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

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

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

Multidrug efflux pumps at the crossroad between antibiotic resistance and bacterial virulence

Directory of Open Access Journals (Sweden)

Manuel Alcalde-Rico

2016-09-01

Full Text Available Multidrug efflux pumps can be involved in bacterial resistance to antibiotics at different levels. Some efflux pumps are constitutively expressed at low levels and contribute to intrinsic resistance. In addition, their overexpression may allow higher levels of resistance. This overexpression can be transient, in the presence of an effector (phenotypic resistance, or constitutive when mutants in the regulatory elements of the expression of efflux pumps are selected (acquired resistance. Efflux pumps are present in all cells, from human to bacteria and are highly conserved, which indicates that they are ancient elements in the evolution of different organisms. Consequently, it has been suggested that, besides antibiotic resistance, bacterial multidrug efflux pumps would likely contribute to other relevant process of the microbial physiology. In the current article, we discuss some specific examples of the role that efflux pumps may have in the bacterial virulence of animals' and plants' pathogens, including the processes of intercellular communication. Based in these evidences, we propose that efflux pumps are at the crossroad between resistance and virulence of bacterial pathogens. Consequently, the comprehensive study of multidrug efflux pumps requires addressing these functions, which are of relevance for the bacterial-host interactions during infection.

Multidrug Efflux Pumps at the Crossroad between Antibiotic Resistance and Bacterial Virulence.

Science.gov (United States)

Alcalde-Rico, Manuel; Hernando-Amado, Sara; Blanco, Paula; Martínez, José L

2016-01-01

Multidrug efflux pumps can be involved in bacterial resistance to antibiotics at different levels. Some efflux pumps are constitutively expressed at low levels and contribute to intrinsic resistance. In addition, their overexpression may allow higher levels of resistance. This overexpression can be transient, in the presence of an effector (phenotypic resistance), or constitutive when mutants in the regulatory elements of the expression of efflux pumps are selected (acquired resistance). Efflux pumps are present in all cells, from human to bacteria and are highly conserved, which indicates that they are ancient elements in the evolution of different organisms. Consequently, it has been suggested that, besides antibiotic resistance, bacterial multidrug efflux pumps would likely contribute to other relevant processes of the microbial physiology. In the current article, we discuss some specific examples of the role that efflux pumps may have in the bacterial virulence of animals' and plants' pathogens, including the processes of intercellular communication. Based in these evidences, we propose that efflux pumps are at the crossroad between resistance and virulence of bacterial pathogens. Consequently, the comprehensive study of multidrug efflux pumps requires addressing these functions, which are of relevance for the bacterial-host interactions during infection.

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+.

Experimental investigation of saturation effect on pump-to-signal intensity modulation transfer in single-pump phase-insensitive fiber optic parametric amplifiers

DEFF Research Database (Denmark)

Cristofori, Valentina; Lali-Dastjerdi, Zohreh; Lund-Hansen, Toke

2013-01-01

We present an experimental characterization of how signal gain saturation affects the transfer of intensity modulation from the pump to the signal in single-pump, phase-insensitive fiber optic parametric amplifiers (FOPAs). In this work, we demonstrate experimentally for the first time, to our...... knowledge, how gain saturation of a FOPA reduces the noise contribution due to the transfer of pump power fluctuations to the signal. In a particular example, it is shown that the transferred noise is significantly reduced by a factor of 3, while the FOPA gain remains above 10 dB....

Pumping of magnons in a Dzyaloshinskii-Moriya ferromagnet

Science.gov (United States)

Kovalev, Alexey A.; Zyuzin, Vladimir A.; Li, Bo

2017-04-01

We formulate a microscopic linear response theory of magnon pumping applicable to multiple-magnonic-band uniform ferromagnets with Dzyaloshinskii-Moriya interactions. From the linear response theory, we identify the extrinsic and intrinsic contributions where the latter is expressed via the Berry curvature of magnonic bands. We observe that in the presence of a time-dependent magnetization Dzyaloshinskii-Moriya interactions can act as fictitious electric fields acting on magnons. We study various current responses to this fictitious field and analyze the role of Berry curvature. In particular, we obtain an analog of the Hall-like response in systems with nontrivial Berry curvature of magnon bands. After identifying the magnon-mediated contribution to the equilibrium Dzyaloshinskii-Moriya interaction, we also establish the Onsager reciprocity between the magnon mediated thermal torques and heat pumping. We apply our theory to the magnonic heat pumping and torque responses in honeycomb and kagome lattice ferromagnets.

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

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

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

Energy efficient ammonia heat pump. Final report

Energy Technology Data Exchange (ETDEWEB)

Madsen, Claus; Pijnenburg, B.; Schumann Grindorf, H. [Danish Technological Institute, Aarhus (Denmark); Christensen, Rolf [Alfa Laval, Lund (Sweden); Rasmussen, Bjarne D. [Grundfos, Bjerringbro (Denmark); Gram, S.; Fredborg Jakobsen, D. [Svedan Industri Koeleanlaeg, Greve (Denmark)

2013-09-15

The report describes the development of a highly effective ammonia heat pump. Heat pumps play an increasingly important role in the search for more effective use of energy in our society. Highly efficient heat pumps can contribute to reduced energy consumption and improved economy of the systems which they are a part of. An ammonia heat pump with high pressure reciprocating compressor and a novel split condenser was developed to prove potential for efficiency optimization. The split of the condenser in two parts can be utilized to obtain smaller temperature approaches and, thereby, improved heat pump efficiency at an equal heat exchanger area, when compared to the traditional solution with separate condenser and de-superheater. The split condenser design can also be exploited for heating a significant share of the total heating capacity to a temperature far above the condensing temperature. Furthermore, the prototype heat pump was equipped with a plate type evaporator combined with a U-turn separator with a minimum liquid height and a liquid pump with the purpose of creating optimum liquid circulation ratio for the highest possible heat transfer coefficients at the lowest possible pressure drop. The test results successfully confirmed the highest possible efficiency; a COP of 4.3 was obtained when heating water from 40 deg. C to 80 deg. C while operating with evaporating/condensing temperatures of +20 deg C/+73 deg C. (Author)

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

Pancreatic bicarbonate secretion involves two proton pumps.

Science.gov (United States)

Novak, Ivana; Wang, Jing; Henriksen, Katrine L; Haanes, Kristian A; Krabbe, Simon; Nitschke, Roland; Hede, Susanne E

2011-01-07

Pancreas secretes fluid rich in digestive enzymes and bicarbonate. The alkaline secretion is important in buffering of acid chyme entering duodenum and for activation of enzymes. This secretion is formed in pancreatic ducts, and studies to date show that plasma membranes of duct epithelium express H(+)/HCO(3)(-) transporters, which depend on gradients created by the Na(+)/K(+)-ATPase. However, the model cannot fully account for high-bicarbonate concentrations, and other active transporters, i.e. pumps, have not been explored. Here we show that pancreatic ducts express functional gastric and non-gastric H(+)-K(+)-ATPases. We measured intracellular pH and secretion in small ducts isolated from rat pancreas and showed their sensitivity to H(+)-K(+) pump inhibitors and ion substitutions. Gastric and non-gastric H(+)-K(+) pumps were demonstrated on RNA and protein levels, and pumps were localized to the plasma membranes of pancreatic ducts. Quantitative analysis of H(+)/HCO(3)(-) and fluid transport shows that the H(+)-K(+) pumps can contribute to pancreatic secretion in several species. Our results call for revision of the bicarbonate transport physiology in pancreas, and most likely other epithelia. Furthermore, because pancreatic ducts play a central role in several pancreatic diseases, it is of high relevance to understand the role of H(+)-K(+) pumps in pathophysiology.

The operating reliability of the reactor coolant pump

International Nuclear Information System (INIS)

Grancy, W.

1996-01-01

There is a strong tendency among operating companies and manufacturers of nuclear power stations to further increase safety and operating availability of the plant and of its components. This applies also and particularly to reactor coolant pumps for the primary circuit of nuclear power stations of the type PWR. For 3 decades, ANDRITZ has developed and built such pumps and has attached great importance to the design of the complete pump rotor and of its essential surrounding elements, such as bearing and shaft seal. Apart from questions connected with design functioning of the pump there is one question of top priority: the operating reliability of the reactor coolant pump. The pump rotor (together with the rotor of the drive motor) is the only component within the primary system that permanently rotates at high speed during operation of the reactor plant. Many questions concerning design and configuration of such components cannot be answered purely theoretically, or they can only be answered partly. Therefore comprehensive development work and testing was necessary to increase the operating reliability of the pump rotor itself and of its surrounding elements. This contribution describes the current status of development and, as a focal point, discusses shaft sealing solutions elaborated so far. In this connection also a sealing system will be presented which aims for the first time at using a two-stage mechanical seal in reactor coolant pumps

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

The lunar thermal ice pump

Energy Technology Data Exchange (ETDEWEB)

Schorghofer, Norbert [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii, Honolulu, HI 96822 (United States); Aharonson, Oded, E-mail: norbert@hawaii.edu [Helen Kimmel Center for Planetary Science, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 76100 (Israel)

2014-06-20

It has long been suggested that water ice can exist in extremely cold regions near the lunar poles, where sublimation loss is negligible. The geographic distribution of H-bearing regolith shows only a partial or ambiguous correlation with permanently shadowed areas, thus suggesting that another mechanism may contribute to locally enhancing water concentrations. We show that under suitable conditions, water molecules can be pumped down into the regolith by day-night temperature cycles, leading to an enrichment of H{sub 2}O in excess of the surface concentration. Ideal conditions for pumping are estimated and found to occur where the mean surface temperature is below 105 K and the peak surface temperature is above 120 K. These conditions complement those of the classical cold traps that are roughly defined by peak temperatures lower than 120 K. On the present-day Moon, an estimated 0.8% of the global surface area experiences such temperature variations. Typically, pumping occurs on pole-facing slopes in small areas, but within a few degrees of each pole the equator-facing slopes are preferred. Although pumping of water molecules is expected over cumulatively large areas, the absolute yield of this pump is low; at best, a few percent of the H{sub 2}O delivered to the surface could have accumulated in the near-surface layer in this way. The amount of ice increases with vapor diffusivity and is thus higher in the regolith with large pore spaces.

Application of the FFTBM method and the power relative contribution to the discharge transitory of the recirculation pumps of a BWR

International Nuclear Information System (INIS)

Castillo D, R.; Ortiz V, J.; Fuentes M, L.

2013-10-01

In this work was realized the simulation of the discharge transitory of both recirculation pumps of a BWR with the Simulate-3K code. This type of transitory is used in the stability analyses for the licensing of the fuel reload. An analysis of the precision of the simulation is also presented, using the FFTBM method jointly with the power relative contribution. This way, instead of determining the total precision of the calculation, a weighed precision is obtained by the contribution of each relevant parameter of the transitory. The results show that the precision of the simulation is acceptable due to the small magnitude of the merit figure of the width total average. The error in the merit figure comes mainly from the parameters total flow in the core and temperature of the fuel in the core. (Author)

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

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

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

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.

Oil supply on demand: Oil pumps in serial application; Bedarfsgerechte Oelversorgung: Regeloelpumpen im Serieneinsatz

Energy Technology Data Exchange (ETDEWEB)

Lamparski, C. [S H W Automotive GmbH und Co. KG, Bad Schussenried (Germany)

2007-07-01

Usually, constant displacement oil pumps are used for the oil supply of combustion engines. Gerotor, helical or spur gear pumps or vane pumps are the most common solutions. The disadvantage of the mentioned design is the oil delivery as function of pump speed, independent from the engine needs. Variability of oil delivery for reduction of hydraulic losses is the logical consequence. The first variable displacement oil pump which has fulfilled this requirement is the Internal Regulated Oil Pump (IRP). The mass production of this oil pump started in 2002. The solution for outer gear pumps and vane cells followed shortly. The following contribution gives a summary of different technical concepts for adjusting of oil delivery, beginning with pump pressure as a leading value till map regulation and its transformation in mass production products. (orig.)

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

Pump-probe surface photovoltage spectroscopy measurements on semiconductor epitaxial layers

International Nuclear Information System (INIS)

Jana, Dipankar; Porwal, S.; Sharma, T. K.; Oak, S. M.; Kumar, Shailendra

2014-01-01

Pump-probe Surface Photovoltage Spectroscopy (SPS) measurements are performed on semiconductor epitaxial layers. Here, an additional sub-bandgap cw pump laser beam is used in a conventional chopped light geometry SPS setup under the pump-probe configuration. The main role of pump laser beam is to saturate the sub-bandgap localized states whose contribution otherwise swamp the information related to the bandgap of material. It also affects the magnitude of Dember voltage in case of semi-insulating (SI) semiconductor substrates. Pump-probe SPS technique enables an accurate determination of the bandgap of semiconductor epitaxial layers even under the strong influence of localized sub-bandgap states. The pump beam is found to be very effective in suppressing the effect of surface/interface and bulk trap states. The overall magnitude of SPV signal is decided by the dependence of charge separation mechanisms on the intensity of the pump beam. On the contrary, an above bandgap cw pump laser can be used to distinguish the signatures of sub-bandgap states by suppressing the band edge related feature. Usefulness of the pump-probe SPS technique is established by unambiguously determining the bandgap of p-GaAs epitaxial layers grown on SI-GaAs substrates, SI-InP wafers, and p-GaN epilayers grown on Sapphire substrates

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.

Entropy, pricing and productivity of pumped-storage

Science.gov (United States)

Karakatsanis, Georgios; Tyralis, Hristos; Tzouka, Katerina

2016-04-01

Pumped-storage constitutes today a mature method of bulk electricity storage in the form of hydropower. This bulk electricity storability upgrades the economic value of hydropower as it may mitigate -or even neutralize- stochastic effects deriving from various geophysical and socioeconomic factors, which produce numerous load balance inefficiencies due to increased uncertainty. Pumped-storage further holds a key role for unifying intermittent renewable (i.e. wind, solar) units with controllable non-renewable (i.e. nuclear, coal) fuel electricity generation plants into integrated energy systems. We develop a set of indicators for the measurement of performance of pumped-storage, in terms of the latter's energy and financial contribution to the energy system. More specifically, we use the concept of entropy in order to examine: (1) the statistical features -and correlations- of the energy system's intermittent components and (2) the statistical features of electricity demand prediction deviations. In this way, the macroeconomics of pumped-storage emerges naturally from its statistical features (Karakatsanis et al. 2014). In addition, these findings are combined to actual daily loads. Hence, not only the amount of energy harvested from the pumped-storage component is expected to be important, but the harvesting time as well, as the intraday price of electricity varies significantly. Additionally, the structure of the pumped-storage market proves to be a significant factor as well for the system's energy and financial performance (Paine et al. 2014). According to the above, we aim at postulating a set of general rules on the productivity of pumped-storage for (integrated) energy systems. Keywords: pumped-storage, storability, economic value of hydropower, stochastic effects, uncertainty, energy systems, entropy, intraday electricity price, productivity References 1. Karakatsanis, Georgios et al. (2014), Entropy, pricing and macroeconomics of pumped-storage systems

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

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....

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

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.

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

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

Economic COP Optimization of a Heat Pump with Hierarchical Model Predictive Control

DEFF Research Database (Denmark)

Tahersima, Fatemeh; Stoustrup, Jakob; Rasmussen, Henrik

2012-01-01

A low-temperature heating system is studied in this paper. It consists of hydronic under-floor heating pipes and an air/ground source heat pump. The heat pump in such a setup is conventionally controlled only by feed-forwarding the ambient temperature. Having shown >10% cut-down on electricity bi....... The proposed control strategy is a leap forward towards balanced load control in Smart Grids where individual heat pumps in detached houses contribute to preserve load balance through intelligent electricity pricing policies....

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...

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

Thermal spin pumping mediated by magnons in the semiclassical regime

International Nuclear Information System (INIS)

Nakata, Kouki

2012-01-01

We microscopically analyze thermal spin pumping mediated by magnons, at the interface between a ferromagnetic insulator and a non-magnetic metal, in the semiclassical regime. The generation of a spin current is discussed by calculating the thermal spin transfer torque, which breaks the spin conservation law for conduction electrons and operates the coherent magnon state. Inhomogeneous thermal fluctuations between conduction electrons and magnons induce a net spin current, which is pumped into the adjacent non-magnetic metal. The pumped spin current is proportional to the temperature difference. When the effective temperature of magnons is lower than that of conduction electrons, localized spins lose spin angular momentum by emitting magnons and conduction electrons flip from down to up by absorbing all the emitted momentum, and vice versa. Magnons at the zero mode cannot contribute to thermal spin pumping because they are eliminated by the spin-flip condition. Consequently thermal spin pumping does not cost any kind of applied magnetic fields

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.

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 ...

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

Development for LMR coolant technology - Development of a submersible-in-pool electromagnetic pump

Energy Technology Data Exchange (ETDEWEB)

Hong, Sang Hee; Kim, Hee Reyoung; Lee, Sang Don; Seo, Chun Ho [Seoul National University, Seoul (Korea, Republic of); Cho, Su Won [Kyungki University, Suwon (Korea, Republic of)

1995-08-01

The conceptual and detailed designs of an annular linear induction electromagnetic pump of small scale submersible-in-pool type are performed for the purpose of domestic development of the pumps used for the high-temperature natrium coolant transportation in liquid metal reactors. The pump drawings for and input power of 1,100 VA, an input frequency of 17 Hz, a maximum flowrate of 60 l/min and a maximum operation temperature of 600 deg C are obtained from the optimum design analyses by solving MHD and equivalent circuit equations. The characteristics of pump materials in the high temperature and neutron irradiation environment are reflected in designing the pump, and theoretical analyses for improving the pump performance and efficiency are tried through calculations of magnetic flux and temperature distributions inside the pump. The present project contributes to the further design of engineering proto-type electromagnetic pump with higher capacity and the development of liquid metal reactor with innovative simplicity. 44 refs., 4 tabs., 33 figs. (author)

Japanese contributions to IAEA INTOR workshop, phase IIA

International Nuclear Information System (INIS)

Fujisawa, Noboru; Sugihara, Masayoshi; Shimada, Michiya; Saito, Seiji.

1982-11-01

This report corresponds to Chapter VI of Japanese contribution report to IAEA INTOR workshop, Phase IIA. Special emphasis is placed on pumped limiter analysis for comparative studies between limiter and divertor concepts. Pumping characteristics of divertor/limiter and radiation cooling of diverted plasmas by impurities are also intensively studied. (author)

Bacterial Multidrug Efflux Pumps: Much More Than Antibiotic Resistance Determinants.

Science.gov (United States)

Blanco, Paula; Hernando-Amado, Sara; Reales-Calderon, Jose Antonio; Corona, Fernando; Lira, Felipe; Alcalde-Rico, Manuel; Bernardini, Alejandra; Sanchez, Maria Blanca; Martinez, Jose Luis

2016-02-16

Bacterial multidrug efflux pumps are antibiotic resistance determinants present in all microorganisms. With few exceptions, they are chromosomally encoded and present a conserved organization both at the genetic and at the protein levels. In addition, most, if not all, strains of a given bacterial species present the same chromosomally-encoded efflux pumps. Altogether this indicates that multidrug efflux pumps are ancient elements encoded in bacterial genomes long before the recent use of antibiotics for human and animal therapy. In this regard, it is worth mentioning that efflux pumps can extrude a wide range of substrates that include, besides antibiotics, heavy metals, organic pollutants, plant-produced compounds, quorum sensing signals or bacterial metabolites, among others. In the current review, we present information on the different functions that multidrug efflux pumps may have for the bacterial behaviour in different habitats as well as on their regulation by specific signals. Since, in addition to their function in non-clinical ecosystems, multidrug efflux pumps contribute to intrinsic, acquired, and phenotypic resistance of bacterial pathogens, the review also presents information on the search for inhibitors of multidrug efflux pumps, which are currently under development, in the aim of increasing the susceptibility of bacterial pathogens to antibiotics.

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...

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)

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.

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

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...

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.

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.

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.

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

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

Full Text Available The ram pump is a device which pumps a portion of input discharge to the pumping system in a significant height by using renewable energy of water hammer. The complexities of flow hydraulic on one hand and on the other hand the use of simplifying assumptions in ram pumps have caused errors in submitted analytical models for analyzing running cycle of these pumps. In this study it has been tried to modify the governing analytical model on hydraulic performance of these pumps in pumping stage. In this study by creating a logical division, the cycle of the ram pump was divided into three stages of acceleration, pumping and recoil and the governing equations on each stage of cycling are presented by using method of characteristics. Since the closing of impulse valve is nonlinear, velocity loss in pumping stage is considered nonlinearly. Also the governing equations in pumping stage were modified by considering disc elasticity of impulse valve and changing volume of the pump body when the water hammer phenomenon is occurred. In order to evaluate results and determine empirical factors of the proposed analytical model, a physical model of the ram pump is made with internal diameter of 51 mm. Results of this study are divided into several parts. In the first part, loss coefficients of the impulse valve were measured experimentally and empirical equations of drag coefficient and friction coefficient of the impulse valve were submitted by using nonlinear regression. In the second part, results were evaluated by using experimental data taken from this study. Evaluation of statistical error functions showed that the proposed model has good accuracy for predicting experimental observations. In the third part, in order to validate the results in pumping stage, the analytical models of Lansford and Dugan (1941 and Tacke (1988 were used and the error functions resulted from prediction of experimental observations were investigated through analytical models of

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.

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

The role of large‐scale heat pumps for short term integration of renewable energy

DEFF Research Database (Denmark)

Mathiesen, Brian Vad; Blarke, Morten; Hansen, Kenneth

2011-01-01

technologies is focusing on natural working fluid hydrocarbons, ammonia, and carbon dioxide. Large-scale heat pumps are crucial for integrating 50% wind power as anticipated to be installed in Denmark in 2020, along with other measures. Also in the longer term heat pumps can contribute to the minimization...... savings with increased wind power and may additionally lead to economic savings in the range of 1,500-1,700 MDKK in total in the period until 2020. Furthermore, the energy system efficiency may be increased due to large heat pumps replacing boiler production. Finally data sheets for large-scale ammonium......In this report the role of large-scale heat pumps in a future energy system with increased renewable energy is presented. The main concepts for large heat pumps in district heating systems are outlined along with the development for heat pump refrigerants. The development of future heat pump...

Heat pumps - Where are the big ones?; Waermepumpen - Wo sind die Grossen?

Energy Technology Data Exchange (ETDEWEB)

Rognon, F.

2002-07-01

These comprehensive proceedings contain seven presentations made at the 9th Conference held by the Swiss Research Programme on Environmental Heat, Combined Heat and Power Generation (CHP) and Refrigeration in Burgdorf, Switzerland in June 2002. Fabrice Rognon, head of the Swiss Federal Office of Energy's Programme on environmental heat, CHP and refrigeration reports on the promotion of renewable energy and targets for large heat pump installations, Peter Bailer presents a technical review of larger heat pump plant in Europe, Bertrand Rochat describes a building in Vevey, Switzerland, that uses a combination of heat pump and geothermal probes to provide heat and cold and Herbert Giger describes a contracting-based solution used to provide heating energy for a housing estate with 8 apartment blocks in Thun, Switzerland. Further contributions include one from Jean-Philippe Borel providing information on two examples of the production of heat and cold at the same time and a contribution by Beat Kobel on a source of heat often 'forgotten' in municipalities - wastewater. The final contribution is from Bernhard Eggen on the use of heat from the Aare river in Bern, Switzerland.

Comparison of different lubricating oil pump systems for combustion engines. Vergleich verschiedener Schmieroelpumpen-Systeme bei Verbrennungsmotoren

Energy Technology Data Exchange (ETDEWEB)

Eisenmann, S; Haerle, C; Schreiber, B

1994-10-01

The present day and future legislative requirements with regard to fuel consumption and improvement of emission values are forcing the automotive industry to continually improve its technology. However, the investments made in such technical innovations should be set-off by the results. The lubricating oil pump can make an important contribution with optimum design and through the choice of the most adequate pump system. Over the last 17 years, SHW has worked very closely with the automotive industry on the development of lubricating oil pumps. One of the results of this research work is a Suction Regulated Pump (SRP) which distinguishes itself from conventional pumps through its lower drive power. We will proceed to explain this pump system, comparing it with the present day pump systems. (orig.)

High-k shallow traps observed by charge pumping with varying discharging times

International Nuclear Information System (INIS)

Ho, Szu-Han; Chen, Ching-En; Tseng, Tseung-Yuen; Chang, Ting-Chang; Lu, Ying-Hsin; Lo, Wen-Hung; Tsai, Jyun-Yu; Liu, Kuan-Ju; Wang, Bin-Wei; Cao, Xi-Xin; Chen, Hua-Mao; Cheng, Osbert; Huang, Cheng-Tung; Chen, Tsai-Fu

2013-01-01

In this paper, we investigate the influence of falling time and base level time on high-k bulk shallow traps measured by charge pumping technique in n-channel metal-oxide-semiconductor field-effect transistors with HfO 2 /metal gate stacks. N T -V high level characteristic curves with different duty ratios indicate that the electron detrapping time dominates the value of N T for extra contribution of I cp traps. N T is the number of traps, and I cp is charge pumping current. By fitting discharge formula at different temperatures, the results show that extra contribution of I cp traps at high voltage are in fact high-k bulk shallow traps. This is also verified through a comparison of different interlayer thicknesses and different Ti x N 1−x metal gate concentrations. Next, N T -V high level characteristic curves with different falling times (t falling time ) and base level times (t base level ) show that extra contribution of I cp traps decrease with an increase in t falling time . By fitting discharge formula for different t falling time , the results show that electrons trapped in high-k bulk shallow traps first discharge to the channel and then to source and drain during t falling time . This current cannot be measured by the charge pumping technique. Subsequent measurements of N T by charge pumping technique at t base level reveal a remainder of electrons trapped in high-k bulk shallow traps

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 ...

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.

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.)

Na(+)/K(+) pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches.

Science.gov (United States)

Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

2016-09-02

The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na(+)/K(+) pump current to such bursting activity has not been well studied. We used monensin, a Na(+)/H(+) antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs(+). The decreased period could also occur if the pump was inhibited with strophanthidin or K(+)-free saline. Our monensin results were reproduced in model, which explains the pump's contributions to bursting activity based on Na(+) dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks.

Work plan, AP-102 mixer pump removal and pump replacement

International Nuclear Information System (INIS)

Jimenez, R.F.

1994-01-01

The objective of this work plan is to plan the steps and estimate the costs required to remove the failed AP-102 mixer pump, and to plan and estimate the cost of the necessary design and specification work required to order a new, but modified, mixer pump including the pump and pump pit energy absorbing design. The main hardware required for the removal of the mixer is as follows: a flexible receiver and blast shield; a metal container for the pulled mixer pump; and a trailer and strongback to haul and manipulate the container. Additionally: a gamma scanning device will be needed to detect the radioactivity emanating from the mixer as it is pulled from the tank; a water spray system will be required to remove tank waste from the surface of the mixer as it is pulled from the AP-102 tank; and a lifting yoke to lift the mixer from the pump pit (the SY-101 Mixer Lifting Yoke will be used). A ''green house'' will have to be erected over the AP-102 pump pit and an experienced Hoisting and Rigging crew must be assembled and trained in mixer pump removal methods before the actual removal is undertaken

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.

Electromagnetic pump technology

International Nuclear Information System (INIS)

Prabhakar, R.

1994-01-01

Fast Breeder Reactors have an important role to play in our nuclear power programme. Liquid metal sodium is used as the coolant for removing fission heat generated in fast reactors and a distinctive physical property of sodium is its high electrical conductivity. This enables application of electromagnetic (EM) pumps, working on same principle as electric motors, for pumping liquid sodium. Due to its lower efficiency as compared to centrifugal pumps, use of EM pumps has been restricted to reactor auxiliary circuits and experimental facilities. As part of our efforts to manufacture fast reactor components indigenously, work on the development of two types of EM pumps namely flat linear induction pump (FLIP) and annular linear induction pump (ALIP) has been undertaken. Design procedures based on an equivalent circuit approach have been established and results from testing a 5.6 x 10E-3 Cum/s (20 Cum/h) FLIP in a sodium loop were used to validate the procedure. (author). 7 refs., 6 figs

Pumping life

DEFF Research Database (Denmark)

Sitsel, Oleg; Dach, Ingrid; Hoffmann, Robert Daniel

2012-01-01

The name PUMPKIN may suggest a research centre focused on American Halloween traditions or the investigation of the growth of vegetables – however this would be misleading. Researchers at PUMPKIN, short for Centre for Membrane Pumps in Cells and Disease, are in fact interested in a large family o......’. Here we illustrate that the pumping of ions means nothing less than the pumping of life....

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)

Champagne Heat Pump

Science.gov (United States)

Jones, Jack A.

2004-01-01

The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

Pumping of methane by an ionization assisted Zr/Al getter pump

International Nuclear Information System (INIS)

Shen, G.L.

1987-01-01

The pumping of methane by an ionization assisted Zr/Al getter pump has been investigated. This pump consists of 12 pieces of ring getters. A spiral shape W filament is located within the ring getters. A bias voltage is applied across the filament and the getter itself. The experiments have shown that (1) when the bias voltage is turned off, the pumping speed of the getter pump for methane increases exponentially with the filament temperature; (2) when the filament temperature is held constant, its pumping speed varies directly with the ionization electron current; (3) when the filament temperature is 2063 0 C and the electron current is 57 mA, the pumping speed of the Zr/Al getter pump is 475 ml/s, and the specific speed is 16.8 ml/s cm 2 ; and (4) an activation energy and critical temperature measured for methane molecules decomposition are, respectively, 47.4 kcal/mol and about 1700 0 C. Analysis of the results indicates that methane is pumped by an ionization assisted Zr/Al getter pump not because of the adsorption and the diffusion of methane molecules directly, but because methane molecules are decomposed as C and H 2 through a catalysis of the hot W filament, carbon is adsorbed on the surface of the W filament, and is diffused into the interior of the W lattice. H 2 is immediately absorbed by the Zr/Al getters. Besides, electron impact with CH 4 would result in the additional decomposition and ionization, then the effect of electron bombardment enhances methane pumping by the Zr/Al getters

Pump-probe study of the formation of rubidium molecules by ultrafast photoassociation of ultracold atoms

Science.gov (United States)

McCabe, David J.; England, Duncan G.; Martay, Hugo E. L.; Friedman, Melissa E.; Petrovic, Jovana; Dimova, Emiliya; Chatel, Béatrice; Walmsley, Ian A.

2009-09-01

An experimental pump-probe study of the photoassociative creation of translationally ultracold rubidium molecules is presented together with numerical simulations of the process. The formation of loosely bound excited-state dimers is observed as a first step toward a fully coherent pump-dump approach to the stabilization of Rb2 into its lowest ground vibrational states. The population that contributes to the pump-probe process is characterized and found to be distinct from a background population of preassociated molecules.

Breastfeeding FAQs: Pumping

Science.gov (United States)

... of pump is best? You can buy or rent a breast pump from lactation consultants, hospitals, retail ... place to do it. Many companies offer their employees pumping and nursing areas. If yours doesn't, ...

Development and evaluation of cryosorption pump and cryotrapping pump for CTR applications

International Nuclear Information System (INIS)

Kuribayashi, S.; Ota, H.; Sato, H.

1986-01-01

In order to obtain the engineering data to design compound cryopump for CTR, the authors tested the cryosorption pump and cryotrapping pump. The cryosorption panel was consisted of coconut charcoal metallically bonded to 4.2K cryopanel by brazing. The initial pumping speed of helium of cryosorption pump was found to be ≅2.2 iota/scm/sup 2/. The speed dropped off with loading (about 8 Torr iota/cm/sup 2/) to 1.5 iota/scm/sup 2/. The initial helium pumping speed of the 4.2K cryotrapping pump by argon spray was found to be ≅6 iota/scm/sup 2/. The speed, however, dropped off with loading (≅0.3 Torr iota/cm/sup 2/) to less than 5%. These results indicate that the cryosorption pump by coconut charcoal is superior to the cryotrapping pump, because the capacity of the former is larger than the latter

Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

Science.gov (United States)

Hwang, In H.; Lee, Ja H.

1991-01-01

The authors consider the relation between the threshold pumping intensity, the material properties, the resonator parameters, and the ultimate slope efficiencies of various solid-state laser materials for solar pumping. They clarify the relation between the threshold pump intensity and the material parameters and the relation between the ultimate slope efficiency and the laser resonator parameters such that a design criterion for the solar-pumped solid-state laser can be established. Among the laser materials evaluated, alexandrite has the highest slope efficiency of about 12.6 percent; however, it does not seem to be practical for a solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AM0) solar constants and its slope efficiency is about 12 percent when thermal deformation is completely prevented.

Norwegian participation in the IEA Heat Pump Programme Annex 34 - final report

Energy Technology Data Exchange (ETDEWEB)

Nordtvedt, S.R.

2012-07-01

This report is the Norwegian team contribution to Task A within the IEA Heat Pumps Programme Annex 34 on #Left Double Quotation Mark#Thermally driven heat pumps#Right Double Quotation Mark#. It aims to give an overview of the thermally driven heat pump (TDHP) and chiller (TDC) market, recent developments in the area of TDHP and TDC, as well as to give an outlook of the progress of this technology. There are no Norwegian manufacturers on the TDHP market. There are only seven existing thermally driven absorption system installations in Norway. Three are district heat driven water/LiBr chillers, one is a steam driven water/LiBr chiller, one water/LiBr heat pump for flue gas condensation in a wood chip heating unit, and two gas driven ammonia-water chillers. The future market for thermally driven heat pumps and chillers in Norway is expected to be in combination of biomass, district heat or waste heat. (Author)

Pumping station design for a pumped-storage wind-hydro power plant

International Nuclear Information System (INIS)

Anagnostopoulos, John S.; Papantonis, Dimitris E.

2007-01-01

This work presents a numerical study of the optimum sizing and design of a pumping station unit in a hybrid wind-hydro plant. The standard design that consists of a number of identical pumps operating in parallel is examined in comparison with two other configurations, using one variable-speed pump or an additional set of smaller jockey pumps. The aim is to reduce the amount of the wind generated energy that cannot be transformed to hydraulic energy due to power operation limits of the pumps and the resulting step-wise operation of the pumping station. The plant operation for a period of one year is simulated by a comprehensive evaluation algorithm, which also performs a detailed economic analysis of the plant using dynamic evaluation methods. A preliminary study of the entire plant sizing is carried out at first using an optimization tool based on evolutionary algorithms. The performance of the three examined pumping station units is then computed and analyzed in a comparative study. The results reveal that the use of a variable-speed pump constitutes the most effective and profitable solution, and its superiority is more pronounced for less dispersed wind power potential

The Contribution of Compressional Magnetic Pumping to the Energization of the Earth's Outer Electron Radiation Belt During High-Speed Stream-Driven Storms

Science.gov (United States)

Borovsky, Joseph E.; Horne, Richard B.; Meredith, Nigel P.

2017-12-01

Compressional magnetic pumping is an interaction between cyclic magnetic compressions and pitch angle scattering with the scattering acting as a catalyst to allow the cyclic compressions to energize particles. Compressional magnetic pumping of the outer electron radiation belt at geosynchronous orbit in the dayside magnetosphere is analyzed by means of computer simulations, wherein solar wind compressions of the dayside magnetosphere energize electrons with electron pitch angle scattering by chorus waves and by electromagnetic ion cyclotron (EMIC) waves. The magnetic pumping is found to produce a weak bulk heating of the electron radiation belt, and it also produces an energetic tail on the electron energy distribution. The amount of energization depends on the robustness of the solar wind compressions and on the amplitude of the chorus and/or EMIC waves. Chorus-catalyzed pumping is better at energizing medium-energy (50-200 keV) electrons than it is at energizing higher-energy electrons; at high energies (500 keV-2 MeV) EMIC-catalyzed pumping is a stronger energizer. The magnetic pumping simulation results are compared with energy diffusion calculations for chorus waves in the dayside magnetosphere; in general, compressional magnetic pumping is found to be weaker at accelerating electrons than is chorus-driven energy diffusion. In circumstances when solar wind compressions are robust and when EMIC waves are present in the dayside magnetosphere without the presence of chorus, EMIC-catalyzed magnetic pumping could be the dominant energization mechanism in the dayside magnetosphere, but at such times loss cone losses will be strong.

BWR series pump recirculation system

International Nuclear Information System (INIS)

Dillmann, C.W.

1992-01-01

This patent describes a recirculation system for driving reactor coolant water contained in an annular downcomer defined between a boiling water reactor vessel and a reactor core spaced radially inwardly therefrom. It comprises a plurality of circumferentially spaced second pumps disposed in the downcomer, each including an inlet for receiving from the downcomer a portion of the coolant water as pump inlet flow, and an outlet for discharging the pump inlet flow pressurized in the second pump as pump outlet flow; and means for increasing pressure of the pump inlet flow at the pump inlet including a first pump disposed in series flow with the second pump for first receiving the pump inlet flow from the downcomer and discharging to the second pump inlet flow pressurized in the first pump

Early outcome of off-pump versus on-pump coronary revascularization

African Journals Online (AJOL)

Introduction: The use of coronary artery bypass surgery (CABG) with cardiopulmonary bypass (CPB) or without CPB technique (off-pump) can be associated with different mortality and morbidity and their outcomes remain uncertain. The goal of this study was to evaluate the early outcome of on-pump versus off-pump CABG.

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.

TFTR ultrahigh-vacuum pumping system incorporating mercury diffusion pumps

International Nuclear Information System (INIS)

Sink, D.A.; Sniderman, M.

1976-06-01

The TFTR vacuum vessel will have a system of four 61 cm diameter mercury diffusion pumps to provide a base pressure in the 10 -8 to 10 -9 Torr range as well as a low impurity level within the vessel. The system, called the Torus Vacuum Pumping System (TVPS), will be employed with the aid of an occasional 250 0 C bakeout in situ as well as periodic applications of aggressive discharge cleaning. The TVPS is an ultrahigh-vacuum (UHV) system using no elastomers as well as being a closed system with respect to tritium or any tritiated gases. The backing system employing approximately 75 all-metal isolation valves is designed with the features of redundancy and flexibility employed in a variety of ways to meet the fundamental requirements and functions enumerated for the TVPS. Since the design, is one which is a modification of the conceptual design of the TVPS, those features which have changed are discussed. Calculations are presented for the major performance parameters anticipated for the TVPS and include conductances, effective pumping speeds, base pressures, operating parameters, getter pump parameters, and calculations of time constants associated with leak checking. Modifications in the vacuum pumping system for the guard regions on the twelve bellows sections are presented so that it is compatible with the main TVPS. The bellows pumping system consists of a mechanical pump unit, a zirconium aluminum getter pump unit and a residual gas analyzer. The control and management of the TVPS is described with particular attention given to providing both manual and automatic control at a local station and at the TFTR Central Control. Such operations as testing, maintenance, leak checking, startup, bakeout, and various other operations are considered in some detail. Various aspects related to normal pulsing, discharge cleaning, non-tritium operations and tritium operations are also taken into consideration. A cost estimate is presented

Use of ultrafast dispersed pump-dump-probe and pump-repump-probe spectroscopies to explore the light-induced dynamics of peridinin in solution.

Science.gov (United States)

Papagiannakis, Emmanouil; Vengris, Mikas; Larsen, Delmar S; van Stokkum, Ivo H M; Hiller, Roger G; van Grondelle, Rienk

2006-01-12

Optical pump-induced dynamics of the highly asymmetric carotenoid peridinin in methanol was studied by dispersed pump-probe, pump-dump-probe, and pump-repump-probe transient absorption spectroscopy in the visible region. Dispersed pump-probe measurements show that the decay of the initially excited S2 state populates two excited states, the S1 and the intramolecular charge-transfer (ICT) state, at a ratio determined by the excitation wavelength. The ensuing spectral evolution occurs on the time scale of a few picoseconds and suggests the equilibration of these states. Dumping the stimulated emission of the ICT state with an additional 800-nm pulse after 400- and 530-nm excitation preferentially removes the ICT state contribution from the broad excited-state absorption, allowing for its spectral characterization. At the same time, an unrelaxed ground-state species, which has a subpicosecond lifetime, is populated. The application of the 800-nm pulse at early times, when the S2 state is still populated, led to direct generation of the peridinin cation, observed for the first time in a transient absorption experiment. The excited and ground electronic states manifold of peridinin has been reconstructed using target analysis; this approach combined with the measured multipulse spectroscopic data allows us to estimate the spectra and time scales of the corresponding transient states.

Multidrug Efflux Pumps in Staphylococcus aureus: an Update

Science.gov (United States)

Costa, Sofia Santos; Viveiros, Miguel; Amaral, Leonard; Couto, Isabel

2013-01-01

The emergence of infections caused by multi- or pan-resistant bacteria in the hospital or in the community settings is an increasing health concern. Albeit there is no single resistance mechanism behind multiresistance, multidrug efflux pumps, proteins that cells use to detoxify from noxious compounds, seem to play a key role in the emergence of these multidrug resistant (MDR) bacteria. During the last decades, experimental data has established their contribution to low level resistance to antimicrobials in bacteria and their potential role in the appearance of MDR phenotypes, by the extrusion of multiple, unrelated compounds. Recent studies suggest that efflux pumps may be used by the cell as a first-line defense mechanism, avoiding the drug to reach lethal concentrations, until a stable, more efficient alteration occurs, that allows survival in the presence of that agent. In this paper we review the current knowledge on MDR efflux pumps and their intricate regulatory network in Staphylococcus aureus, a major pathogen, responsible from mild to life-threatening infections. Particular emphasis will be given to the potential role that S. aureus MDR efflux pumps, either chromosomal or plasmid-encoded, have on resistance towards different antimicrobial agents and on the selection of drug - resistant strains. We will also discuss the many questions that still remain on the role of each specific efflux pump and the need to establish appropriate methodological approaches to address all these questions. PMID:23569469

Multidrug Efflux Pumps in Staphylococcus aureus: an Update.

Science.gov (United States)

Costa, Sofia Santos; Viveiros, Miguel; Amaral, Leonard; Couto, Isabel

2013-01-01

The emergence of infections caused by multi- or pan-resistant bacteria in the hospital or in the community settings is an increasing health concern. Albeit there is no single resistance mechanism behind multiresistance, multidrug efflux pumps, proteins that cells use to detoxify from noxious compounds, seem to play a key role in the emergence of these multidrug resistant (MDR) bacteria. During the last decades, experimental data has established their contribution to low level resistance to antimicrobials in bacteria and their potential role in the appearance of MDR phenotypes, by the extrusion of multiple, unrelated compounds. Recent studies suggest that efflux pumps may be used by the cell as a first-line defense mechanism, avoiding the drug to reach lethal concentrations, until a stable, more efficient alteration occurs, that allows survival in the presence of that agent. In this paper we review the current knowledge on MDR efflux pumps and their intricate regulatory network in Staphylococcus aureus, a major pathogen, responsible from mild to life-threatening infections. Particular emphasis will be given to the potential role that S. aureus MDR efflux pumps, either chromosomal or plasmid-encoded, have on resistance towards different antimicrobial agents and on the selection of drug - resistant strains. We will also discuss the many questions that still remain on the role of each specific efflux pump and the need to establish appropriate methodological approaches to address all these questions.

Photovoltaic pump systems

Science.gov (United States)

Klockgether, J.; Kiessling, K. P.

1983-09-01

Solar pump systems for the irrigation of fields and for water supply in regions with much sunshine are discussed. For surface water and sources with a hoisting depth of 12 m, a system with immersion pumps is used. For deep sources with larger hoisting depths, an underwater motor pump was developed. Both types of pump system meet the requirements of simple installation and manipulation, safe operation, maintenance free, and high efficiency reducing the number of solar cells needed.

Damages on pumps and systems the handbook for the operation of centrifugal pumps

CERN Document Server

Merkle, Thomas

2014-01-01

Damage on Pumps and Systems. The Handbook for the Operation of Centrifugal Pumps offers a combination of the theoretical basics and practical experience for the operation of circulation pumps in the engineering industry. Centrifugal pumps and systems are extremely vulnerable to damage from a variety of causes, but the resulting breakdown can be prevented by ensuring that these pumps and systems are operated properly. This book provides a total overview of operating centrifugal pumps, including condition monitoring, preventive maintenance, life cycle costs, energy savings and economic aspects. Extra emphasis is given to the potential damage to these pumps and systems, and what can be done to prevent breakdown. Addresses specific issues about pumping of metal chips, sand, abrasive dust and other solids in fluidsEmphasis on economic and efficiency aspects of predictive maintenance and condition monitoring Uses life cycle costs (LCC) to evaluate and calculate the costs of pumping systems

Electrokinetic pump

Science.gov (United States)

Patel, Kamlesh D.

2007-11-20

A method for altering the surface properties of a particle bed. In application, the method pertains particularly to an electrokinetic pump configuration where nanoparticles are bonded to the surface of the stationary phase to alter the surface properties of the stationary phase including the surface area and/or the zeta potential and thus improve the efficiency and operating range of these pumps. By functionalizing the nanoparticles to change the zeta potential the electrokinetic pump is rendered capable of operating with working fluids having pH values that can range from 2-10 generally and acidic working fluids in particular. For applications in which the pump is intended to handle highly acidic solutions latex nanoparticles that are quaternary amine functionalized can be used.

Pumping behavior of ion pump elements at high and misaligned magnetic fields

Energy Technology Data Exchange (ETDEWEB)

Hseuh, H. C.; Jiang, W. S.; Mapes, M.

1994-11-01

The pumping speeds of several diode type ion pump elements with cell radii of 5 mm, 5.5 mm, 6 mm, 9 mm and 12 mm were measured while being subjected to a magnetic field B, ranging from 500 Gauss up to 15 KG, and misalignment angles (angles between the direction of B and the anode axis) from 0 to 13 degrees. The pumping speeds of elements with the 9 mm and 12 mm cells peaked around 1--2 KG, then dropped off rapidly with an increasing magnetic field. The pumping speeds of the smaller cell elements remained constant with an increasing magnetic field. The pumping speeds of all the elements decreased with increasing misalignment. The measured pumping speeds from this study are 3--4 times lower than the calculated pumping, speeds using previously reported empirical formulae.

Pumping behavior of ion pump elements at high and misaligned magnetic fields

International Nuclear Information System (INIS)

Hseuh, H.C.; Jiang, W.S.; Mapes, M.

1994-01-01

The pumping speeds of several diode type ion pump elements with cell radii of 5 mm, 5.5 mm, 6 mm, 9 mm and 12 mm were measured while being subjected to a magnetic field B, ranging from 500 Gauss up to 15 KG, and misalignment angles (angles between the direction of B and the anode axis) from 0 to 13 degrees. The pumping speeds of elements with the 9 mm and 12 mm cells peaked around 1--2 KG, then dropped off rapidly with an increasing magnetic field. The pumping speeds of the smaller cell elements remained constant with an increasing magnetic field. The pumping speeds of all the elements decreased with increasing misalignment. The measured pumping speeds from this study are 3--4 times lower than the calculated pumping, speeds using previously reported empirical formulae

Nonlinear performances of dual-pump amplifiers in silicon waveguides

International Nuclear Information System (INIS)

Meng Fan; Yu Chong-Xiu; Deng Yun-Yi; Yuan Jin-Hui

2012-01-01

The performances of a dual-pump parametric and Raman amplification process and the wavelength conversion in silicon waveguides are investigated. By setting the Raman contribution fraction f to be 0.043 in our analytical model, the amplification gain of the probe signal can be obtained to be over 10 dB. The pump transfer noise (PTN), the quantum noise (QN), and the total noise figure (TNF) are discussed, and the TNF has a constant value of about 4 dB in the gain bandwidth. An idler signal generated during the parametric amplification (PA) process can be used to realize the wavelength conversion in wavelength division multiplexing (WDM) systems. In addition, the pump signal parameters, the generated free carrier lifetime and effective mode area (EMA) of the waveguide are analysed for the optimization of signal gain and noise characteristics. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Liquid metal pump

International Nuclear Information System (INIS)

Pennell, W.E.

1981-01-01

A liquid metal pump comprising a shaft support structure which is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft carries an impeller and the support structure carries an impeller cage which is slidably disposed in a diffuser so as to allow complete removal of pump internals for inspection and repair. The diffuser is concentrically supported in the pump housing which also takes up all reaction forces generated by the discharge of the liquid metal from the diffuser, with floating seals arranged between impeller cage and the diffuser. The space between the diffuser and the pump housing permits the incoming liquid to essentially surround the diffuser. (author)

Rotary piston blood pumps: past developments and future potential of a unique pump type.

Science.gov (United States)

Wappenschmidt, Johannes; Autschbach, Rüdiger; Steinseifer, Ulrich; Schmitz-Rode, Thomas; Margreiter, Raimund; Klima, Günter; Goetzenich, Andreas

2016-08-01

The design of implantable blood pumps is either based on displacement pumps with membranes or rotary pumps. Both pump types have limitations to meet the clinical requirements. Rotary piston blood pumps have the potential to overcome these limitations and to merge the benefits. Compared to membrane pumps, they are smaller and with no need for wear-affected membranes and valves. Compared to rotary pumps, the blood flow is pulsatile instead of a non-physiological continuous flow. Furthermore, the risk of flow-induced blood damage and platelet activation may be reduced due to low shear stress to the blood. The past developments of rotary piston blood pumps are summarized and the main problem for long-term application is identified: insufficient seals. A new approach with seal-less drives is proposed and current research on a simplified rotary piston design is presented. Expert commentary: The development of blood pumps focuses mainly on the improvement of rotary pumps. However, medical complications indicate that inherent limitations of this pump type remain and restrict the next substantial step forward in the therapy of heart failure patients. Thus, research on different pump types is reasonable. If the development of reliable drives and bearings succeeds, rotary piston blood pumps become a promising alternative.

Systematic effects in radon mitigation by sump/pump remediation

International Nuclear Information System (INIS)

Groves-Kirkby, C.J.; Denman, A.R.; Groves-Kirkby, C.J.; Woolridge, A.C.; Woolridge, A.C.; Phillips, P.S.; Crockett, R.G.M.; Tornberg, R.

2006-01-01

Sump/Pump remediation is widely used in the United Kingdom to mitigate indoor radon gas levels in residential properties. To quantify the effectiveness of this technology, a study was made of radon concentration data from a set of 173 homes situated in radon Affected Areas in and around Northamptonshire, U.K., re-mediated using conventional sump/pump technology. This approach is characterised by a high incidence of satisfactory mitigation outcomes, with more than 75% of the sample exhibiting mitigation factors (defined as the ratio of radon concentrations following and prior to remediation) of 0.2 or better. There is evidence of a systematic trend, where houses with higher initial radon concentrations have higher mitigation factors, suggesting that the total indoor radon concentration within a dwelling can be represented by two components, one susceptible to mitigation by sump/pump remediation, the other remaining essentially unaffected by these remediation strategies. The first component can be identified with ground-radon emanating from the subsoil and bedrock geologies, percolating through the foundations of the dwelling as a component of the soil-gas, potentially capable of being attenuated by sump/pump or radon-barrier remediation. The second contribution is attributed to radon emanating from materials used in the construction of the dwelling, principally concrete and gypsum plaster-board, with a further small contribution from the natural background level, and is essentially unaffected by ground-level remediation strategies. Modelling of such a two-component radon dependency using realistic ground-radon attenuation factors in conjunction with typical structural-radon levels yields behaviour in good agreement with the observed inverse-power dependence of mitigation factor on initial radon concentration. (authors)

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

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

Review on advanced of solar assisted chemical heat pump dryer for agriculture produce

International Nuclear Information System (INIS)

Fadhel, M.I.; Sopian, K.; Daud, W.R.W.; Alghoul, M.A.

2011-01-01

Over the past three decades there has been nearly exponential growth in drying R and D on a global scale. Improving of the drying operation to save energy, improve product quality as well as reduce environmental effect remained as the main objectives of any development of drying system. A solar assisted chemical heat pump dryer is a new solar drying system, which have contributed to better cost-effectiveness and better quality dried products as well as saving energy. A solar collector is adapted to provide thermal energy in a reactor so a chemical reaction can take place. This reduces the dependency of the drying technology on fossil energy for heating. In this paper a review on advanced of solar assisted chemical heat pump dryer is presented (the system model and the results from experimental studies on the system performance are discussed). The review of heat pump dryers and solar assisted heat pump dryer is presented. Description of chemical heat pump types and the overview of chemical heat pump dryer are discussed. The combination of chemical heat pump and solar technology gives extra efficiency in utilizing energy. (author)

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.

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.

Heat pump concepts for nZEB Technology developments, design tools and testing of heat pump systems for nZEB in the USA: Country report IEA HPT Annex 40 Task 2, Task 3 and Task 4 of the USA

Energy Technology Data Exchange (ETDEWEB)

Baxter, Van D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Payne, W. Vance [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Ling, Jiazhen [Univ. of Maryland, College Park, MD (United States); Radermacher, Reinhard [Univ. of Maryland, College Park, MD (United States)

2015-12-01

The IEA HPT Annex 40 "Heat pump concepts for Nearly Zero Energy Buildings" deals with the application of heat pumps as a core component of the HVAC system for Nearly or Net Zero energy buildings (nZEB). This report covers Task 2 on the system comparison and optimisation and Task 3 dedicated to the development of adapted technologies for nZEB and field monitoring results of heat pump systems in nZEB. In the US team three institutions are involved and have worked on the following projects: The Oak Ridge National Laboratory (ORNL) will summarize development activities through the field demonstration stage for several integrated heat pump (IHP) systems electric ground-source (GS-IHP) and air-source (AS-IHP) versions and an engine driven AS-IHP version. The first commercial GS-IHP product was just introduced to the market in December 2012. This work is a contribution to Task 3 of the Annex. The University of Maryland will contribute a software development project to Task 2 of the Annex. The software ThermCom evaluates occupied space thermal comfort conditions accounting for all radiative and convective heat transfer effects as well as local air properties. The National Institute of Standards and Technology (NIST) is working on a field study effort on the NIST Net Zero Energy Residential Test Facility (NZERTF). This residential building was constructed on the NIST campus and officially opened in summer 2013. During the first year, between July 2013 and June 2014, baseline performance of the NZERTF was monitored under a simulated occupancy protocol. The house was equipped with an air-to-air heat pump which included a dedicated dehumidification operating mode. Outdoor conditions, internal loads and modes of heat pump operation were monitored. Field study results with respect to heat pump operation will be reported and recommendations on heat pump optimization for a net zero energy building will be provided. This work is a contribution to Task 3 of the Annex.

Pump integrated closed loop control. The intelligent actuator pump - state of the art and perspectives; Pumpenintegrierte Prozessregelung. Der intelligente Aktor Pumpe - Stand und Moeglichkeiten

Energy Technology Data Exchange (ETDEWEB)

Paulus, Thomas; Schullerer, Joachim; Oesterle, Manfred [KSB AG, Frankenthal (Germany)

2009-07-01

In many areas of industrial automation, centrifugal pumps and systems of centrifugal pumps are important actuators of a process und therefore a fundamental part of the entire plant. In contrary to the controlled valves, located behind the pump in the pipework system, the functions of the intelligent actuator pump or system of pumps are rarely used and noticed. With regard to the reduction of life cycle costs of the asset pump, pump integrated closed loop control of the fluid transport task has advantages over central closed loop control e.g. in a process control system. This article contains a survey of the intelligent actuator pump, its structure and functions with regard to the solution of the fluid transport task and according pump integrated closed loop control. (orig.)

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

Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Hunt, A.; Easley, S.

2012-05-01

The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

High-k shallow traps observed by charge pumping with varying discharging times

Energy Technology Data Exchange (ETDEWEB)

Ho, Szu-Han; Chen, Ching-En; Tseng, Tseung-Yuen [Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang@mail.phys.nsysu.edu.tw [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Tainan, Taiwan (China); Lu, Ying-Hsin; Lo, Wen-Hung; Tsai, Jyun-Yu; Liu, Kuan-Ju [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Wang, Bin-Wei; Cao, Xi-Xin [Department of Embedded System Engineering, Peking University, Beijing, P.R.China (China); Chen, Hua-Mao [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, Taiwan (China); Cheng, Osbert; Huang, Cheng-Tung; Chen, Tsai-Fu [Device Department, United Microelectronics Corporation, Tainan Science Park, Taiwan (China)

2013-11-07

In this paper, we investigate the influence of falling time and base level time on high-k bulk shallow traps measured by charge pumping technique in n-channel metal-oxide-semiconductor field-effect transistors with HfO{sub 2}/metal gate stacks. N{sub T}-V{sub high} {sub level} characteristic curves with different duty ratios indicate that the electron detrapping time dominates the value of N{sub T} for extra contribution of I{sub cp} traps. N{sub T} is the number of traps, and I{sub cp} is charge pumping current. By fitting discharge formula at different temperatures, the results show that extra contribution of I{sub cp} traps at high voltage are in fact high-k bulk shallow traps. This is also verified through a comparison of different interlayer thicknesses and different Ti{sub x}N{sub 1−x} metal gate concentrations. Next, N{sub T}-V{sub high} {sub level} characteristic curves with different falling times (t{sub falling} {sub time}) and base level times (t{sub base} {sub level}) show that extra contribution of I{sub cp} traps decrease with an increase in t{sub falling} {sub time}. By fitting discharge formula for different t{sub falling} {sub time}, the results show that electrons trapped in high-k bulk shallow traps first discharge to the channel and then to source and drain during t{sub falling} {sub time}. This current cannot be measured by the charge pumping technique. Subsequent measurements of N{sub T} by charge pumping technique at t{sub base} {sub level} reveal a remainder of electrons trapped in high-k bulk shallow traps.

Wet motor geroter fuel pump

Energy Technology Data Exchange (ETDEWEB)

Wiernicki, M.V.

1987-05-05

This patent describes a wet motor gerotor fuel pump for pumping fuel from a fuel source to an internal combustion which consists of: gerotor pump means comprising an inner pump gear, an outer pump gear, and second tang means located on one of the inner and outer pump gears. The second tang means further extends in a second radial direction radially offset from the first radial direction and forms a driving connection with the first tang means such that the fuel pump pumps fuel from the fuel source into the narrow conduit inlet chamber, through the gerotor pump means past the electric motor means into the outlet housing means substantially along the flow axis to the internal combustion engine.

Pump failure leads to alternative vertical pump condition monitoring technique

International Nuclear Information System (INIS)

DeVilliers, Adriaan; Glandon, Kevin

2011-01-01

Condition monitoring and detecting early signs of potential failure mechanisms present particular problems in vertical pumps. Most often, the majority of the pump assembly is not readily accessible for visual or audible inspection or conventional vibration monitoring techniques using accelerometers and/or proximity sensors. The root cause failure analysis of a 2-stage vertical centrifugal service-water pump at a nuclear power generating facility in the USA is presented, highlighting this long standing challenge in condition monitoring of vertical pumps. This paper will summarize the major findings of the root cause analysis (RCA), highlight the limitations of traditional monitoring techniques, and present an expanded application of motor current monitoring as a means to gain insight into the mechanical performance and condition of a pump. The 'real-world' example of failure, monitoring and correlation of the monitoring technique to a detailed pump disassembly inspection is also presented. This paper will explain some of the reasons behind well known design principles requiring natural frequency separation from known forcing frequencies, as well as explore an unexpected submerged brittle fracture failure mechanism, and how such issues may be avoided. (author)

Diode-pumped laser with improved pumping system

Science.gov (United States)

Chang, Jim J.

2004-03-09

A laser wherein pump radiation from laser diodes is delivered to a pump chamber and into the lasing medium by quasi-three-dimensional compound parabolic concentrator light channels. The light channels have reflective side walls with a curved surface and reflective end walls with a curved surface. A flow tube between the lasing medium and the light channel has a roughened surface.

Ouabain affinity determining residues lie close to the Na/K pump ion pathway.

Science.gov (United States)

Artigas, Pablo; Gadsby, David C

2006-08-15

The Na/K pump establishes essential ion concentration gradients across animal cell membranes. Cardiotonic steroids, such as ouabain, are specific inhibitors of the Na/K pump. We exploited the marine toxin, palytoxin, to probe both the ion translocation pathway through the Na/K pump and the site of its interaction with ouabain. Palytoxin uncouples the pump's gates, which normally open strictly alternately, thus allowing both gates to sometimes be open, so transforming the pump into an ion channel. Palytoxin therefore permits electrophysiological analysis of even a single Na/K pump. We used outside-out patch recording of Xenopus alpha1beta3 Na/K pumps, which were made ouabain-resistant by point mutation, after expressing them in Xenopus oocytes. Endogenous, ouabain-sensitive, Xenopus alpha1beta3 Na/K pumps were silenced by continuous exposure to ouabain. We found that side-chain charge of two residues at either end of the alpha subunit's first extracellular loop, known to make a major contribution to ouabain affinity, strongly influenced conductance of single palytoxin-bound pump-channels by an electrostatic mechanism. The effects were mimicked by modification of cysteines introduced at those two positions with variously charged methanethiosulfonate reagents. The consequences of these modifications demonstrate that both residues lie in a wide vestibule near the mouth of the pump's ion pathway. Bound ouabain protects the site with the strongest influence on conductance from methanethiosulfonate modification, while leaving the site with the weaker influence unprotected. The results suggest a method for mapping the footprint of bound cardiotonic steroid on the extracellular surface of the Na/K pump.

Optically pumped atoms

CERN Document Server

Happer, William; Walker, Thad

2010-01-01

Covering the most important knowledge on optical pumping of atoms, this ready reference is backed by numerous examples of modelling computation for optical pumped systems. The authors show for the first time that modern scientific computing software makes it practical to analyze the full, multilevel system of optically pumped atoms. To make the discussion less abstract, the authors have illustrated key points with sections of MATLAB codes. To make most effective use of contemporary mathematical software, it is especially useful to analyze optical pumping situations in the Liouville spa

Outcome of Cardiac Rehabilitation Following Off-Pump Versus On-Pump Coronary Bypass Surgery

Directory of Open Access Journals (Sweden)

Reza Arefizadeh

2017-05-01

CONCLUSIONS: Regarding QOL and psychological status, there were no differences in the CR outcome between those who underwent off-pump bypass surgery and those who underwent on-pump surgery; nevertheless, the off-pump technique was superior to the on-pump method on METs improvement following CR.

Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Hunt, A. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States); Easley, S. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States)

2012-05-01

This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

Interaction of antibacterial compounds with RND efflux pumps in Pseudomonas aeruginosa

Directory of Open Access Journals (Sweden)

Juerg eDreier

2015-07-01

Full Text Available Pseudomonas aeruginosa infections are becoming increasingly difficult to treat due to intrinsic antibiotic resistance and the propensity of this pathogen to accumulate diverse resistance mechanisms. Hyperexpression of efflux pumps of the Resistance-Nodulation-Division-type multidrug efflux pumps (e.g. MexAB-OprM, chromosomally encoded by mexAB-oprM, mexCD-oprJ, mexEF-oprN, and mexXY (-oprA is often detected in clinical isolates and contributes to worrying multi-drug resistance phenotypes.Not all antibiotics are affected to the same extent by the aforementioned RND efflux pumps. The impact of efflux on antibiotic activity varies not only between different classes of antibiotics but also between members of the same family of antibiotics. Subtle differences in physicochemical features of compound-pump and compound-solvent interactions largely determine how compounds are affected by efflux activity.The combination of different high-resolution techniques helps to gain insight into the functioning of these molecular machineries. This review discusses substrate recognition patterns based on experimental evidence and computer simulations with a focus on MexB, the pump subunit of the main RND transporter in P. aeruginosa.

Pumps for nuclear facilities

International Nuclear Information System (INIS)

1999-01-01

The guide describes how the Finnish Radiation and Nuclear Safety Authority (STUK) controls pumps and their motors at nuclear power plants and other nuclear facilities. The scope of the control is determined by the Safety Class of the pump in question. The various phases of the control are: (1) review of construction plan, (2) control of manufacturing, and construction inspection, (3) commissioning inspection, and (4) control during operation. STUK controls Safety Class 1, 2 and 3 pumps at nuclear facilities as described in this guide. STUK inspects Class EYT (non-nuclear) pumps separately or in connection with the commissioning inspections of the systems. This guide gives the control procedure and related requirements primarily for centrifugal pumps. However, it is also applied to the control of piston pumps and other pump types not mentioned in this guide

Effects of changes in pumping on regional groundwater-flow paths, 2005 and 2010, and areas contributing recharge to discharging wells, 1990–2010, in the vicinity of North Penn Area 7 Superfund site, Montgomery County, Pennsylvania

Science.gov (United States)

Senior, Lisa A.; Goode, Daniel J.

2017-06-06

A previously developed regional groundwater flow model was used to simulate the effects of changes in pumping rates on groundwater-flow paths and extent of recharge discharging to wells for a contaminated fractured bedrock aquifer in southeastern Pennsylvania. Groundwater in the vicinity of the North Penn Area 7 Superfund site, Montgomery County, Pennsylvania, was found to be contaminated with organic compounds, such as trichloroethylene (TCE), in 1979. At the time contamination was discovered, groundwater from the underlying fractured bedrock (shale) aquifer was the main source of supply for public drinking water and industrial use. As part of technical support to the U.S. Environmental Protection Agency (EPA) during the Remedial Investigation of the North Penn Area 7 Superfund site from 2000 to 2005, the U.S. Geological Survey (USGS) developed a model of regional groundwater flow to describe changes in groundwater flow and contaminant directions as a result of changes in pumping. Subsequently, large decreases in TCE concentrations (as much as 400 micrograms per liter) were measured in groundwater samples collected by the EPA from selected wells in 2010 compared to 2005‒06 concentrations.To provide insight on the fate of potentially contaminated groundwater during the period of generally decreasing pumping rates from 1990 to 2010, steady-state simulations were run using the previously developed groundwater-flow model for two conditions prior to extensive remediation, 1990 and 2000, two conditions subsequent to some remediation 2005 and 2010, and a No Pumping case, representing pre-development or cessation of pumping conditions. The model was used to (1) quantify the amount of recharge, including potentially contaminated recharge from sources near the land surface, that discharged to wells or streams and (2) delineate the areas contributing recharge that discharged to wells or streams for the five conditions.In all simulations, groundwater divides differed from

Successful energy transition in Germany by pumped storage expansion; Energiewende erfolgreich gestalten durch Pumpspeicherausbau

Energy Technology Data Exchange (ETDEWEB)

Krueger, Klaus [Voith Hydro Holding GmbH und Co. KG, Heidenheim (Germany). FuE; Rotering, Niklas [RWTH Aachen Univ. (Germany). Forschungsgruppe Versorgungsqualitaet und Regulierung

2014-11-01

Operational flexibility in electrical energy generation and consumption as well as the provision of reliable and available capacity are two major challenges of the German energy transition ('Energiewende'). The consistent deployment of cost-effective and proven pumped storage technology can provide significant contributions to meet both challenges. This paper shows that an expansion of pumped storage plants as part of the energy transition is a technically and macro-economically interesting option for Germany. Pumped storage plants compensate the volatility of renewables and enable gentle and economically efficient operation of the remaining thermal power plant fleet.

Detection of pump degradation

International Nuclear Information System (INIS)

Greene, R.H.; Casada, D.A.; Ayers, C.W.

1995-08-01

This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented

Detection of pump degradation

Energy Technology Data Exchange (ETDEWEB)

Greene, R.H.; Casada, D.A.; Ayers, C.W. [and others

1995-08-01

This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

Survey of pumps for tritium gas

International Nuclear Information System (INIS)

Dowell, T.M.

1983-05-01

This report considers many different types of pumps for their possible use in pumping tritium gas in the low, intermediate and high vacuum ranges. No one type of pump is suitable for use over the wide range of pumping pressure required in a typical pumping system. The favoured components for such a system are: bellows pump (low vacuum); orbiting scroll pump (intermediate vacuum); magnetically suspended turbomolecular pump (high vacuum); cryopump (high vacuum). Other pumps which should be considered for possible future development are: mound modified vane pump; SRTI wobble pump; roots pump with canned motor. It is proposed that a study be made of a future tritium pumping system in a Canadian tritium facility, e.g. a tritium laboratory

Air-source heat pump carbon footprints: HFC impacts and comparison to other heat sources

International Nuclear Information System (INIS)

Johnson, Eric P.

2011-01-01

European governments see that heat pumps could reduce carbon emissions in space- and hot-water heating. EU's Renewable Energy Directive designates heat pumps as renewable - eligible for various subsidies - if their carbon footprints are below an implied, average threshold. This threshold omits carbon generated by manufacture and emission of a heat-pump's fluorocarbon refrigerant. It also omits the footprint of the heat pump's hardware. To see if these omissions are significant, this study calculated carbon footprints of representative, residential heat pumps in the UK. Three findings emerged. First, in relation to power generation, which accounts for most of a heat-pump's greenhouse-gas emissions, fluorocarbons add another 20% to the footprint. Second, at UK efficiencies a heat-pump footprint (in kg CO 2 e emitted per kWh delivered) is comparable or higher than footprints of gaseous fuels used in heating. It is lower than the footprint of heating oil and far lower than the footprints of solid fuels. Third, production and disposal of a heat pump's hardware is relatively insignificant, accounting for only 2-3% of the overall heat-pump footprint. Sensitivities to the results were assessed: key factors are footprint of electricity generation, F-gas composition and leak rates and type of wall construction. - Research highlights: → Refrigerant emissions add 20% to a UK air-source heat pump's carbon footprint. → This contribution is so far ignored by regulations. → UK heat pump footprints are comparable to those of gaseous fuels.

Vertical pump assembly

International Nuclear Information System (INIS)

Dohnal, M.; Rosel, J.; Skarka, V.

1988-01-01

The mounting is described of the drive assembly of a vertical pump for nuclear power plants in areas with seismic risk. The assembly is attached to the building floor using flexible and damping elements. The design allows producing seismically resistant pumps without major design changes in the existing types of vertical pumps. (E.S.). 1 fig

Normetex Pump Alternatives Study

International Nuclear Information System (INIS)

Clark, Elliot A.

2013-01-01

A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

Performance of Wind Pump Prototype

African Journals Online (AJOL)

Mulu

Mekelle University, Mekelle, Ethiopia (*mul_at@yahoo.com). ABSTRACT. A wind ... balanced rotor power and reciprocating pump, hence did not consider the effect of pump size. ... Keywords: Wind pump, Windmill, Performance testing, Pump efficiency, Pump discharge, ... Unfortunately, in rural places, where the houses are.

Development of model pump for establishing hydraulic design of primary sodium pumps in PFBR

International Nuclear Information System (INIS)

Chougule, R.J.; Sahasrabudhe, H.G.; Rao, A.S.L.K.; Balchander, K.; Kale, R.D.

1994-01-01

Indira Gandhi Centre for Atomic Research, Kalpakkam indicated requirement of indigenous development of primary sodium pump, handling liquid sodium as coolant in Fast Breeder Reactor. The primary sodium pump concept selected in its preliminary design is a vertical, single stage, with single suction impeller, suction facing downwards. The pump is having diffuser, discharge casing and discharge collector. The 1/3 rd size model pump is developed to establish the hydraulic performance of the prototype primary sodium pump. The main objectives were to verify the hydraulic design to operate on low net positive suction head available (NPSHA), no evidence of visible cavitation at available NPSHA, the pump should be designed with a diffuser etc. The model pump PSP 250/40 was designed and successfully developed by Research and Development Division of M/s Kirloskar Brothers Ltd., Kirloskarvadi. The performance testing using model pump was successfully carried out on a closed circuit test rig. The performance of a model pump at three different speeds 1900 rpm, 1456 rpm and 975 rpm was established. The values of hydraulic axial thrust with and without balancing holes on impeller at 1900 rpm was measured. Visual cavitation study at 1900 rpm was carried out to establish the NPSH at bubble free operation of the pump. The tested performance of the model pump is converted to the full scale prototype pump. The predicted performance of prototype pump at 700 rpm was found to be meeting fully with the expected duties. (author). 6 figs., 3 tabs

Solar Pumping : The Basics

OpenAIRE

World Bank Group

2018-01-01

Solar photovoltaic water pumping (SWP) uses energy from solar photovoltaic (PV) panels to power an electric water pump. The entire process, from sunlight to stored energy, is elegant and simple. Over last seven years, the technology and price of solar pumping have evolved dramatically and hence the opportunities it presents. Solar pumping is most competitive in regions with high solar inso...

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

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.

Off-pump versus on-pump coronary artery bypass grafting for ischaemic heart disease

DEFF Research Database (Denmark)

Møller, Christian H; Penninga, Luit; Wetterslev, Jørn

2012-01-01

Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear.......Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear....

Experimental and numerical investigation of centrifugal pumps with asymmetric inflow conditions

Science.gov (United States)

Mittag, Sten; Gabi, Martin

2015-11-01

Most of the times pumps operate off best point states. Reasons are changes of operating conditions, modifications, pollution and wearout or erosion. As consequences non-rotational symmetric flows, transient operational conditions, increased risk of cavitation, decrease of efficiency and unpredictable wearout can appear. Especially construction components of centrifugal pumps, in particular intake elbows, contribute to this matter. Intake elbows causes additional losses and secondary flows, hence non-rotational velocity distributions as intake profile to the centrifugal pump. As a result the impeller vanes experience permanent changes of the intake flow angle and with it transient flow conditions in the blade channels. This paper presents the first results of a project, experimentally and numerically investigating the consequences of non-rotational inflow to leading edge flow conditions of a centrifugal pump. Therefore two pumpintake- elbow systems are compared, by only altering the intake elbow geometry: a common single bended 90° elbow and a numerically optimized elbow (improved regarding rotational symmetric inflow conditions and friction coefficient). The experiments are carried out, using time resolved stereoscopic PIV on a full acrylic pump with refractions index matched (RIM) working fluid. This allows transient investigations of the flow field simultaneously for all blade leading edges. Additional CFD results are validated and used to further support the investigation i.e. for comparing an analog pump system with ideal inflow conditions.

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.

Pumps in nuclear power plants

International Nuclear Information System (INIS)

Kim, J.H.

1991-01-01

This paper reports that pumps play an important role in nuclear plant operation. For instance, reactor coolant pumps (RCPs) should provide adequate cooling for reactor core in both normal operation and transient or accident conditions. Pumps such as Low Pressure Safety Injection (LPSI) pump in the Emergency Core Cooling System (ECCS) play a crucial role during an accident, and their reliability is of paramount importance. Some key issues involved with pumps in nuclear plant system include the performance of RCP under two-phase flow conditions, piping vibration due to pump operating in two-phase flows, and reliability of LPSI pumps

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

1 Hz fast-heating fusion driver HAMA pumped by a 10 J green diode-pumped solid-state laser

International Nuclear Information System (INIS)

Mori, Y.; Komeda, O.; Nakayama, S.; Ishii, K.; Hanayama, R.; Fujita, K.; Okihara, S.; Sekine, T.; Satoh, N.; Kurita, T.; Kawashima, T.; Kan, H.; Nakamura, N.; Kondo, T.; Fujine, M.; Azuma, H.; Hioki, T.; Kakeno, M.; Motohiro, T.; Nishimura, Y.

2013-01-01

A Ti : sapphire laser HAMA pumped by a diode-pumped solid-state laser (DPSSL) is developed to enable a high-repetitive inertial confinement fusion (ICF) experiment to be conducted. To demonstrate a counter-irradiation fast-heating fusion scheme, a 3.8 J, 0.4 ns amplified chirped pulse is divided into four beams: two counter-irradiate a target with intensities of 6 × 10 13 W cm −2 , and the remaining two are pulse-compressed to 110 fs for heating the imploded target with intensities of 2 × 10 17 W cm −2 . HAMA contributed to the first demonstration by showing that a 10 J class DPSSL is adaptable to ICF experiments and succeeded in DD neutron generation in the repetition mode. Based on HAMA, we can design and develop an integrated repetitive ICF experiment machine by including target injection and tracking. (paper)

Impulse pumping modelling and simulation

International Nuclear Information System (INIS)

Pierre, B; Gudmundsson, J S

2010-01-01

Impulse pumping is a new pumping method based on propagation of pressure waves. Of particular interest is the application of impulse pumping to artificial lift situations, where fluid is transported from wellbore to wellhead using pressure waves generated at wellhead. The motor driven element of an impulse pumping apparatus is therefore located at wellhead and can be separated from the flowline. Thus operation and maintenance of an impulse pump are facilitated. The paper describes the different elements of an impulse pumping apparatus, reviews the physical principles and details the modelling of the novel pumping method. Results from numerical simulations of propagation of pressure waves in water-filled pipelines are then presented for illustrating impulse pumping physical principles, and validating the described modelling with experimental data.

Reactor recirculation pump test loop

International Nuclear Information System (INIS)

Taka, Shusei; Kato, Hiroyuki

1979-01-01

A test loop for a reactor primary loop recirculation pumps (PLR pumps) has been constructed at Ebara's Haneda Plant in preparation for production of PLR pumps under license from Byron Jackson Pump Division of Borg-Warner Corporation. This loop can simulate operating conditions for test PLR pumps with 130 per cent of the capacity of pumps for a 1100 MWe BWR plant. A main loop, primary cooling system, water demineralizer, secondary cooling system, instrumentation and control equipment and an electric power supply system make up the test loop. This article describes the test loop itself and test results of two PLR pumps for Fukushima No. 2 N.P.S. Unit 1 and one main circulation pump for HAZ Demonstration Test Facility. (author)

33 CFR 157.126 - Pumps.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Pumps. 157.126 Section 157.126... Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.126 Pumps. (a) Crude oil must be supplied to the COW machines by COW system pumps or cargo pumps. (b) The pumps under paragraph...

Pump safety device

International Nuclear Information System (INIS)

Timmermans, Francis; Vandervorst, Jean.

1981-01-01

Safety device for longitudinally leak proofing the shaft of a pump in the event of the fracture of the dynamic seal separating the pump fluid high pressure chamber from the low pressure chamber. It is designed for fitting to the primary pumps of nuclear reactors. It includes a hollow cyclindrical piston located coaxially around the pump shaft and normally housed in a chamber provided for this purpose in the fixed housing of the dynamic seal, and means for moving this piston coaxially so as to compress a safety O ring between the shaft and the piston in the event of the dynamic seal failing [fr

Detection of pump degradation

International Nuclear Information System (INIS)

Casada, D.A.

1994-01-01

There are a variety of stressors that can affect the operation of centrifugal pumps. These can generally be classified as: Mechanical; Hydraulic; Tribological; Chemical; and Other (including those associated with the pump driver). 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

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

Na+/K+ pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches

Science.gov (United States)

Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

2016-01-01

The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na+/K+ pump current to such bursting activity has not been well studied. We used monensin, a Na+/H+ antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs+. The decreased period could also occur if the pump was inhibited with strophanthidin or K+-free saline. Our monensin results were reproduced in model, which explains the pump’s contributions to bursting activity based on Na+ dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks. DOI: http://dx.doi.org/10.7554/eLife.19322.001 PMID:27588351

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.)

46 CFR 154.1135 - Pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Pumps. 154.1135 Section 154.1135 Shipping COAST GUARD... Pumps. (a) Water to the water spray system must be supplied by: (1) A pump that is only for the use of the system; (2) A fire pump; or (3) A pump specially approved by the Commandant (CG-522). (b...

Efficiency optimization of a photovoltaic water pumping system for irrigation in Ouargla, Algeria

Science.gov (United States)

Louazene, M. L.; Garcia, M. C. Alonso; Korichi, D.

2017-02-01

This work is technical study to contribute to the optimization of pumping systems powered by solar energy (clean) and used in the field of agriculture. To achieve our goals, we studied the techniques that must be entered on a photovoltaic system for maximum energy from solar panels. Our scientific contribution in this research is the realization of an efficient photovoltaic pumping system for irrigation needs. To achieve this and extract maximum power from the PV generator, two axes have been optimized: 1. Increase in the uptake of solar radiation by choice an optimum tilt angle of the solar panels, and 2. it is necessary to add an adaptation device, MPPT controller with a DC-DC converter, between the source and the load.

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.

Root cause analysis of pump valve failures of three membrane pump systems

NARCIS (Netherlands)

Buijs, L.J.; Eijk, A.; Hooft, L. van

2014-01-01

This paper will present the root cause analysis and the solution of fatigue failures of the pump valves of three membrane pump systems installed on a chemical plant of Momentive in Pernis, the Netherlands. The membrane pumps were installed approximately 30 years ago. Each system has encountered

Pump audit identifies the energy consumers; Pump Audit identifiziert gezielt die Energieverschwender

Energy Technology Data Exchange (ETDEWEB)

Siekemann, Ralf [Grundfos GmbH, Erkrath (Germany)

2011-03-14

Engineering and services, which enhance and secure the energy efficiency of pump systems, are demanded. Speed-regulated pumps, included high efficient motors and a service philosophy, be designed on value conservation and cost control, are as well as professional ''pump-audits''. (orig./GL)

Auto-control of pumping operations in sewerage systems by rule-based fuzzy neural networks

Directory of Open Access Journals (Sweden)

Y.-M. Chiang

2011-01-01

Full Text Available Pumping stations play an important role in flood mitigation in metropolitan areas. The existing sewerage systems, however, are facing a great challenge of fast rising peak flow resulting from urbanization and climate change. It is imperative to construct an efficient and accurate operating prediction model for pumping stations to simulate the drainage mechanism for discharging the rainwater in advance. In this study, we propose two rule-based fuzzy neural networks, adaptive neuro-fuzzy inference system (ANFIS and counterpropagation fuzzy neural network for on-line predicting of the number of open and closed pumps of a pivotal pumping station in Taipei city up to a lead time of 20 min. The performance of ANFIS outperforms that of CFNN in terms of model efficiency, accuracy, and correctness. Furthermore, the results not only show the predictive water levels do contribute to the successfully operating pumping stations but also demonstrate the applicability and reliability of ANFIS in automatically controlling the urban sewerage systems.

Pump polarization insensitive and efficient laser-diode pumped Yb:KYW ultrafast oscillator.

Science.gov (United States)

Wang, Sha; Wang, Yan-Biao; Feng, Guo-Ying; Zhou, Shou-Huan

2016-02-01

We theoretically and experimentally report and evaluate a novel split laser-diode (LD) double-end pumped Yb:KYW ultrafast oscillator aimed at improving the performance of an ultrafast laser. Compared to a conventional unpolarized single-LD end-pumped ultrafast laser system, we improve the laser performance such as absorption efficiency, slope efficiency, cw mode-locking threshold, and output power by this new structure LD-pumped Yb:KYW ultrafast laser. Experiments were carried out with a 1 W output fiber-coupled LD. Experimental results show that the absorption increases from 38.7% to 48.4%, laser slope efficiency increases from 18.3% to 24.2%, cw mode-locking threshold decreases 12.7% from 630 to 550 mW in cw mode-locking threshold, and maximum output-power increases 28.5% from 158.4 to 221.5 mW when we switch the pump scheme from an unpolarized single-end pumping structure to a split LD double-end pumping structure.

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)

Development of heat pump technology in eco-energy city project

Energy Technology Data Exchange (ETDEWEB)

Omata, Tomio [New Energy Development Organization (Japan); Ogisu, Yoshihiro [Office of Eco-Energy City Project, Energy Conservation Center (Japan)

1999-07-01

In the New Sunshine Project conducted by MITI Japan, Eco-Energy City-Project covers the research area of utilization of industrial and municipal waste heat. For the further utilization of waste heat, several research programs are carried out for recovery and conversion of waste heat, transportation and storage of waste heat and final use of rather low temperature heat transported. Various types of heat driven heat pumps are developed in the Eco-Energy City Project. Concept of the Project is to utilize industrial and municipal waste heat for the city where energy demand is increasing. These heat pumps will contribute for the reduction of CO{sub 2} emission. (orig.)

Analysis of data from water lift powered by solar energy pump

Energy Technology Data Exchange (ETDEWEB)

Oyama, Paulo Takashi [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil); Ricieri, Reinaldo Prandini [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil). Dept. de Engenharia Agricola], E-mail: ricieri@unioeste.br; Halmeman, Maria Cristina Rodrigues [Universidade Estadual Paulista (UNESP), Botucatu, SP (Brazil); Gnoatto, Estor; Kavanagh; Brenneisen, Paulo Job [Universidade Tecnologica Federal do Parana (UTFPR), Medianeira, PR (Brazil)], Emails: gnoatto@utfpr.edu.br, kavanagh@utfpr.edu.br, brenneisen@utfpr.edu.br

2008-07-01

Due to the high costs to install electricity in remote locations, away from the regular urban electrical installations, photovoltaic solar energy has ample application in public illumination, water pumping, health services offices, etc. With the purpose to contribute to a better use of this kind of energy, this project aimed in analyzing the outflow and efficiency of a motor pump powered by photovoltaic panels, the irradiation necessary to activate it for water lift, collecting data at every 6- meter height, ranging from 6,2 to 18,2 meters. This study is part of a development project of the Universidade Tecnologica Federal do Parana (UTFPR), by making use of photovoltaic panels, motor pump, pyranometers, thermocouple type K, pressure transducer and outflow transducer. The data show a maximum average outflow of 584,299 Lh{sup -1} and maximum efficiency of 23,338% for a lift of 18,2 m. There is also the need of irradiation for the activation of the motor pump proportional to the height of the lift, in a polynomial dependence of the third order. (author)

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

Pumping slots: impedances and power losses

Energy Technology Data Exchange (ETDEWEB)

Kurennoy, S [Maryland Univ., College Park, MD (United States). Dept. of Physics

1996-08-01

Contributions of pumping slots to the beam coupling impedances and power losses in a B-factory ring are considered. While their leading contribution is to the inductive impedance, for high-intensity machines with short bunches like e{sup +}e{sup -} B-factories the real part of the impedance and related loss factors are also important. Using an analytical approach we calculate the coupling impedances and loss factors due to slots in a ring with an arbitrary cross section of the vacuum chamber. Effects of the slot tilt on the beam impedance are also considered, and restrictions on the tilt angle are derived from limitations on the impedance increase. The power leakage through the slots is discussed briefly. The results are applied to the KEK B-factory. (author)

Circulation pump mounting

International Nuclear Information System (INIS)

Skalicky, A.

1976-01-01

The suspension is described of nuclear reactor circulating pumps enabling their dilatation with a minimum reverse force consisting of spacing rods supported with one end in the anchor joints and provided with springs and screw joints engaging the circulating pump shoes. The spacing rods are equipped with side vibration dampers anchored in the shaft side wall and on the body of the circulating pump drive body. The negative reverse force F of the spacing rods is given by the relation F=Q/l.y, where Q is the weight of the circulating pump, l is the spatial distance between the shoe joints and anchor joints, and y is the deflection of the circulating pump vertical axis from the mean equilibrium position. The described suspension is advantageous in that that the reverse force for the deflection from the mean equilibrium position is minimal, dynamic behaviour is better, and construction costs are lower compared to suspension design used so far. (J.B.)

Off-pump Coronary Artery Bypass Graft in a High Risk Patient ...

African Journals Online (AJOL)

On-pump coronary artery bypass graft (CABG) entails the use of cardiopulmonary bypass (CPB). The procedure is safe but it's not without complications like neurocognitive deficits, cerebrovascular accidents, myocardial ischemic injury and activation of inflammatory pathways that contribute to pulmonary, renal, hematologic ...

Detection of pump degradation

International Nuclear Information System (INIS)

Casada, D.

1994-01-01

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 spectral 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. 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

Tokamak pump limiters

International Nuclear Information System (INIS)

Conn, R.W.

1984-05-01

Recent experiments with a scoop limiter without active internal pumping have been carried out in the PDX tokamak with up to 6MW of auxiliary neutral beam heating. Experiments have also been done with a rotating head pump limiter in the PLT tokamak in conjunction with RF plasma heating. Extensive experiments have been done in the ISX-B tokamak and first experiments have been completed with the ALT-I limiter in TEXTOR. The pump limiter modules in these latter two machines have internal getter pumping. Experiments in ISX-B are with ohmic and auxiliary neutral beam heating. The results in ISX-B and TEXTOR show that active density control and particle removal is achieved with pump limiters. In ISX-B, the boundary layer (or scape-off layer) plasma partially screens the core plasma from gas injection. In both ISX-B and TEXTOR, the pressure internal to the module scales linearly with plasma density but in ISX-B, with neutral beam injection, a nonlinear increase is observed at the highest densities studied. Plasma plugging is the suspected cause. Results from PDX suggest that a region may exist in which core plasma energy confinement improves using a pump limiter during neutral beam injection. Asymmetric radial profiles and an increased edge electron temperature are observed in discharges with improved confinement. The injection of small amounts of neon into ISX-B has more clearly shown an improved electron core energy confinement during neutral beam injection. While carried out with a regular limiter, this Z-mode of operation is ideal for use with pump limiters and should be a way to achieve energy confinement times similar to values for H-mode tokamak plasmas. The implication of all these results for the design of a reactor pump limiter is described

Tokamak pump limiters

International Nuclear Information System (INIS)

Conn, R.W.; California Univ., Los Angeles

1984-01-01

Recent experiments with a scoop limiter without active internal pumping have been carried out in the PDX tokamak with up to 6 MW of auxiliary neutral beam heating. Experiments have also been performed with a rotating head pump limiter in the PLT tokamak in conjunction with RF plasma heating. Extensive experiments have been done in the ISX-B tokamak and first experiments have been completed with the ALT-I limiter in TEXTOR. The pump limiter modules in these latter two machines have internal getter pumping. Experiments in ISX-B are with ohmic and auxiliary neutral beam heating. The results in ISX-B and TEXTOR show that active density control and particle removal is achieved with pump limiters. In ISX-B, the boundary layer (or scrape-off layer) plasma partially screens the core plasma from gas injection. In both ISX-B and TEXTOR, the pressure internal to the module scales linearly with plasma density but in ISX-B, with neutral beam injection, a nonlinear increase is observed at the highest densities studied. Plasma plugging is the suspected cause. Results from PDX suggest that a regime may exist in which core plasma energy confinement improves using a pump limiter during neutral beam injection. Asymmetric radial profiles and an increased edge electron temperature are observed in discharges with improved confinement. The injection of small amounts of neon into ISX-B has more clearly shown an improved electron core energy confinement during neutral beam injection. While carried out with a regular limiter, this 'Z-mode' of operation is ideal for use with pump limiters and should be a way to achieve energy confinement times similar to values for H-mode tokamak plasmas. The implication of all these results for the design of a reactor pump limiter is described. (orig.)

Jet pump assisted artery

Science.gov (United States)

1975-01-01

A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

GAS METERING PUMP

Science.gov (United States)

George, C.M.

1957-12-31

A liquid piston gas pump is described, capable of pumping minute amounts of gas in accurately measurable quantities. The pump consists of a flanged cylindrical regulating chamber and a mercury filled bellows. Sealed to the ABSTRACTS regulating chamber is a value and having a gas inlet and outlet, the inlet being connected by a helical channel to the bellows. A gravity check valve is in the gas outlet, so the gas passes through the inlet and the helical channel to the bellows where the pumping action as well as the metering is accomplished by the actuation of the mercury filled bellows. The gas then flows through the check valve and outlet to any associated apparatus.

Inservice testing of vertical pumps

International Nuclear Information System (INIS)

Cornman, R.E. Jr.; Schumann, K.E.

1994-01-01

This paper focuses on the problems that may occur with vertical pumps while inservice tests are conducted in accordance with existing American Society of Mechanical Engineers Code, Section XI, standards. The vertical pump types discussed include single stage, multistage, free surface, and canned mixed flow pumps. Primary emphasis is placed on the hydraulic performance of the pump and the internal and external factors to the pump that impact hydraulic performance. In addition, the paper considers the mechanical design features that can affect the mechanical performance of vertical pumps. The conclusion shows how two recommended changes in the Code standards may increase the quality of the pump's operational readiness assessment during its service life

Effect of diabetes on the ion pumps of the bladder.

Science.gov (United States)

Mustafa, Seham

2013-01-01

To establish whether the activities of Na+/K+-adenosine triphosphatase (ATPase) and Ca2+-ATPases ion pumps in bladder smooth muscle are altered as a consequence of diabetes and, if so, how this might contribute to bladder cystopathy. Urinary bladder dysfunction is a common occurrence in patients with diabetes. Pressure generation requires calcium and cytosolic ATP. Activities of these pumps are responsible for calcium homeostasis. Rat urinary detrusor muscle strips were suspended in organ baths containing Krebs solution for isometric tension recording. Tissue responses to the Na+/K+-ATPase pump inhibitor, ouabain, the plasma membrane Ca2+ ATPase inhibitor, vanadate, and the sarcoplasmic reticulum Ca2+ ATPase inhibitor, cyclopiazonic acid (CPA), were examined from normal and streptozocin-induced diabetic rats for 2, 4, and 12 weeks. Ouabain, vanadate, and CPA caused concentration-dependent contractions of bladder strips from diabetic and normal rats. The degree of contraction of diabetic bladder muscle was lower than that of controls. This reduction was a function of duration of diabetes. For ouabain, the reduction peaked at 2 weeks, with partial restoration to normal after diabetes induction. For vanadate and CPA, the reduction increased with the duration of diabetes. The ion pumps are important modulators of bladder smooth muscle tone, and in a rat model of streptozotocin-induced diabetes, the activity of these pumps is impaired. Although this is only a single model of diabetes, these findings suggest that a defect in these pumps may be an important component of the development of diabetic bladder cystopathy. Copyright © 2013 Elsevier Inc. All rights reserved.

Interaction of antibacterial compounds with RND efflux pumps in Pseudomonas aeruginosa

Science.gov (United States)

Dreier, Jürg; Ruggerone, Paolo

2015-01-01

Pseudomonas aeruginosa infections are becoming increasingly difficult to treat due to intrinsic antibiotic resistance and the propensity of this pathogen to accumulate diverse resistance mechanisms. Hyperexpression of efflux pumps of the Resistance-Nodulation-Cell Division (RND)-type multidrug efflux pumps (e.g., MexAB-OprM), chromosomally encoded by mexAB-oprM, mexCD-oprJ, mexEF-oprN, and mexXY (-oprA) is often detected in clinical isolates and contributes to worrying multi-drug resistance phenotypes. Not all antibiotics are affected to the same extent by the aforementioned RND efflux pumps. The impact of efflux on antibiotic activity varies not only between different classes of antibiotics but also between members of the same family of antibiotics. Subtle differences in physicochemical features of compound-pump and compound-solvent interactions largely determine how compounds are affected by efflux activity. The combination of different high-resolution techniques helps to gain insight into the functioning of these molecular machineries. This review discusses substrate recognition patterns based on experimental evidence and computer simulations with a focus on MexB, the pump subunit of the main RND transporter in P. aeruginosa. PMID:26217310

Vacuum pumping for controlled thermonuclear reactors

International Nuclear Information System (INIS)

Watson, J.S.; Fisher, P.W.

1976-01-01

Thermonuclear reactors impose unique vacuum pumping problems involving very high pumping speeds, handling of hazardous materials (tritium), extreme cleanliness requirements, and quantitative recovery of pumped materials. Two principal pumping systems are required for a fusion reactor, a main vacuum system for evacuating the torus and a vacuum system for removing unaccelerated deuterium from neutral beam injectors. The first system must pump hydrogen isotopes and helium while the neutral beam system can operate by pumping only hydrogen isotopes (perhaps only deuterium). The most promising pumping techniques for both systems appear to be cryopumps, but different cryopumping techniques can be considered for each system. The main vacuum system will have to include cryosorption pumps cooled to 4.2 0 K to pump helium, but the unburned deuterium-tritium and other impurities could be pumped with cryocondensation panels (4.2 0 K) or cryosorption panels at higher temperatures. Since pumping speeds will be limited by conductance through the ducts and thermal shields, the pumping performance for both systems will be similar, and other factors such as refrigeration costs are likely to determine the choice. The vacuum pumping system for neutral beam injectors probably will not need to pump helium, and either condensation or higher temperature sorption pumps can be used

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.

Pump system characterization and reliability enhancement

International Nuclear Information System (INIS)

Staunton, R.H.

1998-01-01

Pump characterization studies were performed at the Oak Ridge National Laboratory (ORNL) to review and analyze six years (1990-1995) of data from pump systems at domestic nuclear plants. The studies considered not only pumps and pump motors but also pump-related circuit breakers and turbine drives (i.e., the pump system). One significant finding was that the number of 'significant' failures of the pump circuit breaker exceeds the number of significant failures of the pump itself. The study also shows how regulatory code testing was designed for the pump only and therefore did not lead to the discovery of other significant pump system failures. Potential diagnostic technologies, both experimental and mature, suitable for on-line and off-line pump testing were identified. The study does not select or recommend technologies but proposes diagnostic technologies and monitoring techniques that should be further evaluated/developed for making meaningful and critically-needed improvements in the reliability of the pump system. (author)

Life cycle assessment of domestic heat pump hot water systems in Australia

Directory of Open Access Journals (Sweden)

Moore Andrew D.

2017-01-01

Full Text Available Water heating accounts for 23% of residential energy consumption in Australia, and, as over half is provided by electric water heaters, is a significant source of greenhouse gas emissions. Due to inclusion in rebate schemes heat pump water heating systems are becoming increasingly popular, but do they result in lower greenhouse gas emissions? This study follows on from a previous life cycle assessment study of domestic hot water systems to include heat pump systems. The streamlined life cycle assessment approach used focused on the use phase of the life cycle, which was found in the previous study to be where the majority of global warming potential (GWP impacts occurred. Data was collected from an Australian heat pump manufacturer and was modelled assuming installation within Australian climate zone 3 (AS/NZS 4234:2011. Several scenarios were investigated for the heat pumps including different sources of electricity (grid, photovoltaic solar modules, and batteries and the use of solar thermal panels. It was found that due to their higher efficiency heat pump hot water systems can result in significantly lower GWP than electric storage hot water systems. Further, solar thermal heat pump systems can have lower GWP than solar electric hot water systems that use conventional electric boosting. Additionally, the contributions of HFC refrigerants to GWP can be significant so the use of alternative refrigerants is recommended. Heat pumps combined with PV and battery technology can achieve the lowest GWP of all domestic hot water systems.

In vivo evaluation of centrifugal blood pump for cardiopulmonary bypass-Spiral Pump.

Science.gov (United States)

da Silva, Cibele; da Silva, Bruno Utiyama; Leme, Juliana; Uebelhart, Beatriz; Dinkhuysen, Jarbas; Biscegli, José F; Andrade, Aron; Zavaglia, Cecília

2013-11-01

The Spiral Pump (SP), a centrifugal blood pump for cardiopulmonary bypass (CPB), has been developed at the Dante Pazzanese Institute of Cardiology/Adib Jatene Foundation laboratories, with support from Sintegra Company (Pompeia, Brazil). The SP is a disposable pump with an internal rotor-a conically shaped fuse with double entrance threads. This rotor is supported by two ball bearings, attached to a stainless steel shaft fixed to the housing base. Worm gears provide axial motion to the blood column, and the rotational motion of the conically shaped impeller generates a centrifugal pumping effect, improving pump efficiency without increasing hemolysis. In vitro tests were performed to evaluate the SP's hydrodynamic performance, and in vivo experiments were performed to evaluate hemodynamic impact during usual CPB. A commercially available centrifugal blood pump was used as reference. In vivo experiments were conducted in six male pigs weighing between 60 and 90 kg, placed on CPB for 6 h each. Blood samples were collected just before CPB (T0) and after every hour of CPB (T1-T6) for hemolysis determination and laboratory tests (hematological and biochemical). Values of blood pressure, mean flow, pump rotational speed, and corporeal temperature were recorded. Also, ergonomic conditions were recorded: presence of noise, difficulty in removing air bubbles, trouble in installing the pump in the drive module (console), and difficulties in mounting the CPB circuit. Comparing the laboratory and hemolysis results for the SP with those of the reference pump, we can conclude that there is no significant difference between the two devices. In addition, reports made by medical staff and perfusionists described a close similarity between the two devices. During in vivo experiments, the SP maintained blood flow and pressure at physiological levels, consistent with those applied in cardiac surgery with CPB, without presenting any malfunction. Also, the SP needed lower rotational

Darrieus wind-turbine and pump performance for low-lift irrigation pumping

Science.gov (United States)

Hagen, L. J.; Sharif, M.

1981-10-01

In the Great Plains about 15 percent of the irrigation water pumped on farms comes from surface water sources; for the United States as a whole, the figure is about 22 percent. Because of forecast fuel shortages, there is a need to develop alternative energy sources such as wind power for surface water pumping. Specific objectives of this investigation were to: design and assemble a prototype wind powered pumping system for low lift irrigation pumping; determine performance of the prototype system; design and test an irrigation system using the wind powered prototype in a design and test an farm application; and determine the size combinations of wind turbines, tailwater pits, and temporary storage reservoirs needed for successful farm application of wind powered tailwater pumping systems in western Kansas. The power source selected was a two bladed, 6 m diameter, 9 m tall Darrieus vertical axis wind turbine with 0.10 solidity and 36.1 M(2) swept area.

Pumped Storage Hydro Power Plant Cierny Vah

International Nuclear Information System (INIS)

Regula, E.

1998-01-01

diameter of a runner 2 600 mm. The pumps are single-inlet, two-stage. In 1985 the originally installed capacity 6 x 111.6 MW was increased in absorption capacity of the turbine to 6 x 122.4 MW after verification and tests by a supplier of technology. A Kaplan turbine TG7 set with installed capacity 0.768 MW and absorption capacity from 4.5 to 8 m 3 s 1 is installed for performing the natural flows of Cierny Vah in a building of the hydro power plant. Available power of the PSP is the most important contribution because if in thermal power stations a turbo-set must be kept in emergency, about 1000 tonnes of power engineering coal is annually burnt in it for each 1 megawatt installed. Thus, the Cierny Vah PSP saves 735 engineering coal annually

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

Evaluation of Ti-Zr-V (NEG) Thin Films for their pumping speed and pumping Capacity

International Nuclear Information System (INIS)

Bansod, Tripti; Sindal, B K; Kumar, K V A N P S; Shukla, S K

2012-01-01

Deposition of NEG thin films onto the interior walls of the vacuum chambers is an advanced technique to convert a vacuum chamber from a gas source to an effective pump. These films offer considerably large pumping speed for reactive gases like CO, H 2 etc. A UHV compatible pumping speed measurement system was developed in-house to measure the pumping speed of NEG coated chambers. To inject the fixed quantity of CO and H 2 gas in pumping speed measurement set-up a calibrated leak was also developed. Stainless steel chambers were sputter coated with thin film of Ti-Zr-V getter material using varied parameters for different compositions and thickness. Pumping capacity which is a function of sorbed gas quantities was also studied at various activation temperatures. In order to optimize the activation temperature for maximum pumping speed for CO and H 2 , pumping speeds were measured at room temperature after activation at different temperatures. The experimental system detail, pumping performance of the NEG film at various activation temperatures and RGA analysis are presented.

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

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.

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

Renewable energy technologies for irrigation water pumping in India: projected levels of dissemination, energy delivery and investment requirements using available diffusion models

Energy Technology Data Exchange (ETDEWEB)

Pallav Purohit; Kandpal, T.C. [Indian Institute of Technology, New Delhi (India). Centre for Energy Studies

2005-12-01

Using the past diffusion trends of four renewable energy technologies for irrigation water pumping in India (SPV pumps, windmill pumps and biogas/producer gas driven dual fuel engine pumps), results of an attempt to project their future dissemination levels, have been presented in this study. The likely contribution of the renewable energy options considered in the study to the projected energy demand for irrigation water pumping in India has been estimated. Estimates of the associated investment requirements taking into account the learning effect have also been presented. (author)

21 CFR 880.5725 - Infusion pump.

Science.gov (United States)

2010-04-01

... Infusion pump. (a) Identification. An infusion pump is a device used in a health care facility to pump fluids into a patient in a controlled manner. The device may use a piston pump, a roller pump, or a... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Infusion pump. 880.5725 Section 880.5725 Food and...

14 CFR 23.991 - Fuel pumps.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 23.991 Section 23.991... § 23.991 Fuel pumps. (a) Main pumps. For main pumps, the following apply: (1) For reciprocating engine installations having fuel pumps to supply fuel to the engine, at least one pump for each engine must be directly...

An economic evaluation comparison of solar water pumping system with engine pumping system for rice cultivation

Science.gov (United States)

Treephak, Kasem; Thongpron, Jutturit; Somsak, Dhirasak; Saelao, Jeerawan; Patcharaprakiti, Nopporn

2015-08-01

In this paper we propose the design and economic evaluation of the water pumping systems for rice cultivation using solar energy, gasoline fuel and compare both systems. The design of the water and gasoline engine pumping system were evaluated. The gasoline fuel cost used in rice cultivation in an area of 1.6 acres. Under same conditions of water pumping system is replaced by the photovoltaic system which is composed of a solar panel, a converter and an electric motor pump which is compose of a direct current (DC) motor or an alternating current (AC) motor with an inverter. In addition, the battery is installed to increase the efficiency and productivity of rice cultivation. In order to verify, the simulation and economic evaluation of the storage energy battery system with batteries and without batteries are carried out. Finally the cost of four solar pumping systems was evaluated and compared with that of the gasoline pump. The results showed that the solar pumping system can be used to replace the gasoline water pumping system and DC solar pump has a payback less than 10 years. The systems that can payback the fastest is the DC solar pumping system without batteries storage system. The system the can payback the slowest is AC solar pumping system with batteries storage system. However, VAC motor pump of 220 V can be more easily maintained than the motor pump of 24 VDC and batteries back up system can supply a more stable power to the pump system.

The evolving policy regime for pumped storage hydroelectricity in China: A key support for low-carbon energy

International Nuclear Information System (INIS)

Zhang, Sufang; Andrews-Speed, Philip; Perera, Pradeep

2015-01-01

Highlights: • Highlights the role of pumped storage hydroelectricity in renewable energy integration. • Examines the development of pumped storage hydroelectricity in China. • Reviews the regulatory policies on pumped storage hydroelectricity in China. • Analyzes the operation and pricing regime for pumped storage hydroelectricity in China. • Makes policy recommendations for promoting pumped storage hydroelectricity in China. - Abstract: As part of its energy transition strategy, China has set ambitious targets for increasing the contribution of renewable energy and, in particular, of wind power. However, the Chinese power sector has not undergone the necessary reforms to facilitate the integration and absorption of a larger share of variable renewable energy. This is evident from the difficulties in absorbing wind power from already commissioned wind farms and the resultant curtailment of wind power. Pumped storage hydroelectricity (PSH) is a flexible power source that can facilitate higher penetration levels of wind power as well as complement China’s growing nuclear power capacity. However, regulatory policy constraints have restricted the effective utilization of existing PSH capacity and discouraged investment in new PSH capacity. This paper examines these constraints and assesses the likely impact of new policies designed to address them. Finally, policy recommendations and concluding remarks are provided. This paper contributes to the literature on renewable energy integration from a new perspective. The lessons from China are relevant to other countries going through the energy transition

Design of dry scroll vacuum pumping system for efficient pumping of corrosive gas at medium vacuum range

International Nuclear Information System (INIS)

Banerjee, I.; Chandresh, B.G.; Guha, K.C.; Sarkar, S.

2015-01-01

Dry vacuum pumping systems attracts many applications because of its inherent capability of corrosion free pumping. It becomes a common trait of application in Thermo Nuclear Fusion, Semi conductor, Isotope separation industries etc. Thermo nuclear fusion requires a train of specially sealed roots pump backed by suitable capacity dry screw or reciprocating pump. Similarly corrosive fluoride gas pumping requires hermetically sealed specially designed dry scroll vacuum pump. Plant emergency operation however involves train of specially sealed roots pump backed with scroll pump for faster evacuation. In our attempt an indigenously designed scroll pump and associated system are designed to pump corrosive gases in a way to confine the corrosion product within the system. In order to execute the design, a numerical code for low pressure application is developed

Vacuum pumping concepts for ETF

International Nuclear Information System (INIS)

Homeyer, W.G.

1980-09-01

The Engineering Test Facility (ETF) poses unique vacuum pumping requirements due to its large size and long burn characteristics. These requirements include torus vacuum pumping initially and between burns and pumping of neutralized gas from divertor collector chambers. It was found that the requirements could be met by compound cryopumps in which molecular sieve 5A is used as the cryosorbent. The pumps, ducts, and vacuum valves required are large but fit with other ETF components and do not require major advances in vacuum pumping technology. Several additional design, analytical, and experimental studies were identified as needed to optimize designs and provide better design definition for the ETF vacuum pumping systems

Trial design and manufacture of double spiral grooved vacuum pump; Double neji mizoshiki shinku pump no shisaku

Energy Technology Data Exchange (ETDEWEB)

Iguchi, M.; Sawada, T.; Sugiyama, W. [Akita University, Akita (Japan). Faculty of Mining; Watanabe, M.

1997-04-25

A spiral grooved vacuum pump and a compound molecular pump (the combination of a spiral grooved pump and a turbomolecular pump) are widely used in the thin-film industry for processes such as semiconductor production. Pumping performance is high at pressures below 1 000 Pa and low at pressures above 1000 Pa when the clearance between rotor and stator is on the order of 0.1 mm, which is the practical value for industrial use. The double spiral grooved vacuum pump is thought to have better pumping performance at such high pressures than the conventional spiral grooved vacuum pump. The aim of this study is to investigate the feasibility of use of the double spiral grooved vacuum pump at pressures above 1000 Pa. A double spiral grooved vacuum pump with a rotor of 150 mm diameter and 190 mm length has been designed and manufactured. Its pumping performance has been tested by experiments. The test results show the improvement in the performance at pressures above 1000 Pa compared to the conventional spiral grooved vacuum pump. 2 refs., 12 figs., 2 tabs.

Absorption heat pumps

International Nuclear Information System (INIS)

Formigoni, C.

1998-01-01

A brief description of the difference between a compression and an absorption heat pump is made, and the reasons why absorption systems have spread lately are given. Studies and projects recently started in the field of absorption heat pumps, as well as criteria usually followed in project development are described. An outline (performance targets, basic components) of a project on a water/air absorption heat pump, running on natural gas or LPG, is given. The project was developed by the Robur Group as an evolution of a water absorption refrigerator operating with a water/ammonia solution, which has been on the market for a long time and recently innovated. Finally, a list of the main energy and cost advantages deriving from the use of absorption heat pumps is made [it

A simplified heat pump model for use in solar plus heat pump system simulation studies

DEFF Research Database (Denmark)

Perers, Bengt; Andersen, Elsa; Nordman, Roger

2012-01-01

Solar plus heat pump systems are often very complex in design, with sometimes special heat pump arrangements and control. Therefore detailed heat pump models can give very slow system simulations and still not so accurate results compared to real heat pump performance in a system. The idea here...

Careful system design. Current interim results of the heat pump field test; Das Gesamtsystem sorgfaeltig auslegen. Aktuelle Zwischenergebnisse im Waermepumpen-Feldtest

Energy Technology Data Exchange (ETDEWEB)

Miara, Marek [Fraunhofer-Institut fuer Solare Energiesysteme ISE, Freiburg (Germany)

2008-09-15

How efficient are modern electric heat pumps for newly constructed single-family dwellings? This question is to be answered by the project ''Waermepumpen-Effizienz'' (heat pump efficiency), a scientific field test that started in the summer of 2006. The contribution presents first results, including the measured performance data. Further, factors were identified that interfere with the optimum operation of heat pumps. (orig.)

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

Pump trials for charged liquids

International Nuclear Information System (INIS)

Moroni, J.C.; Niver, A.

1964-01-01

The pumps intended for the circulation of charged and radioactive liquids have particular qualities. The choice of such a pump has called for endurance tests with various types of equipment: a Goodyear volumetric screw pumps, and RICHIER, Klein and SCHABAVER centrifugal pumps. The latter, fitted with a special oakum, gave the best results. (authors) [fr

Thermally induced diffraction losses for a Gaussian pump beam and optimization of the mode-to-pump ratio in an end-pumped Nd:GdVO4 laser

International Nuclear Information System (INIS)

Wang, Y T; Li, W J; Pan, L L; Yu, J T; Zhang, R H

2013-01-01

The analytical model of thermally induced diffraction losses for a Gaussian pump beam are derived as functions of the mode-to-pump ratio and pump power in end-pumped Nd-doped lasers considering the energy transfer upconversion effects. The mode-to-pump ratio is optimized based on it. The results show that the optimum mode-to-pump ratio with the thermally induced diffraction losses is less than 0.65, and it is less than the results in which the thermally induced diffraction losses are neglected. The theoretical model is applied to a diode-end-pumped Nd:GdVO 4 laser operating at 1342 nm, and the theoretical calculations are in good agreement with the experimental results. (paper)

Pumps in mining

Energy Technology Data Exchange (ETDEWEB)

1979-01-01

This article looks at the pump industry as a whole, its historical links with the mining industry, their parallel develop ment, and at the individual manufacturers and pumps, services and auxillary products they have to offer.

Fast breeder reactor electromagnetic pump

International Nuclear Information System (INIS)

Araseki, Hideo; Murakami, Takahiro

2008-01-01

Main pumps circulating sodium in the FBR type reactor have been mechanical types, not electromagnetic pumps. Electromagnetic pump of 1-2 m 3 /min has been used as an auxiliary pump. Large sized electromagnetic pumps such as several hundred m 3 /min have not been commercialized due to technical difficulties with electromagnetic instability and pressure pulsations. This article explained electromagnetic and fluid equations and magnetic Reynolds number related with electromagnetic pumps and numerical analysis of instability characteristics and pressure pulsations and then described applications of the results to FBR system. Magnetic Reynolds number must be chosen less than one with appropriate operating frequency and optimum slip of 0.2-0.4. (T. Tanaka)

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)

Bearing for liquid metal pump

International Nuclear Information System (INIS)

Dickinson, R.J.; Pennell, W.E.; Wasko, J.

1984-01-01

A liquid metal pump bearing support comprises a series of tangentially oriented spokes that connect the bearing cylinder to the pump internals structure. The spokes may be arranged in a plurality of planes extending from the bearing cylinder to the pump internals with the spokes in one plane being arranged alternately with those in the next plane. The bearing support structure provides the pump with sufficient lateral support for the bearing structure together with the capability of accommodating differential thermal expansion without adversely affecting pump performance

High-inertia hermetically sealed main coolant pump for next generation passive nuclear power plants

International Nuclear Information System (INIS)

Kujawski, Joseph M.; Nair, Bala R.; Vijuk, Ronald P.

2003-01-01

The main coolant pump for the Westinghouse AP1000 advanced passive nuclear power plant represents a significant scale-up in power, flow capacity, and physical size from its predecessor designed for the smaller AP600 power plant. More importantly, the AP1000 pump incorporates several innovative features that contribute to improved efficiency, operational reliability, and plant safety. The features include an internals design which provides the highest hydraulic efficiency achieved in commercial nuclear power plant applications. Another feature is the use of a distributed inertial mass system in the rotating assembly to develop the high rotational inertia to meet the extended system flow coastdown requirement for core heat removal in the event of loss of power to the pumps. This advanced canned motor pump also incorporates the latest development in higher operating voltage, providing plant designers with the ability to eliminate plant transformers and operate directly on the site electrical bus in many cases. The salient features of the pump design and performance data are presented in this paper. (author)

Rotary magnetic heat pump

Science.gov (United States)

Kirol, L.D.

1987-02-11

A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

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)

A contribution to water hammer analysis in pumped-storage power plants; Ein Beitrag zur Druckstossberechnung von Pumpspeicheranlagen

Energy Technology Data Exchange (ETDEWEB)

Hoeller, Stefan; Jaberg, Helmut [TU Graz (Austria). Inst. fuer Hydraulische Stroemungsmaschinen

2013-03-01

The operation of pumped-storage power plants induces a highly transient fluid flow in the penstock of high head water power plants. In the planning phase a reliable prediction of the transient plant behaviour in unsteady load cases such as e.g. machine start or switching load cases is necessary. Numerical simulation methods provide a tool to calculate the occurring pressure pulsations or mass oscillations as well as for the optimization of the transient behaviour. Commercial software-packages for water hammer simulations usually do not provide numerical models for a realistic calculation of complex components like surge tanks, turbines or emergency closing valves in a high head water power plant. But especially these components need to be modelled correctly in order to get a significant and reliable solution. This article shows the practice ofthe development of a custom-designed numerical model on the example of a pump turbine. (orig.)

Development and Optimized Design of Propeller Pump System & Structure with VFD in Low-head Pumping Station

Science.gov (United States)

Rentian, Zhang; Honggeng, Zhu; Arnold, Jaap; Linbi, Yao

2010-06-01

Compared with vertical-installed pumps, the propeller (bulb tubular) pump systems can achieve higher hydraulic efficiencies, which are particularly suitable for low-head pumping stations. More than four propeller pumping stations are being, or will be built in the first stage of the S-to-N Water Diversion Project in China, diverting water from Yangtze River to the northern part of China to alleviate water-shortage problems and develop the economy. New structures of propeller pump have been developed for specified pumping stations in Jiangsu and Shandong Provinces respectively and Variable Frequency Drives (VFDs) are used in those pumping stations to regulate operating conditions. Based on the Navier-Stokes equations and the standard k-e turbulent model, numerical simulations of the flow field and performance prediction in the propeller pump system were conducted on the platform of commercial software CFX by using the SIMPLEC algorithm. Through optimal design of bulb dimensions and diffuser channel shape, the hydraulic system efficiency has improved evidently. Furthermore, the structures of propeller pumps have been optimized to for the introduction of conventional as well as permanent magnet motors. In order to improve the hydraulic efficiency of pumping systems, both the pump discharge and the motor diameter were optimized respectively. If a conventional motor is used, the diameter of the pump casing has to be increased to accommodate the motor installed inside. If using a permanent magnet motor, the diameter of motor casing can be decreased effectively without decreasing its output power, thus the cross-sectional area is enlarged and the velocity of flowing water decreased favorably to reduce hydraulic loss of discharge channel and thereby raising the pumping system efficiency. Witness model tests were conducted after numerical optimization on specific propeller pump systems, indicating that the model system hydraulic efficiencies can be improved by 0.5%˜3.7% in

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

Variations in battery life of a heart-lung machine using different pump speeds, pressure loads, boot material, centrifugal pump head, multiple pump usage, and battery age.

LENUS (Irish Health Repository)

Marshall, Cornelius

2012-02-03

Electrical failure during cardiopulmonary bypass (CPB) has previously been reported to occur in 1 of every 1500 cases. Most heart-lung machine pump consoles are equipped with built-in battery back-up units. Battery run times of these devices are variable and have not been reported. Different conditions of use can extend battery life in the event of electrical failure. This study was designed to examine the run time of a fully charged battery under various conditions of pump speed, pressure loads, pump boot material, multiple pump usage, and battery life. Battery life using a centrifugal pump also was examined. The results of this study show that battery life is affected by pump speed, circuit pressure, boot stiffness, and the number of pumps in service. Centrifugal pumps also show a reduced drain on battery when compared with roller pumps. These elements affect the longevity and performance of the battery. This information could be of value to the individual during power failure as these are variables that can affect the battery life during such a challenging scenario.

LMR [liquid metal reactor] centrifugal pump coastdowns

International Nuclear Information System (INIS)

Dunn, F.E.; Malloy, D.J.

1987-01-01

A centrifugal pump model which describes the interrelationships of the pump discharge flowrate, pump speed, shaft torque and dynamic head has been implemented based upon existing models. Specifically, the pump model is based upon the dimensionless-homologous pump theory of Wylie and Streeter. Given data from a representative pump, homologous theory allows one to predict the transient characteristics of similarly sized pumps. This homologous pump model has been implemented into both the one-dimensional SASSYS-1 systems analysis code and the three-dimensional COMMIX-1A code. Comparisons have been made both against other pump models (CRBR) and actual pump coastdown data (EBR-II and FFTF). Agreement with this homologous pump model has been excellent. Additionally, these comparisons indicate the validity of applying the medium size pump data of Wylie and Streeter to a range of typical LMR centrifugal pumps

Model and simulation of Na+/K+ pump phosphorylation in the presence of palytoxin.

Science.gov (United States)

Rodrigues, Antônio M; Almeida, Antônio-Carlos G; Infantosi, Antonio F C; Teixeira, Hewerson Z; Duarte, Mario A

2008-02-01

The ATP hydrolysis reactions responsible for the Na(+)/K(+)-ATPase phosphorylation, according to recent experimental evidences, also occur for the PTX-Na(+)/K(+) pump complex. Moreover, it has been demonstrated that PTX interferes with the enzymes phosphorylation status. However, the reactions involved in the PTX-Na(+)/K(+) pump complex phosphorylation are not very well established yet. This work aims at proposing a reaction model for PTX-Na(+)/K(+) pump complex, with similar structure to the Albers-Post model, to contribute to elucidate the PTX effect over Na(+)/K(+)-ATPase phosphorylation and dephosphorylation. Computational simulations with the proposed model support several hypotheses and also suggest: (i) phosphorylation promotes an increase of the open probability of induced channels; (ii) PTX reduces the Na(+)/K(+) pump phosphorylation rate; (iii) PTX may cause conformational changes to substates where the Na(+)/K(+)-ATPase may not be phosphorylated; (iv) PTX can bind to substates of the two principal states E1 and E2, with highest affinity to phosphorylated enzymes and with ATP bound to its low-affinity sites. The proposed model also allows previewing the behavior of the PTX-pump complex substates for different levels of intracellular ATP concentrations.

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

Pump Early, Pump Often: A Continuous Quality Improvement Project.

Science.gov (United States)

Spatz, Diane L; Froh, Elizabeth B; Schwarz, Jessica; Houng, Kathy; Brewster, Isabel; Myers, Carey; Prince, Judy; Olkkola, Michelle

2015-01-01

Research demonstrates that although many mothers initiate pumping for their critically ill children, few women are successful at maintaining milk supply throughout their infants' entire hospital stay. At the Garbose Family Special Delivery Unit (SDU) at the Children's Hospital of Philadelphia, we care for mothers who have critically ill infants born with complex cardiac and congenital anomalies. Human milk is viewed as a medical intervention at our institution. Therefore, nurses on the SDU wanted to ensure best practice in terms of pumping initiation. This article describes a continuous quality improvement project that ensured mothers pumped early and often. Childbirth educators can play a key role in preparing mothers who are anticipating an infant who will require hospitalization immediately post-birth.

RND-type Drug Efflux Pumps from Gram-negative bacteria: Molecular Mechanism and Inhibition

Directory of Open Access Journals (Sweden)

Henrietta eVenter

2015-04-01

Full Text Available Drug efflux protein complexes confer multidrug resistance on bacteria by transporting a wide spectrum of structurally diverse antibiotics. Moreover, organisms can only acquire resistance in the presence of an active efflux pump. The substrate range of drug efflux pumps is not limited to antibiotics, but it also includes toxins, dyes, detergents, lipids and molecules involved in quorum sensing; hence efflux pumps are also associated with virulence and biofilm formation. Inhibitors of efflux pumps are therefore attractive compounds to reverse multidrug resistance and to prevent the development of resistance in clinically relevant bacterial pathogens. Recent successes on the structure determination and functional analysis of the AcrB and MexB components of the AcrAB-TolC and MexAB-OprM drug efflux systems as well as the structure of the fully assembled, functional triparted AcrAB-TolC complex significantly contributed to our understanding of the mechanism of substrate transport and the options for inhibition of efflux. These data, combined with the well-developed methodologies for measuring efflux pump inhibition, could allow the rational design and subsequent experimental verification of potential efflux pump inhibitors. In this review we will explore how the available biochemical and structural information can be translated into the discovery and development of new compounds that could reverse drug resistance in Gram-negative pathogens. The current literature on efflux pump inhibitors will also be analysed and the reasons why no compounds have yet progressed into clinical use will be explored.

Improvements relating to electromagnetic pumps

International Nuclear Information System (INIS)

Davidson, D.F.

1975-01-01

Reference is made to electromagnetic pumps suitable for use in pumping molten Na, and particularly to annular linear induction pumps that may for example be used to pump molten Na at temperatures up to 650 0 in situations where it is not possible to provide cooling. Previous designs of such pumps have employed disk-shaped coils around the outside of the annulus, the coils being energised from a three-phase power supply to produce a travelling radial field. The pump system described obviates the necessity for joints between the coils. It also allows the use of all types of high temperature insultation, simplified manufacture, and enables the windings to be located on the inside of the annulus. Full constructional details are given. (U.K.)

Value of pumped hydro storage in a hybrid energy generation and allocation system

International Nuclear Information System (INIS)

Kocaman, Ayse Selin; Modi, Vijay

2017-01-01

Highlights: •We propose a two-stage stochastic mixed-integer programming model for a hybrid energy system. •We investigate the solar and PHES integration considering the streamflow uncertainty. •We study the benefit of PHES system over conventional hydropower systems to support solar. •We examine the role of PHES systems in both isolated and connected systems. -- Abstract: Transition from fossil fuels to renewable sources is inevitable. In this direction, variation and intermittency of renewables can be integrated into the grid by means of hybrid systems that operate as a combination of alternative resources, energy storage and long distance transmission lines. In this study, we propose a two-stage stochastic mixed-integer programming model for sizing an integrated hybrid energy system, in which intermittent solar generation in demand points is supported by pumped hydro storage (PHES) systems and diesel is used as an expensive back-up source. PHES systems work as a combination of pumped storage and conventional hydropower stations since there is also natural streamflow coming to the upper reservoirs that shows significant seasonal and inter-annual variability and uncertainty. With several case studies from India, we examine the role of high hydropower potential in the Himalaya Mountains to support solar energy generation in the form of pumped hydro or conventional hydro system while meeting the demand at various scales. We show that pumped hydro storage can keep the diesel contribution to meet the demand less than 10%, whereas this number can go up to more than 50% for conventional systems where the streamflow potential is limited compared to the demand. We also examine the role of pumped hydro systems in both isolated and connected systems (through inter-regional transmission lines) and show that the benefit of pumped hydro is more significant in isolated systems and resource-sharing in connected systems can substitute for energy storage. In addition, with

Influence of diatom diversity on the ocean biological carbon pump

Science.gov (United States)

Tréguer, Paul; Bowler, Chris; Moriceau, Brivaela; Dutkiewicz, Stephanie; Gehlen, Marion; Aumont, Olivier; Bittner, Lucie; Dugdale, Richard; Finkel, Zoe; Iudicone, Daniele; Jahn, Oliver; Guidi, Lionel; Lasbleiz, Marine; Leblanc, Karine; Levy, Marina; Pondaven, Philippe

2018-01-01

Diatoms sustain the marine food web and contribute to the export of carbon from the surface ocean to depth. They account for about 40% of marine primary productivity and particulate carbon exported to depth as part of the biological pump. Diatoms have long been known to be abundant in turbulent, nutrient-rich waters, but observations and simulations indicate that they are dominant also in meso- and submesoscale structures such as fronts and filaments, and in the deep chlorophyll maximum. Diatoms vary widely in size, morphology and elemental composition, all of which control the quality, quantity and sinking speed of biogenic matter to depth. In particular, their silica shells provide ballast to marine snow and faecal pellets, and can help transport carbon to both the mesopelagic layer and deep ocean. Herein we show that the extent to which diatoms contribute to the export of carbon varies by diatom type, with carbon transfer modulated by the Si/C ratio of diatom cells, the thickness of the shells and their life strategies; for instance, the tendency to form aggregates or resting spores. Model simulations project a decline in the contribution of diatoms to primary production everywhere outside of the Southern Ocean. We argue that we need to understand changes in diatom diversity, life cycle and plankton interactions in a warmer and more acidic ocean in much more detail to fully assess any changes in their contribution to the biological pump.

Influence of individual heat pumps on wind power integration – Energy system investments and operation

DEFF Research Database (Denmark)

Hedegaard, Karsten; Münster, Marie

2013-01-01

Individual heat pumps are expected to constitute a significant electricity demand in future energy systems. This demand becomes flexible if investing in complementing heat storage capabilities. In this study, we analyse how the heat pumps can influence the integration of wind power by applying...... an energy system model that optimises both investments and operation, and covers various heat storage options. The Danish energy system by 2030 with around 50–60% wind power is used as a case study. Results show that the heat pumps, even without flexible operation, can contribute significantly...... to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO2 emissions. Investments in heat storages can provide only moderate system benefits in these respects. The main benefit of the flexible heat pump operation is a reduced need for peak/reserve capacity, which is also...

46 CFR 119.520 - Bilge pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Bilge pumps. 119.520 Section 119.520 Shipping COAST... Ballast Systems § 119.520 Bilge pumps. (a) Each vessel must be provided with bilge pumps in accordance... have a portable hand bilge pump that must be: (1) Capable of pumping water, but not necessarily...

Reactor coolant pumps for nuclear reactors

International Nuclear Information System (INIS)

Harand, E.; Richter, G.; Tschoepel, G.

1975-01-01

A brake for the pump rotor of a main coolant pump or a shutoff member on the pump are provided in order to prevent excess speeds of the pump rotor. Such excess speeds may occur in PWR type reactors with water at a pressure below, e.g., 150 bars if there is leakage from a coolant line associated with the main coolant pump. As a brake, a centrifugal brake depending upon the pump speed or a brake ring arranged on the pump housing and acting on the pump rotor, which ring would be activated by pressure differentials in the pump, may be used. If the pressure differences between suction and pressure sockets are very small, a controlled hydraulic increase of the pressure force on the brake may also be provided. Furthermore, a turbine brake may be provided. A slide which is automatically movable in closing position along the pump rotor axis is used as a shutoff element. It is of cylindrical configuration and is arranged concentrically with the rotor axis. (DG) [de

Development of new design mechanical seal tester for Primary Loop Recirculation Pump (PLR Pump)

International Nuclear Information System (INIS)

Fukushima, Naoki; Koshiba, Koremutsu

1995-01-01

The mechanical seal for a Primary Loop Recirculation Pump (PLR Pump) is an important part of a BWR plant. This study describes a new mechanical seal tester developed to certify mechanical seal performance before installation in a PLR Pump on site. (author)

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

Diode-laser-pump module with integrated signal ports for pumping amplifying fibers and method

Science.gov (United States)

Savage-Leuchs,; Matthias, P [Woodinville, WA

2009-05-26

Apparatus and method for collimating pump light of a first wavelength from laser diode(s) into a collimated beam within an enclosure having first and second optical ports, directing pump light from the collimated beam to the first port; and directing signal light inside the enclosure between the first and second port. The signal and pump wavelengths are different. The enclosure provides a pump block having a first port that emits pump light to a gain fiber outside the enclosure and that also passes signal light either into or out of the enclosure, and another port that passes signal light either out of or into the enclosure. Some embodiments use a dichroic mirror to direct pump light to the first port and direct signal light between the first and second ports. Some embodiments include a wavelength-conversion device to change the wavelength of at least some of the signal light.

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.

Study of particle pumping characteristics for different pumping geometries in JT-60U and DIII-D divertors

International Nuclear Information System (INIS)

Takenaga, H.; Sakasai, A.; Kubo, H.

2001-01-01

Particle pumping characteristics were compared between pumping from the inner side private flux region (IPP) and pumping from both sides of the private flux region (BPP) in the JT-60U W shaped divertor, and between JT-60U IPP and pumping in the DIII-D lower baffled divertor. The pumping flux for BPP is smaller than that for IPP by about a factor of 2 with weak in-out asymmetry of recycling neutral flux and by a factor of 3.5-6.5 with strong in-out asymmetry. The reduction of the pumping flux for BPP is consistent with Monte Carlo simulations, where backflow at the outer pumping slot is observed due to in-out recycling asymmetry. The pumping flux in DIII-D at I p =0.8 MA and B T =1.6 T is comparable to or smaller than that for JT-60U IPP at I p =1.0 MA, B T =3.8 T and I p =1.5 MA, B T =3.5 T in the same density regime. In the DIII-D divertor with pumping from the private flux region, the pumping flux decreases with increasing in-out asymmetry. The pumping flux normalized by the integrated D α emission over the whole plasma exhibits a similar dependence on the distance between the pumping slot and the strike point in JT-60U IPP and the DIII-D lower divertor with pumping through the outer divertor plasma region. (author)

JET pump limiter

International Nuclear Information System (INIS)

Sonnenberg, K.; Deksnis, E.; Shaw, R.; Reiter, D.

1988-01-01

JET plans to install two pump limiter modules which can be used for belt-limiter, inner-wall and X-point discharges and, also, for 1-2s as the main limiter. A design is presented which is compatible with two diagnostic systems, and which allows partial removal of the pump limiter to provide access for remote-handling operations. The high heat-flux components are initially cooled during a pulse. Heat is removed between discharges by radiation and pressure contacts to a water-cooled support structure. The pumping edge will be made of annealed pyrolytic graphite. Exhaust efficiency has been estimated, for a 1-d edge model, using a Monte-Carlo calculation of neutral gas transport. When the pump limiter is operated together with other wall components we expect an efficiency of ≅ 5% (2.5 x 10 21 part/s). As a main limiter the efficiency increases to about 10%. (author)

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.

Thermally Actuated Hydraulic Pumps

Science.gov (United States)

Jones, Jack; Ross, Ronald; Chao, Yi

2008-01-01

Thermally actuated hydraulic pumps have been proposed for diverse applications in which direct electrical or mechanical actuation is undesirable and the relative slowness of thermal actuation can be tolerated. The proposed pumps would not contain any sliding (wearing) parts in their compressors and, hence, could have long operational lifetimes. The basic principle of a pump according to the proposal is to utilize the thermal expansion and contraction of a wax or other phase-change material in contact with a hydraulic fluid in a rigid chamber. Heating the chamber and its contents from below to above the melting temperature of the phase-change material would cause the material to expand significantly, thus causing a substantial increase in hydraulic pressure and/or a substantial displacement of hydraulic fluid out of the chamber. Similarly, cooling the chamber and its contents from above to below the melting temperature of the phase-change material would cause the material to contract significantly, thus causing a substantial decrease in hydraulic pressure and/or a substantial displacement of hydraulic fluid into the chamber. The displacement of the hydraulic fluid could be used to drive a piston. The figure illustrates a simple example of a hydraulic jack driven by a thermally actuated hydraulic pump. The pump chamber would be a cylinder containing encapsulated wax pellets and containing radial fins to facilitate transfer of heat to and from the wax. The plastic encapsulation would serve as an oil/wax barrier and the remaining interior space could be filled with hydraulic oil. A filter would retain the encapsulated wax particles in the pump chamber while allowing the hydraulic oil to flow into and out of the chamber. In one important class of potential applications, thermally actuated hydraulic pumps, exploiting vertical ocean temperature gradients for heating and cooling as needed, would be used to vary hydraulic pressures to control buoyancy in undersea research

Lunar Base Heat Pump

Science.gov (United States)

Walker, D.; Fischbach, D.; Tetreault, R.

1996-01-01

The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

Thermomechanical piston pump development

Science.gov (United States)

Sabelman, E. E.

1971-01-01

A thermally powered reciprocating pump has been devised to replace or augment an electric pump for the transport of temperature-control fluid on the Thermoelectric Outer Planet Spacecraft (TOPS). The thermally powered pump operates cyclically by extracting heat energy from the fluid by means of a vapor-pressure expansion system and by using the heat to perform the mechanical work of pumping. A feasibility test unit has been constructed to provide an output of 7 cu in during a 10- to 100-second cycle. It operates with a fluid input temperature of 200 to 300 F and a heat sink temperature of 0 to 30 F.

Analysis of femtosecond pump-probe photoelectron-photoion coincidence measurements applying Bayesian probability theory

Science.gov (United States)

Rumetshofer, M.; Heim, P.; Thaler, B.; Ernst, W. E.; Koch, M.; von der Linden, W.

2018-06-01

Ultrafast dynamical processes in photoexcited molecules can be observed with pump-probe measurements, in which information about the dynamics is obtained from the transient signal associated with the excited state. Background signals provoked by pump and/or probe pulses alone often obscure these excited-state signals. Simple subtraction of pump-only and/or probe-only measurements from the pump-probe measurement, as commonly applied, results in a degradation of the signal-to-noise ratio and, in the case of coincidence detection, the danger of overrated background subtraction. Coincidence measurements additionally suffer from false coincidences, requiring long data-acquisition times to keep erroneous signals at an acceptable level. Here we present a probabilistic approach based on Bayesian probability theory that overcomes these problems. For a pump-probe experiment with photoelectron-photoion coincidence detection, we reconstruct the interesting excited-state spectrum from pump-probe and pump-only measurements. This approach allows us to treat background and false coincidences consistently and on the same footing. We demonstrate that the Bayesian formalism has the following advantages over simple signal subtraction: (i) the signal-to-noise ratio is significantly increased, (ii) the pump-only contribution is not overestimated, (iii) false coincidences are excluded, (iv) prior knowledge, such as positivity, is consistently incorporated, (v) confidence intervals are provided for the reconstructed spectrum, and (vi) it is applicable to any experimental situation and noise statistics. Most importantly, by accounting for false coincidences, the Bayesian approach allows us to run experiments at higher ionization rates, resulting in a significant reduction of data acquisition times. The probabilistic approach is thoroughly scrutinized by challenging mock data. The application to pump-probe coincidence measurements on acetone molecules enables quantitative interpretations

Multi-stage internal gear/turbine fuel pump

Energy Technology Data Exchange (ETDEWEB)

Maier, Eugen; Raney, Michael Raymond

2004-07-06

A multi-stage internal gear/turbine fuel pump for a vehicle includes a housing having an inlet and an outlet and a motor disposed in the housing. The multi-stage internal gear/turbine fuel pump also includes a shaft extending axially and disposed in the housing. The multi-stage internal gear/turbine fuel pump further includes a plurality of pumping modules disposed axially along the shaft. One of the pumping modules is a turbine pumping module and another of the pumping modules is a gerotor pumping module for rotation by the motor to pump fuel from the inlet to the outlet.

Pump pulse duration dependence of coherent phonon amplitudes in antimony

Energy Technology Data Exchange (ETDEWEB)

Misochko, O. V., E-mail: misochko@issp.ac.ru [Russian Academy of Sciences, Institute of Solid State Physics (Russian Federation)

2016-08-15

Coherent optical phonons of A{sub 1k} and E{sub k} symmetry in antimony have been studied using the femtosecond pump–probe technique. By varying the pump-pulse duration and keeping the probe duration constant, it was shown that the amplitude of coherent phonons of both symmetries exponentially decreases with increasing pulse width. It was found that the amplitude decay rate for the fully symmetric phonons with larger frequency is greater than that of the doubly degenerate phonons, whereas the frequency and lifetime for coherent phonons of both symmetries do not depend on the pump-pulse duration. Based on this data, the possibility of separation between dynamic and kinematic contributions to the generation mechanism of coherent phonons is discussed.

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.

Using NEG-pumping near a high density internal target

Energy Technology Data Exchange (ETDEWEB)

Gruber, Alexander; Marton, Johann; Widmann, Eberhard; Zmeskal, Johann [Stefan Meyer Institut fuer Subatomare Physik, OeAW (Germany); Orth, Herbert [GSI, Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany)

2009-07-01

The universal detector PANDA will be constructed at the future high-energy antiproton storage ring HESR at FAIR (Facility for Antiproton and Ion Research, GSI/Darmstadt). It will use antiproton beams (1.5 to 15 GeV/c) for hadron physics in the charmonium region. The Stefan Meyer Institut (SMI) contributes to major parts of the PANDA detector like the hydrogen cluster-jet target and the vacuum system of the antiproton - target interaction zone. To ensure low background, the residual gas load in the interaction zone and in the antiproton beam-pipe has to be minimised. Most of the gas load will come from the high density internal hydrogen target. As the detector will cover almost the full solid angle, the installation of pumps near the interaction zone is impossible. Therefore the use of NEG (non-evaporative-getter) coated beam pipes has been considered as an alternative. Two setups with NEG coated tubes have been installed at SMI as prototypes of the PANDA interaction zone. General parameters of the NEG-film, its outgassing behaviour, the pumping speed and the pumping capacity for hydrogen have been tested. The results of the studies on the PANDA-interaction region are presented.

Pumps for German pressurized water reactors

Energy Technology Data Exchange (ETDEWEB)

Dernedde, R.

1984-01-01

The article describes the development of a selection of pumps which are used in the primary coolant system and the high-pressure safety injection system and feed water system during the past 2 decades. The modifications were caused by the step-wise increasing power output of the plants from 300 MW up to 1300 MW. Additional important influences were given be the increased requirements for quality assurance and final-documentation. The good operating results of the delivered pumps proved that the reliability is independent of the volume of the software-package. The outlook expects that consolidation will be followed by additional steps for the order processing of components for the convoy pumps. KW: main coolant pump; primary system; boiler feed pump; reactor pump; secondary system; barrel insert pump; pressure water reactor; convoy pump; state of the art.

High pressure liquid gas pump

Science.gov (United States)

Acres, R. L.

1972-01-01

Design and development of two types of pumps for handling liquefied gases are discussed. One pump uses mechanical valve shift and other uses pneumatic valve shift. Illustrations of pumps are provided and detailed description of operation is included.

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

FAWA - Field-analysis of Heat-pump Installations - Proceedings; Tagungsband zur 11. Tagung des Forschungsprogramms Umgebungswaerme, Waerme-Kraft-Kopplung, Kaelte des Bundesamts fuer Energie (BFE)

Energy Technology Data Exchange (ETDEWEB)

Rognon, F.

2004-07-01

These proceedings of the 11th conference organised by the Swiss Federal Office of Energy's Research Programme on Ambient Heat, Combined Heat and Power and Refrigeration present 6 papers on heat-pump topics. These include two papers concerning the results obtained from the FAWA project - a unique study of over 230 heat pump installations in operation in the field that was started in 1996 to assess the success of Swiss heat-pump promotion activities. The activities of the Swiss Heat-pump Testing Centre are dealt with and the potential for cost reductions through the optimal choice of system - done according to the motto 'small and simple is beautiful' - is reviewed. A further contribution deals with the question of the heat-pump customer being the 'king'. The role of installers and fitters acting as the instances who choose which system is to be used is looked at in a further contribution. A list of useful addresses completes the proceedings.

Solar collectors and heat pump: Market review and preliminary simulation results

International Nuclear Information System (INIS)

Tepe, Rainer; Roennelid, Mats

2002-01-01

Heating systems that combine solar collectors and a heat pump available on the market in Sweden have been studied. A majority of the systems found combine the solar collectors with a ground source heat pump. The technology for combining the collectors and the heat pump does however vary considerably. In the most simple systems, the collectors heat the return water from the heat pump, i.e. the collectors are used for raising the temperature in the boreholes for the heat pump. In the advanced systems, the solar heat is used for tap water, space heating and for raising the temperature of the heat pump's evaporator. There exist only very few comparative evaluations of the contributions from solar collectors in heat pump systems, and there is a need for finding the potential for this technique. In the present study, results are reported from preliminary simulations of solar collectors and ground source heat pumps installed in one-family houses. Simulations are made for two heating loads: 8,650 and 16,500 kWh/year resp., and a hot water load of 3,000 kWh/year. The study shows that: the temperature of the borehole decreases when solar collectors are not used (about 1.2 deg C in three years): 8 m 2 glazed solar collectors used for hot water production can reduce the electricity consumption with up to 13%, with best results in the house with low heating load: 50 m 2 unglazed solar collectors coupled to the evaporator or the borehole can give reductions of up to 14%, largest reduction in the house with high heating load, where the heat extraction from the borehole is large: the unglazed collectors have the highest economic potential, and can be cost effective for houses with high heating load: the simulations do not include a thorough system optimization, better results can be expected from continued optimization work

Nuclear-pumped lasers

CERN Document Server

Prelas, Mark

2016-01-01

This book focuses on Nuclear-Pumped Laser (NPL) technology and provides the reader with a fundamental understanding of NPLs, a review of research in the field, and exploration of large scale NPL system design and applications. Early chapters look at the fundamental properties of lasers, nuclear-pumping and nuclear reactions that may be used as drivers for nuclear-pumped lasers. The book goes on to explore the efficient transport of energy from the ionizing radiation to the laser medium and then the operational characteristics of existing nuclear-pumped lasers. Models based on Mathematica, explanations and a tutorial all assist the reader’s understanding of this technology. Later chapters consider the integration of the various systems involved in NPLs and the ways in which they can be used, including beyond the military agenda. As readers will discover, there are significant humanitarian applications for high energy/power lasers, such as deflecting asteroids, space propulsion, power transmission and mining....

Pumping tests in nonuniform aquifers - The radially symmetric case

Science.gov (United States)

Butler, J.J.

1988-01-01

Traditionally, pumping-test-analysis methodology has been limited to applications involving aquifers whose properties are assumed uniform in space. This work attempts to assess the applicability of analytical methodology to a broader class of units with spatially varying properties. An examination of flow behavior in a simple configuration consisting of pumping from the center of a circular disk embedded in a matrix of differing properties is the basis for this investigation. A solution describing flow in this configuration is obtained through Laplace-transform techniques using analytical and numerical inversion schemes. Approaches for the calculation of flow properties in conditions that can be roughly represented by this simple configuration are proposed. Possible applications include a wide variety of geologic structures, as well as the case of a well skin resulting from drilling or development. Of more importance than the specifics of these techniques for analysis of water-level responses is the insight into flow behavior during a pumping test that is provided by the large-time form of the derived solution. The solution reveals that drawdown during a pumping test can be considered to consist of two components that are dependent and independent of near-well properties, respectively. Such an interpretation of pumping-test drawdown allows some general conclusions to be drawn concerning the relationship between parameters calculated using analytical approaches based on curve-matching and those calculated using approaches based on the slope of a semilog straight line plot. The infinite-series truncation that underlies the semilog analytical approaches is shown to remove further contributions of near-well material to total drawdown. In addition, the semilog distance-drawdown approach is shown to yield an expression that is equivalent to the Thiem equation. These results allow some general recommendations to be made concerning observation-well placement for pumping

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

The Effects of Altered Membrane Cholesterol Levels on Sodium Pump Activity in Subclinical Hypothyroidism

Directory of Open Access Journals (Sweden)

Suparna Roy

2017-02-01

Full Text Available BackgroundMetabolic dysfunctions characteristic of overt hypothyroidism (OH start at the early stage of subclinical hypothyroidism (SCH. Na+/K+-ATPase (the sodium pump is a transmembrane enzyme that plays a vital role in cellular activities in combination with membrane lipids. We evaluated the effects of early changes in thyroid hormone and membrane cholesterol on sodium pump activity in SCH and OH patients.MethodsIn 32 SCH patients, 35 OH patients, and 34 euthyroid patients, sodium pump activity and cholesterol levels in red blood cell membranes were measured. Serum thyroxine (T4 and thyroid stimulating hormone (TSH levels were measured using enzyme-linked immunosorbent assays. Differences in their mean values were analysed using post hoc analysis of variance. We assessed the dependence of the sodium pump on other metabolites by multiple regression analysis.ResultsSodium pump activity and membrane cholesterol were lower in both hypothyroid groups than in control group, OH group exhibiting lower values than SCH group. In SCH group, sodium pump activity showed a significant direct dependence on membrane cholesterol with an inverse relationship with serum TSH levels. In OH group, sodium pump activity depended directly on membrane cholesterol and serum T4 levels. No dependence on serum cholesterol was observed in either case.ConclusionDespite the presence of elevated serum cholesterol in hypothyroidism, membrane cholesterol contributed significantly to maintain sodium pump activity in the cells. A critical reduction in membrane cholesterol levels heralds compromised enzyme activity, even in the early stage of hypothyroidism, and this can be predicted by elevated TSH levels alone, without any evident clinical manifestations.

Pumps for nuclear industry

International Nuclear Information System (INIS)

Tanguy, L.

1978-01-01

In order to meet the requirements of nuclear industry for the transfer of corrosive, toxic, humidity sensitive or very pure gases, different types of pumps were developped and commercialized. Their main characteristics are to prevent pollution of the transfered fluid by avoiding any contact between this fluid and the lubricated parts of the machine, and to prevent a contamination of the atmosphere or of the fluid by a total tightness. Patellar pumps have been particularly developped because the metallic bellows are quite reliable and resistant in this configuration. Two types are described: patellar pumps without friction and barrel pumps whose pistons are provided with rings sliding in the cylinders without lubrication [fr

Baxter elastomeric pumps: Feasibility of weight estimates.

Science.gov (United States)

Chambers, Carole R; Pabia, Mica; Sawyer, Michael; Tang, Patricia A

2017-09-01

Purpose Elastomeric pumps are used to infuse a 46-h fluorouracil protocol and patients are asked to visually inspect the pump daily. The pump has a variability of ±10% and there are additional patient variables that can increase this. The feasibility of weighing the pump rather than a visual inspection along with the secondary objective to confirm the pump's variability in real world conditions was undertaken. Methods Empty pumps were weighed using both pharmacy and kitchen scales. Pumps upon completion of the 46-h infusion were also weighed using both pharmacy and kitchen scales. Results The kitchen scale was as accurate as the pharmacy grade scale. Disconnected pumps showed the expected variability from using these infusor pumps along with a few showing greater variability likely due to patient variables. Conclusion Weighing pumps appears to be feasible both at the pharmacy and home level. Next steps would be to weigh pumps during the infusion to validate an alternate method to simple visual inspection for patients to confirm proper infusing of the pump at their home.

Experimental Realization of a Quantum Spin Pump

DEFF Research Database (Denmark)

Watson, Susan; Potok, R.; M. Marcus, C.

2003-01-01

We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin-dependent by the a......We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin......-dependent by the application of an in-plane Zeeman field. Spin currents are measured by placing the pump in a focusing geometry with a spin-selective collector....

Multidrug Efflux Pumps in Staphylococcus aureus: an Update

OpenAIRE

Costa, Sofia Santos; Viveiros, Miguel; Amaral, Leonard; Couto, Isabel

2013-01-01

The emergence of infections caused by multi- or pan-resistant bacteria in the hospital or in the community settings is an increasing health concern. Albeit there is no single resistance mechanism behind multiresistance, multidrug efflux pumps, proteins that cells use to detoxify from noxious compounds, seem to play a key role in the emergence of these multidrug resistant (MDR) bacteria. During the last decades, experimental data has established their contribution to low level resistance to an...

Residual heat removal pump retrofit program

International Nuclear Information System (INIS)

Dudiak, J.G.; McKenna, J.M.

1990-01-01

Residual Heat Removal (RHR) pumps installed in pressurized water reactor power plants are used to provide the removal of decay heat from the reactor and to provide low head safety injection in the event of loss of coolant in the reactor coolant system. These pumps are subjected to rather severe temperature and pressure transients, therefore, the majority of pumps installed in the RHR service are vertical pumps with a single stage impeller. RHR pumps have traditionally been a significant maintenance item for many utilities. The close-coupled pump design requires disassembly of the casing cover from the lower pump casing while performing these routine maintenance tasks. The casing separation requires the loosening of numerous highly torqued studs. Once the casing is separated, the impeller is dropped from the motor shaft to allow removal of the mechanical seal and casing cover from the motor shaft. Galling of the impeller to the motor shaft is not uncommon. The RHR pump internals are radioactive and the separation of the pump casing to perform routine maintenance exposes the maintenance personnel to high radiation levels. The handling of the impeller also exposes the maintenance personnel to high radiation levels. This paper introduces a design modification developed to convert the close-coupled RHR pumps to a coupled configuration

XFEL resonant photo-pumping of dense plasmas and dynamic evolution of autoionizing core hole states

OpenAIRE

Rosmej, F. B.; Moinard, A.; Renner, O.; Galtier, E.; Lee, J. J.; Nagler, B.; Heimann, P. A.; Schlotter, W.; Turner, J. J.; Lee, R. W.; Makita, M.; Riley, D.; Seely, J.

2016-01-01

Similarly to the case of LIF (Laser-Induced Fluorescence), an equally revolutionary impact to science is expected from resonant X-ray photo-pumping. It will particularly contribute to a progress in high energy density science: pumped core hole states create X-ray transitions that can escape dense matter on a 10 fs-time scale without essential photoabsorption, thus providing a unique possibility to study matter under extreme conditions. In the first proof of principle experiment at the X-ray F...

Analysis of the pump-beam path in corner-pumped slab laser

International Nuclear Information System (INIS)

Chen Li; Qiang Liu; Mali Gong; Gang Chen; Ping Yan

2007-01-01

The propagation of the pump radiation in active slab elements is considered. Conditions of the total internal reflection of the pump radiation are obtained, and are used to construct a series of graphical illustrations of reflection characteristics of different active elements. (control of laser radiation parameters)

Nano-electro-mechanical pump: Giant pumping of water in carbon nanotubes

Science.gov (United States)

Farimani, Amir Barati; Heiranian, Mohammad; Aluru, Narayana R.

2016-05-01

A fully controllable nano-electro-mechanical device that can pump fluids at nanoscale is proposed. Using molecular dynamics simulations, we show that an applied electric field to an ion@C60 inside a water-filled carbon nanotube can pump water with excellent efficiency. The key physical mechanism governing the fluid pumping is the conversion of electrical energy into hydrodynamic flow with efficiencies as high as 64%. Our results show that water can be compressed up to 7% higher than its bulk value by applying electric fields. High flux of water (up to 13,000 molecules/ns) is obtained by the electro-mechanical, piston-cylinder-like moving mechanism of the ion@C60 in the CNT. This large flux results from the piston-like mechanism, compressibility of water (increase in density of water due to molecular ordering), orienting dipole along the electric field and efficient electrical to mechanical energy conversion. Our findings can pave the way towards efficient energy conversion, pumping of fluids at nanoscale, and drug delivery.

Human Aorta Is a Passive Pump

Science.gov (United States)

Pahlevan, Niema; Gharib, Morteza

2012-11-01

Impedance pump is a simple valveless pumping mechanism that operates based on the principles of wave propagation and reflection. It has been shown in a zebrafish that a similar mechanism is responsible for the pumping action in the embryonic heart during early stages before valve formation. Recent studies suggest that the cardiovascular system is designed to take advantage of wave propagation and reflection phenomena in the arterial network. Our aim in this study was to examine if the human aorta is a passive pump working like an impedance pump. A hydraulic model with different compliant models of artificial aorta was used for series of in-vitro experiments. The hydraulic model includes a piston pump that generates the waves. Our result indicates that wave propagation and reflection can create pumping mechanism in a compliant aorta. Similar to an impedance pump, the net flow and the flow direction depends on the frequency of the waves, compliance of the aorta, and the piston stroke.

Sludge pumping in water treatment

International Nuclear Information System (INIS)

Solar Manuel, M. A.

2010-01-01

In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

Vivitron dead section pumping tests

International Nuclear Information System (INIS)

Heugel, J.; Bayet, J.P.; Brandt, C.; Delhomme, C.; Krieg, C.; Kustner, F.; Meiss, R.; Riehl, R.; Roth, C.; Schlewer, B.; Six, P.; Weber, A.

1990-10-01

Pumping tests have been conducted on a simulated accelerator dead section. The behavior of different pump types are compared and analyzed. Vacuum conditions to be expected in the Vivitron are reached and several parameters are verified. Selection of a pump for the Vivitron dead section is confirmed

Cryogenic storage tank with built-in pump

International Nuclear Information System (INIS)

Zwick, E.B.

1984-01-01

A cryogenic storage tank with a built-in pump for pumping cryogen directly from the primary storage container consistent with low boil-off losses of cryogen has an outer vessel, an inner vessel and an evacuated insulation space therebetween. A pump mounting tube assembly extends into the interior of the inner vessel and includes an inner pump mounting tube and an outer pump mounting tube joined at their lower rims to define an insulating jacket between the two tubes. The inner pump mounting tube is affixed at its upper end to the outer vessel while the outer pump mounting tube is affixed at its upper end to the inner vessel. The inner pump mounting tube defines a relatively long heat path into the cryogenic container and is itself insulated from the liquid cryogen by a pocket of trapped gas formed within the inner pump mounting tube by heated cryogen. A pump may be introduced through the inner pump mounting tube and is also insulated against contact with liquid cryogen by the trapped gas such that only the lowermost end of the pump is immersed in cryogen thereby minimizing heat leakage into the tank

14 CFR 25.991 - Fuel pumps.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel pumps. 25.991 Section 25.991... STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Fuel System Components § 25.991 Fuel pumps. (a) Main pumps. Each fuel pump required for proper engine operation, or required to meet the fuel system...

Design of liquid lithium pumps for FMIT

International Nuclear Information System (INIS)

Adkins, H.E.

1983-01-01

In the Fusion Materials Irradiation Test (FMIT) facility, a jet of liquid lithium is bombarded by accelerated deuterons to generate high energy neutrons for materials testing. The lithium system will include two electromagnetic pumps, a 750 gpm main pump and a 10 gpm auxiliary pump. The larger pump was designed and built in 1982, following extensive testing of a similar pump in the Experimental Lithium System. Design of the auxiliary pump has been completed, but fabrication has not started. This paper discusses the design considerations leading to selection of the Annular Linear Induction Pump (ALIP) concept for these applications. Design parameters, fabrication procedures, and results of pump testing are also reviewed

Gas fired heat pumps

International Nuclear Information System (INIS)

Seifert, M.

2006-01-01

The condensing gas boiler is now state of the art and there is no more room for improvement in performance, technically speaking. The next logical step to improve the overall efficiency is to exploit ambient heat in combination with the primary source of energy, natural gas. That means using natural-gas driven heat pumps and gas-fired heat pumps. Based on this, the Swiss Gas Industry decided to set up a practical test programme enjoying a high priority. The aim of the project 'Gas-fired heat pump practical test' is to assess by field tests the characteristics and performance of the foreign serial heat pumps currently on the market and to prepare and promote the introduction on the market place of this sustainable natural-gas technology. (author)

Time-resolved pump-probe experiments at the LCLS

Energy Technology Data Exchange (ETDEWEB)

Glownia, James; /SLAC /Stanford U., Appl. Phys. Dept.; Cryan, J.; /SLAC /Stanford U., Phys. Dept.; Andreasson, J.; /Uppsala U.; Belkacem, A.; /LBNL, Berkeley; Berrah, N.; /Western Michigan U.; Blaga, C.L.; /Ohio State U.; Bostedt, C.; Bozek, J.; /SLAC; DiMauro, L.F.; /Ohio State U.; Fang, L.; /Western Michigan U.; Frisch, J.; /SLAC; Gessner, O.; /LBNL; Guhr, M.; /SLAC; Hajdu, J.; /Uppsala U.; Hertlein, M.P.; /LBNL; Hoener, M.; /Western Michigan U. /LBNL; Huang, G.; Kornilov, O.; /LBNL; Marangos, J.P.; /Imperial Coll., London; March, A.M.; /Argonne; McFarland, B.K.; /SLAC /Stanford U., Phys. Dept. /SLAC /IRAMIS, Saclay /Stanford U., Phys. Dept. /Georgia Tech /Argonne /Kansas State U. /SLAC /Stanford U., Phys. Dept. /SLAC /Stanford U., Appl. Phys. Dept. /Stanford U., Appl. Phys. Dept. /SLAC /LBNL /Argonne /SLAC /SLAC /Stanford U., Appl. Phys. Dept. /Stanford U., Phys. Dept.

2011-08-12

The first time-resolved x-ray/optical pump-probe experiments at the SLAC Linac Coherent Light Source (LCLS) used a combination of feedback methods and post-analysis binning techniques to synchronize an ultrafast optical laser to the linac-based x-ray laser. Transient molecular nitrogen alignment revival features were resolved in time-dependent x-ray-induced fragmentation spectra. These alignment features were used to find the temporal overlap of the pump and probe pulses. The strong-field dissociation of x-ray generated quasi-bound molecular dications was used to establish the residual timing jitter. This analysis shows that the relative arrival time of the Ti:Sapphire laser and the x-ray pulses had a distribution with a standard deviation of approximately 120 fs. The largest contribution to the jitter noise spectrum was the locking of the laser oscillator to the reference RF of the accelerator, which suggests that simple technical improvements could reduce the jitter to better than 50 fs.

How efficient are heat pumps? Investigations in practical operation; Wie effizient sind Waermepumpen? Messungen im Praxisbetrieb

Energy Technology Data Exchange (ETDEWEB)

Miara, Marek [Fraunhofer ISE, Freiburg (Germany)

2010-11-15

Heat pump systems win ever larger market shares within the range of the heating and hot water preparation in buildings. But, how great is their efficiency in the practical operation? What are the factors which affect the efficiency? In order to evaluate the ecological, energetic and economic criteria better, Fraunhofer ISE (Freiburg, Federal Republic of Germany) has investigated nearly two hundred heat pump systems scientifically. The contribution under consideration summarizes the most current results and the most important realizations.

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.)

High temperature industrial heat pumps

Energy Technology Data Exchange (ETDEWEB)

Berghmans, J. (Louvain Univ., Heverlee (Belgium). Inst. Mechanica)

1990-01-01

The present report intends to describe the state of the art of high temperature industrial heat pumps. A description is given of present systems on the market. In addition the research and development efforts on this subject are described. Compression (open as well as closed cycle) systems, as well as absorption heat pumps (including transformers), are considered. This state of the art description is based upon literature studies performed by a team of researchers from the Katholieke Universiteit Leuven, Belgium. The research team also analysed the economics of heat pumps of different types under the present economic conditions. The heat pumps are compared with conventional heating systems. This analysis was performed in order to evaluate the present condition of the heat pump in the European industry.

Cryosorption vacuum pumping under fusion reactor conditions

International Nuclear Information System (INIS)

Watson, J.S.; Fisher, P.W.

1977-01-01

Experiments are in progress on cryosorption pumping using a double-chevron pump with a molecular sieve pumping surface. Studies have been made with hydrogen, deuterium, helium, and deuterium-helium at 10 -7 to 3 x 10 -3 torr. Steady pumping speeds were observed for deuterium; above 10 -4 torr the speed increased with pressure until runaway occurred. At less than 10 -6 torr and low panel loading, hydrogen pumping speeds resemble those for deuterium. At higher pressures, the pump can function by condensation or sorption, and unsteady speeds are observed. Helium pumping is always by sorption, but regions of instability have been observed and defined. Deuterium-helium pumping tests showed that deuterium condensation on the panels prevents cryosorption of helium; however, compound pumps with separate panels for helium and hydrogen will be satisfactory

Heat driven pulse pump

Science.gov (United States)

Benner, Steve M (Inventor); Martins, Mario S. (Inventor)

2000-01-01

A heat driven pulse pump includes a chamber having an inlet port, an outlet port, two check valves, a wick, and a heater. The chamber may include a plurality of grooves inside wall of the chamber. When heated within the chamber, a liquid to be pumped vaporizes and creates pressure head that expels the liquid through the outlet port. As liquid separating means, the wick, disposed within the chamber, is to allow, when saturated with the liquid, the passage of only liquid being forced by the pressure head in the chamber, preventing the vapor from exiting from the chamber through the outlet port. A plurality of grooves along the inside surface wall of the chamber can sustain the liquid, which is amount enough to produce vapor for the pressure head in the chamber. With only two simple moving parts, two check valves, the heat driven pulse pump can effectively function over the long lifetimes without maintenance or replacement. For continuous flow of the liquid to be pumped a plurality of pumps may be connected in parallel.

Part-load pumping operation, control and behaviour

International Nuclear Information System (INIS)

1988-01-01

Twenty one papers are printed. Their main concern is with pump performance under abnormal operating conditions or when operating at part-load. The effect of part-load operation on pump performance, pump internal flow and pump cavitation and noise were considered. The pumps considered are used in a variety of situations and some case studies were discussed. One paper about part-load operation of the boiler pumps for French pressurized water reactors and one paper on pressure pulsations of centrifugal pumps at very low flowrate, are indexed separately. (U.K.)

Gas heat pump in the school and sport centre of Altenkunstadt

Energy Technology Data Exchange (ETDEWEB)

Tscherter, F [Ferngas Nordbayern G.m.b.H., Bamberg (Germany, F.R.)

1978-01-01

Illustrated by a concrete example of a plant in operation, it is shown how the heat potential of river water can be utilized extensively for hot water preparation and space heating when using a heat pump. The plant has operated successfully since October 1977 and makes a valuable contribution to efficient use of energy on the heating sector.

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)

46 CFR 182.520 - Bilge pumps.

Science.gov (United States)

2010-10-01

...) Highly resistant to salt water, petroleum oil, heat, and vibration. (g) If a fixed hand pump is used to... GPM). (b) A portable hand bilge pump must be: (1) Capable of pumping water, but not necessarily..., including wiring, and size and number of batteries, is designed to allow all bilge pumps to be operated...

46 CFR 105.20-10 - Pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Pumps. 105.20-10 Section 105.20-10 Shipping COAST GUARD... DISPENSING PETROLEUM PRODUCTS Specific Requirements-Cargo Tanks § 105.20-10 Pumps. (a) Pumps for cargo... discharge side of pump if the pressure under shutoff conditions exceeds 60 pounds. When a relief valve is...

High Speed Pump-Probe Apparatus for Observation of Transitional Effects in Ultrafast Laser Micromachining Processes

Directory of Open Access Journals (Sweden)

Ilya Alexeev

2015-12-01

Full Text Available A pump-probe experimental approach has been shown to be a very efficient tool for the observation and analysis of various laser matter interaction effects. In those setups, synchronized laser pulses are used to create an event (pump and to simultaneously observe it (probe. In general, the physical effects that can be investigated with such an apparatus are restricted by the temporal resolution of the probe pulse and the observation window. The latter can be greatly extended by adjusting the pump-probe time delay under the assumption that the interaction process remains fairly reproducible. Unfortunately, this assumption becomes invalid in the case of high-repetition-rate ultrafast laser material processing, where the irradiation history strongly affects the ongoing interaction process. In this contribution, the authors present an extension of the pump-probe setup that allows to investigate transitional and dynamic effects present during ultrafast laser machining performed at high pulse repetition frequencies.

46 CFR 181.300 - Fire pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Fire pumps. 181.300 Section 181.300 Shipping COAST GUARD... EQUIPMENT Fire Main System § 181.300 Fire pumps. (a) A self priming, power driven fire pump must be..., the minimum capacity of the fire pump must be 189 liters (50 gallons) per minute at a pressure of not...

46 CFR 118.300 - Fire pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire pumps. 118.300 Section 118.300 Shipping COAST GUARD... Fire pumps. (a) A self priming, power driven fire pump must be installed on each vessel. (b) On a..., the fire pump must be capable of delivering a single hose stream from the highest hydrant, through the...

46 CFR 169.559 - Fire pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Fire pumps. 169.559 Section 169.559 Shipping COAST GUARD... Firefighting Equipment Firefighting Equipment § 169.559 Fire pumps. (a) Each sailing school vessel must be equipped with fire pumps as required in Table 169.559(a). Table 169.559(a)—Fire Pumps Length Exposed and...

Development of ANC-type empirical two-phase pump model for full size CANDU primary heat transport pump

International Nuclear Information System (INIS)

Chan, A.M.C.; Huynh, H.M.

2004-01-01

The development of an ANC-type empirical two-phase pump model for CANDU (Canadian Deuterium) reactor primary heat transport pumps is described in the present paper. The model was developed based on Ontario Hydro Technologies' full scale Darlington pump first quadrant test data. The functional form of the ANC model which is widely used was chosen to facilitate the implementation of the model into existing computer codes. The work is part of a bigger test program with the aims: (1) to produce high quality pump performance data under off-normal operating conditions using both full-size and model scale pumps; (2) to advance our basic understanding of the dominant mechanisms affecting pump performance based on more detailed local measurements; and (3) to develop a 'best-estimate' or improved pump model for use in reactor licensing and safety analyses. (author)

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

Peristaltic pumps for waste disposal

International Nuclear Information System (INIS)

Griffith, G.W.

1992-09-01

Laboratory robots are capable of generating large volumes of hazardous liquid wastes when they are used to perform chemical analyses of metal finishing solutions. A robot at Allied-Signal Inc., Kansas City Division, generates 30 gallons of acid waste each month. This waste contains mineral acids, heavy metals, metal fluorides, and other materials. The waste must be contained in special drums that are closed to the atmosphere. The initial disposal method was to have the robot pour the waste into a collecting funnel, which contained a liquid-sensing valve to admit the waste into the drum. Spills were inevitable, splashing occurred, and the special valve often didn't work well. The device also occupied a large amount of premium bench space. Peristaltic pumps are made to handle hazardous liquids quickly and efficiently. A variable-speed pump, equipped with a quick-loading pump head, was mounted below the robot bench near the waste barrel. The pump inlet tube was mounted above the bench within easy reach of the robot, while the outlet tube was connected directly to the barrel. During operation, the robot brings the waste liquid up to the pump inlet tube and activates the pump. When the waste has been removed, the pump stops. The procedure is quick, simple, inexpensive, safe, and reliable

High Voltage Charge Pump

KAUST Repository

Emira, Ahmed A.; Abdelghany, Mohamed A.; Elsayed, Mohannad Yomn; Elshurafa, Amro M; Salama, Khaled N.

2014-01-01

Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

High Voltage Charge Pump

KAUST Repository

Emira, Ahmed A.

2014-10-09

Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

Substrate specificities and efflux efficiencies of RND efflux pumps of Acinetobacter baumannii.

Science.gov (United States)

Leus, Inga V; Weeks, Jon W; Bonifay, Vincent; Smith, Lauren; Richardson, Sophie; Zgurskaya, Helen I

2018-04-16

Antibiotic resistant Acinetobacter baumannii causes infections that are extremely difficult to treat. A significant role in these resistance profiles is attributed to multidrug efflux pumps, especially those belonging to Resistance-Nodulation-cell Division (RND) superfamily of transporters. In this study, we analyzed functions and properties of RND efflux pumps in A. baumannii ATCC 17978. This strain is susceptible to antibiotics and does not contain mutations that are commonly selected upon exposure to high concentrations of antibiotics. We constructed derivatives of ATCC 17978 lacking chromosomally encoded RND pumps and complemented these strains by the plasmid-borne genes. We analyzed the substrate selectivities and efficiencies of the individual pumps in the context of native outer membranes and their hyperporinated variants. Our results show that inactivation of AdeIJK provides the strongest potentiation of antibiotic activities, whereas inactivation of AdeFGH triggers the overexpression of AdeAB. The plasmid-borne overproduction complements the hypersusceptible phenotypes of the efflux deletion mutants to the levels of the parental ATCC 17978. Only a few antibiotics strongly benefitted from the overproduction of efflux pumps and antibacterial activities of some of those depended on the synergistic interaction with the low permeability barrier of the outer membrane. Either overproduction or inactivation of efflux pumps change dramatically the lipidome of ATCC 17978. We conclude that efflux pumps of A. baumannii are tightly integrated into physiology of this bacterium and that clinical levels of antibiotic resistance in A. baumannii isolates are unlikely to be reached solely due to overproduction of RND efflux pumps. Importance RND-type efflux pumps are important contributors in development of clinical antibiotic resistance in A. baumannii However, their specific roles and the extent of contribution to antibiotic resistance remain unclear. We analyzed

Drug delivery device including electrolytic pump

KAUST Repository

Foulds, Ian G.; Buttner, Ulrich; Yi, Ying

2016-01-01

Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

Capillary-Condenser-Pumped Heat-Transfer Loop

Science.gov (United States)

Silverstein, Calvin C.

1989-01-01

Heat being transferred supplies operating power. Capillary-condenser-pumped heat-transfer loop similar to heat pipe and to capillary-evaporator-pumped heat-transfer loop in that heat-transfer fluid pumped by evaporation and condensation of fluid at heat source and sink, respectively. Capillary condenser pump combined with capillary evaporator pump to form heat exchanger circulating heat-transfer fluids in both loops. Transport of heat more nearly isothermal. Thermal stress in loop reduced, and less external surface area needed in condenser section for rejection of heat to heat sink.

Drug delivery device including electrolytic pump

KAUST Repository

Foulds, Ian G.

2016-03-31

Systems and methods are provided for a drug delivery device and use of the device for drug delivery. In various aspects, the drug delivery device combines a “solid drug in reservoir” (SDR) system with an electrolytic pump. In various aspects an improved electrolytic pump is provided including, in particular, an improved electrolytic pump for use with a drug delivery device, for example an implantable drug delivery device. A catalytic reformer can be incorporated in a periodically pulsed electrolytic pump to provide stable pumping performance and reduced actuation cycle.

Quantifying the energy impact of a variable flow pump in a ground-coupled heat pump system

Energy Technology Data Exchange (ETDEWEB)

Iolova, K.; Bernier, M.A. [Ecole Polytechnique, Montreal, PQ (Canada). Dept. de Genie Mecanique; Nichols, L. [Dessau-Soprin, Montreal, PQ (Canada)

2006-07-01

The thermal behaviour of an energy-efficient public high school building was modelled using the TRNSYS multi-zone building simulation program. The architectural elements such as windows, external and internal walls, roofs, and slabs were described in detail. The two-storey Ecole du Tournant high school near Montreal is the most efficient in Quebec and the second in Canada. It consumes 79.2 per cent less source energy than a typical high school built in accordance with the Model National Energy Code of Canada for Buildings. This presentation described the case study and quantified the energy impact of replacing a constant speed pump with a pump driven by a variable frequency drive in a ground-coupled heat pump (GCHP) system that was installed in the high school. Performance data collected from an on-site energy management system showed that the annual energy consumption of the heat pumps is 33 per cent (63700 kWh) of the total energy consumption of the school while the circulating pump consumes 7.1 per cent (13702 kWh). This performance data was used to validate the energy simulations which were performed using TRNSYS 15. Simulations with variable-flow pumping showed that pumping energy consumption was reduced by about 82 per cent while the total energy used by the circulating pump and heat pumps was reduced by 18.5 per cent. 11 refs., 2 tabs., 13 figs.

Nuclear power plant safety related pump issues

Energy Technology Data Exchange (ETDEWEB)

Colaccino, J.

1996-12-01

This paper summarizes of a number of pump issues raised since the Third NRC/ASME Symposium on Valve and Pump Testing in 1994. General issues discussed include revision of NRC Inspection Procedure 73756, issuance of NRC Information Notice 95-08 on ultrasonic flow meter uncertainties, relief requests for tests that are determined by the licensee to be impractical, and items in the ASME OM-1995 Code, Subsection ISTB, for pumps. The paper also discusses current pump vibration issues encountered in relief requests and plant inspections - which include smooth running pumps, absolute vibration limits, and vertical centrifugal pump vibration measurement requirements. Two pump scope issues involving boiling water reactor waterlog and reactor core isolation cooling pumps are also discussed. Where appropriate, NRC guidance is discussed.

Nuclear power plant safety related pump issues

International Nuclear Information System (INIS)

Colaccino, J.

1996-01-01

This paper summarizes of a number of pump issues raised since the Third NRC/ASME Symposium on Valve and Pump Testing in 1994. General issues discussed include revision of NRC Inspection Procedure 73756, issuance of NRC Information Notice 95-08 on ultrasonic flow meter uncertainties, relief requests for tests that are determined by the licensee to be impractical, and items in the ASME OM-1995 Code, Subsection ISTB, for pumps. The paper also discusses current pump vibration issues encountered in relief requests and plant inspections - which include smooth running pumps, absolute vibration limits, and vertical centrifugal pump vibration measurement requirements. Two pump scope issues involving boiling water reactor waterlog and reactor core isolation cooling pumps are also discussed. Where appropriate, NRC guidance is discussed

High reliability flow system - an assessment of pump reliability and optimisation of the number of pumps

International Nuclear Information System (INIS)

Butterfield, J.M.

1981-01-01

A system is considered where a number of pumps operate in parallel. Normally, all pumps operate, driven by main motors fed from the grid. Each pump has a pony motor fed from an individual battery supply. Each pony motor is normally running, but not engaged to the pump shaft. On demand, e.g. failure of grid supplies, each pony motor is designed to clutch-in automatically when the pump speed falls to a specified value. The probability of all the pony motors failing to clutch-in on demand must be demonstrated with 95% confidence to be less than 10 -8 per demand. This assessment considers how the required reliability of pony motor drives might be demonstrated in practice and the implications on choice of the number of pumps at the design stage. The assessment recognises that not only must the system prove to be extremely reliable, but that demonstration that reliability is adequate must be done during plant commissioning, with practical limits on the amount of testing performed. It is concluded that a minimum of eight pony motors should be provided, eight pumps each with one pony motor (preferred) or five pumps each with two independent pony motors. A minimum of two diverse pony motor systems should be provided. (author)

The effect of pump cavitation on the design of the primary pumps for C.F.R

International Nuclear Information System (INIS)

Worster, R.C.

1976-01-01

In the design appraisal of the sodium pumps for the primary circuit of the proposed 1300 MW(e) CFR it has been recognised that cavitation, its effects and its control, is the outstanding hydraulic design problem. Careful consideration of this problem and of the possible effects of pump cavitation on the performance of other reactor systems has led to the conclusion that it is more prudent at present to specify pumps with zero cavitation at normal full speed operating conditions. Under abnormal operation it may be necessary to reduce the pumps' speed to prevent cavitation in the pumps or associated equipment. The principal reasons for this decision were uncertainties concerning the possibility of erosion due to limited cavitation in sodium and the possibility of pump cavitation noise interfering with acoustic detection of malfunctioning of reactor components or of boiling in the reactor core

Design of Pumps for Water Hydraulic Systems

DEFF Research Database (Denmark)

Klit, Peder; Olsen, Stefan; Bech, Thomas Nørgaard

1999-01-01

This paper considers the development of two pumps for water hydraulic applications. The pumps are based on two different working principles: The Vane-type pump and the Gear-type pump. Emphasis is put on the considerations that should be made to account for water as the hydraulic fluid.......KEYWORDS: water, pump, design, vane, gear....

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

A study of waste and delivery valve design modification to the pump performance

Science.gov (United States)

Harith, M. N.; Bakar, R. A.; Ramasamy, D.; Kardigama, K.; Quanjin, Ma

2018-04-01

This paper objective is to share design revolution of waste and delivery valve that contribute to the overall pump performance. In this paper, 3 new designs of waste and delivery valve pump are presented with comprehensive internal flow analysis using computational fluid dynamics (CFD) simulation over 4 cases that have been deeply study for one of the design chosen. 4 cases involving opening and closing both valve or either one. 0.265m height size of customized waste valve with an opening limiter and spring was used to demonstrate cyclic closing and opening valve operation extended up to 0.164m gap. Based on result, this characteristics contribute to 10-20% waste water reduction and enhancement of flow rate height up to 80m. Apart from that this paper also share some of pressure (dynamic, total, static), velocity (x, y, z axis) simulation including the vector flow were under different flow cases.

Influence of individual heat pumps on wind power integration – Energy system investments and operation

International Nuclear Information System (INIS)

Hedegaard, Karsten; Münster, Marie

2013-01-01

Highlights: • Individual heat pumps can significantly support the integration of wind power. • The heat pumps significantly reduce fuel consumption, CO 2 emissions, and costs. • Heat storages for the heat pumps can provide only moderate system benefits. • Main benefit of flexible heat pump operation is a lower peak/reserve capacity need. • Socio-economic feasibility only identified for some heat storages to some extent. - Abstract: Individual heat pumps are expected to constitute a significant electricity demand in future energy systems. This demand becomes flexible if investing in complementing heat storage capabilities. In this study, we analyse how the heat pumps can influence the integration of wind power by applying an energy system model that optimises both investments and operation, and covers various heat storage options. The Danish energy system by 2030 with around 50–60% wind power is used as a case study. Results show that the heat pumps, even without flexible operation, can contribute significantly to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO 2 emissions. Investments in heat storages can provide only moderate system benefits in these respects. The main benefit of the flexible heat pump operation is a reduced need for peak/reserve capacity, which is also crucial for the feasibility of the heat storages. Socio-economic feasibility is identified for control equipment enabling intelligent heat storage in the building structure and in existing hot water tanks. In contrast, investments in new heat accumulation tanks are not found competitive

Measurements on a PV solar pump equipped with a piston pump with a matching valve

NARCIS (Netherlands)

Smulders, P.T.; Ten Thije O.G. Boonkkamp, J.; Borg, van der N.J.C.M.; Beek, van M.

1997-01-01

The work on a simple high efficient solar pump equipped with a piston pump with a matching valve, reported at the Solar World Congress in Budapest, has been continued. Quasi-static and dynamic models of the solar pump have been derived with which the operation of the system is simulated. A test rig

Using NEG-pumping near a high density internal target

International Nuclear Information System (INIS)

Gruber, A.; Marton, J.; Widmann, E.; Zmeskal, J.; Orth, H.

2008-01-01

Full text: The Stefan Meyer Institut (SMI) is part of the international PANDA collaboration. The universal detector will be constructed at the future high-energy antiproton storage ring HESR at FAIR (Facility for Antiproton and Ion Research, GSI/Darmstadt). PANDA will use antiproton beams (1.5 to 15 GeV/c) for hadron physics in the charmonium region. SMI contributes to major parts of the PANDA detector like the hydrogen cluster-jet target and the vacuum system of the antiproton - target interaction zone. To ensure low background, the residual gas load in the interaction zone and in the antiproton beam-pipe has to be minimized. Most of the gas load, of course will come from the high density internal hydrogen target. Since the PANDA detector will cover almost the full solid angle, the installation of pumps near the interaction zone is impossible. Therefore, the use of NEG (non-evaporative-getter) coated beam pipes has been considered as an alternative. Two setups with NEG coated tubes have been installed at SMI as prototypes of the PANDA interaction zone. The outgassing behavior, the pumping speed and the pumping capacity for hydrogen have been tested. The status of the studies of the interaction region will be presented. (author)

Heat pumps are a dream

Energy Technology Data Exchange (ETDEWEB)

1981-12-01

The fact that heat pumps do not achieve what their manufacturers promise in costs efficiency has been realized by the market. In 1981 the sales of heat pumps decreased by 50% of the 1980 market. Public utilities give the reason as economic, since fuel oil is too cheap. The author refutes this argument and presents arguments against heat pumps.

Direct solar-pumped iodine laser amplifier

Science.gov (United States)

Han, Kwang S.

1987-01-01

This semiannual progress report covers the period from March 1, 1987 to September 30, 1987 under NASA grant NAG1-441 entitled 'Direct solar-pumped iodine laser amplifier'. During this period Nd:YAG and Nd:Cr:GSGG crystals have been tested for the solar-simulator pumped cw laser, and loss mechanisms of the laser output power in a flashlamp-pumped iodine laser also have been identified theoretically. It was observed that the threshold pump-beam intensities for both Nd:YAG and Nd:Cr:GSGG crystals were about 1000 solar constants, and the cw laser operation of the Nd:Cr:GSGG crystal was more difficult than that of the Nd:YAG crystal under the solar-simulator pumping. The possibility of the Nd:Cr:GSGG laser operation with a fast continuously chopped pumping was also observed. In addition, good agreement between the theoretical calculations and the experimental data on the loss mechanisms of a flashlamp-pumped iodine laser at various fill pressures and various lasants was achieved.

Removal of mixing pump in tank 102-AP -- pump drop onto central pit

International Nuclear Information System (INIS)

Jimenez, R.F.

1995-01-01

The mixing pump, if dropped in the pump pit following its removal from the tank, is incapable of compromising the tank structure either locally or in a structural displacement mode to an extent which might allow dispersion of the contents. A drop from 10 ft above the pit floor (considered the maximum credible height) of a pump which is considered perfectly rigid does not approach the required perforation velocity. The velocity required to perforate requires a drop height which is physically impossible to attain with existing cranes. An analysis of the location of the deposition of the strain energy required to match the pump's impact kinetic energy, the results of which are shown in Table 2, verifies that there is no credible chance for compromise of the tank roof by such a drop

Wind power integration with heat pumps, heat storages, and electric vehicles – Energy systems analysis and modelling

DEFF Research Database (Denmark)

Hedegaard, Karsten

The fluctuating and only partly predictable nature of wind challenges an effective integration of large wind power penetrations. This PhD thesis investigates to which extent heat pumps, heat storages, and electric vehicles can support the integration of wind power. Considering the gaps in existing...... in an energy system context. Energy systems analyses reveal that the heat pumps can even without flexible operation contribute significantly to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO2 emissions. When equipping the heat pumps with heat storages, only...... moderate additional benefits are achieved. Hereof, the main benefit is that the need for investing in peak/reserve capacities can be reduced through peak load shaving. It is more important to ensure flexible operation of electric vehicles than of individual heat pumps, due to differences in the load...

Proper Sizing of Circulation Pumps

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Nørgaard, Jørgen

2007-01-01

The paper describes the preliminary results from field tests of replacing various types of old pumps used for circulating water in heating systems in single- and double-family houses with new types of pumps. The tests were carried out in Denmark for the Danish Electricity Savings Trust, but the r......The paper describes the preliminary results from field tests of replacing various types of old pumps used for circulating water in heating systems in single- and double-family houses with new types of pumps. The tests were carried out in Denmark for the Danish Electricity Savings Trust...

Contribution of efflux pumps in fluroquinolone resistance in multi-drug resistant nosocomial isolates of Pseudomanas aeruginosa from a tertiary referral hospital in north east India

Directory of Open Access Journals (Sweden)

D Choudhury

2015-01-01

Full Text Available Background: Pseudomonas aeruginosa is one of the leading opportunistic pathogen and its ability to acquire resistance against series of antimicrobial agents confine treatment option for nosocomial infections. Increasing resistance to fluroquinolone (FQ agents has further worsened the scenario. The major mechanism of resistance to FQs includes mutation in FQs target genes in bacteria (DNA gyrase and/or topoisomerases and overexpression of antibiotic efflux pumps. Objective: We have investigated the role of efflux pump mediated FQ resistance in nosocomial isolates of P. aeruginosa from a tertiary referral hospital in north eastern part of India. Materials and Methods: A total of 234 non-duplicate, consecutive clinical isolates of P. aeruginosa were obtained from a tertiary referral hospital of north-east India. An efflux pump inhibitor (EPI, carbonyl cyanide m-chlorophenylhydrazone (CCCP based method was used for determination of efflux pump activity and multiplex polymerase chain reaction (PCR was performed for molecular characterisation of efflux pump. Minimum inhibitory concentration (MIC reduction assay was also performed for all the isolates. Results and Conclusion: A total number of 56 (23% have shown efflux mediated FQ resistance. MexAB-OprM efflux system was predominant type. This is the first report of efflux pump mediated FQ resistance from this part of the world and the continued emergence of these mutants with such high MIC range from this part of the world demands serious awareness, diagnostic intervention, and proper therapeutic option.

Alignment analysis of a vertical sodium pump

International Nuclear Information System (INIS)

Gupta, V.K.; Fair, C.E.

1981-01-01

With the objective of identifying important alignment features of pumps such as FFTF, HALLAM, EBR II, PNC, PHENIX, and CRBR, alignment of the vertical sodium pump for the Clinch River Breeder Reactor Plant (CRBRP) is investigated. The CRBRP pump includes a flexibly coupled pump shaft and motor shaft, two oil-film tilting-pad hydrodynamic radial bearings in the motor plus a vertical thrust bearing, and two sodium hydrostatic bearings straddling the double-suction centrifugal impeller in the pump. The assembled CRBRP prototype pump shows smooth predictable vibration behavior experienced during water test. An ealier swing check of the pump shaft about the motor shaft hub demonstrated that the pump is relatively insensitive to manufacturing and assembly tolerances, a consequence of close dimensional control and unique alignment features. (orig./GL)

Compact and highly efficient laser pump cavity

Science.gov (United States)

Chang, Jim J.; Bass, Isaac L.; Zapata, Luis E.

1999-01-01

A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

Pumped storage

International Nuclear Information System (INIS)

Strauss, P.L.

1991-01-01

The privately financed 1,000 MW Rocky Point Pumped Storage Project located in central Colorado, USA, will be one of the world's highest head, 2,350 feet reversible pump/turbine projects. The project will offer an economical supply of peaking power and spinning reserve power to Colorado and other southwestern states. This paper describes how the project will be made compatible with the environmental conditions in the project area and the type of terrestrial mitigation measures that are being proposed for those situations where the project impacts the environment, either temporarily or permanently

An optimized design of rectangle pumping cell for nuclear reactor pumped laser

International Nuclear Information System (INIS)

Wan, J.-S.; Chen, L.-X.; Zhao, Z.-M.; Pan, X.-B.; Jing, C.-Y.; Zhao, X.-Q.; Liu, F.-H.

2003-01-01

Basing on our research of energy deposition in RPL (Reactor Pumped Laser) pumping cell and the laser power efficiency, a RPL test device on Pulsed Reactor has been designed. In addition, the laser beam power of the RPL test device is estimated in the paper. (author)

Miniature Scroll Pumps Fabricated by LIGA

Science.gov (United States)

Wiberg, Dean; Shcheglov, Kirill; White, Victor; Bae, Sam

2009-01-01

Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.

Wind power integration using individual heat pumps – Analysis of different heat storage options

DEFF Research Database (Denmark)

Hedegaard, Karsten; Mathiesen, Brian Vad; Lund, Henrik

2012-01-01

Significant installations of individual heat pumps are expected in future energy systems due to their economic competitiveness. This case study of the Danish energy system in 2020 with 50% wind power shows that individual heat pumps and heat storages can contribute to the integration of wind power....... Heat accumulation tanks and passive heat storage in the construction are investigated as two alternative storage options in terms of their ability to increase wind power utilisation and to provide cost-effective fuel savings. Results show that passive heat storage can enable equivalent to larger...... reductions in excess electricity production and fuel consumption than heat accumulation tanks. Moreover, passive heat storage is found to be significantly more cost-effective than heat accumulation tanks. In terms of reducing fuel consumption of the energy system, the installation of heat pumps is the most...

Liquid metal pump for nuclear reactors

International Nuclear Information System (INIS)

Allen, H.G.; Maloney, J.R.

1975-01-01

A pump for use in pumping high temperature liquids at high pressures, particularly liquid metals used to cool nuclear reactors is described. It is of the type in which the rotor is submerged in a sump but is fed by an inlet duct which bypasses the sump. A chamber, kept full of fluid, surrounds the pump casing into which fluid is bled from the pump discharge and from which fluid is fed to the rotor bearings and hence to the sump. This equalizes pressure inside and outside the pump casing and reduces or eliminates the thermal shock to the bearings and sump tank

Counter-rotating type axial flow pump unit in turbine mode for micro grid system

International Nuclear Information System (INIS)

Kasahara, R; Takano, G; Komaki, K; Murakami, T; Kanemoto, T

2012-01-01

Traditional type pumped storage system contributes to adjust the electric power unbalance between day and night, in general. This serial research proposes the hybrid power system combined the wind power unit with the pump-turbine unit, to provide the constant output for the grid system, even at the suddenly fluctuating/turbulent wind. In the pumping mode, the pump should operate unsteadily at not only the normal but also the partial discharge. The operation may be unstable in the rising portion of the head characteristics at the lower discharge, and/or bring the cavitation at the low suction head. To simultaneously overcome both weak points, the authors have proposed a superior pump unit that is composed of counter-rotating type impellers and a peculiar motor with double rotational armatures. This paper discusses the operation at the turbine mode of the above unit. It is concluded with the numerical simulations that this type unit can be also operated acceptably at the turbine mode, because the unit works so as to coincide the angular momentum change through the front runners/impellers with that thorough the rear runners/impellers, namely to take the axial flow at not only the inlet but also the outlet without the guide vanes.

On the Profitability of Variable Speed Pump-Storage-Power in Frequency Restoration Reserve

Science.gov (United States)

Filipe, Jorge; Bessa, Ricardo; Moreira, Carlos; Silva, Bernardo

2017-04-01

The increase penetration of renewable energy sources (RES) into the European power system has introduced a significant amount of variability and uncertainty in the generation profiles raising the needs for ancillary services as well as other tools like demand response, improved generation forecasting techniques and changes to the market design. While RES is able to replace energy produced by the traditional centralized generation, it cannot displace its capacity in terms of ancillary services provided. Therefore, centralized generation capacity must be retained to perform this function leading to over-capacity issues and underutilisation of the assets. Large-scale reversible hydro power plants represent the majority of the storage solution installed in the power system. This technology comes with high investments costs, hence the constant search for methods to increase and diversify the sources of revenue. Traditional fixed speed pump storage units typically operate in the day-ahead market to perform price arbitrage and, in some specific cases, provide downward replacement reserve (RR). Variable speed pump storage can not only participate in RR but also contribute to FRR, given their ability to control its operating point in pumping mode. This work does an extended analysis of a complete bidding strategy for Pumped Storage Power, enhancing the economic advantages of variable speed pump units in comparison with fixed ones.

Transformation of vibration signals in rotary blood pumps: the diagnostic potential of pump failure.

Science.gov (United States)

Kawahito, Koji

2013-09-01

Although non-destructive and continuous monitoring is indispensable for long-term circulatory support with rotary blood pumps, a practical monitoring system has not yet been developed. The objective of this study was to investigate the possibility of detecting pump failure caused by thrombus formation through the monitoring of vibration signals. The data acquisition equipment included vibration pickups, a charge amplifier, vibration analysis systems, and exclusive hardware. A pivot-bearing centrifugal pump with a mock circuit was investigated for vibration analysis. To simulate the four common areas of thrombus formation, we used a piece of silicon attached to each of the following four locations: the total area of the bottom of the impeller, an eccentric shape on the bottom of the impeller, a circular shape around the shaft top, and an eccentric shape on the top of the impeller. Vibration signals were picked up, and the power spectrum density analysis was performed at pump rotational speeds of 2100, 2400, and 3000 rpm. In this study, pump failure could be detected, and the types of imitation thrombi could be determined. We conclude that vibration detection with a computerized analysis system is a potentially valuable diagnostic tool for long-term circulatory support with rotary blood pumps.

High power diode pumped solid state lasers

International Nuclear Information System (INIS)

Solarz, R.; Albrecht, G.; Beach, R.; Comaskey, B.

1992-01-01

Although operational for over twenty years, diode pumped solid state lasers have, for most of their existence, been limited to individual diodes pumping a tiny volume of active medium in an end pumped configuration. More recent years have witnessed the appearance of diode bars, packing around 100 diodes in a 1 cm bar which have enabled end and side pumped small solid state lasers at the few Watt level of output. This paper describes the subsequent development of how proper cooling and stacking of bars enables the fabrication of multi kill average power diode pump arrays with irradiances of 1 kw/cm peak and 250 W/cm 2 average pump power. Since typical conversion efficiencies from the diode light to the pumped laser output light are of order 30% or more, kW average power diode pumped solid state lasers now are possible

Seawater pumping as an electricity storage solution for photovoltaic energy systems

International Nuclear Information System (INIS)

Manfrida, Giampaolo; Secchi, Riccardo

2014-01-01

The stochastic nature of several renewable energy sources has raised the problem of designing and building storage facilities, which can help the electricity grid to sustain larger and larger contribution of renewable energy. Seawater pumped electricity storage is proposed as a good option for PV (Photovoltaic) or solar thermal power plants, located in suitable places close to the coast line. Solar radiation has a natural daily cycle, and storage reservoirs of limited capacity can substantially reduce the load to the electricity grid. Different modes of pump operation (fixed or variable speed) are considered, the preliminary sizing of the PV field and seawater reservoir is performed, and the results are comparatively assessed over a year-long simulated operation. The results show that PV pumped storage, even if not profitable in the present situation of the renewable energy Italian electricity market, is effective in decreasing the load on the transmission grid, and would possibly be attractive in the future, also in the light of developing off-grid applications. - Highlights: • A grid-connected seawater pumping system using photovoltaic power is proposed and its performance analyzed. • Year-round simulations are run with different sizes of photovoltaic field and reservoir. • An analysis is run about the profitability of the storage system, examining performance indexes and the cost of plant. • The system proposed appears near to attract the interest of the market

Ekman pumping mechanism driving precipitation anomalies in response to equatorial heating

Science.gov (United States)

Hamouda, Mostafa E.; Kucharski, Fred

2018-03-01

In this paper some basic mechanisms for rainfall teleconnections to a localized tropical sea surface temperature anomaly are re-visited using idealized AGCM aqua-planet simulations. The dynamical response is generally in good agreement with the Gill-Matsuno theory. The mechanisms analyzed are (1) the stabilization of the tropical troposphere outside the heating region, (2) the Walker circulation modification and (3) Ekman pumping induced by the low-level circulation responses. It is demonstrated that all three mechanisms, and in particular (2) and (3), contribute to the remote rainfall teleconnections. However, mechanism (3) best coincides with the overall horizontal structure of rainfall responses. It is shown by using the models boundary layer parameterization that low-level vertical velocities are indeed caused by Ekman pumping and that this induces vertical velocities in the whole tropospheric column through convective feedbacks. Also the modification of the responses due to the presence of idealized warm pools is investigated. It is shown that warm pools modify the speed of the tropical waves, consistent with Doppler shifts and are thus able to modify the Walker circulation adjustments and remote rainfall responses. The sensitivity of the responses, and in particular the importance of the Ekman pumping mechanism, to large variations in the drag coefficient is also tested, and it is shown that the Ekman pumping mechanism is robust for a wide range of values.

Simulations of longitudinally pumped dye laser amplifier

International Nuclear Information System (INIS)

Takehisa, Kiwamu; Takemori, Satoshi

1995-01-01

Simulations of a copper laser pumped dye laser amplifier and new designs of the longitudinally pumped dye laser amplifier are presented. The simulations take the consideration of the amplified spontaneous emission (ASE). The new designs utilize a center-hole reflector instead of a dichroic mirror. The simulation results indicate that the poor spatial overlap between the pump beam and the dye beam in the transverse pumping not only reduces the laser output power, but also generates ASE strongly. The results also indicate that the longitudinal pumping is as efficient as the transverse pumping. (author)

Advanced heat pumps and their economic aspects. The case for super heat pump

International Nuclear Information System (INIS)

Yabe, Akira; Akiya, Takaji

1996-01-01

The results of the economic evaluation of the Super Heat Pump Energy Accumulation System project in Japan are reviewed. It is reported that although the initial costs of super heat pumps are higher than those of conventional systems, the calculated operating costs of a unit thermal energy produced by a super heat pump is reduced considerably. All the various system concepts with thermal/chemical storage were evaluated economically with the exception of the high temperature thermal storage systems using salt ammonia complexes and solvation. These latter systems were not further developed as pilot plants. It is advocated to accelerate the introduction of super heat pumps by facilitating their market introduction. Actual clathrate chemical storage systems have shown that the annual costs are comparable to those of an ice storage system. Clathrate systems will find their way in the market. It is concluded that most of the super heat pump systems and clathrate storage systems will be economic in the future. A big challenge however still exists in further improving the cost effectiveness of heat storage in tanks by reducing their size dramatically (to 1/10th)

Advances in heat pump systems: A review

International Nuclear Information System (INIS)

Chua, K.J.; Chou, S.K.; Yang, W.M.

2010-01-01

Heat pump systems offer economical alternatives of recovering heat from different sources for use in various industrial, commercial and residential applications. As the cost of energy continues to rise, it becomes imperative to save energy and improve overall energy efficiency. In this light, the heat pump becomes a key component in an energy recovery system with great potential for energy saving. Improving heat pump performance, reliability, and its environmental impact has been an ongoing concern. Recent progresses in heat pump systems have centred upon advanced cycle designs for both heat- and work-actuated systems, improved cycle components (including choice of working fluid), and exploiting utilisation in a wider range of applications. For the heat pump to be an economical proposition, continuous efforts need to be devoted to improving its performance and reliability while discovering novel applications. Some recent research efforts have markedly improved the energy efficiency of heat pump. For example, the incorporation of a heat-driven ejector to the heat pump has improved system efficiency by more than 20%. Additionally, the development of better compressor technology has the potential to reduce energy consumption of heat pump systems by as much as 80%. The evolution of new hybrid systems has also enabled the heat pump to perform efficiently with wider applications. For example, incorporating a desiccant to a heat pump cycle allowed better humidity and temperature controls with achievable COP as high as 6. This review paper provides an update on recent developments in heat pump systems, and is intended to be a 'one-stop' archive of known practical heat pump solutions. The paper, broadly divided into three main sections, begins with a review of the various methods of enhancing the performance of heat pumps. This is followed by a review of the major hybrid heat pump systems suitable for application with various heat sources. Lastly, the paper presents novel

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

Tendency of nuclear pumps for PWR primary system

International Nuclear Information System (INIS)

Shibata, Takeshi

1976-01-01

At present, large PWR power stations of more than 1,000 MW are successively constructed, and the pumps used there have become large. The progress and tendency of the technical development of main pumps in primary system are described. The increase of the capacity of power stations is accomplished by increasing the circulating coolant quantity per loop or the number of loops. Same standard primary coolant pumps are employed in the plants from 500 to 1,100 MW. The type of primary coolant pumps changed from canned type to shaft seal type, and the advantages of the shaft seal type are cheap production cost, high efficiency, and the easy utilization of inertia force. The bearings and shaft seals are thermally insulated from primary coolant. As for auxiliary pumps, reciprocating filling-up pumps and centrifugal high pressure injection pumps are used for 500 MW plants, but only centrifugal pumps are used for both purposes in 800 MW plants, and in 1,100 MW plants, the pumps of both types for separate purposes and centrifugal pumps for combined purposes are installed. Horizontal or vertical pumps of same type are used as containment vessel-spraying pumps and excess heat-eliminating pumps. The type of boric acid pumps changed from canned type to mechanical seal type. (Kako, I.)

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.

Mono pump equipment evaluation report

International Nuclear Information System (INIS)

1992-01-01

A mobile pump has been designed, developed, and tested as part of an effort to increase oil spill response time, improve oil/water recovery efficiency and reduce cleanup and reclamation costs. The pump is mounted on an engine powered track carrier, and can be detached from the carrier and skidded into remote spill sites or transported by helicopter. The pump can safely recover highly volatile flammable substances such as condensate and gasoline, as well as heavy crude oil up to 5000 centipoise viscosity. It can pump up to 30 gal/min at zero head, and up to 1000 feet in a vertical direction. 13 figs

Wind power integration with heat pumps, heat storages, and electric vehicles - Energy systems analysis and modelling

Energy Technology Data Exchange (ETDEWEB)

Hedegaard, K.

2013-09-15

Denmark by about 300-600 MW, corresponding to the size of a large power plant. This can be achieved when investing in socio-economically feasible heat storages complementing the heat pumps. The potential for reducing the required investments in peak/reserve capacities is crucial for the feasibility of the heat storages. Intelligent heat storage in the building structure is identified as socio-economically feasible in 20-75 % of the houses with heat pump installations, depending on the cost of control equipment in particular. Investment in control equipment, enabling utilisation of existing hot water tanks for flexible heat pump operation, is found socio-economically feasible in about 20-70 % of the houses. In contrast, heat accumulation tanks are not competitive, due to their higher investments costs. Further analyses investigate the system effects of a gradual large-scale implementation of battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs) in Denmark, Finland, Norway, Sweden, and Germany towards 2030. When charged/discharged intelligently, the electric vehicles can, in the long term, facilitate larger wind power investments, while they in the short term in many cases are likely to result in increased coal-based electricity generation. The electric vehicles can contribute significantly to reducing CO{sub 2} emissions, while system costs are generally increased, due to assumed investments in the costly BEVs. The need for peak/reserve capacities can be reduced through the use of vehicle-to-grid capability. Competing flexibility measures, such as large heat pumps, electric boilers, and thermal storages in the district heating system, have also been included in the energy systems analyses. These technologies can together facilitate increased wind power investments and reduce CO{sub 2} emissions in the same order of magnitude as a large-scale implementation of electric vehicles. Overall, it is concluded that individual heat pumps, flexibility

Hydrostatic radial bearing of centrifugal pump

International Nuclear Information System (INIS)

Skalicky, A.

1976-01-01

A hydrostatic radial pump is described characterized by the fact that part of the medium off-taken from delivery is used as a lubricating medium. Two additional bodies are placed alongside a hydrostatic bearing with coils in between them and the pump shaft; the coils have an opposite pitch. The feed channel for the hydrostatic bearing pocket is linked to delivery. The coil outlets are connected to the pump suction unit. Two rotating coils placed alongside the hydrostatic bearing will considerably simplify the communication channel design and reduce the dependence on the pump shaft deflections. The addition of another rotating coil in the close vicinity of the pump shaft or directly on the shaft further increases the efficiency. The bearing can be used in designing vertical circulating pumps for the cooling circuits of nuclear reactors. (J.B.)

Geothermal heat pumps - Trends and comparisons

Energy Technology Data Exchange (ETDEWEB)

Lund, John W

1989-01-01

Heat pumps are used where geothermal water or ground temperatures are only slightly above normal, generally 50 to 90 deg. F. Conventional geothermal heating (and cooling) systems are not economically efficient at these temperatures. Heat pumps, at these temperatures, can provide space heating and cooling, and with a desuperheater, domestic hot water. Two basic heat pump systems are available, air-source and water- or ground-source. Water- and ground-coupled heat pumps, referred to as geothermal heat pumps (GHP), have several advantages over air-source heat pumps. These are: (1) they consume about 33% less annual energy, (2) they tap the earth or groundwater, a more stable energy source than air, (3) they do not require supplemental heat during extreme high or low outside temperatures, (4) they use less refrigerant (freon), and (5) they have a simpler design and consequently less maintenance.

Evaluation of personal air sampling pumps

International Nuclear Information System (INIS)

Ritter, P.D.; Novick, V.J.; Alvarez, J.L.; Huntsman, B.L.

1987-01-01

Personal air samplers are used to more conveniently obtain breathing zone samples from individuals over periods of several hours. Personal air sampling pumps must meet minimum performance levels under all working conditions to be suitable for use in radiation protection programs. In addition, the pumps should be simple to operate and as comfortable to wear as possible. Ten models of personal air sampling pumps were tested to evaluate their mechanical performance and physical characteristics. The pumps varied over a wide range in basic performance and operating features. Some of the pumps were found to have adequate performance for use in health physics air sampling applications. 3 references, 2 figures, 5 tables

Centrifugal pumps and allied machinery

CERN Document Server

Anderson, HH

1994-01-01

This book will be of vital interest to all engineers and designers concerned with centrifugal pumps and turbines. Including statistical information derived from 20000 pumps and 700 turbines with capacities of 5gpm to 5000000gpm, this book offers the widest range and scope of information currently available. Statistical analyses suggest practical methods of increasing pump performance and provide valuable data for new design aspects.

Thermodynamic analysis of pumped thermal electricity storage

International Nuclear Information System (INIS)

White, Alexander; Parks, Geoff; Markides, Christos N.

2013-01-01

The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater need for electricity storage. Although there are many existing and emerging storage technologies, most have limitations in terms of geographical constraints, high capital cost or low cycle life, and few are of sufficient scale (in terms of both power and storage capacity) for integration at the transmission and distribution levels. This paper is concerned with a relatively new concept which will be referred to here as Pumped Thermal Electricity Storage (PTES), and which may be able to make a significant contribution towards future storage needs. During charge, PTES makes use of a high temperature ratio heat pump to convert electrical energy into thermal energy which is stored as ‘sensible heat’ in two thermal reservoirs, one hot and one cold. When required, the thermal energy is then converted back to electricity by effectively running the heat pump backwards as a heat engine. The paper focuses on thermodynamic aspects of PTES, including energy and power density, and the various sources of irreversibility and their impact on round-trip efficiency. It is shown that, for given compression and expansion efficiencies, the cycle performance is controlled chiefly by the ratio between the highest and lowest temperatures in each reservoir rather than by the cycle pressure ratio. The sensitivity of round-trip efficiency to various loss parameters has been analysed and indicates particular susceptibility to compression and expansion irreversibility

Graphical user interface simplifies infusion pump programming and enhances the ability to detect pump-related faults.

Science.gov (United States)

Syroid, Noah; Liu, David; Albert, Robert; Agutter, James; Egan, Talmage D; Pace, Nathan L; Johnson, Ken B; Dowdle, Michael R; Pulsipher, Daniel; Westenskow, Dwayne R

2012-11-01

Drug administration errors are frequent and are often associated with the misuse of IV infusion pumps. One source of these errors may be the infusion pump's user interface. We used failure modes-and-effects analyses to identify programming errors and to guide the design of a new syringe pump user interface. We designed the new user interface to clearly show the pump's operating state simultaneously in more than 1 monitoring location. We evaluated anesthesia residents in laboratory and simulated environments on programming accuracy and error detection between the new user interface and the user interface of a commercially available infusion pump. With the new user interface, we observed the number of programming errors reduced by 81%, the number of keystrokes per task reduced from 9.2 ± 5.0 to 7.5 ± 5.5 (mean ± SD), the time required per task reduced from 18.1 ± 14.1 seconds to 10.9 ± 9.5 seconds and significantly less perceived workload. Residents detected 38 of 70 (54%) of the events with the new user interface and 37 of 70 (53%) with the existing user interface, despite no experience with the new user interface and extensive experience with the existing interface. The number of programming errors and workload were reduced partly because it took less time and fewer keystrokes to program the pump when using the new user interface. Despite minimal training, residents quickly identified preexisting infusion pump problems with the new user interface. Intuitive and easy-to-program infusion pump interfaces may reduce drug administration errors and infusion pump-related adverse events.

METHOD FOR OPTIMIZING THE ENERGY OF PUMPS

NARCIS (Netherlands)

Skovmose Kallesøe, Carsten; De Persis, Claudio

2013-01-01

The device for energy-optimization on operation of several centrifugal pumps controlled in rotational speed, in a hydraulic installation, begins firstly with determining which pumps as pilot pumps are assigned directly to a consumer and which pumps are hydraulically connected in series upstream of

Electrostatic coupling of ion pumps.

Science.gov (United States)

Nieto-Frausto, J; Lüger, P; Apell, H J

1992-01-01

In this paper the electrostatic interactions between membrane-embedded ion-pumps and their consequences for the kinetics of pump-mediated transport processes have been examined. We show that the time course of an intrinsically monomolecular transport reaction can become distinctly nonexponential, if the reaction is associated with charge translocation and takes place in an aggregate of pump molecules. First we consider the electrostatic coupling of a single dimer of ion-pumps embedded in the membrane. Then we apply the treatment to the kinetic analysis of light-driven proton transport by bacteriorhodopsin which forms two-dimensional hexagonal lattices. Finally, for the case of nonordered molecules, we also consider a model in which the pumps are randomly distributed over the nodes of a lattice. Here the average distance is equal to that deduced experimentally and the elemental size of the lattice is the effective diameter of one single pump. This latter model is applied to an aggregate of membrane-embedded Na, K- and Ca-pumps. In all these cases the electrostatic potential considered is the exact solution calculated from the method of electrical images for a plane membrane of finite thickness immersed in an infinite aqueous solution environment. The distributions of charges (ions or charged binding sites) are considered homogeneous or discrete in the membrane and/or in the external solution. In the case of discrete distributions we compare the results from a mean field approximation and a stochastic simulation.

Peripheral tissue metabolism during off-pump versus on-pump coronary artery bypass graft surgery: the microdialysis study.

Science.gov (United States)

Pojar, Marek; Mand'ák, Jirí; Cibícek, Norbert; Lonský, Vladimír; Dominik, Jan; Palicka, Vladimír; Kubícek, Jaroslav

2008-05-01

The aim of this study was to monitor and compare metabolic changes in the skeletal muscle during coronary artery bypass grafting surgery with and without cardiopulmonary bypass (CPB) by means of interstitial microdialysis. Glucose, lactate, pyruvate and glycerol were assessed as markers of basic metabolism and tissue perfusion. Twenty patients undergoing surgical myocardial revascularization were enrolled in this pilot study. Ten patients were operated on without CPB (group A, off-pump) and 10 patients using normothermic CPB (group B, on-pump). Interstitial microdialysis was performed by a CMA 60 (CMA/Microdialysis AB, Sweden) probe, inserted into the patient's left deltoid muscle. Microdialysis measurements were performed at 30 min intervals. Glucose, lactate, pyruvate and glycerol were measured in samples using a CMA 600 Analyser (CMA/Microdialysis AB, Sweden). Results in both groups were statistically processed and the groups were compared. Both groups were similar with regards to preoperative characteristics. Dynamic changes of interstitial concentrations of the measured analytes were found in off-pump (group A) and on-pump (group B) patients during the operation. There were no significant differences in dialysate concentrations of glucose and lactate between the groups. Significant differences were detected in pyruvate concentrations, lactate-pyruvate ratio and glycerol concentrations between off-pump versus on-pump patients. Pyruvate concentrations were higher in the off-pump group (plactate-pyruvate ratios indicating the aerobic/anaerobic metabolism status were lower in the off-pump group (pglucose, glycerol, pyruvate and lactate were found in both groups of patients (off-pump and on-pump). The presented preliminary results suggest that extracorporeal circulation during cardiac operations could compromise skeletal muscle energy metabolism.

Fluidic pumps

International Nuclear Information System (INIS)

Priestman, G.H.

1990-01-01

A fluidic pump has primary and secondary vessels connected by a pipe, a displacement vessel having liquid to be delivered through a pipe via a rectifier provided with a feed tank. A drive unit delivers pressure fluid to a line to raise liquid and compress trapped gas or liquid in the space, including the pipe between the liquids in the two vessels and thus drive liquid out of the displacement vessel. The driving gas is therefore separated by the barrier liquid and the trapped gas or liquid from the liquid to be pumped which liquid could be e.g. radioactive. (author)

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.)

Development of ceramic vacuum pumps for fusion reactors

International Nuclear Information System (INIS)

Anon.

1990-01-01

To achieve the magnetic field resistance and tritium resistance which are required for vacuum pumps for fusion reactors, a vacuum pump consisting of middle-ceramic turbo molecular pump (TMP), using ceramic rotor and ceramic turbo roughing pump was developed. In colaboration with the Japan Atomic Energy Research Institute, performance tests on pumping speed, compression ratio of middle-ceramic TMP and both of pumping characteristics were carried out. Sufficient performances were obtained. It was showed that middle-ceramic TMP had pumping speed of more than 500 l/s, and could achieve the pressure below 4 x 10 -7 Pa. Ceramic turbo roughing pump could vacuum from atmospheric pressure. It is concluded that complete oil-free ceramic vacuum pump can be put into practical use (K.S.)

Microelectromechanical pump utilizing porous silicon

Science.gov (United States)

Lantz, Jeffrey W [Albuquerque, NM; Stalford, Harold L [Norman, OK

2011-07-19

A microelectromechanical (MEM) pump is disclosed which includes a porous silicon region sandwiched between an inlet chamber and an outlet chamber. The porous silicon region is formed in a silicon substrate and contains a number of pores extending between the inlet and outlet chambers, with each pore having a cross-section dimension about equal to or smaller than a mean free path of a gas being pumped. A thermal gradient is provided along the length of each pore by a heat source which can be an electrical resistance heater or an integrated circuit (IC). A channel can be formed through the silicon substrate so that inlet and outlet ports can be formed on the same side of the substrate, or so that multiple MEM pumps can be connected in series to form a multi-stage MEM pump. The MEM pump has applications for use in gas-phase MEM chemical analysis systems, and can also be used for passive cooling of ICs.

Parallel operation of primary sodium pumps in FBTR

International Nuclear Information System (INIS)

Athmalingam, S.; Ellappan, T.R.; Vaidyanathan, G.; Chetal, S.C.; Bhoje, S.B.

1994-01-01

Sodium pumps used in the primary main circuit of Fast Breeder Test Reactor (FBTR) are centrifugal pumps. These pumps have a free level of sodium with a cover gas above it to simplify the pump seal arrangement. The sodium level in the pumps will vary based on the flow. The minimum level is governed by consideration of gas entrainment and net positive suction head (NPSH) to the pump while the maximum level is limited by sodium entering the pump tank gas line. There is a special feature in these pumps in that a small portion of the pump outlet sodium flow is led back into the suction chamber to maintain level and avoid gas entrainment. A control valve in this line helps in controlling the level at the desired value. With parallel operation of two sodium pumps a study was conducted to find the regions of safe operation of the two pumps. The purpose of this paper is to give the various design features and methodology of the analysis to arrive at the limiting condition of operation for the different operating states of the two pumps and the effect of pump speed variations on the fluctuations in sodium flows. (author). 6 figs

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.

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.

Magnetic heat pump flow director

Science.gov (United States)

Howard, Frank S. (Inventor)

1995-01-01

A fluid flow director is disclosed. The director comprises a handle body and combed-teeth extending from one side of the body. The body can be formed of a clear plastic such as acrylic. The director can be used with heat exchangers such as a magnetic heat pump and can minimize the undesired mixing of fluid flows. The types of heat exchangers can encompass both heat pumps and refrigerators. The director can adjust the fluid flow of liquid or gas along desired flow directions. A method of applying the flow director within a magnetic heat pump application is also disclosed where the comb-teeth portions of the director are inserted into the fluid flow paths of the heat pump.

Features of rotary pump diagnostics without dismantling

Directory of Open Access Journals (Sweden)

Sergeev K. О.

2017-12-01

Full Text Available In ship power plants, rotor pumps have become very popular providing the transfer of various viscous fluids: fuels, oils, etc. Like all ship's mechanisms, pumps need proper maintenance and monitoring of technical condition. The most expedient is maintenance and repair carried out according to the results of dismantling diagnosis. The methods of vibrodiagnostics are mostly widespread for the diagnosis of pumps. Vibrodiagnosis of rotary pumps has a number of features due to the nature and condition of pumped fluids. The norms of the Russian Maritime Register of Shipping are used for setting standards of vibration and diagnostics of the rotary pumps' technical condition. To clarify the features of vibration diagnostics of rotary pumps some measurements have been made on a special bench that simulates various modes of ship's pumps' operation: different pressure in the system and temperature of the pumped medium. As a result of measurements one-third octave and narrow-band vibration spectra of pumps have been obtained at various developed pressures and temperatures of the pumped fluid. The performed analysis has shown that the RMRS norms for diagnostics of ship rotary pumps have insufficient informative value inasmuch they do not take into account the dependence of the vibrational signal spectrum on the developed pressure and temperature of the pumped fluid. The nature of the received signals shows that the levels of a third-octave spectrum of the vibration velocity depend significantly on the temperature of the pumped fluids, this fact must be taken into account when applying the RMRS norms. The fluid temperature has a great influence on the nature of the narrow-band vibration acceleration spectrum in the area of medium frequencies, less influence – on the nature of the vibration velocity spectrum. The conclusions have been drawn about the advisability of using the narrow-band vibration spectra and the envelope spectra of the high

Role of pump hydro in electric power systems

Science.gov (United States)

Bessa, R.; Moreira, C.; Silva, B.; Filipe, J.; Fulgêncio, N.

2017-04-01

This paper provides an overview of the expected role that variable speed hydro power plants can have in future electric power systems characterized by a massive integration of highly variable sources. Therefore, it is discussed the development of a methodology for optimising the operation of hydropower plants under increasing contribution from new renewable energy sources, addressing the participation of a hydropower plant with variable speed pumping in reserve markets. Complementarily, it is also discussed the active role variable speed generators can have in the provision of advanced frequency regulation services.

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)

Factors governing sustainable groundwater pumping near a river

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y.; Hubbard, S.S.; Finsterle, S.

2011-01-15

The objective of this paper is to provide new insights into processes affecting riverbank filtration (RBF). We consider a system with an inflatable dam installed for enhancing water production from downstream collector wells. Using a numerical model, we investigate the impact of groundwater pumping and dam operation on the hydrodynamics in the aquifer and water production. We focus our study on two processes that potentially limit water production of an RBF system: the development of an unsaturated zone and riverbed clogging. We quantify river clogging by calibrating a time-dependent riverbed permeability function based on knowledge of pumping rate, river stage, and temperature. The dynamics of the estimated riverbed permeability reflects clogging and scouring mechanisms. Our results indicate that (1) riverbed permeability is the dominant factor affecting infiltration needed for sustainable RBF production; (2) dam operation can influence pumping efficiency and prevent the development of an unsaturated zone beneath the riverbed only under conditions of sufficient riverbed permeability; (3) slow river velocity, caused by dam raising during summer months, may lead to sedimentation and deposition of fine-grained material within the riverbed, which may clog the riverbed, limiting recharge to the collector wells and contributing to the development of an unsaturated zone beneath the riverbed; and (4) higher river flow velocities, caused by dam lowering during winter storms, scour the riverbed an thus increase its permeability. These insights can be used as the basis for developing sustainable water management of a RBF system.

Method for optimising the energy of pumps

NARCIS (Netherlands)

Skovmose Kallesøe, Carsten; De Persis, Claudio

2011-01-01

The method involves determining whether pumps (pu1, pu5) are directly assigned to loads (v1, v3) as pilot pumps (pu2, pu3) and hydraulically connected upstream of the pilot pumps. The upstream pumps are controlled with variable speed for energy optimization. Energy optimization circuits are selected

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.

Particle exhaust scheme using an in-vessel cryocondensation pump in the advanced divertor configuration of the DIII-D tokamak

International Nuclear Information System (INIS)

Menon, M.M.; Mioduszewski, P.K.; Owen, L.W.; Anderson, P.M.; Baxi, C.B.; Langhorn, A.; Luxon, J.L.; Mahdavi, M.A.; Schaffer, M.J.; Schaubel, K.M.; "" class="author-name" title=" (General Atomics Co., San Diego, CA (United States))" data-affiliation=" (General Atomics Co., San Diego, CA (United States))" >Smith, J.P>

1992-01-01

In this paper, a particle exhaust scheme using a cryocondensation pump in the advanced divertor configuration of the DIII-D tokamak is described. In this configuration, the pump is located inside a baffle chamber within the tokamak, designed to receive particles reflected off the divertor strike region. A concentric coaxial loop with forced-convection flow of two-phase helium is selected as the cryocondensation surface. The pumping configuration is optimized by Monte Carlo techniques to provide maximum exhaust efficiency while minimizing the deleterious effects of impingement of energetic plasma particles on cryogenic surfaces. Heat loading contributions from various sources on the cryogenic surfaces are estimated, based on which the cryogenic surfaces are estimated, based on which the cryogenic flow loop for the pump is designed. The mechanical aspects of the pump, designed to meet the many challenging requirements of operating the cryopump internal to the tokamak vacuum and in close proximity with the high-temperature plasma, are also outlined

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.

Efflux pump induction by quaternary ammonium compounds and fluoroquinolone resistance in bacteria.

Science.gov (United States)

Buffet-Bataillon, Sylvie; Tattevin, Pierre; Maillard, Jean-Yves; Bonnaure-Mallet, Martine; Jolivet-Gougeon, Anne

2016-01-01

Biocides, primarily those containing quaternary ammonium compounds (QAC), are heavily used in hospital environments and various industries (e.g., food, water, cosmetic). To date, little attention has been paid to potential implications of QAC use in the emergence of antibiotic resistance, especially fluoroquinolone-resistant bacteria in patients and in the environment. QAC-induced overexpression of efflux pumps can lead to: cross resistance with fluoroquinolones mediated by multidrug efflux pumps; stress response facilitating mutation in the Quinolone Resistance Determining Region; and biofilm formation increasing the risk of transfer of mobile genetic elements carrying fluoroquinolone or QAC resistance determinants. By following the European Biocidal Product Regulation, manufacturers of QAC are required to ensure that their QAC-based biocidal products are safe and will not contribute to emerging bacterial resistance.

XFEL resonant photo-pumping of dense plasmas and dynamic evolution of autoionizing core hole states

Science.gov (United States)

Rosmej, F. B.; Moinard, A.; Renner, O.; Galtier, E.; Lee, J. J.; Nagler, B.; Heimann, P. A.; Schlotter, W.; Turner, J. J.; Lee, R. W.; Makita, M.; Riley, D.; Seely, J.

2016-03-01

Similarly to the case of LIF (Laser-Induced Fluorescence), an equally revolutionary impact to science is expected from resonant X-ray photo-pumping. It will particularly contribute to a progress in high energy density science: pumped core hole states create X-ray transitions that can escape dense matter on a 10 fs-time scale without essential photoabsorption, thus providing a unique possibility to study matter under extreme conditions. In the first proof of principle experiment at the X-ray Free Electron Laser LCLS at SCLAC [Seely, J., Rosmej, F.B., Shepherd, R., Riley, D., Lee, R.W. Proposal to Perform the 1st High Energy Density Plasma Spectroscopic Pump/Probe Experiment”, approved LCLS proposal L332 (2010)] we have successfully pumped inner-shell X-ray transitions in dense plasmas. The plasma was generated with a YAG laser irradiating solid Al and Mg targets attached to a rotating cylinder. In parallel to the optical laser beam, the XFEL was focused into the plasma plume at different delay times and pump energies. Pumped X-ray transitions have been observed with a spherically bent crystal spectrometer coupled to a Princeton CCD. By using this experimental configuration, we have simultaneously achieved extremely high spectral (λ/δλ ≈ 5000) and spatial resolution (δx≈70 μm) while maintaining high luminosity and a large spectral range covered (6.90 - 8.35 Å). By precisely measuring the variations in spectra emitted from plasma under action of XFEL radiation, we have successfully demonstrated transient X- ray pumping in a dense plasma.

Recent start of two field measurements of new heat pumps; Zwei Feldmessungen neuer Waermepumpen gestartet

Energy Technology Data Exchange (ETDEWEB)

Buehring, A.; Miara, M.; Russ, C.; Bichler, C.; Becker, R. [Fraunhofer-Inst. fuer Solare Energiesysteme ISE, Freiburg (Germany)

2006-07-01

The contribution presents two new large-scale field measurements of heat pumps that were started in 2006. In both projects, measurements are made on a large number of heat pumps in real operation. Volume flows, temperatures, heat volumes and power consumption are measured with high temporal resolution. The data are stored and evaluated daily by Fraunhofer ISE via remote data transfer. From the measurements, characteristic values, system behaviour, quality characteristics and correlations with plant design data will be derived. In the project ''Waermepumpen-Effizienz'', 140 heat pumps of 7 producers will be tested. About half of them started operation in 2006 while the other half will be commissioned in 2008. The focus is on low capacities of 5-10 kW thermal power and with ambient air and soil as heat sources. Efficiencies will be tested in different conditions and with different system concepts, and development concepts will be derived for smaller heat pumps for low-energy buildings. These will close the current gap between available heat pumps and compact ventilation units with off-air heat pumps for passive buildings. The project is funded by the Federal Minister of Economy and TEchnology, by the seven producers and by EnBW and E.ON. The second project, ''Ersatz von Oelheizkesseln im Wohngebaeudebestand durch Waermepumpen'', comprises measurements on 100 heat pumps of leading producers in real operations. All heat pumps are suited for use in older buildings. The measuring equipment and procedure are similar to the first-mentioned project. The economic efficiency and CO2 emissions of the heat pumps are compared with those of new oil-fuelled boilers as an alternative in the modernisation of older buildings. The measurements will also show what thermal insulation is required for maximum economic efficiency of the heat pumps. The results will be made public to customers, fitters, producers, planners, universities, politicians

Towards quantifying the response of the oceans’ biological pump to climate change

Directory of Open Access Journals (Sweden)

Philip Wallace Boyd

2015-10-01

Full Text Available The biological pump makes a major global contribution to the sequestration of carbon-rich particles in the oceans’ interior. This pump has many component parts from physics to ecology that together control its efficiency in exporting particles. Hence, the influence of climate change on the functioning and magnitude of the pump is likely to be complex and non-linear. Here, I employ a published 1-D coupled surface-subsurface Particulate Organic Carbon (POC export flux model to systematically explore the potential influence of changing oceanic conditions on each of the pump’s ‘moving parts’, in both surface and subsurface waters. These simulations were run for typical high (High Nutrient Low Chlorophyll, HNLC and low (Low Nutrient Low Chlorophyll, LNLC latitude sites. Next, I couple pump components that have common drivers, such as temperature, to investigate more complex scenarios involving concurrent climate-change mediated alteration of multiple ‘moving parts’ of the pump. Model simulations reveal that in the surface ocean, changes to algal community structure (i.e., a shift towards small cells has the greatest individual influence (decreased flux on downward POC flux in the coming decades. In subsurface waters, a shift in zooplankton community structure has the greatest single effect on POC flux (decreased in a future ocean. More complex treatments, in which up to ten individual factors (across both surface and subsurface processes were concurrently altered, ~ halved the POC flux at both high and low latitudes. In general climate-mediated changes to surface ocean processes had a greater effect on the magnitude of POC flux than alteration of subsurface processes, some of which negated one another. This relatively simple 1-D model provides initial insights into the most influential processes that may alter the future performance of this pump, and more importantly reveals many knowledge gaps that require urgent attention before we can

Pump limiter experiment in the TFR tokamak

International Nuclear Information System (INIS)

Anon.

1987-01-01

Pump limiter experiments are carried out in the TFR Tokamak. The first TFR pump limiter is located in the outer part of the torus, its double-throat head is made of graphite tiles, the neutralizer plates are made of stainless steel, and it is pumped by a 3500 l s -1 titanium sublimation pump. The first attempts showed that the exhaust efficiency ε of this pump limiter was low (1.5% of the total plasma particle efflux). To improve on these results, a new limiter head with a single longer throat has been built. The particles were better trapped and the pumping achieved an important decrease of the recycling coefficient. Geometric features and also the highly non linear regime of pressure in the pump limiter as a function of the density at the entrance slot could explain the increase by a factor 3.5 of the exhaust efficiency (ε = 5%). Ion temperatures of the order of a few eV have been deduced from Doppler broadening measurements at the neutralizer plate of the pump limiter. (orig.)

Orientational and electronic contributions to the third-order susceptibilities of cryogenic liquids

International Nuclear Information System (INIS)

Kildal, H.; Brueck, S.R.J.

1980-01-01

Alternating current Kerr effect and third-harmonic generation (THG) are reported for the cryogenic liquids CO, O 2 , N 2 , and Ar pumped by CO 2 TEA laser radiation. The THG experiments measure the hyperpolarizability, while the Kerr effect measurements probe the total nonresonant third-order susceptibility chi/sup( 3 ), arising from both molecular orientation and electronic hyperpolarizability. The THG process in liquid CO is dominated by a vibrational two-photon resonant contribution for the CO 2 R(6) pump line at 9.35 μm. By studying the interference between the resonant and nonresonant contributions in liquid CO--O 2 mixtures the hyperpolarizability of liquid O 2 has been determined relative to the two-photon resonant chi/sup( 3 ) of liquid CO. These measurements give the first experimental confirmation for liquid media that the two-photon resonance contribution to polarized scattering consists of both narrow and broad linewidth components associated with, respectively, the isotropic and anisotropic Raman polarizabilities

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

A Generic analytical solution for modelling pumping tests in wells intersecting fractures

Science.gov (United States)

Dewandel, Benoît; Lanini, Sandra; Lachassagne, Patrick; Maréchal, Jean-Christophe

2018-04-01

The behaviour of transient flow due to pumping in fractured rocks has been studied for at least the past 80 years. Analytical solutions were proposed for solving the issue of a well intersecting and pumping from one vertical, horizontal or inclined fracture in homogeneous aquifers, but their domain of application-even if covering various fracture geometries-was restricted to isotropic or anisotropic aquifers, whose potential boundaries had to be parallel or orthogonal to the fracture direction. The issue thus remains unsolved for many field cases. For example, a well intersecting and pumping a fracture in a multilayer or a dual-porosity aquifer, where intersected fractures are not necessarily parallel or orthogonal to aquifer boundaries, where several fractures with various orientations intersect the well, or the effect of pumping not only in fractures, but also in the aquifer through the screened interval of the well. Using a mathematical demonstration, we show that integrating the well-known Theis analytical solution (Theis, 1935) along the fracture axis is identical to the equally well-known analytical solution of Gringarten et al. (1974) for a uniform-flux fracture fully penetrating a homogeneous aquifer. This result implies that any existing line- or point-source solution can be used for implementing one or more discrete fractures that are intersected by the well. Several theoretical examples are presented and discussed: a single vertical fracture in a dual-porosity aquifer or in a multi-layer system (with a partially intersecting fracture); one and two inclined fractures in a leaky-aquifer system with pumping either only from the fracture(s), or also from the aquifer between fracture(s) in the screened interval of the well. For the cases with several pumping sources, analytical solutions of flowrate contribution from each individual source (fractures and well) are presented, and the drawdown behaviour according to the length of the pumped screened interval of

46 CFR 98.30-11 - Cargo pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Cargo pumps. 98.30-11 Section 98.30-11 Shipping COAST..., ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Portable Tanks § 98.30-11 Cargo pumps. No person may operate a cargo pump to transfer a product to or from a portable tank unless the pump...

46 CFR 108.471 - Water pump.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Water pump. 108.471 Section 108.471 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Foam Extinguishing Systems § 108.471 Water pump. Each water pump in a foam extinguishing...

Small Scroll Pump for Cryogenic Liquids, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The innovation is a compact, reliable, light weight, electrically driven pump capable of pumping cryogenic liquids, based on scroll pump technology. This pump will...

Resorption heat pump

International Nuclear Information System (INIS)

Vasiliev, L.L.; Mishkinis, D.A.; Antukh, A.A.; Kulakov, A.G.; Vasiliev, L.L.

2004-01-01

Resorption processes are based on at least two solid-sorption reactors application. The most favorable situation for the resorption heat pumps is the case, when the presence of a liquid phase is impossible. From simple case--two reactors with two salts to complicated system with two salts + active carbon fiber (fabric) and two branch of the heat pump acting out of phase to produce heat and cold simultaneously, this is the topic of this research program

Direct solar-pumped lasers

Science.gov (United States)

Lee, J. H.; Shiu, Y. J.; Weaver, W. R.

1980-01-01

The feasibility of direct solar pumping of an iodine photodissociation laser at lambda = 1.315 microns was investigated. Threshold inversion density and effect of elevated temperature (up to 670 K) on the laser output were measured. These results and the concentration of solar radiation required for the solar pumped iodine laser are discussed.

Flow pumping system for physiological waveforms.

Science.gov (United States)

Tsai, William; Savaş, Omer

2010-02-01

A pulsatile flow pumping system is developed to replicate flow waveforms with reasonable accuracy for experiments simulating physiological blood flows at numerous points in the body. The system divides the task of flow waveform generation between two pumps: a gear pump generates the mean component and a piston pump generates the oscillatory component. The system is driven by two programmable servo controllers. The frequency response of the system is used to characterize its operation. The system has been successfully tested in vascular flow experiments where sinusoidal, carotid, and coronary flow waveforms are replicated.

Characterization of integron mediated antimicrobial resistance in Salmonella isolated from diseased swine

Science.gov (United States)

White, David G.; Zhao, Shaohua; McDermott, Patrick F.; Ayers, Sherry; Friedman, Sharon; Sherwood, Julie; Breider-Foley, Missy; Nolan, Lisa K.

2003-01-01

Forty-two Salmonella isolates obtained from diseased swine were genetically characterized for the presence of specific antimicrobial resistance mechanisms. Twenty of these isolates were characterized as S. Typhimurium DT104 strains. Pulsed-field gel electrophoresis was used to determine genetic relatedness and revealed 20 distinct genetic patterns among the 42 isolates. However, all DT104 isolates fell within 2 closely related genetic clusters. Other Salmonella isolates were genetically grouped together according to serotype. All DT104 isolates displayed the penta-resistance phenotype to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline. Resistance to sulfamethoxazole, tetracycline, streptomycin, kanamycin, and ampicillin was most common among the non-DT104 Salmonella isolates. All DT104 strains contained 2 chromosomal integrons of 1000 and 1200 base pairs. The DNA sequencing revealed that the 2 integrons contained genes encoding a resistance to streptomycin and ampicillin, respectively. None of the non-DT104 strains showed the same pattern, although several strains possessed integrons of 1000 base pairs or larger. However, the majority of non-DT104 Salmonella strains did not possess any integrons. Two Salmonella isolates displayed tolerance to the organic solvent cyclohexane, indicating the possibility that they are overexpressing chromosomal regulatory genes marA or soxS or the associated multidrug efflux pump, acrAB. This research suggests that integrons contribute to antimicrobial resistance among specific swine Salmonella serotypes; however, they are not as widely disseminated among non-Typhimurium swine Salmonella serotypes as previously thought. PMID:12528827

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.

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.

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].

New and future heat pump technologies

Science.gov (United States)

Creswick, F. A.

It is not possible to say for sure what future heat pumps will look like, but there are some interesting possibilities. In the next five years, we are likely to see US heat pumps with two kinds of innovations: capacity modulation and charge control. Capacity modulation will be accomplished by variable-speed compressor motors. The objective of charge control is to keep the refrigerant charge in the system where it belongs for best performance; there are probably many ways to accomplish this. Charge control will improve efficiency and durability; capacity modulation will further improve efficiency and comfort. The Stirling cycle heat pump has several interesting advantages, but it is farther out in time. At present, we don't know how to make it as efficient as the conventional vapor-compression heat pump. Electric utility people should be aware that major advances are being made in gas-fired heat pumps which could provide strong competition in the future. However, even a gas-fired heat pump has a substantial auxiliary electric power requirement. The resources needed to develop advanced heat pumps are substantial and foreign competition will be intense. It will be important for utilities, manufacturers, and the federal government to work in close cooperation.

Direct solar-pumped iodine laser amplifier

Science.gov (United States)

Han, Kwang S.; Hwang, In Heon

1990-01-01

The optimum conditions of a solar pumped iodine laser are found in this research for the case of a continuous wave operation and a pulsed operation. The optimum product of the pressure(p) inside the laser tube and the tube diameter(d) was pd=40 approx. 50 torr-cm on the contrary to the case of a high intensity flashlamp pumped iodine laser where the optimum value of the product is known to be pd=150 torr-cm. The pressure-diameter product is less than 1/3 of that of the high power iodine laser. During the research period, various laser materials were also studied for solar pumping. Among the laser materials, Nd:YAG is found to have the lowest laser threshold pumping intensity of about 200 solar constant. The Rhodamine 6G was also tested as the solar pumped laser material. The threshold pumping power was measured to be about 20,000 solar constant. The amplification experiment for a continuously pumped iodine laser amplifier was performed using Vortek solar simulator and the amplification factors were measured for single pass amplification and triple pass amplification of the 15 cm long amplifier tube. The amplification of 5 was obtained for the triple pass amplification.

Improvements in or relating to pumps

Energy Technology Data Exchange (ETDEWEB)

Strong, R E; Boyle, K

1976-06-30

A pump is described that has what is termed a fluid diode in the inlet and outlet. Each such diode has non-moving parts and is operable to allow fluid to flow therethrough easily in one direction and to give restricted flow in the reverse direction. A suction leg is provided, connected to an ejector having a passage for compressed gas, and a valve is provided in the passage downstream of the ejector operable to open and close the passage periodically, thereby creating alternate negative and positive pumping pressures within the pump chamber. The valve may take the form of a solenoid valve and may include electrically linked means for sensing liquid levels. The pump is stated to be particularly attractive for plants in which it is desirable to avoid pump maintenance. Examples of its application includes the transfer of toxic and radioactive liquids. The exhaust from the ejector can be fed into a containment vessel from which it can be extracted through a normal venting system for plant handling such materials. It is also suitable for sludge pumping. The solenoid valve does not come into contact with the fluid being pumped, and can be located so that it is accessible for maintenance. Stainless steel is normally a convenient constructional material.

Developing a System for Integraded Automatic Control of Mutiple Infusion Pumps : The Multiplex infusion system

NARCIS (Netherlands)

Doesburg, Frank

2013-01-01

Most errors in ICUs are related to intravenous (IV) therapy. Previous studies suggested that hard to operate infusion pumps and the high cognitive workload for ICU nurses contribute to these errors. Conventional IV therapy requires separate lumens for incompatible IV drugs. This often requires the

Pump Propels Liquid And Gas Separately

Science.gov (United States)

Harvey, Andrew; Demler, Roger

1993-01-01

Design for pump that handles mixtures of liquid and gas efficiently. Containing only one rotor, pump is combination of centrifuge, pitot pump, and blower. Applications include turbomachinery in powerplants and superchargers in automobile engines. Efficiencies lower than those achieved in separate components. Nevertheless, design is practical and results in low consumption of power.

Experimental performance analysis of a direct-expansion ground source heat pump in Xiangtan, China

International Nuclear Information System (INIS)

Yang, Wei

2013-01-01

The DX GSHP (direct-expansion ground source heat pump), which uses a buried copper piping network through which refrigerant is circulated, is one type of GSHP (ground source heat pump). This study investigates the performance characteristics of a vertical U-bend direct-expansion ground source (geothermal) heat pump system (DX GSHPS) for both heating and cooling. Compared with the conventional GCHP (ground coupled heat pump) system, the DX GSHP system is more efficient, with lower thermal resistance in the GHE (ground heat exchanger) and a lower (higher) condensing (evaporating) temperature in the cooling (heating) mode. In addition, the system performance of the whole DX GSHP system is also higher than that of the conventional GCHP system. A DX GSHP system in Xiangtan, China with a U-bend ground heat exchanger 42 m deep with a nominal outside diameter of 12.7 mm buried in a water well was tested and analysed. The results showed that the performance of this system is very high. The maximum (average) COPs of the system were found to be 6.08 (4.73) and 6.32 (5.03) in the heating and cooling modes, respectively. - Highlights: • The reasons for the higher performance of the DX GSHP (direct-expansion ground source heat pump) are analysed theoretically compared with the conventional GCHP (ground coupled heat pump). • The experimental performance of a DX GSHP system is investigated, which makes a valuable contribution to the literature. • The study is helpful in demonstrating the energy efficiency of the DX GSHP system

40 CFR 65.116 - Quality improvement program for pumps.

Science.gov (United States)

2010-07-01

... (for example, piston, horizontal or vertical centrifugal, gear, bellows); pump manufacturer; seal type and manufacturer; pump design (for example, external shaft, flanged body); materials of construction... program. (4) Pump or pump seal inspection. The owner or operator shall inspect all pumps or pump seals...

Multi-objective optimization of water quality, pumps operation, and storage sizing of water distribution systems.

Science.gov (United States)

Kurek, Wojciech; Ostfeld, Avi

2013-01-30

A multi-objective methodology utilizing the Strength Pareto Evolutionary Algorithm (SPEA2) linked to EPANET for trading-off pumping costs, water quality, and tanks sizing of water distribution systems is developed and demonstrated. The model integrates variable speed pumps for modeling the pumps operation, two water quality objectives (one based on chlorine disinfectant concentrations and one on water age), and tanks sizing cost which are assumed to vary with location and diameter. The water distribution system is subject to extended period simulations, variable energy tariffs, Kirchhoff's laws 1 and 2 for continuity of flow and pressure, tanks water level closure constraints, and storage-reliability requirements. EPANET Example 3 is employed for demonstrating the methodology on two multi-objective models, which differ in the imposed water quality objective (i.e., either with disinfectant or water age considerations). Three-fold Pareto optimal fronts are presented. Sensitivity analysis on the storage-reliability constraint, its influence on pumping cost, water quality, and tank sizing are explored. The contribution of this study is in tailoring design (tank sizing), pumps operational costs, water quality of two types, and reliability through residual storage requirements, in a single multi-objective framework. The model was found to be stable in generating multi-objective three-fold Pareto fronts, while producing explainable engineering outcomes. The model can be used as a decision tool for both pumps operation, water quality, required storage for reliability considerations, and tank sizing decision-making. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

46 CFR 76.10-5 - Fire pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Fire pumps. 76.10-5 Section 76.10-5 Shipping COAST GUARD..., Details § 76.10-5 Fire pumps. (a) Vessels shall be equipped with independently driven fire pumps in accordance with table 76.10-5(a). Table 76.10-5(a) Gross tons Over Not over Minimum number of pumps...

PUMP: analog-hybrid reactor coolant hydraulic transient model

International Nuclear Information System (INIS)

Grandia, M.R.

1976-03-01

The PUMP hybrid computer code simulates flow and pressure distribution; it is used to determine real time response to starting and tripping all combinations of PWR reactor coolant pumps in a closed, pressurized, four-pump, two-loop primary system. The simulation includes the description of flow, pressure, speed, and torque relationships derived through pump affinity laws and from vendor-supplied pump zone maps to describe pump dynamic characteristics. The program affords great flexibility in the type of transients that can be simulated

Experimental study of membrane pump for plasma devices

International Nuclear Information System (INIS)

Suzuki, Hajime; Ohyabu, Nobuyoshi; Nakamura, Yukio; Sagara, Akio; Motojima, Osamu; Livshits, A.; Notkin, M.; Busnyuk, A.; Komatsu, Kazuyuki

1998-01-01

Recycling control is a key to improve fusion plasma performance. The membrane pump has potential advantages for hydrogen pumping in fusion devices. However, there are unsolved issues for using membrane pump in LHD (Large Helical Device). The first issue is characteristics of the membrane pump under high incident hydrogen atom flux. The second issue is relationship between the surface condition and the pumping efficiency. Impurities from plasma may change the surface condition of the membrane. In order to solve these issues, a membrane pump system was fabricated and installed in a linear plasma device at NIFS (National Institute for Fusion Science). The membrane pump was successfully operated. (author)

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.

Nuclear power/water pumping-up composite power plant

International Nuclear Information System (INIS)

Okamura, Kiyoshi.

1995-01-01

In a nuclear power/water pumping-up composite power plant, a reversible pump for pumping-up power generation connected to a steam turbine is connected to an upper water reservoir and a lower water reservoir. A pumping-up steam turbine for driving the turbine power generator, a hydraulic pump for driving water power generator by water flowing from the upper water reservoir and a steam turbine for driving the pumping-up pump by steams from a nuclear reactor are disposed. When power demand is small during night, the steam turbine is rotated by steams of the reactor, to pump up the water in the lower water reservoir to the upper water reservoir by the reversible pump. Upon peak of power demand during day time, power is generated by the steams of the reactor, as well as the reversible pump is rotated by the flowing water from the upper water reservoir to conduct hydraulic power generation. Alternatively, hydraulic power generation is conducted by flowing water from the upper reservoir. Since the number of energy conversion steps in the combination of nuclear power generation and pumping-up power generation is reduced, energy loss is reduced and utilization efficiency can be improved. (N.H.)

5l/h pump for dosing corrosion radioactive liquids

International Nuclear Information System (INIS)

Przybylovich, S.; Shraer, V.; Chermak, R.

1977-01-01

The technical requirements, design and main technical characteristics of the pump for dosing corrosion and radioactive liquids with capacity up to 5 l/h are described. The design is based on the popular sixvertical split casing pump. The pump has four separate pump membrane type blocks with nonstraight hydraulic membrane control. The membranes are made of the cold worked CrNi(18/10)type stainless steel with thickness up to 0.1 mm and have the lifetime up to 3000 hours. The remote pump heads are used for pumping radioactive fluids when the pumping goes behind the safe wall, separating the pump from a hot lab. The tests showed that the pump secures the satisfactory accuracy of dozing and uniformity of pumping and that it is really possible to achieve the required life time of 10000 hours by this pump

Wind pumps for agriculture: Cost and environmental benefits (comparisons with electric and combustion engine driven pumps)

International Nuclear Information System (INIS)

Piccoli, F.

1991-01-01

After describing initial and running costs of a group of wind-pumps, the author calculates and compares, as far as agricultural and zootechnical purposes are concerned, the costs for each cubic meter of water extracted through wind-powered, electric and internal-combustion engines. The comparisons clearly show, under adequate wind conditions, that wind-pumps are economically more suitable than electric and motor pumps with similar delivery heads

Feed pumps for a NPP

International Nuclear Information System (INIS)

Rzhebaev, Eh.E.; Zhukov, V.M.; Evtushenko, A.A.

1977-01-01

Given is a brief description of results of designing and testing the PE850-65 and SPE1650-75 pilot feed pumps for 440 MWe pressurized water reactors and for 1000 MWe boiling water reactors. Described is a bench-mark facility for the SPE1650-75 pump with full-scale parameters. The adjustment results of the preconnected axial wheel of the 1PE1650-75 pump during the service life tests of a pilot pump have been given. Practical results on new methods of the preconnected axial wheel protection have been obtained. The design criteria developed provide for the long life time within the proven range of circular velocities. Confirmed is a possibility of carrying out advanced tests for estimating the cavitation destruction intensity using the vibration due to cavitation

Fabrication of micro metallic valve and pump

Science.gov (United States)

Yang, Ming; Kabasawa, Yasunari; Ito, Kuniyoshi

2010-03-01

Fabrication of micro devices by using micro metal forming was proposed by the authors. We developed a desktop servo-press machine with precise tooling system. Precise press forming processes including micro forging and micro joining has been carried out in a progressive die. In this study, micro metallic valve and pump were fabricated by using the precise press forming. The components are made of sheet metals, and assembled in to a unit in the progressive die. A micro check-valve with a diameter of 3mm and a length of 3.2mm was fabricated, and the property of flow resistance was evaluated. The results show that the check valve has high property of leakage proof. Since the valve is a unit parts with dimensions of several millimeters, it has advantage to be adapted to various pump design. Here, two kinds of micro pumps with the check-valves were fabricated. One is diaphragm pump actuated by vibration of the diaphragm, and another is tube-shaped pump actuated by resonation. The flow quantities of the pumps were evaluated and the results show that both of the pumps have high pumping performance.

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.

Circulating water pumps for nuclear power stations

International Nuclear Information System (INIS)

Satoh, Hiroshi; Ohmori, Tsuneaki

1979-01-01

Shortly, the nuclear power station with unit power output of 1100 MW will begin the operation, and the circulating water pumps manufactured recently are those of 2.4 to 4 m bore, 840 to 2170 m 3 /min discharge and 2100 to 5100 kW driving power. The circulating water pumps are one of important auxiliary machines, because if they fail, power generation capacity lowers immediately. Enormous quantity of cooling water is required to cool condensers, therefore in Japan, sea water is usually used. As siphon is formed in circulating water pipes, the total head of the pumps is not very high. The discharge of the pumps is determined so as to keep the temperature rise of discharged water lower than 7 deg. C. The quantity of cooling water for nuclear power generation is about 50% more as compared with thermal power generation because of the difference in steam conditions. The total head of the pumps is normally from 8 to 15 m. The circulating water pumps rarely stop after they started the operation, therefore it is economical to determine the motor power so that it can withstand 10% overload for a short period, instead of large power. At present, vertical shaft, oblique flow circulating water pumps are usually employed. Recently, movable blade pumps are adopted. The installation, construction and materials of the pumps and the problems are described. (Kako, I.)

46 CFR 169.654 - Bilge pumps.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Bilge pumps. 169.654 Section 169.654 Shipping COAST... Electrical Bilge Systems § 169.654 Bilge pumps. (a) Vessels of less than 65 feet in length must have a portable hand bilge pump having a maximum capacity of 5 gpm. (b) In addition to the requirements of...

Pumping Characteristics of the DIII-D Cryopump

International Nuclear Information System (INIS)

A.S. Bozek; C.B. Baxi; R.W. Callis; M.A. Mahdavi; R.C. O'Neill; E.E. Reis

1999-01-01

Beginning in 1992, the first of the DIII-D divertor baffles and cryocondensation pumps was installed. This open divertor configuration, located on the outermost floor of the DIII-D vessel, includes a cryopump with a predicted pumping speed of 50,000 ell/s excluding obstructions such as support hardware. Taking the pump structural and support characteristics into consideration, the corrected pumping speed for D 2 is 30,000 ell/s [1]. In 1996, the second divertor baffle and cryopump were installed. This closed divertor structure, located on the outermost ceiling of the DIII-D vessel, has a cryopump with a predicted pumping speed of 32,000 ell/s. In the fall of 1999, the third divertor baffle and cryopump will be installed. This divertor structure will be located on the 45 o angled corner on the innermost ceiling of the DIII-D vessel, known as the private flux region of the plasma configuration. With hardware supports factored into the pumping speed calculation, the private flux cryopump is expected to have a pumping speed of 15,000 ell/s. There was question regarding the effectiveness of the private flux cryopump due to the close proximity of the private flux baffle. This led to a conductance calculation study of the impact of rotating the cryopump aperture by 180 o to allow for greater particle and gas exhaust into the cryopump's helium panel. This study concluded that the cost and schedule impact of changing the private flux cryopump orientation and design did not warrant the possible 20% (3,000 ell/s) increase in pumping ability gained by rotating the cryopump aperture 180 o . The comparison of pumping speed of the first two cryocondensation pumps with the measured results will be presented as well as the calculation of the pumping speed for the private flux cryopump now being installed

Inducer pumps for liquid metal reactor plants

International Nuclear Information System (INIS)

Jackson, E.D.

2002-01-01

Pumps proposed for liquid metal reactor plants typically use centrifugal impellers as the rotating element and are required to maintain a relatively low speed to keep the suction specific speed low enough to operate at the available net positive suction head (HPSH) and to avoid cavitation damage. These low speeds of operation require that the pump diameter increase and/or multiple stages be used to achieve the design head. This frequently results in a large, heavy, complex pump design. In addition, the low speed results in a larger drive motor size so that the resultant penalty to the plant designer is multiplied. The heavier pump can also result in further complications as, e.g., the difficulty in maintaining the first critical speed sufficiently above the pump operating range to provide margin for rotor dynamic stability. To overcome some of these disadvantages, it was proposed the use of inducer pumps for Liquid Metal Fast Breeder Reactor (LMFBR) plants. This paper discusses some of the advantages of the inducer pump and the development history of designing and testing these pumps both in water and sodium. The inducer pump is seen to be a sound concept with a strong technology base derived from the aerospace and ship propulsion industries. The superior suction performance capability of the inducer offers significant system design advantages, primarily a smaller, lighter weight, less complex pump design with resulting saving in cost. Extensive testing of these pumps has been conducted in both sodium and water to demonstrate the long-life capability with no cavitation damage occurring in those designs based on Rockwell's current design criteria. These tests have utilized multiple inspection and measurement approaches to accurately assess and identify any potential for cavitation damage, and these approaches have all concluded that no damage is occurring. Therefore, it is concluded that inducer pumps can be safely designed for long life operation in sodium with

Double-shell tank annulus pumping alternative evaluation

International Nuclear Information System (INIS)

RIESENWEBER, S.D.

1999-01-01

This engineering evaluation compares five alternative schemes for maintaining emergency annulus pumping equipment in a reliable condition. The five schemes are: (1) continue status quo; (2) periodic pump removal and run-in; (3) periodic in-place limited maintenance; (4) uninstalled ready spares; and (5) expanded mission of Single-Shell Tank Emergency Pumping Trailer. Each alternative is described, the pros and cons identified, and rough order of magnitude life-cycle costs computed. The alternatives are compared using weighted evaluation criteria. The evaluation concludes that staging adjustable length submersible pumps in the Single-Shell Tank Emergency Pumping Trailer has the best cost-benefit characteristics

End-pumped Nd:YVO4 laser with reduced thermal lensing via the use of a ring-shaped pump beam.

Science.gov (United States)

Lin, Di; Andrew Clarkson, W

2017-08-01

A simple approach for alleviating thermal lensing in end-pumped solid-state lasers using a pump beam with a ring-shaped intensity distribution to decrease the radial temperature gradient is described. This scheme has been implemented in a diode-end-pumped Nd:YVO 4 laser yielding 14 W of TEM 00 output at 1.064 μm with a corresponding slope efficiency of 53% and a beam propagation factor (M 2 ) of 1.08 limited by available pump power. By comparison, the same laser design with a conventional quasi-top-hat pump beam profile of approximately equal radial extent yielded only 9 W of output before the power rolled over due to thermal lensing. Further investigation with the aid of a probe beam revealed that the thermal lens power was ∼30% smaller for the ring-shaped pump beam compared to the quasi-top-hat beam. The implications for further power scaling in end-pumped laser configurations are considered.

Use of ultrafast dispersed pump-dump-probe and pump-repump-probe spectroscopies to explore the light-induced dynamics of peridinin in solution

NARCIS (Netherlands)

Papagiannakis, E.; Vengris, M.; Larsen, D.S.; van Stokkum, I.H.M.; Hiller, R.G.; van Grondelle, R.

2006-01-01

Optical pump-induced dynamics of the highly asymmetric carotenoid peridinin in methanol was studied by dispersed pump-probe, pump-dump-probe, and pump-repump-probe transient absorption spectroscopy in the visible region. Dispersed pump-probe measurements show that the decay of the initially excited

Walking beam pumping unit system efficiency measurements

International Nuclear Information System (INIS)

Kilgore, J.J.; Tripp, H.A.; Hunt, C.L. Jr.

1991-01-01

The cost of electricity used by walking beam pumping units is a major expense in producing crude oil. However, only very limited information is available on the efficiency of beam pumping systems and less is known about the efficiency of the various components of the pumping units. This paper presents and discusses measurements that have been made on wells at several Shell locations and on a specially designed walking beam pump test stand at Lufkin Industries. These measurements were made in order to determine the overall system efficiency and efficiency of individual components. The results of this work show that the overall beam pumping system efficiency is normally between 48 and 58 percent. This is primarily dependent on the motor size, motor type, gearbox size, system's age, production, pump size, tubing size, and rod sizes

Canned motor pumps at Heavy Water Project, Baroda

International Nuclear Information System (INIS)

Batra, R.K.; Waishampayan, S.C.

1981-01-01

Pumps to be used in heavy water plants must be reliable and should require negligible maintenance, because most of them are totally unapproachable under normal circumstances. Canned motor pumps fulfil these requirements. Their design features are described briefly. The details of: (1) the pumps in the isotopic exchange tower and (2) pumps for liquid ammonia and catalyst are given. Problems faced during commissioning of such pumps in Baroda Heavy Water Project were bulging of rotors of tower pumps, bulging of stators, jamming and failure of bearings. Solution of these problems is described. (M.G.B.)

Proton pump inhibitors reduce the size and acidity of the acid pocket in the stomach

NARCIS (Netherlands)

Rohof, Wout O.; Bennink, Roelof J.; Boeckxstaens, Guy E.

2014-01-01

The gastric acid pocket is believed to be the reservoir from which acid reflux events originate. Little is known about how changes in position, size, and acidity of the acid pocket contribute to the therapeutic effect of proton pump inhibitors (PPIs) in patients with gastroesophageal reflux disease

Replacement Saltwell Pumping System Document Bibliography

International Nuclear Information System (INIS)

BELLOMY, J.R.

2000-01-01

This document bibliography is prepared to identify engineering documentation developed during the design of the Replacement Saltwell Pumping System. The bibliography includes all engineering supporting documents and correspondence prepared prior to the deployment of the system in the field. All documents referenced are available electronically through the Records Management Information System (RMIS). Major components of the Replacement Saltwell Pumping System include the Sundyne Canned Motor Pump, the Water Filter Skid, the Injection Water Skid and the Backflow Preventer Assembly. Drawing H-14-104498 provides an index of drawings (fabrication details, PandIDs, etc.) prepared to support development of the Replacement Saltwell Pumping System. Specific information pertaining to new equipment can be found in Certified Vendor Information (CVI) File 50124. This CVI file has been established specifically for new equipment associated with the Replacement Saltwell Pumping System

Quantitative pump-induced wavefront distortions in laser-diode- and flash-lamp-pumped Nd:YLF laser rods

International Nuclear Information System (INIS)

Skeldon, M.D.; Saager, R.B.; Seka, W.

1999-01-01

Detailed interferometric measurements of the induced thermal distortions due to laser-diode and xenon flashlamp pumping of Nd:YLF are presented. The thermal distortions are quantified in terms of the primary aberrations of defocus, astigmatism, coma, and spherical. Defocus and astigmatism are shown to dominate the thermal aberrations. The measured defocus and astigmatism are converted to the conventional thermal-focal lengths in two perpendicular directions with respect to the Nd:YLF crystalline c axis for each of the two polarization states σ and π. A comparison of the thermal-focal lengths measured with the xenon flashlamp- and laser-diode-pumped rods is given when the rods are pumped to the same small-signal gain. The authors calculate effective dioptric-power coefficients from the data for comparison to those reported in the literature for krypton-flashlamp pumping. A thermal-time constant of 1.5 s is measured for the laser-diode-pumped Nd:YLF laser rod

A three dimensional calculation of neutron streaming through ITER tokamak pumping ducts with the Monte Carlo code TRIPOLI-2

International Nuclear Information System (INIS)

Bresard, I.; Diop, C.M.; Giancarli, L.; Gervaise, F.

1991-01-01

In the frame of the ITER tokamak project, the streaming of neutrons through pumping ducts up to the properly so called pumping system is studied. The gas evacuation device of the ITER plasma consists of a set of vacuum pumps which are located in a room which is outside the main machine building. These pumps receive the exhaust gas through several pumping ducts with a cross section of about four square meters and a length of about ten meters. Although insensitive to the magnetic field, the 14 MeV neutrons from plasma D-T thermonuclear reactions can penetrate in the divertor and reach the room pumping device by propagation through the bent ducts. Different components of this system, such as the bellows, turbomolecular pumps, etc., are irradiated and that raises radiation problems. In this study we determine, by using 3D Monte Carlo transport code TRIPOLI-2, neutron fluxes, dose rates and heatings due to neutrons which have streamed out the plasma through the bent ducts, at several points of the pumping room. Results show the neutron flux attenuation reachs a factor 10 -5 from plasma chamber to the pumping hall; the neutron heatings are estimated to 1.9x10 -3 W/cm 3 in bellow stainless steel at duct entrance, and 8x10 -7 W/cm 3 in the turbopumping stainless steel structure, inside pumping hall. The neutron fluxes obtained will be used to compute gamma source produced by radiative, inelastic process and gamma rays from formed activation products. Then, the knowledge of gamma source will allow to compute gamma dose rate and heating. The dose rates and heatings obtained will contribute to the definition of the ITER pumping system technical options and to establish pumping hall access conditions, also. (orig.)

Method and apparatus for protection of pump systems

International Nuclear Information System (INIS)

Youngborg, L.H.

1987-01-01

This patent describes a nuclear power plant having a fluid-filler reactor vessel with a vapor outflow line for removing vapor from the reactor vessel, and liquid inflow means for injecting liquid to the reactor vessel. The inflow means includes an inflow line, a centrifugal pump disposed along the inflow line having an inlet and an outlet, an induction motor to drive the pump, flow control means along the inflow line between the pump and the reactor vessel from the pump. A means is included for generating a first control signal in response to liquid level in the reactor vessel and net vapor outflow versus liquid inflow with respect to the reactor vessel, the first control signal generating means being effective to generate a first signal to open and a second signal to close the flow control means to maintain liquid level in the vessel within predetermined limits. A pump and pump motor protection apparatus is described comprising: means for measuring the pressure of the liquid in the inlet of the pump; means for measuring the temperature of the liquid in the inlet of the pump; means for determining a required subcooling for the pump at the instantaneous temperature of the liquid in the inlet of the pump; and means for determining the enthalpy of the liquid in the inlet of the pump from the pressure and temperature of the liquid

ALT-I pump limiter experiments

International Nuclear Information System (INIS)

Goebel, D.M.; Conn, R.W.; Campbell, G.A.

1987-09-01

Results from the ALT-I pump limiter experiments in TEXTOR are presented. ALT-I has demonstrated control of the plasma density in a high recycling tokamak by pumping up to 15% of the core efflux. The closed pump limiter designs with restricted entrance geometries to reduce the backflow of neutral gas to the plasma remove over 50% of the ion flux incident on the collection slot. Up to 80% of the entrance ion flux is removed when the edge electron temperature is less than 10 eV and plasma-neutral gas interactions are minimized inside the limiter. Results from a 3-D Monte Carlo neutral gas transport code agree closely with these experimental results. The compound curvature of the head is found to distribute the heat over the surface as predicted in the original designs. Impurity removal experiments demonstrate that significant helium exhaust can be achieved with a pump limiter. During ohmic heating in TEXTOR, the energy and particle confinement times are proportional to the line averaged core density. With ICRH auxiliary heating, tau/sub E/ follow L-mode scaling independent of particle removal by the pump limiter. Pump limiter operation does not directly modify the SOL plasma density and electron temperature, but controls the core plasma density by changing the global recycling at the boundary. The global particle confinement, the particle flux to the limiter, and the edge electron temperature follow the changes in the core density and auxiliary heating power. 25 refs

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.)

Operating pumps on minimum flow

International Nuclear Information System (INIS)

Casada, D.A.; Li, Y.C.

1992-01-01

The Nuclear Regulatory Commission (NRC) staff issued Information Notice (IN) 87-59 to alert all licensees to two miniflow design concerns identified by Westinghouse. The first potential problem discussed in this IN involves parallel pump operation. If the head/capacity curve of one of the parallel pumps is greater than the other, the weaker pump may be dead-headed when the pumps are operating at low-flow conditions. The other problem related to potential pump damage as a result of hydraulic instability during low-flow operation. In NRC Bulletin 88-04, dated May 5, 1988, the staff requested all licensees to investigate and correct, as applicable, the two miniflow design concerns. The staff also developed a Temporary Instruction, Tl 2515/105, dated January 29, 1990 to inspect for the adequacy of licensee response and follow-up actions to NRC Bulletin 88-04. Oak Ridge National Laboratory has reviewed utility responses to Bulletin 88-04 under auspices of the NRC's Nuclear Plant Aging Research Program, and participated in several NRC inspections. Examples of actions that have been taken, an assessment of the overall industry response, and resultant conclusions and recommendations are presented

46 CFR 109.329 - Fire pumps.

Science.gov (United States)

2010-10-01

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

Heat pump heating with heat pumps driven by combustion engines or turbines

Energy Technology Data Exchange (ETDEWEB)

Hein, K

1977-01-27

The heat pump described is driven by a gas Otto cycle engine, or a gas- or light- or heavy-oil fired Diesel engine. The claim refers to the use of waste heat of the engines by feeding into the input circuit of the heat pump. In addition, a drive by an electrical motor-generator or power production can be selected at times of peak load in the electrical supply network.

Transverse pumped laser amplifier architecture

Science.gov (United States)

Bayramian, Andrew James; Manes, Kenneth; Deri, Robert; Erlandson, Al; Caird, John; Spaeth, Mary

2013-07-09

An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

Tunable diode-pumped-LNA laser

International Nuclear Information System (INIS)

Cassimi, A.; Hardy, V.; Hamel, J.; Leduc, M.

1987-01-01

Diode-pumped crystals provided recently new compact laser devices. We report the first end pumping of a La x Nd 1-x MgAl 11 O 19 (LNA) crystal using a 200mW diode array (Spectra Diode Lab). We also report the first results obtained with a 1mW diode (SONY). This C.W. laser can be tuned from 1.048μm to 1.086μm. Without selective elements in the cavity, the laser emits around 1.054μm with a threshold of 24mW and a slope efficiency of 4.4% (output mirror of transmission T = 1%) when pumped by the diode array. With the selective elements, the threshold increases to 100mW and we obtain a power of 4mW for a pump power of 200mW

77 FR 2957 - Application for Manufacturing Authority, Liberty Pumps, Inc. (Submersible and Water Pumps...

Science.gov (United States)

2012-01-20

... formally filed on January 12, 2012. The Liberty Pumps, Inc., facility (108 employees, 9.1 acres, production... from abroad (representing 30 to 40% of the value of the finished pumps) include: Plastic (polyamide) resins, plastic boxes/cases/tanks, articles of plastic, rubber gaskets/seals, labels, wood pallets...

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 ...

Transient two-phase performance of LOFT reactor coolant pumps

International Nuclear Information System (INIS)

Chen, T.H.; Modro, S.M.

1983-01-01

Performance characteristics of Loss-of-Fluid Test (LOFT) reactor coolant pumps under transient two-phase flow conditions were obtained based on the analysis of two large and small break loss-of-coolant experiments conducted at the LOFT facility. Emphasis is placed on the evaluation of the transient two-phase flow effects on the LOFT reactor coolant pump performance during the first quadrant operation. The measured pump characteristics are presented as functions of pump void fraction which was determined based on the measured density. The calculated pump characteristics such as pump head, torque (or hydraulic torque), and efficiency are also determined as functions of pump void fractions. The importance of accurate modeling of the reactor coolant pump performance under two-phase conditions is addressed. The analytical pump model, currently used in most reactor analysis codes to predict transient two-phase pump behavior, is assessed

Factors governing sustainable groundwater pumping near a river.

Science.gov (United States)

Zhang, Yingqi; Hubbard, Susan; Finsterle, Stefan

2011-01-01

The objective of this paper was to provide new insights into processes affecting riverbank filtration (RBF). We consider a system with an inflatable dam installed for enhancing water production from downstream collector wells. Using a numerical model, we investigate the impact of groundwater pumping and dam operation on the hydrodynamics in the aquifer and water production. We focus our study on two processes that potentially limit water production of an RBF system: the development of an unsaturated zone and riverbed clogging. We quantify river clogging by calibrating a time-dependent riverbed permeability function based on knowledge of pumping rate, river stage, and temperature. The dynamics of the estimated riverbed permeability reflects clogging and scouring mechanisms. Our results indicate that (1) riverbed permeability is the dominant factor affecting infiltration needed for sustainable RBF production; (2) dam operation can influence pumping efficiency and prevent the development of an unsaturated zone beneath the riverbed only under conditions of sufficient riverbed permeability; (3) slow river velocity, caused by dam raising during summer months, may lead to sedimentation and deposition of fine-grained material within the riverbed, which may clog the riverbed, limiting recharge to the collector wells and contributing to the development of an unsaturated zone beneath the riverbed; and (4) higher river flow velocities, caused by dam lowering during winter storms, scour the riverbed and thus increase its permeability. These insights can be used as the basis for developing sustainable water management of a RBF system. Journal compilation © 2010 National Ground Water Association. No claim to original US government works.

Verification Test of Hydraulic Performance for Reactor Coolant Pump

Energy Technology Data Exchange (ETDEWEB)

Park, Sang Jun; Kim, Jae Shin; Ryu, In Wan; Ko, Bok Seong; Song, Keun Myung [Samjin Ind. Co., Seoul (Korea, Republic of)

2010-01-15

According to this project, basic design for prototype pump and model pump of reactor coolant pump and test facilities has been completed. Basic design for prototype pump to establish structure, dimension and hydraulic performance has been completed and through primary flow analysis by computational fluid dynamics(CFD), flow characteristics and hydraulic performance have been established. This pump was designed with mixed flow pump having the following design requirements; specific velocity(Ns); 1080.9(rpm{center_dot}m{sup 3}/m{center_dot}m), capacity; 3115m{sup 3}/h, total head ; 26.3m, pump speed; 1710rpm, pump efficiency; 77.0%, Impeller out-diameter; 349mm, motor output; 360kw, design pressure; 17MPaG. The features of the pump are leakage free due to no mechanical seal on the pump shaft which insures reactor's safety and law noise level and low vibration due to no cooling fan on the motor which makes eco-friendly product. Model pump size was reduced to 44% of prototype pump for the verification test for hydraulic performance of reactor coolant pump and was designed with mixed flow pump and canned motor having the following design requirements; specific speed(NS); 1060.9(rpm{center_dot}m{sup 3}/m{center_dot}m), capacity; 539.4m{sup 3}/h, total head; 21.0m, pump speed; 3476rpm, pump efficiency; 72.9%, Impeller out-diameter; 154mm, motor output; 55kw, design pressure; 1.0MPaG. The test facilities were designed for verification test of hydraulic performance suitable for pump performance test, homologous test, NPSH test(cavitation), cost down test and pressure pulsation test of inlet and outlet ports. Test tank was designed with testing capacity enabling up to 2000m{sup 3}/h and design pressure 1.0MPaG. Auxiliary pump was designed with centrifugal pump having capacity; 1100m{sup 3}/h, total head; 42.0m, motor output; 190kw

Pump

International Nuclear Information System (INIS)

Mole, C.J.

1983-01-01

An electromagnetic pump for circulating liquid -metal coolant through a nuclear reactor wherein opposite walls of a pump duct serve as electrodes to transmit current radially through the liquid-metal in the ducts. A circumferential electric field is supplied to the liquid-metal by a toroidal electromagnet which has core sections interposed between the ducts. The windings of the electromagnet are composed of metal which is superconductive at low temperatures and the electromagnet is maintained at a temperature at which it is superconductive by liquid helium which is fed through the conductors which supply the excitation for the electromagnet. The walls of the ducts joining the electrodes include metal plates insulated from the electrodes backed up by insulators so that they are capable of withstanding the pressure of the liquid-metal. These composite wall structures may also be of thin metal strips of low electrical conductivity backed up by sturdy insulators. (author)

Non-adiabatic pumping in an oscillating-piston model

Science.gov (United States)

Chuchem, Maya; Dittrich, Thomas; Cohen, Doron

2012-05-01

We consider the prototypical "piston pump" operating on a ring, where a circulating current is induced by means of an AC driving. This can be regarded as a generalized Fermi-Ulam model, incorporating a finite-height moving wall (piston) and non-trivial topology (ring). The amount of particles transported per cycle is determined by a layered structure of phase space. Each layer is characterized by a different drift velocity. We discuss the differences compared with the adiabatic and Boltzmann pictures, and highlight the significance of the "diabatic" contribution that might lead to a counter-stirring effect.

Performance evaluation on vacuum pumps using nanolubricants

Energy Technology Data Exchange (ETDEWEB)

Lue, Yeou Feng; Hsu, Yu Chun; Teng, Tun Ping [Dept. of Industrial EducationNational Taiwan Normal University, Taiwan (China)

2016-09-15

This study produced alumina (Al{sub 2}O{sub 3}) nanovacuum-pump lubricants (NVALs) by involving the dispersion of Al{sub 2}O{sub 3} nanoparticles in a vacuum-pump lubricant (VAL) with oleic as a dispersant. Experiments were conducted to evaluate the suspension performance, thermal conductivity, viscosity, specific heat, tribological performance and vacuum-pump performance of the NVALs. The experimental results obtained from the vacuum-pump performance tests show that the NVALs with Al{sub 2}O{sub 3} concentration of 0.2 wt.% and oleic concentration of 0.025 wt.% yielded the lowest electricity consumption, conserving 2.39% of electricity compared with the VAL. No marked difference was observed between the temperatures of the vacuum pump using VAL and NVAL. Furthermore, evacuation (i.e., the minimal pressure of -99.5 kPa) was reached faster by the vacuum pump with the NVALs, and the evacuation time could be reduced by 4.91% under optimal conditions. In addition, the vacuum pump with the NVALs exhibited superior overall effectiveness under relatively lower ambient temperatures.

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

Enhance pump reliability through improved inservice testing

International Nuclear Information System (INIS)

Healy, J.J.

1990-01-01

EPRI has undertaken a study to assess the effectiveness of existing testing programs to accurately monitor and predict performance changes before either pump performance degrades or an actual failure occurs. Anticipated changes in inservice testing techniques are directed towards enhancing the validity of test data, ensuring its repeatability, and avoiding deterioration of the pump assembly. There is a new-found interest in test programs of all types that has occurred, in part, because of an increase in reported pump degradation and pump failure. Inservice testing of pumps, which has long been a basis for assuring operability, has apparently produced an opposite effect; namely, the appearance of a reduction in reliability

Radial loads and axial thrusts on centrifugal pumps