pressurization fluid path (consisting a damping hole, a buffer chamber, and an orifice to reduce flow ripple, a single-piston model of the aviation axial-piston pump is presented. This single-piston model comprehensively considers fluid compressibility, orifice restriction effect, fluid resistance in the capillary tube, and the leakage flow. Besides, the instantaneous discharge areas used in the single-piston model have been calculated in detail. Based on the single-piston model, a multi-piston pump model has been established according to the simple hydraulic circuit. The single- and multi-piston pump models have been realized by the S-function in Matlab/Simulink. The developed multi-piston pump model has been validated by being compared with the numerical result by computational fluid dynamic (CFD. The effects of the pre-pressurization fluid path on the flow ripple and the instantaneous pressure in the piston chamber have been studied and optimized design recommendations for the aviation axial-piston pump have been given out.

  16. On the energy release rate in a turbulent current sheet on the Sun

    International Nuclear Information System (INIS)

    Bardakov, V.M.

    1986-01-01

    It is shown that turbulent current sheets on the Sun, realizing in the form of the Parker - Sweet flow, are in quasilinear regime of turbulence (or in the regime of instability threshold). The energy release rate in such sheets does not exceed 10 26 erg/s for typical plasma parameters in active regions

  17. Evaluation of Ocimum basilicum L. seed mucilage as rate controlling matrix for sustained release of propranolol HCl

    Directory of Open Access Journals (Sweden)

    Majid Saeedi

    2015-01-01

    Full Text Available Polysaccharide mucilage derived from the seeds of Ocimum basilicum L. (family Lamiaceae was investigated for use in matrix formulations containing propranolol hydrochloride. Basil mucilage was extracted and several tablets were formulated. The effect of mucilage on drug release rate was evaluated in comparison with tablets containing two kinds of hydroxypropyl methylcellulose (HPMC K4M and HPMC K100M as standard polymer. The release data were fitted to several models for kinetic evaluation. The results showed that hardness decreased and friability of tablets increased as the concentration of mucilage increased. The rate of release of propranolol HCl from O. basilicm mucilage matrices was mainly controlled by the drug: mucilage ratio. Drug release was slower from the HPMC K4M and HPMCK100M containing tablets compared to the mucilage containing matrices than the drug release from matrices containing O. basilicum seed mucilage in similar ratios.  Formulations containing O. basilicm mucilage were found to exhibit suitable release pattern. The results of kinetic analysis showed that in tablets containing O. basilicm mucilage the highest correlation coefficient was achieved with the zero order model. The swelling and erosion studies revealed that, as the proportion of mucilage in tablets was increased, there was a corresponding increase in percent swelling and a decrease in percent erosion of tablets.

  18. Release of lysosomal enzymes in Candida albicans phagocytosis by rat peritoneal macrophages.

    Science.gov (United States)

    Fontenla de Petrino, S E; Sirena, A

    1984-02-15

    The present paper reports the in vitro release of lysosomal enzymes in the supernatant of cultures of rat peritoneal macrophages, with the addition of Candida albicans cells. Macrophages were taken from the rat peritoneal cavity 72 hr after non-specific activation with Brain-Heart-Infusion (B.H.I.) broth containing 10% proteose-peptone No. 3. They were then cultured in Parker medium No. 199 (TC 199). After 24 hr a suspension of Candida albicans cells, in a determined concentration, was added to the peritoneal macrophage cultures. At that time, and during pre-determined periods, the following enzymes in the culture supernatants were studied using colorimetric methods: beta-glucuronidase, beta-galactosidase and acid phosphatase. It is concluded that, under identical conditions, the release of beta-galactosidase and acid phosphatase is higher than for beta-glucuronidase. The release rate of all three enzymes is the highest at a 6 hr incubation period, after which, a gradual decrease leads to the rate down to 50% at 24 hr.

  19. Lymphatic pump treatment mobilizes leukocytes from the gut associated lymphoid tissue into lymph.

    Science.gov (United States)

    Hodge, Lisa M; Bearden, Melissa K; Schander, Artur; Huff, Jamie B; Williams, Arthur; King, Hollis H; Downey, H Fred

    2010-06-01

    Lymphatic pump techniques (LPT) are used clinically by osteopathic practitioners for the treatment of edema and infection; however, the mechanisms by which LPT enhances lymphatic circulation and provides protection during infection are not understood. Rhythmic compressions on the abdomen during LPT compress the abdominal area, including the gut-associated lymphoid tissues (GALT), which may facilitate the release of leukocytes from these tissues into the lymphatic circulation. This study is the first to document LPT-induced mobilization of leukocytes from the GALT into the lymphatic circulation. Catheters were inserted into either the thoracic or mesenteric lymph ducts of dogs. To determine if LPT enhanced the release of leukocytes from the mesenteric lymph nodes (MLN) into lymph, the MLN were fluorescently labeled in situ. Lymph was collected during 4 min pre-LPT, 4 min LPT, and 10 min following cessation of LPT. LPT significantly increased lymph flow and leukocytes in both mesenteric and thoracic duct lymph. LPT had no preferential effect on any specific leukocyte population, since neutrophil, monocyte, CD4+ T cell, CD8+ T cell, IgG+B cell, and IgA+B cell numbers were similarly increased. In addition, LPT significantly increased the mobilization of leukocytes from the MLN into lymph. Lymph flow and leukocyte counts fell following LPT treatment, indicating that the effects of LPT are transient. LPT mobilizes leukocytes from GALT, and these leukocytes are transported by the lymphatic circulation. This enhanced release of leukocytes from GALT may provide scientific rationale for the clinical use of LPT to improve immune function.

  20. Tritium Aspects of Fueling and Exhaust Pumping in Magnetic Fusion Energy

    Energy Technology Data Exchange (ETDEWEB)

    Baylor, Larry R. [ORNL; Meitner, Steven J. [ORNL

    2017-04-01

    Magnetically confined fusion plasmas generate energy from deuterium-tritium (DT) fusion reactions that produce energetic 3.5 MeV alpha particles and 14 MeV neutrons. Since the DT fusion reaction rate is a strong function of plasma density, an efficient fueling source is needed to maintain high plasma density in such systems. Energetic ions in fusion plasmas are able to escape the confining magnetic fields at a much higher rate than the fusion reactions occur, thus dictating the fueling rate needed. These lost ions become neutralized and need to be pumped away as exhaust gas to be reinjected into the plasma as fuel atoms.The technology to fuel and pump fusion plasmas has to be inherently compatible with the tritium fuel. An ideal holistic solution would couple the pumping and fueling such that the pump exhaust is directly fed back into pellet formation without including impurity gases. This would greatly reduce the processing needs for the exhaust. Concepts to accomplish this are discussed along with the fueling and pumping needs for a DT fusion reactor.

  1. An alternative arrangement of metered dosing fluid using centrifugal pump

    Science.gov (United States)

    Islam, Md. Arafat; Ehsan, Md.

    2017-06-01

    Positive displacement dosing pumps are extensively used in various types of process industries. They are widely used for metering small flow rates of a dosing fluid into a main flow. High head and low controllable flow rates make these pumps suitable for industrial flow metering applications. However their pulsating flow is not very suitable for proper mixing of fluids and they are relatively more expensive to buy and maintain. Considering such problems, alternative techniques to control the fluid flow from a low cost centrifugal pump is practiced. These include - throttling, variable speed drive, impeller geometry control and bypass control. Variable speed drive and impeller geometry control are comparatively costly and the flow control by throttling is not an energy efficient process. In this study an arrangement of metered dosing flow was developed using a typical low cost centrifugal pump using bypass flow technique. Using bypass flow control technique a wide range of metered dosing flows under a range of heads were attained using fixed pump geometry and drive speed. The bulk flow returning from the system into the main tank ensures better mixing which may eliminate the need of separate agitators. Comparative performance study was made between the bypass flow control arrangement of centrifugal pump and a diaphragm type dosing pump. Similar heads and flow rates were attainable using the bypass control system compared to the diaphragm dosing pump, but using relatively more energy. Geometrical optimization of the centrifugal pump impeller was further carried out to make the bypass flow arrangement more energy efficient. Although both the systems run at low overall efficiencies but the capital cost could be reduced by about 87% compared to the dosing pump. The savings in capital investment and lower maintenance cost very significantly exceeds the relatively higher energy cost of the bypass system. This technique can be used as a cost effective solution for

  2. A new hydraulic regulation method on district heating system with distributed variable-speed pumps

    International Nuclear Information System (INIS)

    Wang, Hai; Wang, Haiying; Zhu, Tong

    2017-01-01

    Highlights: • A hydraulic regulation method was presented for district heating with distributed variable speed pumps. • Information and automation technologies were utilized to support the proposed method. • A new hydraulic model was developed for distributed variable speed pumps. • A new optimization model was developed based on genetic algorithm. • Two scenarios of a multi-source looped system was illustrated to validate the method. - Abstract: Compared with the hydraulic configuration based on the conventional central circulating pump, a district heating system with distributed variable-speed-pumps configuration can often save 30–50% power consumption on circulating pumps with frequency inverters. However, the hydraulic regulations on distributed variable-speed-pumps configuration could be more complicated than ever while all distributed pumps need to be adjusted to their designated flow rates. Especially in a multi-source looped structure heating network where the distributed pumps have strongly coupled and severe non-linear hydraulic connections with each other, it would be rather difficult to maintain the hydraulic balance during the regulations. In this paper, with the help of the advanced automation and information technologies, a new hydraulic regulation method was proposed to achieve on-site hydraulic balance for the district heating systems with distributed variable-speed-pumps configuration. The proposed method was comprised of a new hydraulic model, which was developed to adapt the distributed variable-speed-pumps configuration, and a calibration model with genetic algorithm. By carrying out the proposed method step by step, the flow rates of all distributed pumps can be progressively adjusted to their designated values. A hypothetic district heating system with 2 heat sources and 10 substations was taken as a case study to illustrate the feasibility of the proposed method. Two scenarios were investigated respectively. In Scenario I, the

  3. Installation and initial operation of the DIII-D advanced divertor cryocondensation pump

    International Nuclear Information System (INIS)

    Smith, J.P.; Schaubel, K.M.; Baxi, C.B.; Campbell, G.L.; Hyatt, A.W.; Laughon, G.J.; Mahdavi, M.A.; Reis, E.E.; Schaffer, M.J.; Sevier, D.L.; Stambaugh, R.D.; Menon, M.M.

    1993-10-01

    Phase two of a divertor cryocondensation pump, the Advanced Divertor Program, is now installed in the DIII-D tokamak at General Atomics and complements the phase one biasable ring electrode. The installation consists of a 10 m long cryocondensation pump located in the divertor baffle chamber to study plasma density control by pumping of the divertor. The design is a toroidally electrically continuous liquid helium-cooled panel with 1 m 2 of pumping surface. The helium panel is single point grounded to the nitrogen shield to minimize eddy currents. The nitrogen shield is toroidally continuous and grounded to the vacuum vessel in 24 locations to prevent voltage potentials from building up between the pump and vacuum vessel wall. A radiation/particle shield surrounds the nitrogen-cooled surface to minimize the heat load and prevent water molecules condensed on the nitrogen surface from being released by impact of energetic particles. Large currents (>5000 A) are driven in the helium and nitrogen panels during ohmic coil ramp up and during disruptions. The pump is designed to accommodate both the thermal and mechanical loads due to these currents. A feedthrough for the cryogens allows for both radial and vertical motion of the pump with respect to the vacuum vessel. Thermal performance measured on a prototype verified the analytical model and thermal design of the pump. Characterization tests of the installed pump show the pumping speed in deuterium is 42,000 ell/sec for a pressure of 5 mTorr. Induction heating of the pump (at 300 W) resulted in no degradation of pumping speed. Plasma operations with the cryopump show a 60% lower density in H-mode

  4. The effect of gas release on column separator

    NARCIS (Netherlands)

    Kranenburg, C.

    1974-01-01

    A mathematical model has been considered in which the influence of gas release on transient cavitating flow and column separation in pipel ines is taken into account. A rei iable numerical method has been developed for the computation of the wave propagation and cavitation phenomena following pump

  5. Electromagnetic circulation pump for corrosive gases

    International Nuclear Information System (INIS)

    Noe, P.; Delafosse, D.; Deletre, G.

    1965-01-01

    In order to transport very corrosive products (fluorinated compounds) we have been led to develop a totally metallic circulation pump capable of operating at above room temperatures and with a molecular vacuum. We have aimed at maximum simplicity both in its conception and in its operation. The tests showed that the compression ratios produced, although not high are interesting (1.5 at a pressure of 100 torr) (see curve I). The flow-rate range is very wide: about one hundred ccs/atm/min. to 3000 ccs/atm/min. (see curves IV, V, VI). The desorption of this pump presents no difficulty if both the aspiration and the reject sides are pumped together. A hole of 2 mm diameter drilled in the piston makes it possible to desorb the space between the two segments. The price of this pump is not high: 1300 F, with the electrical cabinet. (authors) [fr

  6. Continuously pumping and reactivating gas pump

    International Nuclear Information System (INIS)

    Batzer, T.H.; Call, W.R.

    1984-01-01

    Apparatus for continuous pumping using cycling cyropumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels the alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independent pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped

  7. Continuously pumping and reactivating gas pump

    Science.gov (United States)

    Batzer, Thomas H.; Call, Wayne R.

    1984-01-01

    Apparatus for continuous pumping using cycling cyropumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels the alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independent pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped.

  8. Porous PDMS structures for the storage and release of aqueous solutions into fluidic environments.

    Science.gov (United States)

    Thurgood, Peter; Baratchi, Sara; Szydzik, Crispin; Mitchell, Arnan; Khoshmanesh, Khashayar

    2017-07-11

    Typical microfluidic systems take advantage of multiple storage reservoirs, pumps and valves for the storage, driving and release of buffers and other reagents. However, the fabrication, integration, and operation of such components can be difficult. In particular, the reliance of such components on external off-chip equipment limits their utility for creating self-sufficient, stand-alone microfluidic systems. Here, we demonstrate a porous sponge made of polydimethylsiloxane (PDMS), which is fabricated by templating microscale water droplets using a T-junction microfluidic structure. High-resolution microscopy reveals that this sponge contains a network of pores, interconnected by small holes. This unique structure enables the sponge to passively release stored solutions very slowly. Proof-of-concept experiments demonstrate that the sponge can be used for the passive release of stored solutions into narrow channels and circular well plates, with the latter used for inducing intracellular calcium signalling of immobilised endothelial cells. The release rate of stored solutions can be controlled by varying the size of interconnecting holes, which can be easily achieved by changing the flow rate of the water injected into the T-junction. We also demonstrate the active release of stored liquids into a fluidic channel upon the manual compression of the sponge. The developed PDMS sponge can be easily integrated into complex micro/macro fluidic systems and prepared with a wide array of reagents, representing a new building block for self-sufficient microfluidic systems.

  9. Profound regulation of Na/K pump activity by transient elevations of cytoplasmic calcium in murine cardiac myocytes.

    Science.gov (United States)

    Lu, Fang-Min; Deisl, Christine; Hilgemann, Donald W

    2016-09-14

    Small changes of Na/K pump activity regulate internal Ca release in cardiac myocytes via Na/Ca exchange. We now show conversely that transient elevations of cytoplasmic Ca strongly regulate cardiac Na/K pumps. When cytoplasmic Na is submaximal, Na/K pump currents decay rapidly during extracellular K application and multiple results suggest that an inactivation mechanism is involved. Brief activation of Ca influx by reverse Na/Ca exchange enhances pump currents and attenuates current decay, while repeated Ca elevations suppress pump currents. Pump current enhancement reverses over 3 min, and results are similar in myocytes lacking the regulatory protein, phospholemman. Classical signaling mechanisms, including Ca-activated protein kinases and reactive oxygen, are evidently not involved. Electrogenic signals mediated by intramembrane movement of hydrophobic ions, such as hexyltriphenylphosphonium (C6TPP), increase and decrease in parallel with pump currents. Thus, transient Ca elevation and Na/K pump inactivation cause opposing sarcolemma changes that may affect diverse membrane processes.

  10. Serial assessment of the physiological status of leatherback turtles (Dermochelys coriacea) during direct capture events in the northwestern Atlantic Ocean: comparison of post-capture and pre-release data.

    Science.gov (United States)

    Innis, Charles J; Merigo, Constance; Cavin, Julie M; Hunt, Kathleen; Dodge, Kara L; Lutcavage, Molly

    2014-01-01

    The physiological status of seven leatherback turtles (Dermochelys coriacea) was assessed at two time points during ecological research capture events in the northwestern Atlantic Ocean. Data were collected as soon as possible after securing each turtle onboard the capture vessel and again immediately prior to release. Measured parameters included sea surface temperature, body temperature, morphometric data, sex, heart rate, respiratory rate and various haematological and blood biochemical variables. Results indicated generally stable physiological status in comparison to previously published studies of this species. However, blood pH and blood potassium concentrations increased significantly between the two time points (P = 0.0018 and P = 0.0452, respectively). Turtles were affected by a mild initial acidosis (mean [SD] temperature-corrected pH = 7.29 [0.07]), and blood pH increased prior to release (mean [SD] = 7.39 [0.07]). Initial blood potassium concentrations were considered normal (mean [SD] = 4.2 [0.9] mmol/l), but turtles experienced a mild to moderate increase in blood potassium concentrations during the event (mean [SD] pre-release potassium = 5.9 [1.7] mmol/l, maximum = 8.5 mmol/l). While these data support the general safety of direct capture for study of this species, the observed changes in blood potassium concentrations are of potential concern due to possible adverse effects of hyperkalaemia on cardiac function. The results of this study highlight the importance of physiological monitoring during scientific capture events. The results are also likely to be relevant to unintentional leatherback capture events (e.g. fisheries interactions), when interactions may be more prolonged or extreme.

  11. Effect of pump limiter throat on pumping efficiency

    International Nuclear Information System (INIS)

    Ghendrih, P.; Grosman, A.; Samain, A.; Capes, H.; Morera, J.P.

    1988-01-01

    The necessary control of plasma edge density has led to the development of pump limiters to achieve this task. On Tore Supra, where a large part of the program is devoted to plasma edge studies, two types of such density control apparatus have been implemented, a set of pump limiters and the pumps associated to the ergodic divertor (magnetically assisted pump limiters). Generally two different kinds of pump limiters can be used, those with a throat which drives the plasma from the open edge plasma (SOL) to the neutralizer plate, and those without or with a very short throat. We are interested here in this aspect of the pump limiter concept, i.e. on the throat effect on neutral density build-up in the vicinity of the pumping plates (and hence on pumping efficieny). The underlying idea of this throat effect can be readily understood; indeed while the neutral capture in pump limiters without throats is only a ballistic effect, on expects the plasma to improve the efficiency of pump-limiters via plasma-neutral-sidewall interactions in the throat. This problem has been studied both numerically and analytically. The paper is divided as follows. In section 2, we describe the basic features of pump-limiters which are modelized by the numerical code Cezanne. Section 3 is devoted to the throat length effect considering in particular the neutral density profile in the throat and the neutral density buil-up as a function of the throat lenght. In section 4, we show that the plugging effect occurs for reasonnable values of throat lengths. An analytical value of the plugging length is discussed and compared to the values obtained numerically

  12. Selective attenuation of norepinephrine release and stress-induced heart rate increase by partial adenosine A1 agonism.

    Directory of Open Access Journals (Sweden)

    Lorenz Bott-Flügel

    Full Text Available The release of the neurotransmitter norepinephrine (NE is modulated by presynaptic adenosine receptors. In the present study we investigated the effect of a partial activation of this feedback mechanism. We hypothesized that partial agonism would have differential effects on NE release in isolated hearts as well as on heart rate in vivo depending on the genetic background and baseline sympathetic activity. In isolated perfused hearts of Wistar and Spontaneously Hypertensive Rats (SHR, NE release was induced by electrical stimulation under control conditions (S1, and with capadenoson 6 · 10(-8 M (30 µg/l, 6 · 10(-7 M (300 µg/l or 2-chloro-N(6-cyclopentyladenosine (CCPA 10(-6 M (S2. Under control conditions (S1, NE release was significantly higher in SHR hearts compared to Wistar (766+/-87 pmol/g vs. 173+/-18 pmol/g, p<0.01. Capadenoson led to a concentration-dependent decrease of the stimulation-induced NE release in SHR (S2/S1  =  0.90 ± 0.08 with capadenoson 6 · 10(-8 M, 0.54 ± 0.02 with 6 · 10(-7 M, but not in Wistar hearts (S2/S1  =  1.05 ± 0.12 with 6 · 10(-8 M, 1.03 ± 0.09 with 6 · 10(-7 M. CCPA reduced NE release to a similar degree in hearts from both strains. In vivo capadenoson did not alter resting heart rate in Wistar rats or SHR. Restraint stress induced a significantly greater increase of heart rate in SHR than in Wistar rats. Capadenoson blunted this stress-induced tachycardia by 45% in SHR, but not in Wistar rats. Using a [(35S]GTPγS assay we demonstrated that capadenoson is a partial agonist compared to the full agonist CCPA (74+/-2% A(1-receptor stimulation. These results suggest that partial adenosine A(1-agonism dampens stress-induced tachycardia selectively in rats susceptible to strong increases in sympathetic activity, most likely due to a presynaptic attenuation of NE release.

  13. 46 CFR 28.815 - Bilge pumps, bilge piping, and dewatering systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Bilge pumps, bilge piping, and dewatering systems. 28... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.815 Bilge pumps, bilge... fixed, self priming, powered, bilge pump, having a minimum capacity rating of 50 gallons per minute...

  14. Polar representation of centrifugal pump homologous curves

    International Nuclear Information System (INIS)

    Veloso, Marcelo Antonio; Mattos, Joao Roberto Loureiro de

    2008-01-01

    Essential for any mathematical model designed to simulate flow transient events caused by pump operations is the pump performance data. The performance of a centrifugal pump is characterized by four basic parameters: the rotational speed, the volumetric flow rate, the dynamic head, and the hydraulic torque. Any one of these quantities can be expressed as a function of any two others. The curves showing the relationships between these four variables are called the pump characteristic curves, also referred to as four-quadrant curves. The characteristic curves are empirically developed by the pump manufacturer and uniquely describe head and torque as functions of volumetric flow rate and rotation speed. Because of comprising a large amount of points, the four-quadrant configuration is not suitable for computational purposes. However, it can be converted to a simpler form by the development of the homologous curves, in which dynamic head and hydraulic torque ratios are expressed as functions of volumetric flow and rotation speed ratios. The numerical use of the complete set of homologous curves requires specification of sixteen partial curves, being eight for the dynamic head and eight for the hydraulic torque. As a consequence, the handling of homologous curves is still somewhat complicated. In solving flow transient problems that require the pump characteristic data for all the operation zones, the polar form appears as the simplest way to represent the homologous curves. In the polar method, the complete characteristics of a pump can be described by only two closed curves, one for the dynamic head and other for the hydraulic torque, both in function of a single angular coordinate defined adequately in terms of the quotient between volumetric flow ratio and rotation speed ratio. The usefulness and advantages of this alternative method are demonstrated through a practical example in which the homologous curves for a pump of the type used in the main coolant loops of a

  15. Experimentally reduced corticosterone release promotes early breeding in black-legged kittiwakes.

    Science.gov (United States)

    Goutte, Aurélie; Clément-Chastel, Céline; Moe, Børge; Bech, Claus; Gabrielsen, Geir Wing; Chastel, Olivier

    2011-06-15

    Breeding at the right time is important for successful reproduction. In birds, stressful environmental conditions are known to delay the timing of breeding but the underlying mechanisms are poorly understood. The stress hormone corticosterone appears to be a good candidate for mediating egg-laying date according to early environmental conditions and physiological state. By experimentally reducing the release of corticosterone in black-legged kittiwakes during the pre-laying period, we tested whether egg-laying date was mechanistically linked to corticosterone levels. Male and female kittiwakes were implanted with a low dose of exogenous corticosterone to inhibit endogenous corticosterone production. According to our predictions, the experimental reduction of corticosterone release was paralleled by a significant advancement of egg laying in females (around 4 days earlier). In addition, females with experimentally reduced corticosterone release gained mass during the pre-laying period compared with controls. Ultimately, the advancement of egg laying in females with experimentally reduced corticosterone levels was associated with an enhanced breeding success. This effect was strongly sex specific. In corticosterone-treated male kittiwakes, egg-laying date and reproductive success were not affected, but breeding probability was lower than in controls. This corticosterone treatment did not influence immediate clutch size, or return rate and breeding decision the following year. Our results support the hypothesis that corticosterone secretion during the pre-laying period mediates the timing of breeding in this long-lived seabird, possibly through the dynamics of energy reserves.

  16. High-efficiency diode-pumped femtosecond Yb:YAG ceramic laser

    DEFF Research Database (Denmark)

    Zhou, Binbin; Wei, Z.Y.; Zou, Y.W.

    2010-01-01

    A highly efficient diode-end-pumped femtosecond Yb:yttrium aluminum garnet (YAG) ceramic laser was demonstrated. Pumped by a 968 nm fiber-coupled diode laser, 1.9 W mode-locked output power at a repetition rate of 64.27 MHz was obtained with 3.5 W absorbed pump power, corresponding to a slope...... efficiency of 76%. Our measurement showed that the pulse duration was 418 fs with the central wavelength of 1048 nm....

  17. Experimental Assessment of Water Sprays Utilization for Controlling Hydrogen Sulfide Releases in Confined Space

    Directory of Open Access Journals (Sweden)

    Dongfeng Zhao

    2015-01-01

    Full Text Available This paper reported the utilization of water spray for controlling H2S release in a confined space, which is especially important in industry. A typical spray tower was modified to simulate the confined space for people's enterable routine operation (e.g., pump room, in which the dilution capacity of water sprays can also be evaluated. This work consists of two parts: the first part focuses on the influences of different operating conditions on chemical dilution capacities of water sprays in mechanisms; the second one is comparison between two nozzle configurations for evaluating their feasibilities of practical application. Water sprays express eligible performance for H2S release control even though their dilution capacity was weakened at high gaseous concentrations and rates of releases. The presence of Na2CO3 can significantly improve absorption effectiveness of H2S in water and the optimal Na2CO3 additive was found to be 1.0 g·L−1 in this test. Compared with Na2CO3, adjusting water flow rate may be an effective strategy in enhancing dilution capacity of water sprays due to the fact that larger flow rate led to both less dilution time (TD and dilution concentration (CD. Furthermore, multinozzle configuration is more efficient than single-nozzle configuration under the same water consumption.

  18. Commissioning result of the KSTAR in-vessel cryo-pump

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y. B.; Lee, H. J.; Park, Y.M. [National Fusion Research Institute, Daejeon (Korea, Republic of); and others

    2013-12-15

    KSTAR in-vessel cryo-pump has been installed in the vacuum vessel top and bottom side with up-down symmetry for the better plasma density control in the D-shape H-mode. The cryogenic helium lines of the in-vessel cryo-pump are located at the vertical positions from the vacuum vessel torus center 2,000 mm. The inductive electrical potential has been optimized to reduce risk of electrical breakdown during plasma disruption. In-vessel cryo-pump consists of three parts of coaxial circular shape components; cryo-panel, thermal shield and particle shield. The cryo-panel is cooled down to below 4.5 K. The cryo-panel and thermal shields were made by Inconel 625 tube for higher mechanical strength. The thermal shields and their cooling tubes were annealed in air environment to improve the thermal radiation emissivity on the surface. Surface of cryo-panel was electro-polished to minimize the thermal radiation heat load. The in-vessel cryo-pump was pre-assembled on a test bed in 180 degree segment base. The leak test was carried out after the thermal shock between room temperature to LN2 one before installing them into vacuum vessel. Two segments were welded together in the vacuum vessel and final leak test was performed after the thermal shock. Commissioning of the in-vessel cryo-pump was carried out using a temporary liquid helium supply system.

  19. Baxter elastomeric pumps: Weighing as an alternative to visual inspection.

    Science.gov (United States)

    Cusano, Ellen L; Ali, Raafi; Sawyer, Michael B; Chambers, Carole R; Tang, Patricia A

    2018-04-01

    Purpose Elastomeric pumps are used to administer 46-hour infusions of 5-fluorouracil (5FU). Baxter suggests patients visually monitor their pumps to ensure that infusions are proceeding correctly. This can be confusing and lead to concerns about under- or over-dosing. Baxter has not considered weighing pumps as a validated method for monitoring. This study aims to validate weighing as a more accurate method for patients and healthcare professionals, and describe real life Baxter Infusor™ variability. Methods Patients who had been started on a 46-hour 5FU infusion returned to the clinic approximately 24 h after starting treatment. The pump was weighed on a StarFrit kitchen scale, and date, time, and weights recorded. Patients were asked if they had a preference for weighing or visually inspecting their pump. Results Pumps ( n = 103) were weighed between 17.25 and 27.5 h after connection. The average weight of a pump was 189 g. Of 103 pumps weighed, 99 weighed less than expected, corresponding to average flow rates of 5.69 mL/h over the elapsed time. The expected flow rate is 5 mL/h with 10% variability. Average flow rates within the 17.25- to 27.5-hour window were 4.561 mL/h, which is 8.78% slower than expected, but within the 10% known variability. Forty-seven percent of patients didn't have a preference for either method, but for those who did have a preference, more than twice as many preferred weighing. Conclusion With proper education, weighing Baxter Infusors at home with kitchen scales can be an accepted and objective alternative to the current recommendation of visual inspection.

  20. NERATOOM work on pump development

    International Nuclear Information System (INIS)

    Hoornweg, C.J.

    1976-01-01

    The prototype pump has been manufactured by Stork Engineerings Works at Hengelo in 1969. The full-scale test on water has been carried out as part of the procedures of acceptance. Tests on sodium have been carried out in the pumptestfacility of Interatom at Bensberg (W. Germany); these tests started in March 1971 and were finished in October 1972. During that period nearly 6000 hours of pump testing were accomplished, of which 150 hours the pump was subjected to cavitation. During 30 hours the pump was subjected to a cavitation intensity of more than 3% loss of delivery head. At some occasions the loss of delivery head was 7%. The measured NPSH with the tests on sodium was 10m, whereas the NPSH obtained with the tests on water was 9m. Attempts have been made to account for this difference of NPSH-setting on the two liquids concerned. At the end of the tests on sodium (that is after the excecution of the cavitation tests) the delivery head of the pump was 2 m.l.c. less than the rated value. After dismantling the pump it appeared that the surface of the impeller vanes was roughened, especially at those parts where the original sand cast surface had not been polished. Based on the testresults and not being contradicted by calculation-results so far, our opinion is that cavitation in sodium of reactor temperature (550 0 C) most probably is of the same order of magnitude as it is in water of roomtemperature under the same conditions of NPSH, provided the same pump operates in systems that are exact replica of one another

  1. Optimization of an artificial-recharge-pumping system for water supply in the Maghaway Valley, Cebu, Philippines

    Science.gov (United States)

    Kawo, Nafyad Serre; Zhou, Yangxiao; Magalso, Ronnell; Salvacion, Lasaro

    2018-05-01

    A coupled simulation-optimization approach to optimize an artificial-recharge-pumping system for the water supply in the Maghaway Valley, Cebu, Philippines, is presented. The objective is to maximize the total pumping rate through a system of artificial recharge and pumping while meeting constraints such as groundwater-level drawdown and bounds on pumping rates at each well. The simulation models were coupled with groundwater management optimization to maximize production rates. Under steady-state natural conditions, the significant inflow to the aquifer comes from river leakage, whereas the natural discharge is mainly the subsurface outflow to the downstream area. Results from the steady artificial-recharge-pumping simulation model show that artificial recharge is about 20,587 m3/day and accounts for 77% of total inflow. Under transient artificial-recharge-pumping conditions, artificial recharge varies between 14,000 and 20,000 m3/day depending on the wet and dry seasons, respectively. The steady-state optimisation results show that the total optimal abstraction rate is 37,545 m3/day and artificial recharge is increased to 29,313 m3/day. The transient optimization results show that the average total optimal pumping rate is 36,969 m3/day for the current weir height. The transient optimization results for an increase in weir height by 1 and 2 m show that the average total optimal pumping rates are increased to 38,768 and 40,463 m3/day, respectively. It is concluded that the increase in the height of the weir can significantly increase the artificial recharge rate and production rate in Maghaway Valley.

  2. Preliminary validation of a new magnetic wireless blood pump.

    Science.gov (United States)

    Kim, Sung Hoon; Ishiyama, Kazushi; Hashi, Shuichiro; Shiraishi, Yasuyuki; Hayatsu, Yukihiro; Akiyama, Masatoshi; Saiki, Yoshikatsu; Yambe, Tomoyuki

    2013-10-01

    In general, a blood pump must be small, have a simple configuration, and have sufficient hydrodynamic performance. Herein, we introduce new mechanisms for a wireless blood pump that is small and simple and provides wireless and battery-free operation. To achieve wireless and battery-free operation, we implement magnetic torque and force control methods that use two external drivers: an external coil and a permanent magnet with a DC-motor, respectively. Power harvesting can be used to drive an electronic circuit for wireless monitoring (the observation of the pump conditions and temperature) without the use of an internal battery. The power harvesting will be used as a power source to drive other electronic devices, such as various biosensors with their driving circuits. To have both a compact size and sufficient pumping capability, the fully magnetic impeller has five stages and each stage includes four backward-curved blades. The pump has total and inner volumes of 20 and 9.8 cc, respectively, and weighs 52 g. The pump produces a flow rate of approximately 8 L/min at 80 mm Hg and the power generator produces 0.3 W of electrical power at 120 Ω. The pump also produces a minimum flow rate of 1.5 L/min and a pressure of 30 mm Hg for circulation at a maximum distance of 7.5 cm. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  3. Detection of low-level environmental exposure rates due to noble gas releases from the Muehleberg nuclear power plant

    International Nuclear Information System (INIS)

    Czarnecki, J.; Volkle, H.; Pretre, S.

    1980-01-01

    The increase of radiation doses in the vicinity of the Swiss Nuclear Power Stations due to airborne releases is generally expected to be below one mrem/year (about one percent of the natural radiation dose). To prove this expected rate, long term measurements with pressure ionization chambers in the vicinity of the Muhleberg plant (BWR) were conducted. Two of these chambers were installed at places where the greatest dose rates from the noble gas plumes were expected in the two prevailing wind directions. The local dose rates were continuously registered on magnetic tape to allow minicomputer evaluation. After the fuel change in the summer of 1976 the noble gas releases from Muhleberg dropped considerably. From that time the noble gas releases consisted of a very low continuous component and some rare short-time spike compoments resulting from turbine and reactor trips. The dose due to the low continuous component was determined by correlating the dose rates at the measuring points with the release measure--ments at the stack and with weather conditions, and by subtracting the natural background. The short noble gas spikes lasted from minutes to some hours and caused small dose rate increases which were easily measured with the ionization chambers, and usually amounted to doses of some microroentgens. By further correlating these dose peaks with wind direction and stack emission measurements, determination of short time atmospheric dilution factors for existing weather situations became possible. By this process, the very low annual environmental doses in the range of 1 mrem per year were determined. (author)

  4. Pumping and leak detection system of the HL-2A

    International Nuclear Information System (INIS)

    Cao Zeng; Xu Yunxian; Fu Weidong

    2001-01-01

    The pumping system is a combination of 8 turbomolecular pumps with three stages pumping for HL-2A vacuum vessel, a total effective pumping speed at the vessel of 12 m 3 ·s -1 for nitrogen. The leak detection of element and vessel is performed with inspiration, case of leak detection and two mass spectrometry. The total leak rate of vessel is bellow 1 x 10 -5 Pa ·m 3 ·s -1 . The base pressure is 1 x 10 -5 Pa

  5. Determination of Volumetric Losses in Hydrodynamic Pump Using Numerical Modelling

    Directory of Open Access Journals (Sweden)

    Lukáš ZAVADIL

    2012-06-01

    Full Text Available This paper deals with the numerical modelling of the flow in the single-stage centrifugal pump. The main objective is to determine leakage losses through annular seals at the suction side of the pump. Leakage through a shaft seal is not included in the simulation. The amount of liquid that circulates from the impeller discharge back to suction of the pump is determined in dependence on the flow rate. Losses in the pump are further discussed as well as the possibility of their prediction.

  6. Effect of detention basin release rates on flood flows - Application of a model to the Blackberry Creek Watershed in Kane County, Illinois

    Science.gov (United States)

    Soong, David T.; Murphy, Elizabeth A.; Straub, Timothy D.

    2009-01-01

    The effects of stormwater detention basins with specified release rates are examined on the watershed scale with a Hydrological Simulation Program - FORTRAN (HSPF) continuous-simulation model. Modeling procedures for specifying release rates from detention basins with orifice and weir discharge configurations are discussed in this report. To facilitate future detention modeling as a tool for watershed management, a chart relating watershed impervious area to detention volume is presented. The report also presents a case study of the Blackberry Creek watershed in Kane County, Ill., a rapidly urbanizing area seeking to avoid future flood damages from increased urbanization, to illustrate the effects of various detention basin release rates on flood peaks and volumes and flood frequencies. The case study compares flows simulated with a 1996 land-use HSPF model to those simulated with four different 2020 projected land-use HSPF model scenarios - no detention, and detention basins with release rates of 0.08, 0.10, and 0.12 cubic feet per second per acre (ft3/s-acre), respectively. Results of the simulations for 15 locations, which included the downstream ends of all tributaries and various locations along the main stem, showed that a release rate of 0.10 ft3/s-acre, in general, can maintain postdevelopment 100-year peak-flood discharge at a similar magnitude to that of 1996 land-use conditions. Although the release rate is designed to reduce the 100-year peak flow, reduction of the 2-year peak flow is also achieved for a smaller proportion of the peak. Results also showed that the 0.10 ft3/s-acre release rate was less effective in watersheds with relatively high percentages of preexisting (1996) development than in watersheds with less preexisting development.

  7. Changes in basal rates and bolus calculator settings in insulin pumps during pregnancy in women with type 1 diabetes

    DEFF Research Database (Denmark)

    Mathiesen, Jonathan M; Secher, Anna L; Ringholm, Lene

    2014-01-01

    OBJECTIVE: To explore insulin pump settings in a cohort of pregnant women with type 1 diabetes on insulin pump therapy with a bolus calculator. METHODS: Twenty-seven women with type 1 diabetes on insulin pump therapy were included in this study. At 8, 12, 21, 27 and 33 weeks, insulin pump setting...

  8. Direct solar-pumped iodine laser amplifier

    Science.gov (United States)

    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.

  9. Centrifugal Force Based Magnetic Micro-Pump Driven by Rotating Magnetic Fields

    International Nuclear Information System (INIS)

    Kim, S H; Hashi, S; Ishiyama, K

    2011-01-01

    This paper presents a centrifugal force based magnetic micro-pump for the pumping of blood. Most blood pumps are driven by an electrical motor with wired control. To develop a wireless and battery-free blood pump, the proposed pump is controlled by external rotating magnetic fields with a synchronized impeller. Synchronization occurs because the rotor is divided into multi-stage impeller parts and NdFeB permanent magnet. Finally, liquid is discharged by the centrifugal force of multi-stage impeller. The proposed pump length is 30 mm long and 19 mm in diameter which much smaller than currently pumps; however, its pumping ability satisfies the requirement for a blood pump. The maximum pressure is 120 mmHg and the maximum flow rate is 5000ml/min at 100 Hz. The advantage of the proposed pump is that the general mechanical problems of a normal blood pump are eliminated by the proposed driving mechanism.

  10. Centrifugal Force Based Magnetic Micro-Pump Driven by Rotating Magnetic Fields

    Science.gov (United States)

    Kim, S. H.; Hashi, S.; Ishiyama, K.

    2011-01-01

    This paper presents a centrifugal force based magnetic micro-pump for the pumping of blood. Most blood pumps are driven by an electrical motor with wired control. To develop a wireless and battery-free blood pump, the proposed pump is controlled by external rotating magnetic fields with a synchronized impeller. Synchronization occurs because the rotor is divided into multi-stage impeller parts and NdFeB permanent magnet. Finally, liquid is discharged by the centrifugal force of multi-stage impeller. The proposed pump length is 30 mm long and19 mm in diameter which much smaller than currently pumps; however, its pumping ability satisfies the requirement for a blood pump. The maximum pressure is 120 mmHg and the maximum flow rate is 5000ml/min at 100 Hz. The advantage of the proposed pump is that the general mechanical problems of a normal blood pump are eliminated by the proposed driving mechanism.

  11. Laboratory evaluation of the emulsifying characteristics of pumps. [Bilge and ballast water oily wastes

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, A.C.; Guzdar, A.R.; Fiswell, D.R.

    1973-10-01

    The program was devoted to a laboratory investigation of the emulsifying characteristics of different pumps suitable for shipboard pumping of bilge and ballast water oily wastes. The tests were designed to investigate the effect of several parameters, such as oil type, input oil concentration, detergent, pump operating characteristics (pressure and flow rate), and salt versus fresh water, on emulsification. Tests were conducted on the Foster-Miller tests loop. No. 2 fuel oil, lubricating oil and No. 6 fuel oil were the oils tested at concentrations ranging from 1 to 10%. The oils were tested with and without the addition of 10% Gamlen D surfactant. The pumps used were a Parker Diaphragm pump, a Blackmer Sliding Vane pump, an Ingersoll Rand Centrifugal pump and a Deming Centrifugal pump. Pump pressure ranged from 10 to 60 psi and flow rate from 10 to 100 gpm. A total of 270 tests were conducted covering 198 different operating points, 108 concerning pump comparison, 54 concerning oil concentration and surfactant, and 45 concerning salt water.

  12. Optimum solar collector fluid flow rates

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    1996-01-01

    Experiments showed that by means of a standard electronically controlled pump, type UPE 2000 from Grundfos it is possible to control the flow rate in a solar collector loop in such a way that the flow rate is strongly influenced by the temperature of the solar collector fluid passing the pump....... The flow rate is increasing for increasing temperature.The flow rate at the high temperature level is typically 70 % greater than the flow rate at the low temperature level.Further, the energy consumption for the electronically controlled pump in a solar heating system will be somewhat smaller than...... the energy consumption of a normal ciculation pump in the solar heating system.Calculations showed that the highest thermal performances for small SDHW systems based on mantle tanks with constant volume flow rates in the solar collector loops are achieved if the flow rate is situated in the interval from 0...

  13. Dry vacuum pumps

    International Nuclear Information System (INIS)

    Sibuet, R

    2008-01-01

    For decades and for ultimate pressure below 1 mbar, oil-sealed Rotary Vane Pumps have been the most popular solution for a wide range of vacuum applications. In the late 80ies, Semiconductor Industry has initiated the development of the first dry roughing pumps. Today SC applications are only using dry pumps and dry pumping packages. Since that time, pumps manufacturers have developed dry vacuum pumps technologies in order to make them attractive for other applications. The trend to replace lubricated pumps by dry pumps is now spreading over many other market segments. For the Semiconductor Industry, it has been quite easy to understand the benefits of dry pumps, in terms of Cost of Ownership, process contamination and up-time. In this paper, Technology of Dry pumps, its application in R and D/industries, merits over conventional pumps and future growth scope will be discussed

  14. RETRAN analysis of inter-system LOCA within the primary coolant pump

    International Nuclear Information System (INIS)

    Gangadharan, A.; Pratt, G.F.

    1992-01-01

    One example of an inter-system loss of coolant accident is the failure of the tubing within the primary coolant pump (PCP) thermal barrier heat exchanger. Such a failure would result in the entry of primary coolant into the component cooling water (CCW) system. The primary coolant flowrate through the break would rapidly pressurize the CCW system when the relief valves are too small. The piping in the CCW system at Palisades has a low pressure rating. Failures in this system outside the containment boundary could lead to primary coolant release to the atmosphere. RETRAN-02 was used to perform a simulation of the break in the PCP integral heat exchanger. The model included a detailed nodalization of the Byron-Jackson primary coolant pump internals leading up to the CCW system relief valves. Preliminary studies show the need for increased relief capacity in the CCW system. A case was run using a larger relief valve. Critical flow in the system upstream of the relief valves maintains the pressures in those volumes above the CCW design pressure. The pressures downstream from the relief valves and outside containment will be at or below the design pressure. This paper presents the results of the transient analysis

  15. Off-Pump Versus On-Pump Coronary Artery Bypass Grafting

    DEFF Research Database (Denmark)

    Møller, Christian H; Steinbrüchel, Daniel A

    2014-01-01

    Coronary artery bypass grafting (CABG) remains the preferred treatment in patients with complex coronary artery disease. However, whether the procedure should be performed with or without the use of cardiopulmonary bypass, referred to as off-pump and on-pump CABG, is still up for debate....... Intuitively, avoidance of cardiopulmonary bypass seems beneficial as the systemic inflammatory response from extracorporeal circulation is omitted, but no single randomized trial has been able to prove off-pump CABG superior to on-pump CABG as regards the hard outcomes death, stroke or myocardial infarction....... In contrast, off-pump CABG is technically more challenging and may be associated with increased risk of incomplete revascularization. The purpose of the review is to summarize the current literature comparing outcomes of off-pump versus on-pump coronary artery bypass surgery....

  16. The effect of balance holes to centrifugal pump performance

    Science.gov (United States)

    Babayigit, O.; Ozgoren, M.; Aksoy, M. H.; Kocaaslan, O.

    2017-07-01

    The aim of this study is to analyze of a centrifugal pump with and without balance holes by using ANSYS-Fluent software. The pump used in the study is a commercial centrifugal pump consisting of two stages that is a model of Sempa Pump Company. Firstly, models of impeller, diffuser, suction and discharge sections of the centrifugal pump were separately drawn using Ansys and Solidworks software. Later, grid structures were generated on the flow volume of the pump. Turbulent flow volume was numerically solved by realizable k-є turbulence model. The flow analyses were focused on the centrifugal pump performance and the flow characteristics under different operational conditions with/without balance holes. Distributions of flow characteristics such as velocity and pressure distributions in the flow volume were also determined, numerically. The results of Computational Fluid Dynamics (CFD) with/without balance holes for the pump head and hydraulic efficiency on the design flow rate of 80 m3/h were found to be 81.5/91.3 m and 51.9/65.3%, respectively.

  17. Small-sized pump for the target chamber of the E-SUVI accelerator

    International Nuclear Information System (INIS)

    Borts, B.V.; Kravchenko, S.F.; Pisarev, G.V.; Rubashko, V.G.; Khorenko, V.K.

    1980-01-01

    The target chamber of the accelerator ESUVI is located at the high voltage end of the accelerating tube under the electrostatic generator conductor. The pumping out from the target chamber region has been performed through the accelerating tube its rate constituting 1.5 l/s which resulted in oxidation and contamination of the surface of irradiated targets in the course of the irradiation of chemically active materials. For obtaining high vacuum in a target chamber a small-size gettering-ionic pump of the ORBITRON type has been developed which operates in the autonomous mode. The pump pumping out rate in the pressure range 10 -5 -10 -7 mm Hg constitutes for air and nitrogen 20-25 l/s, ffor oxygen 30-40 l/s, for hydrogen 100-120 l/s. The pump weight without supply units is 2 kg. The pumps permits performing pressure indicator in the target chamber. Using the developed pump makes possible to decrease the target chamber pressure to 1x10 -6 mm Hg for active gases to 10 -8 -10 -9 mm Hg

  18. Implementation of an RHR/LPSI pump coupling retrofit program

    International Nuclear Information System (INIS)

    Dudiak, J.G.; Koch, R.P.; Orewyler, R.; Tipton, J.W.

    1994-01-01

    Nuclear plant operating experience has shown the RHR and LPSI services to be very demanding on pumps. The systems handle borated water at high temperatures and pressures with frequent step changes in both temperature and pressure. Additionally, the industry trend towards reduced flow rates during plant mid-loop (reduced inventory) conditions has resulted in extended pump operation at flow rates significantly below the pump best efficiency point flow. Operation at these low flow fates is known to cause high thrust loads and large shaft deflections. The combination of these and other factors have resulted in short mechanical seal life and short motor bearing life, thus requiring frequent pump and motor maintenance. For many nuclear plants, including Southern California Edison's (SCE) San Onofre Units 2 and 3, these pumps have represented a major operations and maintenance (O ampersand M) expenditure and a significant source of radiation exposure to plant personnel. SCE management determined that a pump upgrade was justified to reduce the O ampersand M costs and to improve plant availability. SCE decided to proceed with a pump retrofit program to improve the pump maintainability, reliability and availability. Installation was completed for four LPSI pumps at San Onofre Units 2 and 3 during the Cycle 7 refueling outages in 1993. A key to the program's success was the removal of many traditional supplier and customer barriers and revision of supplier and customer roles to create a unified team. This paper traces the RHR/LPSI retrofit program for San Onofre from problem identification to project implementation. The team approach used for this program and the lessons learned may be useful to other utilities and vendors when evaluating or implementing system and equipment upgrades

  19. A simulation-based analysis of variable flow pumping in ground source heat pump systems with different types of borehole heat exchangers: A case study

    International Nuclear Information System (INIS)

    Zarrella, Angelo; Emmi, Giuseppe; De Carli, Michele

    2017-01-01

    Highlights: • The work focuses on the variable flow in ground source heat pump systems. • The constant and variable speed circulation pumps in the ground loop are compared. • The constant temperature difference control across the heat pump is studied. • The variable flow affects the energy performance of the heat pump. • The constant temperature difference control offers an attractive energy saving. - Abstract: A simulation model of ground source heat pump systems has been used to investigate to what extent a variable flow of the heat-carrier fluid of the ground loop affects the energy efficiency of the entire system. The model contemporaneously considers the borehole heat exchangers, the heat pump, the building load, and the control strategies for the circulation pumps of the ground loop. A constant speed of the circulation pumps of the ground loop was compared with a variable flow controlled by means of a constant temperature difference across the heat pump on the ground side considering the load profile of an office building located in North Italy. The analysis was carried out for a single U-tube, double U-tube and coaxial pipe heat exchangers. The control strategies adopted to manage the flow rate of the heat-carrier fluid of the ground loop affect both the heat exchange rate of the borehole field and the heat pump’s long-term energy efficiency. The simulations show considerable differences in the system’s seasonal energy efficiency. The constant speed of the circulation pumps leads to the best results as far as the heat pump’s energy performance was concerned, but this advantage was lost because of the greater amount of electrical energy used by the circulation pumps; this, of course, affects the energy efficiency of the entire system. The optimal solution appears then to be a constant temperature difference in the heat-carrier fluid across the heat pump.

  20. Ion-sorption pumps with an electrostatic field

    International Nuclear Information System (INIS)

    Larionov, L.S.; Leksakov, O.P.; Serbinov, A.N.

    1979-01-01

    Parameters are investigated and the choise of optimal operation regimes is made to develop the construction and production of an ion-sorption pump with an electrostatic field (orbitron). Described is the construction of ''Orbitron'' type and the results of bench marks, given are optimal operation regimes, dependence of pumping-out rate on pressure and other parameters. Operarion experience of these pumps on EG-8, EG-5 electrostatic accelerators, as well as on the KGE-300 accelerator in JINR showed their reliable operation during a long period of time and service simplicity. The parameters of the operation regime little differed from those, obtained earlier during bench marks

  1. Combustion Heat Release Rate Comparison of Algae Hydroprocessed Renewable Diesel to F-76 in a Two-Stroke Diesel Engine

    Science.gov (United States)

    2013-06-01

    was recorded. Figure 14 shows the gauge on the rocker arm during calibration . Figure 14. Mechanical Injector Rocker Arm Strain Gauge. D. DATA...RELEASE RATE COMPARISON OF ALGAE HYDROPROCESSED RENEWABLE DIESEL TO F-76 IN A TWO-STROKE DIESEL ENGINE by John H. Petersen June 2013 Thesis...RELEASE RATE COMPARISON OF ALGAE HYDROPROCESSED RENEWABLE DIESEL TO F-76 IN A TWO-STROKE DIESEL ENGINE 5. FUNDING NUMBERS 6. AUTHOR(S) John H

  2. Investigation of pump and pump switch failures in rainwater harvesting systems

    Science.gov (United States)

    Moglia, Magnus; Gan, Kein; Delbridge, Nathan; Sharma, Ashok K.; Tjandraatmadja, Grace

    2016-07-01

    Rainwater harvesting is an important technology in cities that can contribute to a number of functions, such as sustainable water management in the face of demand growth and drought as well as the detention of rainwater to increase flood protection and reduce damage to waterways. The objective of this article is to investigate the integrity of residential rainwater harvesting systems, drawing on the results of the field inspection of 417 rainwater systems across Melbourne that was combined with a survey of householders' situation, maintenance behaviour and attitudes. Specifically, the study moves beyond the assumption that rainwater systems are always operational and functional and draws on the collected data to explore the various reasons and rates of failure associated with pumps and pump switches, leaving for later further exploration of the failure in other components such as the collection area, gutters, tank, and overflows. To the best of the authors' knowledge, there is no data like this in academic literature or in the water sector. Straightforward Bayesian Network models were constructed in order to analyse the factors contributing to various types of failures, including system age, type of use, the reason for installation, installer, and maintenance behaviour. Results show that a number of issues commonly exist, such as failure of pumps (5% of systems), automatic pump switches that mediate between the tank and reticulated water (9% of systems), and systems with inadequate setups (i.e. no pump) limiting their use. In conclusion, there appears to be a lack of enforcement or quality controls in both installation practices by sometimes unskilled contractors and lack of ongoing maintenance checks. Mechanisms for quality control and asset management are required, but difficult to promote or enforce. Further work is needed into how privately owned assets that have public benefits could be better managed.

  3. Evidence that the Na+-K+ leak/pump ratio contributes to the difference in endurance between fast- and slow-twitch muscles.

    Science.gov (United States)

    Clausen, T; Overgaard, K; Nielsen, O B

    2004-02-01

    Muscles containing predominantly fast-twitch (type II) fibres [ext. dig. longus (EDL)] show considerably lower contractile endurance than muscles containing mainly slow-twitch (type I) fibres (soleus). To assess whether differences in Na+-K+ fluxes and excitability might contribute to this phenomenon, we compared excitation-induced Na+-K+ leaks, Na+ channels, Na+-K+ pump capacity, force and compound action potentials (M-waves) in rat EDL and soleus muscles. Isolated muscles were mounted for isometric contractions in Krebs-Ringer bicarbonate buffer and exposed to direct or indirect continuous or intermittent electrical stimulation. The time-course of force decline and concomitant changes in Na+-K+ exchange and M-waves were recorded. During continuous stimulation at 60-120 Hz, EDL showed around fivefold faster rate of force decline than soleus. This was associated with a faster loss of excitability as estimated from the area and amplitude of the M-waves. The net uptake of Na+ and the release of K+ per action potential were respectively 6.5- and 6.6-fold larger in EDL than in soleus, which may in part be due to the larger content of Na+ channels in EDL. During intermittent stimulation with 1 s 60 Hz pulse trains, EDL showed eightfold faster rate of force decline than soleus. The considerably lower contractile endurance of fast-twitch compared with slow-twitch muscles reflects differences in the rate of excitation-induced loss of excitability. This is attributed to the much larger excitation-induced Na+ influx and K+ efflux, leading to a faster rise in [K+]o in fast-twitch muscles. This may only be partly compensated by the concomitant activation of the Na+-K+ pumps, in particular in fibres showing large passive Na+-K+ leaks or reduced content of Na+-K+ pumps. Thus, endurance depends on the leak/pump ratio for Na+ and K+.

  4. Arrayed architectures for multi-stage Si-micromachined high-flow Knudsen pumps

    International Nuclear Information System (INIS)

    Qin, Yutao; An, Seungdo; Gianchandani, Yogesh B

    2015-01-01

    This paper reports an evaluation and a comparison of two architectures for implementing Si-micromachined high-flow Knudsen pumps. Knudsen pumps, which operate on the principle of thermal transpiration, have been shown to have great promise for micro-scale gas phase fluidic systems such as micro gas chromatographs. Simultaneously achieving both a high flow rate and adequate blocking pressure has been a persistent challenge, which is addressed in this work by combining multiple pumps in series and addressing the resulting challenges in thermal management. The basic building block is a Si-micromachined pump with  ≈100 000 parallel channels in a 4 mm  ×  6 mm footprint. In the primary approach, multiple pump stages are stacked vertically with interleaved Si-micromachined spacers. A stacked 4-stage Knudsen pump has a form factor of 10 mm  ×  8 mm  ×  6 mm. In an alternate approach, multiple stages are arranged in a planar array. The experimental results demonstrate multiplication of the output pressure head with the number of stages, while the flow rate is maintained. For example, a stacked 4-stage Knudsen pump with 8 W power operated at atmospheric pressure provided a blocking pressure of 0.255 kPa, which was 3.6  ×  of that provided by a single-stage pump with 2 W power; while both provided a  ≈  30 sccm maximum flow rate. The performance can be customized for practical applications such as micro gas chromatography. (paper)

  5. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  6. Liquid metal pump

    Science.gov (United States)

    Pennell, William E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  7. Liquid metal pump

    International Nuclear Information System (INIS)

    Pennell, W.E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair

  8. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  9. Ventricular fibrillation occurring after atrioventricular node ablation despite minimal difference between pre- and post-ablation heart rates.

    Science.gov (United States)

    Squara, F; Theodore, G; Scarlatti, D; Ferrari, E

    2017-02-01

    We report the case of an 82-year-old man presenting with ventricular fibrillation (VF) occurring acutely after atrioventricular node (AVN) ablation. This patient had severe valvular cardiomyopathy, chronic atrial fibrillation (AF), and underwent prior to the AVN ablation a biventricular implantable cardiac defibrillator positioning. The VF was successfully cardioverted with one external electrical shock. What makes this presentation original is that the pre-ablation spontaneous heart rate in AF was slow (84 bpm), and that VF occurred after ablation despite a minimal heart rate drop of only 14 bpm. VF is the most feared complication of AVN ablation, but it had previously only been described in case of acute heart rate drop after ablation of at least 30 bpm (and more frequently>50 bpm). This case report highlights the fact that VF may occur after AVN ablation regardless of the heart rate drop, rendering temporary fast ventricular pacing mandatory whatever the pre-ablation heart rate. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Optimal installation of two heat pumps in a hotel

    Energy Technology Data Exchange (ETDEWEB)

    Groos, J

    1980-03-01

    In December 1979 a heat pump was brought into service in the hotel and restaurant 'Haus Baehner' in Niederfischbach. With the help of two heat pumps heat recovering measures are being achieved. Here it is a matter of water-to-water heat pumps, which work with, as the case may be, two compressors. These heat pumps are available in seven power categories between 8.2 and 63 kW rated power. The refrigerating circuit works with the safety-refrigerant R12 so that the removal of heat from a -15/sup 0/C medium is still possible. On the warm side, maximum temperatures up to 70/sup 0/C are possible.

  11. Employment of the porous particles for preparation of the capsules containing aspirin and drug release property

    International Nuclear Information System (INIS)

    Hosoi, Fumio; Makuuchi, Keizo; Saito, Kenji; Koishi, Masumi.

    1985-01-01

    Polymer-coated porous particles containing aspirin as a drug were prepared and the rate of release of aspirin was studied. The impregnation of aspirin was carried out by post-graft polymerization, where methyl methacrylate or methacrylic acid was treated with porous particles, pre-irradiated with γ-ray from 60 Co, in the presence of aspirin. Release of aspirin from modified particles was tested with 50 % methanol solution and/or pH 5.2 buffer solution of acetic acid. The amount of aspirin released from capsules increased with time and reached a constant values after 140 h. The amount of aspirin absorbed in porous particles was increased with graft polymerization. In addition, absorption of aspirin in porous particles was significantly enhanced by treating the particle surface with TiO 2 before irradiation. The amount of aspirin released was linearly to the square root of time. It was concluded that the diffusion of aspirin through the polymer matrix was the rate limiting step. (author)

  12. Investigation on the influence of jetting equipment on the characteristics of centrifugal pump

    Directory of Open Access Journals (Sweden)

    Qiaorui Si

    2016-08-01

    Full Text Available To reduce radial noises from the motor of centrifugal pumps, this study designed a water cooling system called jetting equipment to replace traditional fan cooling systems in pump motors. By measuring radiated noises, head, efficiency, and cavitation performance, the research compared the differences among experimental results of the original pump unit, the one with a normal design jetting pipe and another one with a larger jetting pipe. Results show that the radiated sound pressure level of the model pump was significantly reduced by 8.3 dB after integrating the jetting pipe. With a normal jetting pipe, no significant changes were observed in the head, efficiency, and shaft power curves, and cavitation performance improved under small flow rate. However, the performance with the larger jetting pipe worsened, except the hump phenomenon of the model pump under a small flow rate was enhanced. Computational fluid dynamics method was used to calculate the internal flow of three model pumps in order to investigate the jetting flow effect. A comparison among the flow fields at the inlet of the three types of pumps indicated that high-pressure water injection can effectively control inlet recirculation and improve velocity distribution in the inlet flow field with decreased recirculation vortex strength and recirculation onset critical flow rate.

  13. Experimental Study on Series Operation of Sliding Vane Pump and Centrifugal Pump

    OpenAIRE

    Li, Tao; Zhang, Weiming; Jiang, Ming; Li, Zhengyang

    2013-01-01

    A platform for sliding vane pump and centrifugal pump tests is installed to study the series operation of them under different characteristics of pipeline. Firstly, the sliding vane pump and the centrifugal pump work independently, and the performance is recorded. Then, the two types of pumps are combined together, with the sliding vane pump acting as the feeding pump. Comparison is made between the performance of the independently working pump and the performance of series operation pump. Re...

  14. Centrifugal pump handbook

    CERN Document Server

    Pumps, Sulzer

    2010-01-01

    This long-awaited new edition is the complete reference for engineers and designers working on pump design and development or using centrifugal pumps in the field. This authoritative guide has been developed with access to the technical expertise of the leading centrifugal pump developer, Sulzer Pumps. In addition to providing the most comprehensive centrifugal pump theory and design reference with detailed material on cavitation, erosion, selection of materials, rotor vibration behavior and forces acting on pumps, the handbook also covers key pumping applications topics and operational

  15. Controlled release studies of calcium alginate hydrogels

    International Nuclear Information System (INIS)

    Rendevski, S.; Andonovski, A.; Mahmudi, N.

    2012-01-01

    Controlled release of substances in many cases may be achieved from calcium alginate hydrogels. In this research, the time dependence of the mass of released model substance bovine serum albumin (BSA) from calcium alginate spherical hydrogels of three different types (G/M ratio) have been investigated. The hydrogels were prepared with the drop-wise method of sodium alginate aqueous solutions with concentration of 0.02 g/cm 3 with 0.01 g/cm 3 BSA and a gelling water bath of chitosan in 0.2 M CH 3 COOH/0.4 M CH 3 COONa with added 0.2 M CaCl 2 .The hydrogel structures were characterized by dynamic light scattering and scanning electron microscopy. The controlled release studies were conducted by UV-Vis spectrophotometry of the released medium with p H=7 at 37 °C. The results showed that the model of osmotic pumping is the dominant mechanism of the release. Also, large dependences of the release profile on the homogeneity of the hydrogels were found. (Author)

  16. 3D printing of tablets containing multiple drugs with defined release profiles.

    Science.gov (United States)

    Khaled, Shaban A; Burley, Jonathan C; Alexander, Morgan R; Yang, Jing; Roberts, Clive J

    2015-10-30

    We have employed three-dimensional (3D) extrusion-based printing as a medicine manufacturing technique for the production of multi-active tablets with well-defined and separate controlled release profiles for three different drugs. This 'polypill' made by a 3D additive manufacture technique demonstrates that complex medication regimes can be combined in a single tablet and that it is viable to formulate and 'dial up' this single tablet for the particular needs of an individual. The tablets used to illustrate this concept incorporate an osmotic pump with the drug captopril and sustained release compartments with the drugs nifedipine and glipizide. This combination of medicines could potentially be used to treat diabetics suffering from hypertension. The room temperature extrusion process used to print the formulations used excipients commonly employed in the pharmaceutical industry. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and X-ray powder diffraction (XRPD) were used to assess drug-excipient interaction. The printed formulations were evaluated for drug release using USP dissolution testing. We found that the captopril portion showed the intended zero order drug release of an osmotic pump and noted that the nifedipine and glipizide portions showed either first order release or Korsmeyer-Peppas release kinetics dependent upon the active/excipient ratio used. Copyright © 2015. Published by Elsevier B.V.

  17. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    International Nuclear Information System (INIS)

    Killeen, J.C.

    1997-01-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12μm grain size fuel. Both large grain size variants had similar grain sizes around 35μm. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of 85 Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs

  18. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    Energy Technology Data Exchange (ETDEWEB)

    Killeen, J C [Nuclear Electric plc, Barnwood (United Kingdom)

    1997-08-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12{mu}m grain size fuel. Both large grain size variants had similar grain sizes around 35{mu}m. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of {sup 85}Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs.

  19. CFD Analysis of a Centrifugal Pump with Supercritical Carbon Dioxide as a Working Fluid

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Gu; Lee, Jeong Ik; Ahn, Yoonhan; Lee, Jekyoung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Cha, Jae Eun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Addad, Yacine [Khalifa Univ. of Science Technology and Research, Abu Dhabi (United Arab Emirates)

    2013-05-15

    The research team is conducting a S-CO{sub 2} pump experiment to obtain fundamental data for the advanced pump design and measure the overall performance of the pump near the critical point. The S-CO{sub 2} pump testing loop configuration is similar to SNL and JAEA testing loop while the operating conditions and focus of experiment are different from other test facilities. This paper presents the methodology of a 3-dimensional flow analysis for the S-CO{sub 2} pump by using the commercial CFD code. In Figure 2, the results at the 1.5kg/s mass flow rate seems to be close agreement between the CFD efficiency and S-CO{sub 2} test results. In the low mass flow rate of 1.0kg/s, CFD predicted 17∼25% higher efficiency than the test result. In the real test facility, the steel structure of pump is not an adiabatic wall and also the mechanical losses such as suction, blade loading and leakage exist in the pump. The reason why CFD analysis showed higher pump efficiency at the low mass flow is the above mentioned losses were excluded from the model. However, as the mass flow rate increases these have less effect on the efficiency. If the heat transfer through the structure and pump losses are applied in the analysis, other losses can be estimated. From the S-CO{sub 2} pump experiment, more data will be obtained and compared to the CFD analyses under the methodology presented in this paper. After the fluid behavior in the pump are well understood, these analysis results will be used for optimizing impeller for advanced S-CO{sub 2} compressor design in the future. However, it is very encouraging that even at very small mass flow rate the efficiency of S-CO{sub 2} pump near the critical point operation is very high compared to the manufacturer water test. The reason behind such phenomenon will be more carefully studied in the future.

  20. Particle removal with pump limiters in ISX-B

    International Nuclear Information System (INIS)

    Mioduszewski, P.; Emerson, L.C.; Simpkins, J.E.

    1983-01-01

    First pump limiter experiments were performed on ISX-B. Two pump limiter modules were installed in the top and bottom of one toroidal sector of the tokamak. The modules consist of inertia cooled, TiC coated graphite heads and Zr-Al getter pumps each with a pumping speed of 1000 to 2000 l/s. The objective of the initial experiments was the demonstration of plasma particle control with pump limiters. The first set of experiments were performed in ohmic discharges (OH) in which the effect of the pump limiters on the plasma density was clearly demonstrated. In discharges characterized by: I/sub p/ = 110 kA, B/sub T/ = 15 kG, anti n/sub e/ = 1 - 5 x 10 13 cm -3 and t = 0.3 s the pressure rise in the pump limiters was typically 2 mTorr with the pumps off and 0.7 mTorr after activating the pumps. When the pumps were activated, the line-average plasma density decreased by up to a factor 2 at identical gas flow rates. The second set of measurements were performed in neutral beam heated discharges (NBI) with injected powers between 0.6 MW and 1.0 MW. Due to a cooling problem on one of the Zr-Al pumps the NBI experiments were carried out with one limiter only. The maximum pressure observed in NBI-discharges was 5 mTorr without activating the pumps, i.e., approximately twice as high as in OH-discharges. The exhaust efficiency, which is defined as the removed particle flux over the total particle flux in the scrape-off layer is estimated to be 5%

  1. Penis Pump

    Science.gov (United States)

    ... your appointment might be less involved. Choosing a penis pump Some penis pumps are available without a ... it doesn't get caught in the ring. Penis pumps for penis enlargement Many advertisements in magazines ...

  2. Pumping characteristics of sputter ion pump (SIP) and titanium sublimation pump (TSP) combination

    International Nuclear Information System (INIS)

    Ratnakala, K.C.; Patel, R.J.; Bhavsar, S.T.; Pandiyar, M.L.; Ramamurthi, S.S.

    1995-01-01

    For achieving hydrocarbon free, clean ultra high vacuum, SIP-TSP combination is one of the ideal choice for pumping. For the SRS facility in Centre for Advanced Technology (CAT), we are utilising this combination, enmass. For this purpose, two modules of these combination set-ups are assembled, one with the TSP as an integral part of SIP and the other, with TSP as a separate pump mounted on the top of SIP. The pump bodies were vacuum degassed at 700 degC at 10 -5 mbar for 3 hrs. An ultimate vacuum of 3 x 10 -11 mbar was achieved, after a bake-out at 250 degC for 4 hrs, followed by continuous SIP pumping for 48 hrs, with two TSP flashing at approximately 10 hrs interval. The pump-down patterns as well as the pressure-rise patterns are studied. (author). 2 refs., 5 figs

  3. Predicting performance of a ground-source heat pump system using fuzzy weighted pre-processing-based ANFIS

    Energy Technology Data Exchange (ETDEWEB)

    Esen, Hikmet; Esen, Mehmet [Department of Mechanical Education, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey); Inalli, Mustafa [Department of Mechanical Engineering, Faculty of Engineering, Firat University, 23279 Elazig (Turkey); Sengur, Abdulkadir [Department of Electronic and Computer Science, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey)

    2008-12-15

    The goal of this work is to predict the daily performance (COP) of a ground-source heat pump (GSHP) system with the minimum data set based on an adaptive neuro-fuzzy inference system (ANFIS) with a fuzzy weighted pre-processing (FWP) method. To evaluate the effectiveness of our proposal (FWP-ANFIS), a computer simulation is developed on MATLAB environment. The comparison of the proposed hybridized system's results with the standard ANFIS results is carried out and the results are given in the tables. The efficiency of the proposed method was demonstrated by using the 3-fold cross-validation test. The statistical methods, such as the root-mean squared (RMS), the coefficient of multiple determinations (R{sup 2}) and the coefficient of variation (cov), are given to compare the predicted and actual values for model validation. The average R{sup 2} values is 0.9998, the average RMS value is 0.0272 and the average cov value is 0.7733, which can be considered as very promising. The data set for the COP of GSHP system available included 38 data patterns. The simulation results show that the FWP-based ANFIS can be used in an alternative way in these systems. The prediction results of the proposed structure were much better than the standard ANFIS results. Therefore, instead of limited experimental data found in the literature, faster and simpler solutions are obtained using hybridized structures such as FWP-based ANFIS. (author)

  4. Drug release kinetic analysis and prediction of release data via polymer molecular weight in sustained release diltiazem matrices.

    Science.gov (United States)

    Adibkia, K; Ghanbarzadeh, S; Mohammadi, G; Khiavi, H Z; Sabzevari, A; Barzegar-Jalali, M

    2014-03-01

    This study was conducted to investigate the effects of HPMC (K4M and K100M) as well as tragacanth on the drug release rate of diltiazem (DLTZ) from matrix tablets prepared by direct compression method.Mechanism of drug transport through the matrices was studied by fitting the release data to the 10 kinetic models. 3 model independent parameters; i. e., mean dissolution time (MDT), mean release rate (MRR) and release rate efficacy (RE) as well as 5 time point approaches were established to compare the dissolution profiles. To find correlation between fraction of drug released and polymer's molecular weight, dissolution data were fitted into two proposed equations.All polymers could sustain drug release up to 10 h. The release data were fitted best to Peppas and Higuchi square root kinetic models considering squared correlation coefficient and mean percent error (MPE). RE and MRR were decreased when polymer to drug ratio was increased. Conversely, t60% was increased with raising polymer /drug ratio. The fractions of drug released from the formulations prepared with tragacanth were more than those formulated using the same amount of HPMC K4M and HPMC K100M.Preparation of DLTZ matrices applying HPMCK4M, HPMC K100M and tragacanth could effectively extend the drug release. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Impact of surgeon experience on the rate of blood transfusion in off-pump coronary artery bypass.

    Science.gov (United States)

    Chen, Jeng-Wei; Hsu, Ron-Bin

    2016-03-01

    Off-pump coronary artery bypass (OPCAB) reduces the rate of blood transfusion. No studies have focused on the effect of surgeon experience on the transfusion rate. We sought to assess the transfusion rate in OPCAB and to evaluate the effect of surgeon experience. Retrospective review of 1055 consecutive patients undergoing OPCAB between 2000 and 2012. Patients were divided into tripartites by the year of operation (2000-2004, 2005-2008, and 2009-2012). Surgeon experience was evaluated with revascularization index and conversion rate. Mode of intervention was elective in 768, urgency in 185, and emergency in 102 patients (10%). Blood transfusion was associated with increased rates of hospital mortality and sternal wound/bloodstream infections. Revascularization index was 1.22 ± 0.29 per patient and increased over time, from 1.05 ± 0.21 in 2000-2004 to 1.39 ± 0.26 in 2009-2012. Conversion rate was 10% and decreased over time, from 17% in 2000-2004 to 6% in 2009-2012. The average rate of blood transfusion was 58% and decreased over time, from 74% in 2000-2004 to 41% in 2009-2012. Rate of red blood cell transfusion was 56% and decreased from 72% in 2000-2004 to 40% in 2009-2012. Rate of platelet transfusion was 21% and decreased from 25% in 2000-2004 to 15% in 2009-2012.The most significant decrease in the transfusion rate was observed in nonemergency cases. Surgeon experience reduced the need of blood transfusion after OPCAB. Increasing surgeon experience was associated with a 33% reduction in blood transfusion rate. Copyright © 2015. Published by Elsevier B.V.

  6. Intrinsic uncoupling of mitochondrial proton pumps. 2. Modeling studies.

    Science.gov (United States)

    Pietrobon, D; Zoratti, M; Azzone, G F; Caplan, S R

    1986-02-25

    The thermodynamic and kinetic properties associated with intrinsic uncoupling in a six-state model of a redox proton pump have been studied by computing the flow-force relations for different degrees of coupling. Analysis of these relations shows the regulatory influence of the thermodynamic forces on the extent and relative contributions of redox slip and proton slip. Inhibition has been introduced into the model in two different ways, corresponding to possible modes of action of experimental inhibitors. Experiments relating the rate of electron transfer to delta microH at static head upon progressive inhibition of the pumps have been simulated considering (1) the limiting case that the nonzero rate of electron transfer at static head is only due to intrinsic uncoupling (no leaks) and (2) the experimentally observed case that about 30% of the nonzero rate of electron transfer at static head is due to a constant proton leakage conductance in parallel with the pumps, the rest being due to intrinsic uncoupling. The same simulations have been performed for experiments in which the rate of electron transfer is varied by varying the substrate concentration rather than by using an inhibitor. The corresponding experimental results obtained by measuring delta microH and the rate of electron transfer at different succinate concentrations in rat liver mitochondria are presented. Comparison between simulated behavior and experimental results leads to the general conclusion that the typical relationship between rate of electron transfer and delta microH found in mitochondria at static head could certainly be a manifestation of some degree of intrinsic uncoupling in the redox proton pumps.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Electromagnetic linear pump for liquid-metal service

    International Nuclear Information System (INIS)

    Meisner, J.

    Electromagnetic pumps are not noted for their efficiency - values on the order of 15% are not unusual. However, the Energy Systems Group of Rockwell International, under contract to the Department of Energy, has recently designed, built, and tested for the Clinch River Breeder Reactor Program (CRBRP) a pump that has a peak efficiency of 40%. This outstanding efficiency was obtained by optimizing the hydraulic and electrical properties of the pumping section early in the design phase. These performance features were proven in a highly successful series of tests at flow rates up to 800 gal/min and temperatures up to 1130 0 F. This article discusses the design in detail and presents some of the test results

  8. Development and Characterization a Single-Active-Chamber Piezoelectric Membrane Pump with Multiple Passive Check Valves

    Directory of Open Access Journals (Sweden)

    Ronghui Zhang

    2016-12-01

    Full Text Available In order to prevent the backward flow of piezoelectric pumps, this paper presents a single-active-chamber piezoelectric membrane pump with multiple passive check valves. Under the condition of a fixed total number of passive check valves, by means of changing the inlet valves and outlet valves’ configuration, the pumping characteristics in terms of flow rate and backpressure are experimentally investigated. Like the maximum flow rate and backpressure, the testing results show that the optimal frequencies are significantly affected by changes in the number inlet valves and outlet valves. The variation ratios of the maximum flow rate and the maximum backpressure are up to 66% and less than 20%, respectively. Furthermore, the piezoelectric pump generally demonstrates very similar flow rate and backpressure characteristics when the number of inlet valves in one kind of configuration is the same as that of outlet valves in another configuration. The comparison indicates that the backflow from the pumping chamber to inlet is basically the same as the backflow from the outlet to the pumping chamber. No matter whether the number of inlet valves or the number of outlet valves is increased, the backflow can be effectively reduced. In addition, the backpressure fluctuation can be significantly suppressed with an increase of either inlet valves or outlet valves. It also means that the pump can prevent the backflow more effectively at the cost of power consumption. The pump is very suitable for conditions where more accurate flow rates are needed and wear and fatigue of check valves often occur.

  9. Development and Characterization a Single-Active-Chamber Piezoelectric Membrane Pump with Multiple Passive Check Valves.

    Science.gov (United States)

    Zhang, Ronghui; You, Feng; Lv, Zhihan; He, Zhaocheng; Wang, Haiwei; Huang, Ling

    2016-12-12

    In order to prevent the backward flow of piezoelectric pumps, this paper presents a single-active-chamber piezoelectric membrane pump with multiple passive check valves. Under the condition of a fixed total number of passive check valves, by means of changing the inlet valves and outlet valves' configuration, the pumping characteristics in terms of flow rate and backpressure are experimentally investigated. Like the maximum flow rate and backpressure, the testing results show that the optimal frequencies are significantly affected by changes in the number inlet valves and outlet valves. The variation ratios of the maximum flow rate and the maximum backpressure are up to 66% and less than 20%, respectively. Furthermore, the piezoelectric pump generally demonstrates very similar flow rate and backpressure characteristics when the number of inlet valves in one kind of configuration is the same as that of outlet valves in another configuration. The comparison indicates that the backflow from the pumping chamber to inlet is basically the same as the backflow from the outlet to the pumping chamber. No matter whether the number of inlet valves or the number of outlet valves is increased, the backflow can be effectively reduced. In addition, the backpressure fluctuation can be significantly suppressed with an increase of either inlet valves or outlet valves. It also means that the pump can prevent the backflow more effectively at the cost of power consumption. The pump is very suitable for conditions where more accurate flow rates are needed and wear and fatigue of check valves often occur.

  10. A well test analysis method accounting for pre-test operations

    International Nuclear Information System (INIS)

    Silin, D.B.; Tsang, C.-F.

    2003-01-01

    We propose to use regular monitoring data from a production or injection well for estimating the formation hydraulic properties in the vicinity of the wellbore without interrupting the operations. In our approach, we select a portion of the pumping data over a certain time interval and then derive our conclusions from analysis of these data. A distinctive feature of the proposed approach differing it form conventional methods is in the introduction of an additional parameter, an effective pre-test pumping rate. The additional parameter is derived based on a rigorous asymptotic analysis of the flow model. Thus, we account for the non-uniform pressure distribution at the beginning of testing time interval caused by pre-test operations at the well. By synthetic and field examples, we demonstrate that deviation of the matching curve from the data that is usually attributed to skin and wellbore storage effects, can also be interpreted through this new parameter. Moreover, with our method, the data curve is matched equally well and the results of the analysis remain stable when the analyzed data interval is perturbed, whereas traditional methods are sensitive to the choice of the data interval. A special efficient minimization procedure has been developed for searching the best fitting parameters. We enhanced our analysis above with a procedure of estimating ambient reservoir pressure and dimensionless wellbore radius. The methods reported here have been implemented in code ODA (Operations Data Analysis). A beta version of the code is available for free testing and evaluation to interested parties

  11. [Response of Algae to Nitrogen and Phosphorus Concentration and Quantity of Pumping Water in Pumped Storage Reservoir].

    Science.gov (United States)

    Wan, You-peng; Yin, Kui-hao; Peng, Sheng-hua

    2015-06-01

    Taking a pumped storage reservoir located in southern China as the research object, the paper established a three-dimensional hydrodynamic and eutrophication model of the reservoir employing EFDC (environmental fluid dynamics code) model, calibrated and verified the model using long-term hydraulic and water quality data. Based on the model results, the effects of nitrogen and phosphorus concentrations on the algae growth were analyzed, and the response of algae to nitrogen and phosphorus concentration and quantity of pumping water was also calculated. The results showed that the nitrogen and phosphorus concentrations had little limit on algae growth rate in the reservoir. In the nutrients reduction scenarios, reducing phosphorus would gain greater algae biomass reduction than reducing nitrogen. When reducing 60 percent of nitrogen, the algae biomass did not decrease, while 12.4 percent of algae biomass reduction could be gained with the same reduction ratio of phosphorus. When the reduction ratio went to 90 percent, the algae biomass decreased by 17.9 percent and 35.1 percent for nitrogen and phosphorus reduction, respectively. In the pumping water quantity regulation scenarios, the algae biomass decreased with the increasing pumping water quantity when the pumping water quantity was greater than 20 percent of the current value; when it was less than 20 percent, the algae biomass increased with the increasing pumping water quantity. The algae biomass decreased by 25.7 percent when the pumping water quantity was doubled, and increased by 38.8 percent when it decreased to 20 percent. The study could play an important role in supporting eutrophication controlling in water source area.

  12. Forecasting of a ground-coupled heat pump performance using neural networks with statistical data weighting pre-processing

    Energy Technology Data Exchange (ETDEWEB)

    Esen, Hikmet; Esen, Mehmet [Department of Mechanical Education, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey); Inalli, Mustafa [Department of Mechanical Engineering, Faculty of Engineering, Firat University, 23279 Elazig (Turkey); Sengur, Abdulkadir [Department of Electronic and Computer Science, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey)

    2008-04-15

    The objective of this work is to improve the performance of an artificial neural network (ANN) with a statistical weighted pre-processing (SWP) method to learn to predict ground source heat pump (GCHP) systems with the minimum data set. Experimental studies were completed to obtain training and test data. Air temperatures entering/leaving condenser unit, water-antifreeze solution entering/leaving the horizontal ground heat exchangers and ground temperatures (1 and 2 m) were used as input layer, while the output is coefficient of performance (COP) of system. Some statistical methods, such as the root-mean squared (RMS), the coefficient of multiple determinations (R{sup 2}) and the coefficient of variation (cov) is used to compare predicted and actual values for model validation. It is found that RMS value is 0.074, R{sup 2} value is 0.9999 and cov value is 2.22 for SCG6 algorithm of only ANN structure. It is also found that RMS value is 0.002, R{sup 2} value is 0.9999 and cov value is 0.076 for SCG6 algorithm of SWP-ANN structure. The simulation results show that the SWP based networks can be used an alternative way in these systems. Therefore, instead of limited experimental data found in literature, faster and simpler solutions are obtained using hybridized structures such as SWP-ANN. (author)

  13. System Design Description Salt Well Liquid Pumping Dynamic Simulation

    International Nuclear Information System (INIS)

    HARMSEN, R.W.

    1999-01-01

    The Salt Well Liquid (SWL) Pumping Dynamic Simulation used by the single-shell tank (SST) Interim Stabilization Project is described. A graphical dynamic simulation predicts SWL removal from 29 SSTs using an exponential function and unique time constant for each SST. Increasing quarterly efficiencies are applied to adjust the pumping rates during fiscal year 2000

  14. The Relationship between Toxics Release Inventory Discharges and Mortality Rates in Rural and Urban Areas of the United States

    Science.gov (United States)

    Hendryx, Michael; Fedorko, Evan

    2011-01-01

    Background: Potential environmental exposures from chemical manufacturing or industrial sites have not been well studied for rural populations. The current study examines whether chemical releases from facilities monitored through the Toxics Release Inventory (TRI) program are associated with population mortality rates for both rural and urban…

  15. High-power pre-chirp managed amplification of femtosecond pulses at high repetition rates

    International Nuclear Information System (INIS)

    Liu, Yang; Li, Wenxue; Zhao, Jian; Bai, Dongbi; Luo, Daping; Zeng, Heping

    2015-01-01

    Femtosecond pulses at 250 MHz repetition rate from a mode-locked fiber laser are amplified to high power in a pre-chirp managed amplifier. The experimental strategy offers a potential towards high-power ultrashort laser pulses at high repetition rates. By investigating the laser pulse evolution in the amplification processes, we show that self-similar evolution, finite gain bandwidth and mode instabilities determine pulse characteristics in different regimes. Further average power scaling is limited by the mode instabilities. Nevertheless, this laser system enables us to achieve sub-50 fs pulses with an average power of 93 W. (letter)

  16. Development of LMR Coolant Technology - Development of a submersible-in-pool electromagnetic pump

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sang Hi; Kim, Hee Reyoung; Lee, Sang Don; Seo, Joon Ho [Seoul National University, Seoul (Korea, Republic of); Cho, Su Won [Kyoungki University, Suwon (Korea, Republic of)

    1997-07-15

    A submersible-in-pool type annular linear induction pumps of 60 l/min and 200 l/min, and 600 deg C has been designed with optimum geometrical and operating values found from MHD and circuit analyses reflecting the high-temperature characteristics of pump materials. Through the characteristics analyses inside the narrow flow channel of electromagnetic pump, the distribution of the time-varying flow field is calculated, and magnetic flux and force density are evaluated by end effects of linear induction electromagnetic pump and the instability analyses are carried out introducing one-dimensional linear perturbation. Testing the pump with the flow rate of 60 l/min in the suitably manufactured loop system shows a flow rate of 58 l/min at an input power of 1,377 VA with 60Hz. The design of a scaled-up pump is further taken into account LMR coolant system requiring increased capacity, and a basic analysis is carried out on the pump of 40,000 l/min for KALIMER. The present project contributes to the further design of engineering prototype electromagnetic pumps with higher capacity and to the development of liquid metal reactor with innovative simplicity. 89 refs., 8 tabs., 45 figs. (author)

  17. A first-in-man study of the Reitan catheter pump for circulatory support in patients undergoing high-risk percutaneous coronary intervention.

    Science.gov (United States)

    Smith, Elliot J; Reitan, Oyvind; Keeble, Thomas; Dixon, Kerry; Rothman, Martin T

    2009-06-01

    To investigate the safety of a novel percutaneous circulatory support device during high-risk percutaneous coronary intervention (PCI). The Reitan catheter pump (RCP) consists of a catheter-mounted pump-head with a foldable propeller and surrounding cage. Positioned in the descending aorta the pump creates a pressure gradient, reducing afterload and enhancing organ perfusion. Ten consecutive patients requiring circulatory support underwent PCI; mean age 71 +/- 9; LVEF 34% +/- 11%; jeopardy score 8 +/- 2.3. The RCP was inserted via the femoral artery. Hemostasis was achieved using Perclose sutures. PCI was performed via the radial artery. Outcomes included in-hospital death, MI, stroke, and vascular injury. Hemoglobin (Hb), free plasma Hb (fHb), platelets, and creatinine (cre) were measured pre PCI and post RCP removal. The pump was inserted and operated successfully in 9/10 cases (median 79 min). Propeller rotation at 10,444 +/- 1,424 rpm maintained an aortic gradient of 9.8 +/- 2 mm Hg. Although fHb increased, there was no significant hemolysis (4.7 +/- 2.4 mg/dl pre vs. 11.9 +/- 10.5 post, P = 0.04, reference 20 mg/dl). Platelets were unchanged (pre 257 +/- 74 x 10(9) vs. 245 +/- 63, P = NS). Renal function improved (cre pre 110 +/- 27 micromol/l vs. 99 +/- 28, P = 0.004). The RCP was not used in one patient following femoral introducer sheath related aortic dissection. All PCI procedures were successful with no deaths or strokes, one MI, and no vascular complications following pump removal. The RCP can be used safely in high-risk PCI patients. This device may be an alternative to other percutaneous systems when substantial cardiac support is needed. (c) 2009 Wiley-Liss, Inc.

  18. Gyro-effect stabilizes unstable permanent maglev centrifugal pump.

    Science.gov (United States)

    Qian, Kun-Xi

    2007-03-01

    According to Earnshaw's Theorem (1839), the passive maglev cannot achieve stable equilibrium and thus an extra coil is needed to make the rotor electrically levitated in a heart pump. The author had developed a permanent maglev centrifugal pump utilizing only passive magnetic bearings, to keep the advantages but to avoid the disadvantages of the electric maglev pumps. The equilibrium stability was achieved by use of so-called "gyro-effect": a rotating body with certain high speed can maintain its rotation stably. This pump consisted of a rotor (driven magnets and an impeller), and a stator with motor coil and pump housing. Two passive magnetic bearings between rotor and stator were devised to counteract the attractive force between the motor coil iron core and the rotor driven magnets. Bench testing with saline demonstrated a levitated rotor under preconditions of higher than 3,250 rpm rotation and more than 1 l/min pumping flow. Rotor levitation was demonstrated by 4 Hall sensors on the stator, with evidence of reduced maximal eccentric distance from 0.15 mm to 0.07 mm. The maximal rotor vibration amplitude was 0.06 mm in a gap of 0.15 mm between rotor and stator. It concluded that Gyro-effect can help passive maglev bearings to achieve stabilization of permanent maglev pump; and that high flow rate indicates good hydraulic property of the pump, which helps also the stability of passive maglev pump.

  19. Mode-locked Ti:sapphire laser oscillators pumped by wavelength-multiplexed laser diodes

    Science.gov (United States)

    Sugiyama, Naoto; Tanaka, Hiroki; Kannari, Fumihiko

    2018-05-01

    We directly pumped a Ti:sapphire laser by combining 478 and 520 nm laser diodes to prevent the effect of absorption loss induced by the pump laser of shorter wavelengths (∼450 nm). We obtain a continuous-wave output power of 660 mW at a total incident pump power of 3.15 W. We demonstrate mode locking using a semiconductor saturable absorber mirror, and 126 fs pulses were obtained at a repetition rate of 192 MHz. At the maximum pump power, the average output power is 315 mW. Shorter mode-locked pulses of 42 and 48 fs were respectively achieved by Kerr-lens mode locking with average output powers of 280 and 360 mW at a repetition rate of 117 MHz.

  20. Scrape-off profiles and effects of limiter pumping in Tore Supra

    International Nuclear Information System (INIS)

    Budny, R.

    1986-11-01

    A one dimensional plasma scrape-off model was used to simulate Tore Supra discharges which are limited by various combinations of the pumped and inner limiters. Scrape-off profiles of the electron density and temperature, ion temperature, and neutral density are given. For each case, various fractions of the ion flux to the neutralizers were assumed to be pumped. Modifications of the scrap-off profiles caused by pumping are predicted. Pumping efficiencies are calculated including the effects of flux amplification caused by recycling. The pumping efficiency is estimated to be 8% for low-power discharges formed on the outer pumped limiter, 7.5% for intermediate-power discharges formed on the seven-module pumped-limiter system, and 5% for full-power discharges formed on both the inner limiter and the pumped-limiter system. The maximum particle removal rate is estimated to be 150 Tl/s

  1. Sol-Gel Based Polybenzimidazole Membranes for Hydrogen Pumping Devices

    Energy Technology Data Exchange (ETDEWEB)

    Benicewicz, Brian C. [Rensselaer Polytechnic Institute, Troy, NY (United States). Department of Chemistry and Chemical Biology; Eisman, Glenn A. [Rensselaer Polytechnic Institute, Troy, NY (United States). Department of Materials Science and Engineering; Kumar, S. K. [Columbia Univ., New York, NY (United States). Department of Chemical Engineering; Greenbaum, S. G. [Hunter College, New York, NY (United States). Department of Physics

    2014-02-26

    Electrochemical hydrogen pumping using a high temperature (>100°C) PBI membrane was demonstrated under non-humidified and humidified conditions at ambient pressures. Relatively low voltages were required to operate the pump over a wide range of hydrogen flow rates. The advantages of the high temperature capability were shown by operating the pump on reformate feed gas mixtures containing various amounts of CO and CO2. Gas purity measurements on the cathode gas product were conducted and significant reductions in gas impurities were detected. The applicability of the PBI membrane for electrochemical hydrogen pumping and its durability under typical operating conditions was established with tests that lasted for nearly 4000 hours.

  2. Maintenance of heartburn relief after step-down from twice-daily proton pump inhibitor to once-daily dexlansoprazole modified release.

    Science.gov (United States)

    Fass, Ronnie; Inadomi, John; Han, Cong; Mody, Reema; O'Neil, Janet; Perez, M Claudia

    2012-03-01

    Many patients with gastroesophageal reflux disease (GERD) take a proton pump inhibitor (PPI) twice daily to control symptoms. Once-daily dexlansoprazole modified release (MR) has a dual-delayed release formulation, making it attractive for step-down management of patients whose symptoms are well controlled on twice-daily PPIs. We investigated whether step-down to once-daily dexlansoprazole controls heartburn in patients with GERD who were receiving twice-daily PPI therapy. Patients 18 years and older taking a twice-daily PPI for symptom control were enrolled (n = 178) in a single-blind, multicenter study; 163 patients completed the study and 142 patients met criteria for the efficacy analysis. During the 6-week screening and treatment periods, patients recorded the presence of heartburn symptoms twice daily in electronic diaries. Patients' heartburn was considered well controlled if they had an average of 1 symptom or fewer per week during the last 4 weeks of screening and treatment. After screening, qualified patients were switched to masked dexlansoprazole MR 30 mg and placebo for 6 weeks. The primary efficacy end point was the proportion of patients whose heartburn remained well controlled after step-down. GERD-related symptoms and quality of life (QOL) also were evaluated using the Patient Assessment of Upper Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM) and the PAGI-QOL questionnaires, respectively. After step-down to once-daily dexlansoprazole MR 30 mg, heartburn remained well controlled in 88% of patients (125 of 142). These patients were able to maintain their GERD-related symptom severity and QOL, indicated by marginal changes in the PAGI-SYM and PAGI-QOL total and subscale scores, respectively. Most patients with GERD who take twice-daily PPI to control heartburn are able to successfully step down to once-daily dexlansoprazole 30 mg. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

  3. Effective Anti-miRNA Oligonucleotides Show High Releasing Rate of MicroRNA from RNA-Induced Silencing Complex.

    Science.gov (United States)

    Ariyoshi, Jumpei; Matsuyama, Yohei; Kobori, Akio; Murakami, Akira; Sugiyama, Hiroshi; Yamayoshi, Asako

    2017-10-01

    MicroRNAs (miRNAs) regulate gene expression by forming RNA-induced silencing complexes (RISCs) and have been considered as promising therapeutic targets. MiRNA is an essential component of RISC for the modulation of gene expression. Therefore, the release of miRNA from RISC is considered as an effective method for the inhibition of miRNA functions. In our previous study, we reported that anti-miRNA oligonucleotides (AMOs), which are composed of the 2'-O-methyl (2'-OMe) RNA, could induce the release of miRNA from RISC. However, the mechanisms underlying the miRNA-releasing effects of chemically modified AMOs, which are conventionally used as anti-cancer drugs, are still unclear. In this study, we investigated the relationship between the miRNA releasing rate from RISC and the inhibitory effect on RISC activity (IC 50 ) using conventional chemically modified AMOs. We demonstrated that the miRNA-releasing effects of AMOs are directly proportional to the IC 50 values, and AMOs, which have an ability to promote the release of miRNA from RISC, can effectively inhibit RISC activity in living cells.

  4. Centrifugal pumps

    CERN Document Server

    Gülich, Johann Friedrich

    2014-01-01

    This book gives an unparalleled, up-to-date, in-depth treatment of all kinds of flow phenomena encountered in centrifugal pumps including the complex interactions of fluid flow with vibrations and wear of materials. The scope includes all aspects of hydraulic design, 3D-flow phenomena and partload operation, cavitation, numerical flow calculations, hydraulic forces, pressure pulsations, noise, pump vibrations (notably bearing housing vibration diagnostics and remedies), pipe vibrations, pump characteristics and pump operation, design of intake structures, the effects of highly viscous flows, pumping of gas-liquid mixtures, hydraulic transport of solids, fatigue damage to impellers or diffusers, material selection under the aspects of fatigue, corrosion, erosion-corrosion or hydro-abrasive wear, pump selection, and hydraulic quality criteria. As a novelty, the 3rd ed. brings a fully analytical design method for radial impellers, which eliminates the arbitrary choices inherent to former design procedures. The d...

  5. FMECA about pre-treatment system for purge gas of test blanket module in ITER

    International Nuclear Information System (INIS)

    Fu Wanfa; Luo Deli; Tang Tao

    2012-01-01

    The pre-treatment system for purge gas of TBM will be installed in Port Cell for installing TBM in ITER, the function of which includes filtering purge gas, removing HTO, cooling, and adjusting flow rate, etc. The purge gas treated will be conveyed into TES (Tritium Extraction System). The technological process and system components in pre-treatment system were introduced. Tritium releasing risk was regarded as failure criterion; failure mode, effects and criticality analysis (FMECA) were carried out and several weaknesses or failure mode in the system were found. Besides, risk priority number (RPN) and failure mode criticality were calculated. Finally, some design improvement measures and usage compensation measures were given. At last, four important potential failure modes were found out. The analysis will provide the design basis for reducing risk of excessive tritium releasing, which is also a useful assist for safety analysis about other tritium system. (authors)

  6. Quantum mechanical features of optically pumped CW FIR lasers

    Science.gov (United States)

    Seligson, D.; Leite, J. R. R.; Sanchez, A.; Feld, M. S.; Ducloy, M.

    1977-01-01

    Quantum mechanical predictions for the gain of an optically pumped CW FIR laser are presented for cases in which one or both of the pump and FIR transitions are pressure or Doppler broadened. The results are compared to those based on the rate equation model. Some of the quantum mechanical predictions are verified in CH3OH.

  7. Study on solid-liquid two-phase unsteady flow characteristics with different flow rates in screw centrifugal pump

    International Nuclear Information System (INIS)

    Li, R N; Wang, H Y; Han, W; Shen, Z J; Ma, W

    2013-01-01

    The screw centrifugal pump is used as an object, and the unsteady numerical simulation of solid-liquid two-phase flow is carried out under different flow rate conditions in one circle by choosing the two-phase flow of sand and water as medium, using the software FLUENT based on the URANS equations, combining with sliding mesh method, and choosing the Mixture multiphase flow model and the SIMPLE algorithm. The results show that, with the flow rate increasing, the change trends for the pressure on volute outlet are almost constant, the fluctuation trends of the impeller axial force have a little change, the pressure and the axial force turn to decrease on the whole, the radial force gradually increases when the impeller maximum radius passes by half a cycle near the volute outlet, and the radial force gradually decreases when the maximum radius passes by the other half a cycle in a rotation cycle. The distributions of the solid particles are very uneven under a small flow rate condition on the face. The solid particles under a big flow rate condition are distributed more evenly than the ones under a small flow rate condition on the back. The theoretical basis and reference are provided for improving its working performance

  8. Using slow-release permanganate candles to remediate PAH-contaminated water.

    Science.gov (United States)

    Rauscher, Lindy; Sakulthaew, Chainarong; Comfort, Steve

    2012-11-30

    Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin-KMnO(4)) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2-4 h. Using (14)C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO(2)), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet-dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide proof-of-concept that permanganate candles could potentially provide a low-cost, low-maintenance approach to remediating PAH-contaminated water. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Pumping characteristics of roots blower pumps for light element gases

    International Nuclear Information System (INIS)

    Hiroki, Seiji; Abe, Tetsuya; Tanzawa, Sadamitsu; Nakamura, Jun-ichi; Ohbayashi, Tetsuro

    2002-07-01

    The pumping speed and compression ratio of the two-stage roots blower pumping system were measured for light element gases (H 2 , D 2 and He) and for N 2 , in order to assess validity of the ITER torus roughing system as an ITER R and D task (T234). The pumping system of an Edwards EH1200 (nominal pumping speed of 1200 m 3 /s), two EH250s (ibid. 250 m 3 /s) and a backing pump (ibid. 100 m 3 /s) in series connection was tested under PNEUROP standards. The maximum pumping speeds of the two-stage system for D 2 and N 2 were 1200 and 1300 m 3 /h, respectively at 60 Hz, which satisfied the nominal pumping speed. These experimental data support the design validity of the ITER torus roughing system. (author)

  10. Influence of the rate of conversion of HT and HTO on projected radiation doses from release of molecular tritium

    International Nuclear Information System (INIS)

    Jacobs, D.G.; Easterly, C.E.; Phillips, J.E.

    1979-01-01

    Releases of tritium in the past have been largely in the form of tritiated water, and the projected radiation doses could be estimated by assuming tritium behaviour to parallel that of water. There is increasing interest in potential releases of tritium in the form of HT because of significant recent advances in fusion reactor research. Several recent studies have shown that bacteria containing the enzyme hydrogenase can catalyse the conversion of HT to HTO at rates several orders of magnitude faster than the rates measured in atmospheric systems. Rates of conversion in the soil have been combined with estimates of rates of permeation of HT into the soil and with global and local models depicting tritium transport and cycling. The results suggest that for the expected conversion rates, the impact on projected radiation doses should be relatively minor. (author)

  11. Optical silencing of body wall muscles induces pumping inhibition in Caenorhabditis elegans

    OpenAIRE

    Takahashi, Megumi; Takagi, Shin

    2017-01-01

    Feeding, a vital behavior in animals, is modulated depending on internal and external factors. In the nematode Caenorhabditis elegans, the feeding organ called the pharynx ingests food by pumping driven by the pharyngeal muscles. Here we report that optical silencing of the body wall muscles, which drive the locomotory movement of worms, affects pumping. In worms expressing the Arch proton pump or the ACR2 anion channel in the body wall muscle cells, the pumping rate decreases after activatio...

  12. 14 CFR 1274.214 - Inquiries and release of information.

    Science.gov (United States)

    2010-01-01

    ... AGREEMENTS WITH COMMERCIAL FIRMS Pre-Award Requirements § 1274.214 Inquiries and release of information. NASA personnel shall follow the procedures established in NFS 1805.402 prior to releasing information to the news...

  13. A novel approach to biocontrol: Release of live insect hosts pre-infected with entomopathogenic nematodes.

    Science.gov (United States)

    Gumus, Arife; Karagoz, Mehmet; Shapiro-Ilan, David; Hazir, Selcuk

    2015-09-01

    As a new application approach, we tested the efficacy of releasing live insect hosts that were pre-infected with entomopathogenic nematodes against insect pests living in cryptic habitats. We hypothesized that the pre-infected hosts could carry the next generation of emerging nematode infective juveniles to hard-to-reach target sites, and thereby facilitate enhanced control in cryptic habitats. Thus, the infected hosts act as "living insect bombs" against the target pest. We tested this approach using two model insect pests: a chestnut tree pest, the goat moth Cossus cossus (Lepidiptera: Cossidae), and a lawn caterpillar, Spodoptera cilium (Lepidoptera: Noctuidae). One pest is considered hard-to-reach via aqueous spray (C. cossus) and the other is more openly exposed in the environment (S. cilium). C. cossus and S. cilium studies were conducted in chestnut logs and Bermudagrass arenas, respectively. The living bomb approach was compared with standard nematode application in aqueous spray and controls (without nematode application); Steinernema carpocapsae (Rize isolate) was used in all experiments. The percentage larval mortality of C. cossus was 86% in the living insect bomb treatment, whereas, all other treatments and controls exhibited less than 4% mortality. The new approach (living bomb) was equally successful as standard aqueous application for the control of S. cilium larvae. Both methods exhibited more than 90% mortality in the turfgrass arena. Our new approach showed an immense potential to control insect pests living in hard-to-reach cryptic habitats. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. PUMPS

    Science.gov (United States)

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  15. Analysis of event logs from syringe pumps: a retrospective pilot study to assess possible effects of syringe pumps on safety in a university hospital critical care unit in Germany.

    Science.gov (United States)

    Kastrup, Marc; Balzer, Felix; Volk, Thomas; Spies, Claudia

    2012-07-01

    Medication errors occur in approximately one out of five doses in a typical hospital setting. Patients in the intensive care unit (ICU) are particularly susceptible to errors during the application of intravenous drugs as they receive numerous potent drugs applied by syringe pumps. The aim of this study was to analyse the effects on potential harmful medication errors and to address factors that have potential for improving medication safety after the introduction of a standardized drug library into syringe pumps with integrated decision support systems. A team of physicians and nurses developed a dataset that defined standardized drug concentrations, application rates and alert limits to prevent accidental overdosing of intravenous medications. This dataset was implemented in 100 syringe pumps with the ability to log programming errors, alerts, reprogramming events and overrides ('smart pumps'). In this retrospective pilot study, all pump-related transaction data were obtained from the pump logs, by downloading the data from the pumps, covering 20 months of use between 1 April 2008 and 30 November 2009. Patient data were gathered from the electronic patient charts. The study was performed in a cardiothoracic ICU of the Charité University Hospital, Berlin, Germany. A total of 7884 patient treatment days and 133,601 infusion starts were evaluated. The drug library with the features of the dose rate was used in 92.8% of the syringe pump starts, in 1.5% of the starts a manual dosing mode without the use of the drug library was used and in 5.7% of the starts the mode 'mL/h', without any calculation features, was used. The most frequently used drugs were vasoactive drugs, followed by sedation medication. The user was alerted for a potentially harmful overdosing in 717 cases and in 66 cases the pumps were reprogrammed after the alert. During the early morning hours a higher rate of alarms was generated by the pumps, compared with the rest of the day. Syringe pumps with

  16. Evaluating release alternatives for a long-lived bird species under uncertainty about long-term demographic rates

    Science.gov (United States)

    Moore, Clinton T.; Converse, Sarah J.; Folk, Martin J.; Runge, Michael C.; Nesbitt, Stephen A.

    2012-01-01

    The release of animals to reestablish an extirpated population is a decision problem that is often attended by considerable uncertainty about the probability of success. Annual releases of captive-reared juvenile Whooping Cranes (Grus americana) were begun in 1993 in central Florida, USA, to establish a breeding, non-migratory population. Over a 12-year period, 286 birds were released, but by 2004, the introduced flock had produced only four wild-fledged birds. Consequently, releases were halted over managers' concerns about the performance of the released flock and uncertainty about the efficacy of further releases. We used data on marked, released birds to develop predictive models for addressing whether releases should be resumed, and if so, under what schedule. To examine the outcome of different release scenarios, we simulated the survival and productivity of individual female birds under a baseline model that recognized age and breeding-class structure and which incorporated empirically estimated stochastic elements. As data on wild-fledged birds from captive-reared parents were sparse, a key uncertainty that confronts release decision-making is whether captive-reared birds and their offspring share the same vital rates. Therefore, we used data on the only population of wild Whooping Cranes in existence to construct two alternatives to the baseline model. The probability of population persistence was highly sensitive to the choice of these three models. Under the baseline model, extirpation of the population was nearly certain under any scenario of resumed releases. In contrast, the model based on estimates from wild birds projected a high probability of persistence under any release scenario, including cessation of releases. Therefore, belief in either of these models suggests that further releases are an ineffective use of resources. In the third model, which simulated a population Allee effect, population persistence was sensitive to the release decision

  17. Pump characteristics and applications

    CERN Document Server

    Volk, Michael

    2013-01-01

    Providing a wealth of information on pumps and pump systems, Pump Characteristics and Applications, Third Edition details how pump equipment is selected, sized, operated, maintained, and repaired. The book identifies the key components of pumps and pump accessories, introduces the basics of pump and system hydraulics as well as more advanced hydraulic topics, and details various pump types, as well as special materials on seals, motors, variable frequency drives, and other pump-related subjects. It uses example problems throughout the text, reinforcing the practical application of the formulae

  18. On-line PWR RHR pump performance testing following motor and impeller replacement

    Energy Technology Data Exchange (ETDEWEB)

    DiMarzo, J.T.

    1996-12-01

    On-line maintenance and replacement of safety-related pumps requires the performance of an inservice test to determine and confirm the operational readiness of the pumps. In 1995, major maintenance was performed on two Pressurized Water Reactor (PWR) Residual Heat Removal (RHR) Pumps. A refurbished spare motor was overhauled with a new mechanical seal, new motor bearings and equipped with pump`s `B` impeller. The spare was installed into the `B` train. The motor had never been run in the system before. A pump performance test was developed to verify it`s operational readiness and determine the in-situ pump performance curve. Since the unit was operating, emphasis was placed on conducting a highly accurate pump performance test that would ensure that it satisfied the NSSS vendors accident analysis minimum acceptance curve. The design of the RHR System allowed testing of one train while the other was aligned for normal operation. A test flow path was established from the Refueling Water Storage Tank (RWST) through the pump (under test) and back to the RWST. This allowed staff to conduct a full flow range pump performance test. Each train was analyzed and an expression developed that included an error vector term for the TDH (ft), pressure (psig), and flow rate (gpm) using the variance error vector methodology. This method allowed the engineers to select a test instrumentation system that would yield accurate readings and minimal measurement errors, for data taken in the measurement of TDH (P,Q) versus Pump Flow Rate (Q). Test results for the `B` Train showed performance well in excess of the minimum required. The motor that was originally in the `B` train was similarly overhauled and equipped with `A` pump`s original impeller, re-installed in the `A` train, and tested. Analysis of the `A` train results indicate that the RHR pump`s performance was also well in excess of the vendors requirements.

  19. A Study on Optimal Wear Design for a Gerotor Pump

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Soon Man; Nam, Hyoung Chul; Lu, Lei; Shin, Joong Ho [Changwon National University, Changwon (Korea, Republic of)

    2009-01-15

    A disadvantage in the design of gerotor pump is a lack of parts that can be adjusted to compensate for wear in the rotor set, and as a consequence, it causes a sharp reduction of efficiency. In this paper, an attempt has been made to reduce the wear rate between the rotors of a gerotor pump. To do this, floating genetic algorithm (FGA) is used as an optimization technique for minimizing the wear rate proportional factor (WRPF). The result shows that the wear rate can be reduced considerably, e.g. approximately 8% in this paper, throughout the optimization using FGA.

  20. An improved resonantly driven piezoelectric gas pump

    International Nuclear Information System (INIS)

    Wu, Yue; Liu, Yong; Liu, Jianfang; Jiao, Xiaoyang; Yang, Zhigang; Wang, Long

    2013-01-01

    Piezoelectric pumps have the potential to be used in a variety of applications, such as in air circulation and compression. However, piezoelectric membrane pumps do not have enough driving capacity, and the heat induced during the direct contact between the driving part and the gas medium cannot be dissipated smoothly. When the gas is blocked, the piezoelectric vibrator generates heat quickly, which may eventually lead to damage. Resonantly driven piezoelectric stack pumps have high performance but no price advantage. In this situation, a novel, resonantly driven piezoelectric gas pump with annular bimorph as the driver is presented. In the study, the working principle of the novel pump was analyzed, the vibration mechanics model was determined, and the displacement amplified theory was studied. The outcome indicates that the displacement amplification factor is related with the original displacement provided by the piezoelectric bimorph. In addition, the displacement amplification effect is related to the stiffness of the spring lamination, adjustment spring, and piezoelectric vibrator, as well as to the systematic damping factor and the driving frequency. The experimental prototypes of the proposed pump were designed, and the displacement amplification effect and gas output performance were measured. At 70 V of sinusoidal AC driving voltage, the improved pump amplified the piezoelectric vibrator displacement by 4.2 times, the maximum gas output flow rate reached 1685 ml/min, and the temperature of the bimorph remained normal after 2000 hours of operation when the gas medium was blocked.

  1. Study on crack propagation of adhesively bonded DCB for aluminum foam using energy release rate

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Hye Jin; Lee, Sang Kyo; Cho, Chong Du [Inha University, Incheon (Korea, Republic of); Cho, Jae Ung [Kongju National University, Choenan (Korea, Republic of)

    2015-01-15

    Aluminum foam with initial crack, which has a closed cell form adhesively bonded, is studied to compare and analyze the crack propagation behavior by using both experimental and finite element analysis techniques. The specimen is loaded in Mode I type of fracture as 15 mm/min speed of a displacement control method. The experimental results were used to accommodate the finite element analysis performed with commercial software ABAQUS 6.10. First, using a video recording, five steps of experiment were selected at random and then the energy release rate was calculated. The estimated energy release rate was then used as fracture energy into the finite element analysis. Comparing the experimental axial load-displacement graphs and the finite element analysis results, roughly equivalent peak values were observed in the cohesive strength of the aluminum foam double cantilever beam. However, force versus displacement patterns showed somewhat different: little deformation was observed in aluminum foam, whereas adhesive parts in double cantilever beam were significantly deformed.

  2. Functional and biocompatibility performances of an integrated Maglev pump-oxygenator.

    Science.gov (United States)

    Zhang, Tao; Cheng, Guangming; Koert, Andrew; Zhang, Juntao; Gellman, Barry; Yankey, G Kwame; Satpute, Aditee; Dasse, Kurt A; Gilbert, Richard J; Griffith, Bartley P; Wu, Zhongjun J

    2009-01-01

    To provide respiratory support for patients with lung failure, a novel compact integrated pump-oxygenator is being developed. The functional and biocompatibility performances of this device are presented. The pump-oxygenator is designed by combining a magnetically levitated pump/rotor with a uniquely configured hollow fiber membrane bundle to create an assembly free, ultracompact, all-in-one system. The hemodynamics, gas transfer and biocompatibility performances of this novel device were investigated both in vitro in a circulatory flow loop and in vivo in an ovine animal model. The in vitro results showed that the device was able to pump blood flow from 2 to 8 L/min against a wide range of pressures and to deliver an oxygen transfer rate more than 300 mL/min at a blood flow of 6 L/min. Blood damage tests demonstrated low hemolysis (normalized index of hemolysis [NIH] approximately 0.04) at a flow rate of 5 L/min against a 100-mm Hg afterload. The data from five animal experiments (4 h to 7 days) demonstrated that the device could bring the venous blood to near fully oxygen-saturated condition (98.6% +/- 1.3%). The highest oxygen transfer rate reached 386 mL/min. The gas transfer performance was stable over the study duration for three 7-day animals. There was no indication of blood damage. The plasma free hemoglobin and platelet count were within the normal ranges. No gross thrombus is found on the explanted pump components and fiber surfaces. Both in vitro and in vivo results demonstrated that the newly developed pump-oxygenator can achieve sufficient blood flow and oxygen transfer with excellent biocompatibility.

  3. Pump element for a tube pump

    DEFF Research Database (Denmark)

    2011-01-01

    The invention relates to a tube pump comprising a tube and a pump element inserted in the tube, where the pump element comprises a rod element and a first and a second non-return valve member positioned a distance apart on the rod element. The valve members are oriented in the same direction...... relative to the rod element so as to allow for a fluid flow in the tube through the first valve member, along the rod element, and through the second valve member. The tube comprises an at least partly flexible tube portion between the valve members such that a repeated deformation of the flexible tube...... portion acts to alternately close and open the valve members thereby generating a fluid flow through the tube. The invention further relates to a pump element comprising at least two non-return valve members connected by a rod element, and for insertion in an at least partly flexible tube in such tube...

  4. Pumping behavior of sputtering ion pump

    Energy Technology Data Exchange (ETDEWEB)

    Chou, T.S.; Bittner, J.; Schuchman, J.

    1991-12-31

    To optimize the design of a distributed ion pump (DIP) for the Superconducting X-Ray Lithography Source (SXLS) the stability of the rotating electron cloud at very high magnetic field beyond transition, must be re-examined. In this work the pumping speed and frequency spectrum of a DIP at various voltages (1 to 10 KV) and various magnetic fields (0.1 to 4 Tesla) are measured. Three cell diameters 10 mm, 5 mm and 2.5 mm, each 8 mm long, and with 3 or 4 mm gaps between anode and cathode are investigated. In this study both the titanium cathodes and the stainless steel anode plates are perforated with holes comparable in size to the anode cell diameters. Only the partially saturated pumping behavior is under investigation. The ultimate pressure and conditioning of the pump will be investigated at a later date when the stability criterion for the electron cloud is better understood.

  5. Pumping behavior of sputtering ion pump

    Energy Technology Data Exchange (ETDEWEB)

    Chou, T.S.; Bittner, J.; Schuchman, J.

    1991-01-01

    To optimize the design of a distributed ion pump (DIP) for the Superconducting X-Ray Lithography Source (SXLS) the stability of the rotating electron cloud at very high magnetic field beyond transition, must be re-examined. In this work the pumping speed and frequency spectrum of a DIP at various voltages (1 to 10 KV) and various magnetic fields (0.1 to 4 Tesla) are measured. Three cell diameters 10 mm, 5 mm and 2.5 mm, each 8 mm long, and with 3 or 4 mm gaps between anode and cathode are investigated. In this study both the titanium cathodes and the stainless steel anode plates are perforated with holes comparable in size to the anode cell diameters. Only the partially saturated pumping behavior is under investigation. The ultimate pressure and conditioning of the pump will be investigated at a later date when the stability criterion for the electron cloud is better understood.

  6. Effect of firing conditions & release height on terminal performance of submunitions and conditions for optimum height of release

    Directory of Open Access Journals (Sweden)

    L.K. Gite

    2017-06-01

    Full Text Available Submunitions should exhibit optimum terminal performance at target end when released from certain pre-determined height. Selection of an optimum height of release of the submunitions depends on the terminal parameters like forward throw, remaining velocity, impact angle and flight time. In this paper, the effects of initial firing conditions and height of release on terminal performance of submunitions discussed in detail. For different height of release, the relation between range and forward throw is also established & validated for a number of firing altitude and rocket configurations.

  7. Feasibility studies for pump and treat technology at leaking underground storage tank sites in Michigan

    International Nuclear Information System (INIS)

    O'Brien, J.M.; Pekas, B.S.

    1993-01-01

    Releases from underground storage tanks have resulted in impacts to groundwater at thousands of sites across the US. Investigations of these sites were initiated on a national basis with the implementation of federal laws that became effective December 22, 1989 (40 CFR 280). Completion of these investigations has led to a wave of design and installation of pump and treat aquifer restoration systems where impacts to groundwater have been confirmed. The purpose of this paper is to provide managers with a demonstration of some of the techniques that can be used by the consulting industry in evaluating the feasibility of pump and treat systems. With knowledge of these tools, managers can better evaluate proposals for system design and their cost effectiveness. To evaluate the effectiveness of typical pump and treat systems for leaking underground storage tank (LUST) sites in Michigan, ten sites where remedial design had been completed were randomly chosen for review. From these ten, two sites were selected that represented the greatest contrast in the types of site conditions encountered. A release of gasoline at Site 1 resulted in contamination of groundwater and soil with benzene, toluene, ethylbenzene, and xylenes

  8. Multiple pump housing

    Science.gov (United States)

    Donoho, II, Michael R.; Elliott; Christopher M.

    2010-03-23

    A fluid delivery system includes a first pump having a first drive assembly, a second pump having a second drive assembly, and a pump housing. At least a portion of each of the first and second pumps are located in the housing.

  9. Enzimas miocárdicas na cirurgia de revascularização sem circulação extracorpórea Myocardial enzymes in off-pump CABG surgery

    Directory of Open Access Journals (Sweden)

    Paulo Roberto SOLTOSKI

    2000-06-01

    myocardial injury and its effect on outcome vs conventional CABG (on-pump remains unclear. MATERIAL AND METHODS: Retrospective study of 303 patients (122 off-pump, 181 on-pump after isolated CABG from Feb/97-Feb/99. CPK and EKG were obtained pre and post-op, MB fraction and troponin T levels were measured postoperatively. Complications were also recorded. The groups were comparable in terms of age (65 ± 10 vs 65 ± 9 yr, CCS and NYHA class. RESULTS: Mean number of grafts was 3.10 on-pump vs 2.26 off-pump. Perioperative myocardial infarction, morbidity and mortality (7/181 vs 6/122 were also comparable. There were higher postoperative CK levels in the on-pump group compared to the off-pump (548 ± 420 vs 236 ± 365. MB fraction was slightly higher in the on-pump group, but not significantly different (62 ± 197 vs 29 ± 46 nor was troponin T levels (3.5 ± 16 vs 3.5 ± 17 were An inverse correlation between the number of grafts and troponin T release in the off-pump group occurred early during our off-pump experience. There was no correlation between graft location and the incidence of infarcts or troponin T release. CONCLUSION: The higher troponin T release during our initial experience subsequently decreased. This suggests that improvements in operative technique (e.g. better exposure allowing more posterior grafts without surface trauma may be responsible. Current techniques make off-pump CABG a safe alternative for revascularization.

  10. Characteristics of electrostatic gas micro-pump with integrated polyimide passive valves

    International Nuclear Information System (INIS)

    Han, Jeahyeong; Yeom, Junghoon; Mensing, Glennys; Flachsbart, Bruce; Shannon, Mark A

    2012-01-01

    We report on the fabrication and characterization of electrostatic gas micro-pumps integrated with polyimide check valves. Touch-mode capacitance actuation, enabled by a fixed silicon electrode and a metal/polyimide diaphragm, creates the suction and push-out of the ambient gas; the gas flow is rectified by the check valves located at the inlet and outlet of the pump. The fabricated pumps were tested with various actuation voltages at different frequencies and duty cycles; an emphasis was placed on investigating the effect of valve flow conductance on the gas pumping characteristics. The pump with higher valve conductance could increase the operating frequency of the pump and affect the pumping characteristics from a pulsating flow to a continuous flow, leading to a higher gas flow rate. This electrostatic pump has a flow control resolution of 1 µL min −1 ; it could generate a gas flow up to 106 µL min −1 . (paper)

  11. Assessing the energy efficiency of pumps and pump units background and methodology

    CERN Document Server

    Bernd Stoffel, em Dr-Ing

    2015-01-01

    Assessing the Energy Efficiency of Pumps and Pump Units, developed in cooperation with Europump, is the first book available providing the background, methodology, and assessment tools for understanding and calculating energy efficiency for pumps and extended products (pumps+motors+drives). Responding to new EU requirements for pump efficiency, and US DOE exploratory work in setting pump energy efficiency guidelines, this book provides explanation, derivation, and illustration of PA and EPA methods for assessing energy efficiency. It surveys legislation related to pump energy eff

  12. Numerical Investigation of Transient Flow in a Prototype Centrifugal Pump during Startup Period

    Science.gov (United States)

    Zhang, Yu-Liang; Zhu, Zu-Chao; Dou, Hua-Shu; Cui, Bao-Ling; Li, Yi; Zhou, Zhao-Zhong

    2017-05-01

    Transient performance of pumps during transient operating periods, such as startup and stopping, has drawn more and more attentions recently due to the growing engineering needs. During the startup period of a pump, the performance parameters such as the flow rate and head would vary significantly in a broad range. Therefore, it is very difficult to accurately specify the unsteady boundary conditions for a pump alone to solve the transient flow in the absence of experimental results. The closed-loop pipe system including a centrifugal pump is built to accomplish the self-coupling calculation. The three-dimensional unsteady incompressible viscous flow inside the passage of the pump during startup period is numerically simulated using the dynamic mesh method. Simulation results show that there are tiny fluctuations in the flow rate even under stable operating conditions and this can be attributed to influence of the rotor-stator interaction. At the very beginning of the startup, the rising speed of the flow rate is lower than that of the rotational speed. It is also found that it is not suitable to predict the transient performance of pumps using the calculation method of quasi-steady flow, especially at the earlier period of the startup.

  13. Functional studies of sodium pump isoforms

    DEFF Research Database (Denmark)

    Clausen, Michael Jakob

    The Na+,K+-ATPase is an essential ion pump found in all animal cells. It uses the energy from ATP hydrolysis to export three Na+ and import two K+, both against their chemical gradients and for Na+ also against the electrical potential. Mammals require four Na+,K+-ATPase isoforms that each have...... unique expression profiles and specialized functional features. We use a Two Electrode Voltage Clamp setup to determine pre-steady-state and steady-state characteristics of each isoform and design chimeras to pin-point the structural elements responsible for observed differences. With this strategy we...

  14. Numerical modeling and design of a disk-type rotating permanent magnet induction pump

    Energy Technology Data Exchange (ETDEWEB)

    Koroteeva, E., E-mail: koroteeva@physics.msu.ru [Institute of Physics of University of Latvia, Salaspils 2169 (Latvia); Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Ščepanskis, M. [Laboratory for Mathematical Modelling of Environmental and Technological Processes, University of Latvia, Rīga 1002 (Latvia); Bucenieks, I.; Platacis, E. [Institute of Physics of University of Latvia, Salaspils 2169 (Latvia)

    2016-05-15

    Highlights: • The design and performance of a disk-type induction pump are described. • A 3D numerical model based on an iterative coupling between EM and hydrodynamic solvers is developed. • The model is verified by comparing with the experiments in a Pb-Bi loop facility. • The suggestions are given to estimate the pump performance in a Pb-Li loop at high pressures. - Abstract: Electromagnetic induction pumps with rotating permanent magnets appear to be the most promising devices to transport liquid metals in high-temperature applications. Here we present a numerical methodology to simulate the operation of one particular modification of these types of pumps: a disk-type induction pump. The numerical model allows for the calculation and analysis of the flow parameters, including the pressure–flow rate characteristics of the pump. The simulations are based on an iterative fully coupled scheme for electromagnetic and hydrodynamic solvers. The developed model is verified by comparing with experimental data obtained using a Pb-Bi loop test facility, for pressures up to 4 bar and flow rates up to 9 kg/s. The verified model is then expanded to higher pressures, beyond the limits of the experimental loop. Based on the numerical simulations, suggestions are given to extrapolate experimental data to higher (industrially important) pressure ranges. Using the numerical model and analytical estimation, the pump performance for the Pb-Li loop is also examined, and the ability of the designed pump to develop pressure heads over 6 bar and to provide flow rates over 15 kg/s is shown.

  15. Organizational and technological correlates of nurses' trust in a smart intravenous pump.

    Science.gov (United States)

    Montague, Enid; Asan, Onur; Chiou, Erin

    2013-03-01

    The aim of this study was to understand technology and system characteristics that contribute to nurses' ratings of trust in a smart intravenous pump. Nurses' trust in new technologies can influence how technologies are used. Trust in technology is defined as a person's belief that a technology will not fail them. Potential outcomes of trust in technology are appropriate trust, overtrust, distrust, and mistrust. Trust in technology is also related to several use-specific outcomes, including appropriate use and inappropriate use such as overreliance, disuse or rejection, or misuse. Understanding trust in relation to outcomes can contribute to designs that facilitate appropriate trust in new technologies. A survey was completed by 391 nurses a year after the implementation of a new smart intravenous pump. The survey assessed trust in the intravenous pump and other elements of the sociotechnical system, individual characteristics, technology characteristics, and organizational characteristics. Results show that perceptions of usefulness, safety, ease of use, and usability are related to ratings of trust in smart intravenous pumps. Other work systemfactors such as perception of work environment, age, experience, quality of work, and perception of work performance are also related to ratings of trust. Nurses' trust in smart intravenous pumps is influenced by both characteristics of the technology and the sociotechnical system. Findings from this research have implications for the design of future smart intravenous pumps and health systems. Recommendations for appropriately trustworthy smart intravenous pumps are discussed. Findings also have implications for how trust in health technologies can be measured and conceptualized in complex sociotechnical systems.

  16. Air-lift pumps characteristics under two-phase flow conditions

    International Nuclear Information System (INIS)

    Kassab, Sadek Z.; Kandil, Hamdy A.; Warda, Hassan A.; Ahmed, Wael H.

    2009-01-01

    Air-lift pumps are finding increasing use where pump reliability and low maintenance are required, where corrosive, abrasive, or radioactive fluids in nuclear applications must be handled and when a compressed air is readily available as a source of a renewable energy for water pumping applications. The objective of the present study is to evaluate the performance of a pump under predetermined operating conditions and to optimize the related parameters. For this purpose, an air-lift pump was designed and tested. Experiments were performed for nine submergence ratios, and three risers of different lengths with different air injection pressures. Moreover, the pump was tested under different two-phase flow patterns. A theoretical model is proposed in this study taking into account the flow patterns at the best efficiency range where the pump is operated. The present results showed that the pump capacity and efficiency are functions of the air mass flow rate, submergence ratio, and riser pipe length. The best efficiency range of the air-lift pumps operation was found to be in the slug and slug-churn flow regimes. The proposed model has been compared with experimental data and the most cited models available. The proposed model is in good agreement with experimental results and found to predict the liquid volumetric flux for different flow patterns including bubbly, slug and churn flow patterns

  17. Design and analysis of hydraulic ram water pumping system

    Science.gov (United States)

    Hussin, N. S. M.; Gamil, S. A.; Amin, N. A. M.; Safar, M. J. A.; Majid, M. S. A.; Kazim, M. N. F. M.; Nasir, N. F. M.

    2017-10-01

    The current pumping system (DC water pump) for agriculture is powered by household electricity, therefore, the cost of electricity will be increased due to the higher electricity consumption. In addition, the water needs to be supplied at different height of trees and different places that are far from the water source. The existing DC water pump can pump the water to 1.5 m height but it cost money for electrical source. The hydraulic ram is a mechanical water pump that suitable used for agriculture purpose. It can be a good substitute for DC water pump in agriculture use. The hydraulic ram water pumping system has ability to pump water using gravitational energy or the kinetic energy through flowing source of water. This project aims to analyze and develop the water ram pump in order to meet the desired delivery head up to 3 meter height with less operation cost. The hydraulic ram is designed using CATIA software. Simulation work has been done using ANSYS CFX software to validate the working concept. There are three design were tested in the experiment study. The best design reached target head of 3 m with 15% efficiency and flow rate of 11.82l/min. The results from this study show that the less diameter of pressure chamber and higher supply head will create higher pressure.

  18. WATER HYACINTH: A POSSIBLE ALTERNATIVE RATE RETARDING NATURAL POLYMER USED IN SUSTAINED RELEASE TABLET DESIGN

    Directory of Open Access Journals (Sweden)

    Sabera eKhatun

    2014-06-01

    Full Text Available In recent years natural polymers have been widely used, because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5%, 10%, 15%, 20%, 25% and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carr’s Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR, Differential Scanning Calorimetry (DSC and Scanning Electron Microscopy (SEM studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37oC ± 0.5 temperature, for 8 hours. All the formulations comply with both BP and USP requirements, but among all the formulations F-1 (5% of Water hyacinth was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations.

  19. Water hyacinth: a possible alternative rate retarding natural polymer used in sustained release tablet design.

    Science.gov (United States)

    Khatun, Sabera; Sutradhar, Kumar B

    2014-01-01

    In recent years natural polymers have been widely used because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5, 10, 15, 20, 25 and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carr's Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37°C ± 0.5 temperature for 8 h. Though all the formulations comply with both BP and USP requirements, formulation F-1 (5% of Water hyacinth) was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell, and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations.

  20. Glycine receptors support excitatory neurotransmitter release in developing mouse visual cortex

    Science.gov (United States)

    Kunz, Portia A; Burette, Alain C; Weinberg, Richard J; Philpot, Benjamin D

    2012-01-01

    Glycine receptors (GlyRs) are found in most areas of the brain, and their dysfunction can cause severe neurological disorders. While traditionally thought of as inhibitory receptors, presynaptic-acting GlyRs (preGlyRs) can also facilitate glutamate release under certain circumstances, although the underlying molecular mechanisms are unknown. In the current study, we sought to better understand the role of GlyRs in the facilitation of excitatory neurotransmitter release in mouse visual cortex. Using whole-cell recordings, we found that preGlyRs facilitate glutamate release in developing, but not adult, visual cortex. The glycinergic enhancement of neurotransmitter release in early development depends on the high intracellular to extracellular Cl− gradient maintained by the Na+–K+–2Cl− cotransporter and requires Ca2+ entry through voltage-gated Ca2+ channels. The glycine transporter 1, localized to glial cells, regulates extracellular glycine concentration and the activation of these preGlyRs. Our findings demonstrate a developmentally regulated mechanism for controlling excitatory neurotransmitter release in the neocortex. PMID:22988142

  1. Optimal hydraulic design of new-type shaft tubular pumping system

    International Nuclear Information System (INIS)

    Zhu, H G; Zhang, R T; Zhou, J R

    2012-01-01

    Based on the characteristics of large flow rate, low-head, short annual operation time and high reliability of city flood-control pumping stations, a new-type shaft tubular pumping system featuring shaft suction box, siphon-type discharge passage with vacuum breaker as cutoff device was put forward, which possesses such advantages as simpler structure, reliable cutoff and higher energy performance. According to the design parameters of a city flood control pumping station, a numerical computation model was set up including shaft-type suction box, siphon-type discharge passage, pump impeller and guide vanes. By using commercial CFD software Fluent, RNG κ-ε turbulence model was adopted to close the three-dimensional time-averaged incompressible N-S equations. After completing optimal hydraulic design of shaft-type suction box, and keeping the parameters of total length, maximum width and outlet section unchanged, siphon-type discharge passages of three hump locations and three hump heights were designed and numerical analysis on the 9 hydraulic design schemes of pumping system were proceeded. The computational results show that the changing of hump locations and hump heights directly affects the internal flow patterns of discharge passages and hydraulic performances of the system, and when hump is located 3.66D from the inlet section and hump height is about 0.65D (D is the diameter of pump impeller), the new-type shaft tubular pumping system achieves better energy performances. A pumping system model test of the optimal designed scheme was carried out. The result shows that the highest pumping system efficiency reaches 75.96%, and when at design head of 1.15m the flow rate and system efficiency were 0.304m 3 /s and 63.10%, respectively. Thus, the validity of optimal design method was verified by the model test, and a solid foundation was laid for the application and extension of the new-type shaft tubular pumping system.

  2. Performance prediction method for a multi-stage Knudsen pump

    Science.gov (United States)

    Kugimoto, K.; Hirota, Y.; Kizaki, Y.; Yamaguchi, H.; Niimi, T.

    2017-12-01

    In this study, the novel method to predict the performance of a multi-stage Knudsen pump is proposed. The performance prediction method is carried out in two steps numerically with the assistance of a simple experimental result. In the first step, the performance of a single-stage Knudsen pump was measured experimentally under various pressure conditions, and the relationship of the mass flow rate was obtained with respect to the average pressure between the inlet and outlet of the pump and the pressure difference between them. In the second step, the performance of a multi-stage pump was analyzed by a one-dimensional model derived from the mass conservation law. The performances predicted by the 1D-model of 1-stage, 2-stage, 3-stage, and 4-stage pumps were validated by the experimental results for the corresponding number of stages. It was concluded that the proposed prediction method works properly.

  3. Thermodynamic analysis of a thermally operated cascade sorption heat pump for continuous cold generation

    Energy Technology Data Exchange (ETDEWEB)

    Muthukumar, P.; Lakshmi, D.V.N. [Department of Mechanical Engineering, Indian Institute of Technology, Guwahati – 781039 (India)

    2013-07-01

    In this paper, the thermodynamic analysis of a cascade sorption system consists of a two-stage metal hydride heat pump as topping cycle and a single-stage lithium bromide water system as bottom cycle is presented. The effects of various operating temperatures such as driving heat, heat release and refrigeration temperatures, and design parameters such as ratio of metal hydride mass to reactor mass and sensible heat exchange factor on the combined coefficient of performance (COP) of the cascade cycle, and specific cooling power (SCP) and total cold output of the metal hydride heat pump cycle are presented. It is observed that the combined COP is found to increase with heat release and refrigeration temperatures and however, decreases with driving heat temperature. Increase of sensible heat exchange factor improves the system performances significantly. Reduction in mass ratio from 0.5 to 0.1 improves the combined COP of the cascade system by about 10 %. The maximum predicted combined COP of the system is about 1.66 at the driving heat, heat release and refrigeration temperatures of 270 deg C, 125 deg C and 12deg C, respectively.

  4. Performance Analysis Of Single-Pumped And Dual-Pumped Parametric Optical Amplifier

    Directory of Open Access Journals (Sweden)

    Sandar Myint

    2015-06-01

    Full Text Available Abstract In this study we present a performance analysis of single-pumped and dual- pumped parametric optical amplifier and present the analysis of gain flatness in dual- pumped Fiber Optical Parametric Amplifier FOPA based on four-wave mixing FWM. Result shows that changing the signal power and pump power give the various gains in FOPA. It is also found out that the parametric gain increase with increase in pump power and decrease in signal power. .Moreover in this paper the phase matching condition in FWM plays a vital role in predicting the gain profile of the FOPAbecause the parametric gain is maximum when the total phase mismatch is zero.In this paper single-pumped parametric amplification over a 50nm gain bandwidth is demonstrated using 500 nm highly nonlinear fiber HNLF and signal achieves about 31dB gain. For dual-pumped parametric amplification signal achieves 26.5dB gains over a 50nm gain bandwidth. Therefore dual-pumped parametric amplifier can provide relatively flat gain over a much wider bandwidth than the single-pumped FOPA.

  5. A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Erren Yao

    2013-03-01

    Full Text Available A novel pumped hydro combined with compressed air energy storage (PHCA system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented. This paper discovers how such parameters affect the performance of the whole system. The ideal performance of this novel system has the following advantages: a simple, highly effective and low cost structure, which is comparable to the efficiency of a traditional pumped hydro storage system. Research results show a great solution to the current storage constraints encountered in the development of the wind power industry in China, which have been widely recognised as a bottleneck in the wind energy storage industry.

  6. A sophisticated programmable miniaturised pump for insulin delivery.

    Science.gov (United States)

    Klein, J C; Slama, G

    1980-09-01

    We have conceived a truly pre-programmable infusion system usable for intravenous administration of insulin in diabetic subjects. The original system has been built into a small, commercially available, syringe-pump of which only the case and the mechanical parts have been kept. The computing until has a timer, a programmable memory of 512 words by 8 bits and a digital-to-frequency converter to run the motor which drives the syringe. The memory contains 8 profiles of insulin injections stored in digital form over 64 words. Each profile is selected by the patient before eating according to the carbohydrate content of the planned meal and last about two hours, starting from and returning to the basal rate of insulin, at which it remains until next profile selection. Amount, profiles and duration of insulin injection are either mean values deduced from previous studies with a closed-loop artificial pancreas or personally fitted values; they are stored in an instantly replaceable memory cell. This device allows the patient to choose the time, nature and amount of his food intake.

  7. Residual heat removal pump and low pressure safety injection pump retrofit program

    International Nuclear Information System (INIS)

    Dudiak, J.G.; McKenna, J.M.

    1992-01-01

    Residual Heat Removal (RHR) and low pressure safety injection (LPSI) pumps installed in pressurized water-to-reactor power plants are used to provide low-head safety injection in the event of loss of coolant in the reactor coolant system. Because these pumps are subjected to rather severe temperature and pressure transients, the majority of pumps installed in the RHR service are vertical pumps with a single stage impeller. Typically the pump impeller is mounted on an extended motor shaft (close-coupled configuration) and a mechanical seal is employed at the pump end of the shaft. Traditionally RHR and LPSI pumps have been a significant maintenance item for many utilities. Periodic mechanical seal of motor bearing replacement often is considered routine maintenance. The closed-coupled pump design requires disassembly of the casing cover from the lower pump casing while performing these routine maintenance tasks. This paper introduces a design modification developed to convert the close-coupled RHR and LPSI pumps to a coupled configuration

  8. Na+-K+ pump in chronic renal failure

    International Nuclear Information System (INIS)

    Deepak, K.; Kahn, T.

    1987-01-01

    This review summarizes the evidence for the defect in Na + -K + pump in chronic renal failure, considers the role of various factors in causing this defect, and discusses the clinical implications thereof. Intracellular Na is elevated in erythrocytes, leukocytes, and muscle cells from some patients with chronic renal failure (CRF). Recent evidence suggest that this elevation of cell Na may be, in large part, a consequence of decreased number of Na + -K + pump units per cell. Maintenance dialysis over a period of weeks ameliorates the defect in intracellular Na + , and this improvement is contemporaneous with an increase in the number of Na + -K + pump sites per cell. In erythrocytes with normal cell Na + , acute hemodialysis increases the rate of 22 Na + and 42 K + transport. Many factors such as the presence of retained toxic metabolite or circulating inhibitor in the uremic plasma, or biochemical changes produced by acute hemodialysis, may explain this finding. In cells with high cell Na + , the pump-mediated 42 K + transport is normalized at the expense of a raised cell Na + . The decreased muscle membrane potential in uremic subjects has been attributed to a decreased activity of Na + -K + pump. The authors discuss the role of hormonal abnormalities and circulating inhibitors, which may cause an acute inhibition of the pump and of other factors such as K + depletion, which may cause more chronic alterations. The implications of alteration of Na + and K + pump transport and raised cell Na + on other non-pump-mediated transport pathways are discussed. Raised cell Na + may be a marker for the adequacy of maintenance dialysis in patients with end-stage renal failure

  9. Maximum permissible continuous release rates of phosphorus-32 and sulphur-35 to atmosphere in a milk producing area

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, P M

    1963-01-01

    A method is given for calculating, for design purposes, the maximum permissible continuous release rates of phosphorus-32 and sulphur-35 to atmosphere with respect to milk contamination. In the absence of authoritative advice from the Medical Research Council, provisional working levels for the concentration of phosphorus-32 and sulphur-35 in milk are derived, and details are given of the agricultural assumptions involved in the calculation of the relationship between the amount of the nuclide deposited on grassland and that to be found in milk. The agricultural and meteorological conditions assumed are applicable as an annual average to England and Wales. The results (in mc/day) for phosphorus-32 and sulphur-35 for a number of stack heights and distances are shown graphically; typical values, quoted in a table, include 20 mc/day of phosphorus-32 and 30 mc/day of sulfur-35 as the maximum permissible continuous release rates with respect to ground level releases at a distance of 200 metres from pastureland.

  10. Seven-laser diode end-pumped Nd

    International Nuclear Information System (INIS)

    Berger, J.; Welch, D.F.; Streifer, W.; Scifres, D.R.; Smith, J.J.; Hoffman, H.J.; Peisley, D.; Radecki, D.

    1988-01-01

    End pumping of solid-state lasers by single semiconductor laser diode arrays (LDAs) is efficient, but the maximum pump power is limited by the source brightness and matching the TEM/sub 00/ Nd:YAG cavity mode. To increase the output power from a solid-state Nd:YAG laser, one option is to employ a multiplicity of LDA to provide more pump power than is available from a single source. The authors report herein a 660-mW cw TEM/sub 00/ Nd:YAG laser, end-pumped by seven LDA, with bundled optical fibers coupling the light from each diode to the Nd:YAG rod end. The maximum electrical-to-optical conversion efficiency attained was 4.7% at 560-mW Nd:YAG output power. The LDAs (SDL-2430-C, 100 μm wide) were mounted on separate thermoelectric coolers to tune emission wavelength to the Nd:YAG absorption bands. The diodes were operated at their rated output power (50,000 h mean time to failure). The 110/125-μm diam 0.37-N.A. fibers were butt coupled to the lasers and glued together into a hexagonal close pack. The authors have obtained the highest average power demonstrated to date in the TEM/sub 00/ mode from a Nd:YAG laser, reliably end-pumped by multiple laser diodes with good efficiency

  11. Pump Application as Hydraulic Turbine – Pump as Turbine (PaT)

    OpenAIRE

    Rusovs, D

    2009-01-01

    The paper considers pump operation as hydraulic turbine with purpose to produce mechanical power from liquid flow. The Francis hydraulic turbine was selected for comparison with centrifugal pump in reverse operation. Turbine and centrifugal pump velocity triangles were considered with purpose to evaluate PaT efficiency. Shape of impeller blades for turbine and pumps was analysed. Specific speed calculation is carried out with purpose to obtain similarity in pump and turbine description. For ...

  12. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2014-04-01

    A single Na(+)/K(+)-ATPase pumps three Na(+) outwards and two K(+) inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na(+) than K(+) generates outward current across the cell membrane. Less well understood is the ability of Na(+)/K(+) pumps to generate an inward current of protons. Originally noted in pumps deprived of external K(+) and Na(+) ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K(+) and Na(+) concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na(+) release from phosphorylated Na(+)/K(+) pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na(+)/K(+) pumps that enables proton import is not required for completion of the 3 Na(+)/2 K(+) transport cycle. However, the back-step occurs readily during Na(+)/K(+) transport when external K(+) ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na(+)-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na(+) and K(+) ions that passes through binding site II. The inferred occurrence of Na(+)/K(+) exchange and H(+) import during the same conformational cycle of a single molecule identifies the Na(+)/K(+) pump as a hybrid transporter. Whether Na(+)/K(+) pump-mediated proton inflow may have any physiological or

  13. Quantifying the energy required for groundwater pumping across a regional aquifer system

    Science.gov (United States)

    Ronayne, M. J.; Shugert, D. T.

    2017-12-01

    Groundwater pumping can be a substantial source of energy expenditure, particularly in semiarid regions with large depths to water. In this study we assessed the energy required for groundwater pumping in the Denver Basin aquifer system, a group of sedimentary rock aquifers used for municipal water supply in Colorado. In recent decades, declining water levels in the Denver Basin aquifers has resulted in increased pumping lifts and higher energy use rates. We quantified the spatially variable energy intensity for groundwater pumping by analyzing spatial variations in the lift requirement. The median energy intensities for two major aquifers were 1.2 and 1.8 kWh m-3. Considering typical municipal well production rates and household water use in the study area, these results indicate that the energy cost associated with groundwater pumping can be a significant fraction (>20%) of the total electricity consumption for all household end uses. Pumping at this scale (hundreds of municipal wells producing from deep aquifers) also generates substantial greenhouse gas emissions. Analytical wellfield modeling conducted as part of this study clearly demonstrates how multiple components of the lift impact the energy requirement. Results provide guidance for water management strategies that reduce energy expenditure.

  14. Novel regulation of cardiac Na pump via phospholemman.

    Science.gov (United States)

    Pavlovic, Davor; Fuller, William; Shattock, Michael J

    2013-08-01

    As the only quantitatively significant Na efflux pathway from cardiac cells, the Na/K ATPase (Na pump) is the primary regulator of intracellular Na. The transmembrane Na gradient it establishes is essential for normal electrical excitability, numerous coupled-transport processes and, as the driving force for Na/Ca exchange, thus setting cardiac Ca load and contractility. As Na influx varies with electrical excitation, heart rate and pathology, the dynamic regulation of Na efflux is essential. It is now widely recognized that phospholemman, a 72 amino acid accessory protein which forms part of the Na pump complex, is the key nexus linking cellular signaling to pump regulation. Phospholemman is the target of a variety of post-translational modifications (including phosphorylation, palmitoylation and glutathionation) and these can dynamically alter the activity of the Na pump. This review summarizes our current understanding of the multiple regulatory mechanisms that converge on phospholemman and govern NA pump activity in the heart. The corrected Fig. 4 is reproduced below. The publisher would like to apologize for any inconvenience caused. [corrected]. Copyright © 2013. Published by Elsevier Ltd.

  15. An implantable centrifugal blood pump with a recirculating purge system (Cool-Seal system).

    Science.gov (United States)

    Yamazaki, K; Litwak, P; Tagusari, O; Mori, T; Kono, K; Kameneva, M; Watach, M; Gordon, L; Miyagishima, M; Tomioka, J; Umezu, M; Outa, E; Antaki, J F; Kormos, R L; Koyanagi, H; Griffith, B P

    1998-06-01

    A compact centrifugal blood pump has been developed as an implantable left ventricular assist system. The impeller diameter is 40 mm, and pump dimensions are 55 x 64 mm. This first prototype, fabricated from titanium alloy, resulted in a pump weight of 400 g including a brushless DC motor. The weight of a second prototype pump was reduced to 280 g. The entire blood contacting surface is coated with diamond like carbon (DLC) to improve blood compatibility. Flow rates of over 7 L/min against 100 mm Hg pressure at 2,500 rpm with 9 W total power consumption have been measured. A newly designed mechanical seal with a recirculating purge system (Cool-Seal) is used for the shaft seal. In this seal system, the seal temperature is kept under 40 degrees C to prevent heat denaturation of blood proteins. Purge fluid also cools the pump motor coil and journal bearing. Purge fluid is continuously purified and sterilized by an ultrafiltration unit which is incorporated in the paracorporeal drive console. In vitro experiments with bovine blood demonstrated an acceptably low hemolysis rate (normalized index of hemolysis = 0.005 +/- 0.002 g/100 L). In vivo experiments are currently ongoing using calves. Via left thoracotomy, left ventricular (LV) apex descending aorta bypass was performed utilizing an expanded polytetrafluoroethylene (ePTFE) vascular graft with the pump placed in the left thoracic cavity. In 2 in vivo experiments, the pump flow rate was maintained at 5-9 L/min, and pump power consumption remained stable at 9-10 W. All plasma free Hb levels were measured at less than 15 mg/dl. The seal system has demonstrated good seal capability with negligible purge fluid consumption (<0.5 ml/day). In both calves, the pumps demonstrated trouble free continuous function over 6 month (200 days and 222 days).

  16. [A Quantitative Verification for Operability of Three PCA Devices Attached to the Disposable Infusion Pumps].

    Science.gov (United States)

    Tadokoro, Takahiro; Fuchibe, Makoto; Odo, Yuichiro; Kakinohana, Manabu

    2015-11-01

    In this study using 3 different PCA devices (Baxter infuser LVBB +PCM 2 ml: Pump B, Coopdech Balloonjector +PCA 3 ml: Pump C, Rakuraku fuser +PCA 3 ml: Pump S), we investigated how easily PCA devices could be handled. In this study with 42 volunteers (14 elders and 28 nurses), we compared 3 PCA ejection volume and ejection rate among three PCA devices. PCA ejection rate was defined as the ratio of actual ejection volume to the maximum ejection volume (MEV) of each PCA device. Although not only elders but also nurses failed to produce accurate PCA ejection volume in the Pump B, Pump S could provide the MEV even by elders. In the Pump C, approximately 80% of MEV could be achieved by nurses, but 60% of MEV by elders (P PCA ejection volume might be dependent on PCA device.

  17. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  18. Pre-operational proof and leakage rate testing requirements for concrete containment structures for CANDU nuclear power plants

    International Nuclear Information System (INIS)

    1994-02-01

    This Standard provides the requirements for pre-operational proof tests and leakage rate tests of concrete containment structures of a containment system designed as Class Containment components. 1 fig

  19. An acoustic method for characterizing the onset of cavitation in nozzles and pumps

    International Nuclear Information System (INIS)

    Courbiere, P.

    1984-12-01

    The high sodium flow rates required by the reactor power rating have led to the use of sodium loop and pump designs in which a cavitation hazard exists. This paper discusses CEA test results on incipient cavitation, and examines pump impeller scale effects, sodium-water similitude criteria and the influence of the entrained gas content in the sodium flow

  20. On the effect of hyperaldosteronism-inducing mutations in Na/K pumps.

    Science.gov (United States)

    Meyer, Dylan J; Gatto, Craig; Artigas, Pablo

    2017-11-06

    Primary aldosteronism, a condition in which too much aldosterone is produced and that leads to hypertension, is often initiated by an aldosterone-producing adenoma within the zona glomerulosa of the adrenal cortex. Somatic mutations of ATP1A1, encoding the Na/K pump α1 subunit, have been found in these adenomas. It has been proposed that a passive inward current transported by several of these mutant pumps is a "gain-of-function" activity that produces membrane depolarization and concomitant increases in aldosterone production. Here, we investigate whether the inward current through mutant Na/K pumps is large enough to induce depolarization of the cells that harbor them. We first investigate inward currents induced by these mutations in Xenopus Na/K pumps expressed in Xenopus oocytes and find that these inward currents are similar in amplitude to wild-type outward Na/K pump currents. Subsequently, we perform a detailed functional evaluation of the human Na/K pump mutants L104R, delF100-L104, V332G, and EETA963S expressed in Xenopus oocytes. By combining two-electrode voltage clamp with [ 3 H]ouabain binding, we measure the turnover rate of these inward currents and compare it to the turnover rate for outward current through wild-type pumps. We find that the turnover rate of the inward current through two of these mutants (EETA963S and L104R) is too small to induce significant cell depolarization. Electrophysiological characterization of another hyperaldosteronism-inducing mutation, G99R, reveals the absence of inward currents under many different conditions, including in the presence of the regulator FXYD1 as well as with mammalian ionic concentrations and body temperatures. Instead, we observe robust outward currents, but with significantly reduced affinities for intracellular Na + and extracellular K + Collectively, our results point to loss-of-function as the common mechanism for the hyperaldosteronism induced by these Na/K pump mutants. © 2017 Meyer et al.

  1. Comparison of infusion pumps calibration methods

    Science.gov (United States)

    Batista, Elsa; Godinho, Isabel; do Céu Ferreira, Maria; Furtado, Andreia; Lucas, Peter; Silva, Claudia

    2017-12-01

    Nowadays, several types of infusion pump are commonly used for drug delivery, such as syringe pumps and peristaltic pumps. These instruments present different measuring features and capacities according to their use and therapeutic application. In order to ensure the metrological traceability of these flow and volume measuring equipment, it is necessary to use suitable calibration methods and standards. Two different calibration methods can be used to determine the flow error of infusion pumps. One is the gravimetric method, considered as a primary method, commonly used by National Metrology Institutes. The other calibration method, a secondary method, relies on an infusion device analyser (IDA) and is typically used by hospital maintenance offices. The suitability of the IDA calibration method was assessed by testing several infusion instruments at different flow rates using the gravimetric method. In addition, a measurement comparison between Portuguese Accredited Laboratories and hospital maintenance offices was performed under the coordination of the Portuguese Institute for Quality, the National Metrology Institute. The obtained results were directly related to the used calibration method and are presented in this paper. This work has been developed in the framework of the EURAMET projects EMRP MeDD and EMPIR 15SIP03.

  2. Involvement of Na,K-pump in SEPYLRFamide-mediated reduction of cholinosensitivity in Helix neurons.

    Science.gov (United States)

    Pivovarov, Arkady S; Foreman, Richard C; Walker, Robert J

    2007-02-01

    SEPYLRFamide acts as an inhibitory modulator of acetylcholine (ACh) receptors in Helix lucorum neurones. Ouabain, a specific inhibitor of Na,K-pump, (0.1 mM, bath application) decreased the ACh-induced inward current (ACh-current) and increased the leak current. Ouabain decreased the modulatory SEPYLRFamide effect on the ACh-current. There was a correlation between the effects of ouabain on the amplitude of the ACh-cu