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Sample records for pumped nanolaser based

  1. Surface roughness effects on aluminium-based ultraviolet plasmonic nanolasers

    PubMed Central

    Chung, Yi-Cheng; Cheng, Pi-Ju; Chou, Yu-Hsun; Chou, Bo-Tsun; Hong, Kuo-Bin; Shih, Jheng-Hong; Lin, Sheng-Di; Lu, Tien-Chang; Lin, Tzy-Rong

    2017-01-01

    We systematically investigate the effects of surface roughness on the characteristics of ultraviolet zinc oxide plasmonic nanolasers fabricated on aluminium films with two different degrees of surface roughness. We demonstrate that the effective dielectric functions of aluminium interfaces with distinct roughness can be analysed from reflectivity measurements. By considering the scattering losses, including Rayleigh scattering, electron scattering, and grain boundary scattering, we adopt the modified Drude-Lorentz model to describe the scattering effect caused by surface roughness and obtain the effective dielectric functions of different Al samples. The sample with higher surface roughness induces more electron scattering and light scattering for SPP modes, leading to a higher threshold gain for the plasmonic nanolaser. By considering the pumping efficiency, our theoretical analysis shows that diminishing the detrimental optical losses caused by the roughness of the metallic interface could effectively lower (~33.1%) the pumping threshold of the plasmonic nanolasers, which is consistent with the experimental results. PMID:28045127

  2. Surface roughness effects on aluminium-based ultraviolet plasmonic nanolasers

    NASA Astrophysics Data System (ADS)

    Chung, Yi-Cheng; Cheng, Pi-Ju; Chou, Yu-Hsun; Chou, Bo-Tsun; Hong, Kuo-Bin; Shih, Jheng-Hong; Lin, Sheng-Di; Lu, Tien-Chang; Lin, Tzy-Rong

    2017-01-01

    We systematically investigate the effects of surface roughness on the characteristics of ultraviolet zinc oxide plasmonic nanolasers fabricated on aluminium films with two different degrees of surface roughness. We demonstrate that the effective dielectric functions of aluminium interfaces with distinct roughness can be analysed from reflectivity measurements. By considering the scattering losses, including Rayleigh scattering, electron scattering, and grain boundary scattering, we adopt the modified Drude-Lorentz model to describe the scattering effect caused by surface roughness and obtain the effective dielectric functions of different Al samples. The sample with higher surface roughness induces more electron scattering and light scattering for SPP modes, leading to a higher threshold gain for the plasmonic nanolaser. By considering the pumping efficiency, our theoretical analysis shows that diminishing the detrimental optical losses caused by the roughness of the metallic interface could effectively lower (~33.1%) the pumping threshold of the plasmonic nanolasers, which is consistent with the experimental results.

  3. Plasmon-Assisted Nd(3+)-Based Solid-State Nanolaser.

    PubMed

    Molina, Pablo; Yraola, Eduardo; Ramírez, Mariola O; Tserkezis, Christos; Plaza, José L; Aizpurua, Javier; Bravo-Abad, Jorge; Bausá, Luisa E

    2016-02-10

    Solid-state lasers constitute essential tools in a variety of scientific and technological areas, being available in many different designs. However, although nanolasing has been successfully achieved for dyes and semiconductor gain media associated with plasmonic structures, the operation of solid-state lasers beyond the diffraction limit has not been reported yet. Here, we demonstrate room temperature laser action with subwavelength confinement in a Nd(3+)-based solid-state laser by means of the localized surface plasmon resonances supported by chains of metallic nanoparticles. We show a 50% reduction of the pump power at threshold and a remarkable 15-fold improvement of the slope efficiency with respect to the bulk laser operation. The results can be extended to the large diversity of solid-state lasers with the subsequent impact on their applications.

  4. Quantum theory of a spaser-based nanolaser.

    PubMed

    Parfenyev, Vladimir M; Vergeles, Sergey S

    2014-06-02

    We present a quantum theory of a spaser-based nanolaser, under the bad-cavity approximation. We find first- and second-order correlation functions g(1)(τ) and g(2)(τ) below and above the generation threshold, and obtain the average number of plasmons in the cavity. The latter is shown to be of the order of unity near the generation threshold, where the spectral line narrows considerably. In this case the coherence is preserved in a state of active atoms in contradiction to the good-cavity lasers, where the coherence is preserved in a state of photons. The damped oscillations in g(2)(τ) above the generation threshold indicate the unusual character of amplitude fluctuations of polarization and population, which become interconnected in this case. Obtained results allow to understand the fundamental principles of operation of nanolasers.

  5. Towards Photonic-Plasmonic Integrated Circuits: Study and Fabrication Of Electrically-Pumped Plasmonic Nano-Laser

    NASA Astrophysics Data System (ADS)

    Hseih, Chunhan Michael

    For the next generation of optical communication, Photonic Integrated Circuits (PIC) and optoelectronic integrated circuits has been of great interest because of the possibility of integrating multiple optical components and electronics together to give high performance opto-electronic system on a small chip that can be produced cost-effectively. Integrated semiconductor laser, as the main light source for generating signals in optical communications, is one of the most important function on a photonic integrated circuit. In the recent advancements in nanophotonics, strong confinement of light in strongly-guiding optical waveguide structure comparing to conventional structures, has been used to improve certain performances of on-chip semiconductor lasers and miniaturize the laser device sizes. However, compared to electronics, even with use of nanophotonic device technology, optoelectronic device footprints are still relatively large due to the diffraction limit of light, which poses a limit on the sizes of optoelectronic devices. Plasmonic photonic device area has been an intensive field of research that utilizes plamonic photonic waveguides to confine light smaller than the diffraction limit through the effect of surface plasmon polariton, a coupling between photons and plasmon along a metal-dielectric interface. In this dissertation, an electrically pumped Plasmonic nanolaser has been designed using 2D-FDTD simulation. The nanolaser has the potential of lasing utilizing achievable optical gain in the typical compound (group III-V) semiconductor materials. The laser electrical pumping structure is compatible with device integration on silicon photonics platform utilizing silicon-on-insulator (SOI) substrate. Electrically pumped thin film based laser structure is shown to be realizable with the use of TCO material as transparent electrodes on the waveguide cladding. Indium oxide (In2O3) and Zinc-Indium-Tin-Oxide (ZITO) deposited by ion-beam-assisted deposition

  6. A single dielectric nanolaser

    NASA Astrophysics Data System (ADS)

    Huang, Tsung-Yu; Yen, Ta-Jen

    2016-09-01

    To conquer Ohmic losses from metal and enhance pump absorption efficiency of a nanolaser based on surface plasmon polariton, we theoretically calculate the first magnetic and electric scattering coefficient of a dielectric sphere under a plane wave excitation with a dielectric constant of around 12. From this calculation, we could retrieve both negative effective permittivity and permeability of the sphere simultaneously at frequencies around 153 THz in the aids of Lewin's theory and the power distribution clearly demonstrate the expected negative Goos-Hänchen effect, which usually occurred in a negative refractive waveguide, thus creating two energy vortices to trap incident energy and then promoting the pump absorption efficiency. Meanwhile, a magnetic lasing mode at 167.3 THz is demonstrated and reveals a magnetic dipole resonance mode and a circulating energy flow within the dielectric sphere, providing a possible stopped light feedback mechanism to enable the all-dielectric nanolaser. More importantly, the corresponding mode volume is reduced to 0.01λ3 and a gain threshold of 5.1×103 is obtained. To validate our design of all-dielectric nanolaser, we employ finite-difference-time-domain simulation software to examine the behavior of the nanolaser. From simulation, we could obtain a pinned-down population inversion of 0.001 and a lasing peak at around 166.5 THz, which is very consistent with the prediction of Mie theory. Finally, according to Mie theory, we can regard the all-dielectric nanolaser as the excitation of material polariton and thus could make an analogue between lasing modes of the dielectric and metallic nanoparticles.

  7. Metal-optic and Plasmonic Semiconductor-based Nanolasers

    NASA Astrophysics Data System (ADS)

    Lakhani, Amit Manmohan

    Over the past few decades, semiconductor lasers have relentlessly followed the path towards miniaturization. Smaller lasers are more energy efficient, are cheaper to make, and open up new applications in sensing and displays, among many other things. Yet, up until recently, there was a fundamental problem with making lasers smaller: purely semiconductor lasers couldn't be made smaller than the diffraction limit of light. In recent years, however, metal-based lasers have been demonstrated in the nanoscale that have shattered the diffraction limit. As optical materials, metals can be used to either reflect light (metal-optics) or convert light to electrical currents (plasmonics). In both cases, metals have provided ways to squeeze light beyond the diffraction limit. In this dissertation, I experimentally demonstrated one nanolaser based on plasmonic transduction and another laser based on metal-optic reflection. To create coherent plasmons, I designed a nanolaser based on a plasmonic bandgap defect state inside a surface plasmonic crystal. In a one-dimensional periodic semiconductor beam, I was able to confine surface plasmons by interrupting the periodicity of the crystal. These confined surface plasmons then underwent laser oscillations in effective mode volumes as small as 0.007 cubic wavelengths. At this electromagnetic volume, energy was squeezed 10 times smaller than those possible in similar photonic crystals that do not utilize metal. This demonstration should pave the way for achieving engineered nanolasers with deep-subwavelength mode volumes and enable plasmonic crystals to become attractive platforms for designing plasmons. After achieving large reductions in electromagnetic mode volumes, I switched to a metal-optics-based nanolaser design to further reduce the physical volumes of small light sources. The semiconductor nanopatch laser achieved laser oscillations with subwavelength-scale physical dimensions (0.019 cubic wavelengths) and effective mode

  8. Metal-optic and Plasmonic Semiconductor-based Nanolasers

    DTIC Science & Technology

    2012-05-07

    polaritons (SPPs), however, is less commonly seen. Thus, I will go over basic properties of these SPPs to understand how they might help with nanolaser...Noginov et al. [40]. 2.1.2 Single-Sided Surface Plasmons Besides bulk plasmons, metals can also support surface plasmon polaritons (SPPs). Single-sided...surface plasmon polariton crystal (SPPC or plasmonic crystal). A SPPC is simply a periodic structure on a metal film capable of manipulating surface

  9. Ultrahigh Purcell factor in low-threshold nanolaser based on asymmetric hybrid plasmonic cavity

    PubMed Central

    Wei, Wei; Yan, Xin; Zhang, Xia

    2016-01-01

    A low-threshold nanolaser with all three dimensions at the subwavelength scale is proposed and investigated. The nanolaser is constructed based on an asymmetric hybrid plasmonic F-P cavity with Ag-coated end facets. Lasing characteristics are calculated using finite element method at the wavelength of 1550 nm. The results show that owing to the low modal loss, large modal confinement factor of the asymmetric plasmonic cavity structure, in conjunction with the high reflectivity of the Ag reflectors, a minimum threshold gain of 240 cm−1 is predicted. Furthermore, the Purcell factor as large as 2518 is obtained with optimized structure parameters to enhance rates of spontaneous and stimulated emission. PMID:27616768

  10. Ultrahigh Purcell factor in low-threshold nanolaser based on asymmetric hybrid plasmonic cavity

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Yan, Xin; Zhang, Xia

    2016-09-01

    A low-threshold nanolaser with all three dimensions at the subwavelength scale is proposed and investigated. The nanolaser is constructed based on an asymmetric hybrid plasmonic F-P cavity with Ag-coated end facets. Lasing characteristics are calculated using finite element method at the wavelength of 1550 nm. The results show that owing to the low modal loss, large modal confinement factor of the asymmetric plasmonic cavity structure, in conjunction with the high reflectivity of the Ag reflectors, a minimum threshold gain of 240 cm‑1 is predicted. Furthermore, the Purcell factor as large as 2518 is obtained with optimized structure parameters to enhance rates of spontaneous and stimulated emission.

  11. Dynamics of optically-injected semiconductor nanolasers

    NASA Astrophysics Data System (ADS)

    Sarraute, J.-M.; Schires, K.; LaRochelle, S.; Grillot, F.

    2016-03-01

    We propose a novel rate equation model of an optically-injected semiconductor nanolaser based on an expression of the complex electric field including a novel spontaneous emission term. The latter takes into account the amplification of the zero-point energy of the field as well as the Purcell effect. The modulation response of the optically injection-locked nanolaser is studied for the first time using a small-signal analysis of the model. We then investigate the injection map of the nanolaser and study the 3-dB bandwidth of the nanolaser inside the locking region.

  12. Nano-laser on silicon quantum dots

    NASA Astrophysics Data System (ADS)

    Huang, Wei-Qi; Liu, Shi-Rong; Qin, Chao-Jian; Lü, Quan; Xu, Li

    2011-04-01

    A new conception of nano-laser is proposed in which depending on the size of nano-clusters (silicon quantum dots (QD)), the pumping level of laser can be tuned by the quantum confinement (QC) effect, and the population inversion can be formed between the valence band and the localized states in gap produced from the surface bonds of nano-clusters. Here we report the experimental demonstration of nano-laser on silicon quantum dots fabricated by nanosecond pulse laser. The peaks of stimulated emission are observed at 605 nm and 693 nm. Through the micro-cavity of nano-laser, a full width at half maximum of the peak at 693 nm can reach to 0.5 nm. The theoretical model and the experimental results indicate that it is a necessary condition for setting up nano-laser that the smaller size of QD (d < 3 nm) can make the localized states into band gap. The emission energy of nano-laser will be limited in the range of 1.7-2.3 eV generally due to the position of the localized states in gap, which is in good agreement between the experiments and the theory.

  13. Dipole nano-laser: Theory and properties

    SciTech Connect

    Ghannam, T.

    2014-03-31

    In this paper we outline the main quantum properties of the system of nano-based laser called Dipole Nano-Laser emphasizing mainly on its ability to produce coherent light and for different configurations such as different embedding materials and subjecting it to an external classical electric field.

  14. Room-temperature near-infrared high-Q perovskite whispering-gallery planar nanolasers.

    PubMed

    Zhang, Qing; Ha, Son Tung; Liu, Xinfeng; Sum, Tze Chien; Xiong, Qihua

    2014-10-08

    Near-infrared (NIR) solid-state micro/nanolasers are important building blocks for true integration of optoelectronic circuitry. Although significant progress has been made in III-V nanowire lasers with achieving NIR lasing at room temperature, challenges remain including low quantum efficiencies and high Auger losses. Importantly, the obstacles toward integrating one-dimensional nanowires on the planar ubiquitous Si platform need to be effectively tackled. Here we demonstrate a new family of planar room-temperature NIR nanolasers based on organic-inorganic perovskite CH3NH3PbI(3-a)X(a) (X = I, Br, Cl) nanoplatelets. Their large exciton binding energies, long diffusion lengths, and naturally formed high-quality planar whispering-gallery mode cavities ensure adequate gain and efficient optical feedback for low-threshold optically pumped in-plane lasing. We show that these remarkable wavelength tunable whispering-gallery nanolasers can be easily integrated onto conductive platforms (Si, Au, indium tin oxide, and so forth). Our findings open up a new class of wavelength tunable planar nanomaterials potentially suitable for on-chip integration.

  15. Semiconductor plasmonic nanolasers: current status and perspectives

    NASA Astrophysics Data System (ADS)

    Gwo, Shangjr; Shih, Chih-Kang

    2016-08-01

    Scaling down semiconductor lasers in all three dimensions holds the key to the development of compact, low-threshold, and ultrafast coherent light sources, as well as integrated optoelectronic and plasmonic circuits. However, the minimum size of conventional semiconductor lasers utilizing dielectric cavity resonators (photonic cavities) is limited by the diffraction limit. To date, surface plasmon amplification by stimulated emission of radiation (spaser)-based plasmonic nanolaser is the only photon and plasmon-emitting device capable of this remarkable feat. Specifically, it has been experimentally demonstrated that the use of plasmonic cavities based on metal-insulator-semiconductor (MIS) nanostructures can indeed break the diffraction limit in all three dimensions. In this review, we present an updated overview of the current status for plasmonic nanolasers using the MIS configuration and other related metal-cladded semiconductor microlasers. In particular, by using composition-varied indium gallium nitride/gallium nitride core-shell nanorods, it is possible to realize all-color, single-mode nanolasers in the full visible wavelength range with ultralow continuous-wave (CW) lasing thresholds. The lasing action in these subdiffraction plasmonic cavities is achieved via a unique auto-tuning mechanism based on the property of weak size dependence inherent in plasmonic nanolasers. As for the choice of metals in the plasmonic structures, epitaxial silver films and giant colloidal silver crystals have been shown to be the superior constituent materials for plasmonic cavities due to their low plasmonic losses in the visible and near-infrared (NIR) spectral regions. In this review, we also provide some perspectives on the challenges and opportunities in this exciting new research frontier.

  16. Lunar base heat pump

    NASA Technical Reports Server (NTRS)

    Goldman, Jeffrey H.; Tetreault, R.; Fischbach, D.; Walker, D.

    1994-01-01

    A heat pump is a device which elevates the temperature of a heat flow by a means of an energy input. By doing this, the heat pump can cause heat to transfer faster from a warm region to a cool region, or it can cause heat to flow from a cool region to a warmer region. The second case is the one which finds vast commercial applications such as air conditioning, heating, and refrigeration. Aerospace applications of heat pumps include both cases. The NASA Johnson Space Center is currently developing a Life Support Systems Integration Facility (LSSIF, previously SIRF) to provide system-level integration, operational test experience, and performance data that will enable NASA to develop flight-certified hardware for future planetary missions. A high lift heat pump is a significant part of the TCS hardware development associated with the LSSIF. The high lift heat pump program discussed here is being performed in three phases. In Phase 1, the objective is to develop heat pump concepts for a lunar base, a lunar lander, and for a ground development unit for the SIRF. In Phase 2, the design of the SIRF ground test unit is being performed, including identification and evaluation of safety and reliability issues. In Phase 3, the SIRF unit will be manufactured, tested, and delivered to the NASA Johnson Space Center.

  17. Lunar Base Heat Pump

    NASA Technical Reports Server (NTRS)

    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.

  18. Asymmetric mode scattering in strongly coupled photonic crystal nanolasers.

    PubMed

    Marconi, M; Javaloyes, J; Raineri, F; Levenson, J A; Yacomotti, A M

    2016-12-15

    We investigate the basic mechanism of nonlinear mode competition in two semiconductor-coupled nanocavities operating in the laser regime. For this, we study energy transfer between bonding (in-phase) and anti-bonding (out-of-phase) modes of the system formed by two strongly coupled photonic crystal nanolasers. We experimentally observe mode switching from the blue-detuned to the red-detuned mode as the pump power is increased. A semi-classical description in terms of mean-field equations allows us to explain this phenomenon as stimulated scattering due to carrier population oscillations in the cavities at the mode splitting frequency. We predict such asymmetrical mode interaction to be universal in arrays of optically coupled semiconductor micro and nanocavities.

  19. A high-resolution strain-gauge nanolaser

    PubMed Central

    Choi, Jae-Hyuck; No, You-Shin; So, Jae-Pil; Lee, Jung Min; Kim, Kyoung-Ho; Hwang, Min-Soo; Kwon, Soon-Hong; Park, Hong-Gyu

    2016-01-01

    Interest in mechanical compliance has been motivated by the development of flexible electronics and mechanosensors. In particular, studies and characterization of structural deformation at the fundamental scale can offer opportunities to improve the device sensitivity and spatiotemporal response; however, the development of precise measurement tools with the appropriate resolution remains a challenge. Here we report a flexible and stretchable photonic crystal nanolaser whose spectral and modal behaviours are sensitive to nanoscale structural alterations. Reversible spectral tuning of ∼26 nm in lasing wavelength, with a sub-nanometre resolution of less than ∼0.6 nm, is demonstrated in response to applied strain ranging from −10 to 12%. Instantaneous visualization of the sign of the strain is also characterized by exploring the structural and corresponding modal symmetry. Furthermore, our high-resolution strain-gauge nanolaser functions as a stable and deterministic strain-based pH sensor in an opto-fluidic system, which may be useful for further analysis of chemical/biological systems. PMID:27175544

  20. Quantum properties of light emitted by dipole nano-laser

    NASA Astrophysics Data System (ADS)

    Ghannam, Talal

    Recent technological advances allow entire optical systems to be lithographically implanted on small silicon chips. These systems include tiny semiconductor lasers that function as light sources for digital optical signals. Future advances will rely on even smaller components. At the theoretical limit of this process, the smallest lasers will have an active medium consisting of a single atom (natural or artificial). Several suggestions for how this can be accomplished have already been published, such as nano-lasers based on photonic crystals and nano wires. In particular, the "dipole nanolaser" consists of a single quantum dot functioning as the active medium. It is optically coupled to a metal nanoparticles that form a resonant cavity. Laser light is generated from the near-field optical signal. The proposed work is a theoretical exploration of the nature of the resulting laser light. The dynamics of the system will be studied and relevant time scales described. These will form the basis for a set of operator equations describing the quantum properties of the emitted light. The dynamics will be studied in both density matrix and quantum Langevin formulations, with attention directed to noise sources. The equations will be linearized and solved using standard techniques. The result of the study will be a set of predicted noise spectra describing the statistics of the emitted light. The goal will be to identify the major noise contributions and suggest methods for suppressing them. This will be done by studying the probability of getting squeezed light from the nanoparticle for the certain scheme of parameters.

  1. Array integration of thousands of photonic crystal nanolasers

    NASA Astrophysics Data System (ADS)

    Watanabe, Takumi; Abe, Hiroshi; Nishijima, Yoshiaki; Baba, Toshihiko

    2014-03-01

    Photonic crystal (PC) nanolasers often consist of air-bridge PC slab, which enhances optical confinement while limiting its size to 30 × 30 μm2 due to the mechanical fragileness. This limit is broken by resin-mediated bonding of the PC slab on a host substrate. In this paper, we demonstrate a GaInAsP PC slab with a size of over 100 × 100 μm2 in which 1089, 2376, and 11 664 nanolasers showing high-yield laser operation are integrated.

  2. Array integration of thousands of photonic crystal nanolasers

    SciTech Connect

    Watanabe, Takumi Abe, Hiroshi; Nishijima, Yoshiaki; Baba, Toshihiko

    2014-03-24

    Photonic crystal (PC) nanolasers often consist of air-bridge PC slab, which enhances optical confinement while limiting its size to 30 × 30 μm{sup 2} due to the mechanical fragileness. This limit is broken by resin-mediated bonding of the PC slab on a host substrate. In this paper, we demonstrate a GaInAsP PC slab with a size of over 100 × 100 μm{sup 2} in which 1089, 2376, and 11 664 nanolasers showing high-yield laser operation are integrated.

  3. Lunar base heat pump, phase 1 draft

    NASA Astrophysics Data System (ADS)

    Goldman, Jeffrey H.; Harvey, A.; Lovell, T.; Walker, David H.

    1994-04-01

    This report describes the Phase 1 process and analysis used to select a refrigerant and thermodynamic cycle as the basis of a vapor compression heat pump requiring a high temperature lift, then to perform a preliminary design to implement the selected concept, including major component selection. Use of a vapor compression heat pump versus other types was based on prior work performed for the Electric Power Research Institute. A high lift heat pump is needed to enable a thermal control system to remove heat down to 275K from a habitable volume when the external thermal environment is severe. For example, a long-term lunar base habitat will reject heat from a space radiator to a 325K environment. The first step in the selection process was to perform an optimization trade study, quantifying the effect of radiator operating temperature and heat pump efficiency on total system mass; then, select the radiator operating temperature corresponding to the lowest system mass. Total system mass included radiators, all heat pump components and the power supply system. The study showed that lunar night operation, with no temperature lift, dictated the radiator size. To operate otherwise would require a high mass penalty to store power. With the defined radiation surface, and heat pump performances assumed to be from 40 percent to 60 percent of the Carnot ideal, the optimum heat rejection temperature ranged from 387K to 377K, as a function of heat pump performance. Refrigerant and thermodynamic cycles were then selected to best meet the previously determined design conditions. The system was then adapted as a ground-based prototype lifting temperature to 360K (versus 385K for flight unit) and using readily available commercial-grade components. Over 40 refrigerants, separated into wet and dry compression behavioral types, were considered in the selection process. Refrigerants were initially screened for acceptable critical temperature. The acceptable refrigerants were analyzed

  4. Lunar base heat pump, phase 1

    NASA Astrophysics Data System (ADS)

    Goldman, Jeffrey H.; Harvey, A.; Lovell, T.; Walker, David H.

    1994-07-01

    This report describes the Phase 1 process and analysis used to select a refrigerant and thermodynamic cycle as the basis of a vapor compression heat pump requiring a high temperature lift, then to perform a preliminary design to implement the selected concept, including major component selection. Use of a vapor compression heat pump versus other types was based on prior work performed for the Electric Power Research Institute. A high lift heat pump is needed to enable a thermal control system to remove heat down to 275 K from a habitable volume when the external thermal environment is severe. For example, a long-term lunar base habitat will reject heat from a space radiator to a 325 K environment. The first step in the selection process was to perform an optimization trade study, quantifying the effect of radiator operating temperature and heat pump efficiency on total system mass; then, select the radiator operating temperature corresponding to the lowest system mass. Total system mass included radiators, all heat pump components, and the power supply system. The study showed that lunar night operation, with no temperature lift, dictated the radiator size. To operate otherwise would require a high mass penalty to store power. With the defined radiation surface, and heat pump performances assumed to be from 40 percent to 60 percent of the Carnot ideal, the optimum heat rejection temperature ranged from 387 K to 377 K, as a function of heat pump performance. Refrigerant and thermodynamic cycles were then selected to best meet the previously determined design conditions. The system was then adapted as a ground-based prototype lifting temperature to 360 K (versus 385 K for flight unit) and using readily available commercial-grade components. Over 40 refrigerants, separated into wet and dry compression behavioral types, were considered in the selection process. Refrigerants were initially screened for acceptable critical temperature. The acceptable refrigerants were

  5. Lunar base heat pump, phase 1

    NASA Technical Reports Server (NTRS)

    Goldman, Jeffrey H.; Harvey, A.; Lovell, T.; Walker, David H.

    1994-01-01

    This report describes the Phase 1 process and analysis used to select a refrigerant and thermodynamic cycle as the basis of a vapor compression heat pump requiring a high temperature lift, then to perform a preliminary design to implement the selected concept, including major component selection. Use of a vapor compression heat pump versus other types was based on prior work performed for the Electric Power Research Institute. A high lift heat pump is needed to enable a thermal control system to remove heat down to 275 K from a habitable volume when the external thermal environment is severe. For example, a long-term lunar base habitat will reject heat from a space radiator to a 325 K environment. The first step in the selection process was to perform an optimization trade study, quantifying the effect of radiator operating temperature and heat pump efficiency on total system mass; then, select the radiator operating temperature corresponding to the lowest system mass. Total system mass included radiators, all heat pump components, and the power supply system. The study showed that lunar night operation, with no temperature lift, dictated the radiator size. To operate otherwise would require a high mass penalty to store power. With the defined radiation surface, and heat pump performances assumed to be from 40 percent to 60 percent of the Carnot ideal, the optimum heat rejection temperature ranged from 387 K to 377 K, as a function of heat pump performance. Refrigerant and thermodynamic cycles were then selected to best meet the previously determined design conditions. The system was then adapted as a ground-based prototype lifting temperature to 360 K (versus 385 K for flight unit) and using readily available commercial-grade components. Over 40 refrigerants, separated into wet and dry compression behavioral types, were considered in the selection process. Refrigerants were initially screened for acceptable critical temperature. The acceptable refrigerants were

  6. Quantum Efficiency of ZnO Nanowire Nanolasers

    SciTech Connect

    Zhang, Yanfeng; Russo, Richard E.; Mao, Samuel S.

    2005-03-28

    Crystalline ZnO nanowires were grown on sapphire and silicon substrates using pulsed-laser deposition. The optical properties of nanowire nanolasers, including their absolute light emission intensity and external and internal quantum efficiencies were experimentally determined. The external differential quantum efficiency was measured to be as high as 60% for lasing ZnO nanowires of 7.5 {micro}m in length, compared to a value of approximately 10% for photoluminescence. The absolute light emission intensity for individual nanowires was found to be in the vicinity of 0.1 mW. By measuring the dependence of external differential quantum efficiency on the cavity length, the internal quantum efficiency of ZnO nanowire nanolasers was determined to be about 85%.

  7. Cavity-free plasmonic nanolasing enabled by dispersionless stopped light

    PubMed Central

    Pickering, Tim; Hamm, Joachim M.; Page, A. Freddie; Wuestner, Sebastian; Hess, Ortwin

    2014-01-01

    When light is brought to a standstill, its interaction with gain media increases dramatically due to a singularity in the density of optical states. Concurrently, stopped light engenders an inherent and cavity-free feedback mechanism, similar in effect to the feedback that has been demonstrated and exploited in large-scale disordered media and random lasers. Here we study the spatial, temporal and spectral signatures of lasing in planar gain-enhanced nanoplasmonic structures at near-infrared frequencies and show that the stopped-light feedback mechanism allows for nanolasing without a cavity. We reveal that in the absence of cavity-induced feedback, the subwavelength lasing mode forms dynamically as a phase-locked superposition of quasi dispersion-free waveguide modes. This mechanism proves remarkably robust against interface roughness and offers a new route towards nanolasing, the experimental realization of ultra-thin surface emitting lasers, and cavity-free active quantum plasmonics. PMID:25230337

  8. Which breast pump for which mother: an evidence-based approach to individualizing breast pump technology.

    PubMed

    Meier, P P; Patel, A L; Hoban, R; Engstrom, J L

    2016-07-01

    The majority of new mothers in the United States use breast pumps in the first 4 months postbirth in order to achieve their personal human milk feeding goals. Although these mothers seek guidance from health-care professionals with respect to the type and use of breast pumps, there are few evidence-based guidelines to guide this professional advice. This paper reviews the evidence to facilitate professional individualization of breast pump recommendations using three categories of literature: the infant as the gold standard to which the pump is compared; the degree of maternal breast pump dependency (for example, the extent to which the breast pump replaces the infant for milk removal and mammary gland stimulation); and the stage of lactation for which the pump replaces the infant. This review can also serve to inform public and private payers with respect to individualizing breast pump type to mother-infant dyad characteristics.

  9. Single-crystalline aluminum film for ultraviolet plasmonic nanolasers

    NASA Astrophysics Data System (ADS)

    Chou, Bo-Tsun; Chou, Yu-Hsun; Wu, Yen-Mo; Chung, Yi-Cheng; Hsueh, Wei-Jen; Lin, Shih-Wei; Lu, Tien-Chang; Lin, Tzy-Rong; Lin, Sheng-Di

    2016-01-01

    Significant advances have been made in the development of plasmonic devices in the past decade. Plasmonic nanolasers, which display interesting properties, have come to play an important role in biomedicine, chemical sensors, information technology, and optical integrated circuits. However, nanoscale plasmonic devices, particularly those operating in the ultraviolet regime, are extremely sensitive to the metal and interface quality. Thus, these factors have a significant bearing on the development of ultraviolet plasmonic devices. Here, by addressing these material-related issues, we demonstrate a low-threshold, high-characteristic-temperature metal-oxide-semiconductor ZnO nanolaser that operates at room temperature. The template for the ZnO nanowires consists of a flat single-crystalline Al film grown by molecular beam epitaxy and an ultrasmooth Al2O3 spacer layer synthesized by atomic layer deposition. By effectively reducing the surface plasmon scattering and metal intrinsic absorption losses, the high-quality metal film and the sharp interfaces formed between the layers boost the device performance. This work should pave the way for the use of ultraviolet plasmonic nanolasers and related devices in a wider range of applications.

  10. Single-crystalline aluminum film for ultraviolet plasmonic nanolasers

    PubMed Central

    Chou, Bo-Tsun; Chou, Yu-Hsun; Wu, Yen-Mo; Chung, Yi-Cheng; Hsueh, Wei-Jen; Lin, Shih-Wei; Lu, Tien-Chang; Lin, Tzy-Rong; Lin, Sheng-Di

    2016-01-01

    Significant advances have been made in the development of plasmonic devices in the past decade. Plasmonic nanolasers, which display interesting properties, have come to play an important role in biomedicine, chemical sensors, information technology, and optical integrated circuits. However, nanoscale plasmonic devices, particularly those operating in the ultraviolet regime, are extremely sensitive to the metal and interface quality. Thus, these factors have a significant bearing on the development of ultraviolet plasmonic devices. Here, by addressing these material-related issues, we demonstrate a low-threshold, high-characteristic-temperature metal-oxide-semiconductor ZnO nanolaser that operates at room temperature. The template for the ZnO nanowires consists of a flat single-crystalline Al film grown by molecular beam epitaxy and an ultrasmooth Al2O3 spacer layer synthesized by atomic layer deposition. By effectively reducing the surface plasmon scattering and metal intrinsic absorption losses, the high-quality metal film and the sharp interfaces formed between the layers boost the device performance. This work should pave the way for the use of ultraviolet plasmonic nanolasers and related devices in a wider range of applications. PMID:26814581

  11. Detection of endotoxin using a photonic crystal nanolaser

    NASA Astrophysics Data System (ADS)

    Takahashi, Daichi; Hachuda, Shoji; Watanabe, Takumi; Nishijima, Yoshiaki; Baba, Toshihiko

    2015-03-01

    Fast and reliable detection of endotoxin (ET) in medical equipment and pharmaceutical products is an essential precursor to clinical treatment. In this study, we demonstrate the use of shifts in wavelength of photonic crystal nanolasers for sensing the Limulus amebocyte lysate reaction, which is a standard method for detecting ET. From working curves of wavelength shift vs ET concentration, whose correlation factors were as high as 98%, we detected a required concentration of 0.001 EU/ml within 33 min and detected a low concentration of 0.0001 EU/ml.

  12. Detection of endotoxin using a photonic crystal nanolaser

    SciTech Connect

    Takahashi, Daichi; Hachuda, Shoji; Watanabe, Takumi; Nishijima, Yoshiaki; Baba, Toshihiko

    2015-03-30

    Fast and reliable detection of endotoxin (ET) in medical equipment and pharmaceutical products is an essential precursor to clinical treatment. In this study, we demonstrate the use of shifts in wavelength of photonic crystal nanolasers for sensing the Limulus amebocyte lysate reaction, which is a standard method for detecting ET. From working curves of wavelength shift vs ET concentration, whose correlation factors were as high as 98%, we detected a required concentration of 0.001 EU/ml within 33 min and detected a low concentration of 0.0001 EU/ml.

  13. A handy liquid metal based electroosmotic flow pump.

    PubMed

    Gao, Meng; Gui, Lin

    2014-06-07

    A room temperature liquid metal based electroosmotic flow (EOF) pump has been proposed in this work. This low-cost EOF pump is convenient for both fabrication and integration. It utilizes polydimethylsiloxane (PDMS) microchannels filled with the liquid-metal as non-contact pump electrodes. The electrode channels are fabricated symmetrically to both sides of the pumping channel, having no contact with the pumping channel. To test the pumping performance of the EOF pump, the mean flow velocities of the fluid (DI water) in the EOF pumps were experimentally measured by tracing the fluorescent microparticles in the flow. To provide guidance for designing a low voltage EOF pump, parametric studies on dimensions of the electrode and pumping channels were performed in this work. According to the experimental results, the pumping speed can reach 5.93 μm s(-1) at a driving voltage of only 1.6 V, when the gap between the electrode and the pumping channel is 20 μm. Injecting a room temperature liquid metal into microchannels can provide a simple, rapid, low-cost but accurately self-aligned way to fabricate microelectrodes for EOF pumps, which is a promising method to achieve the miniaturization and integration of the EOF pump in microfluidic systems. The non-contact liquid electrodes have no influence on the fluid in the pumping channel when pumping, reducing Joule heat generation and preventing gas bubble formation at the surface of electrodes. The pump has great potential to drive a wide range of fluids, such as drug reagents, cell suspensions and biological macromolecule solutions.

  14. Pump

    SciTech Connect

    Johnson, J.W.; Abdul.Hye, A.B.M.

    1983-10-25

    A pump for injecting chemicals into a well employs a pivot arm for synchronous movement with a well pump. The pivot arm causes reciprocation of a plunger within the body of the chemical pump. The plunger, during its upward stroke causes the entry of chemicals from an outside source into the pump body and, during its downward stroke, causes the exiting of the chemicals into the well. (2 claims.

  15. Pump hump characteristic research based on mass transfer equation

    NASA Astrophysics Data System (ADS)

    Liu, D. M.; Zhao, Y. Z.; Liu, X. B.; Ma, Y.; Wang, W. F.

    2015-01-01

    The current development of modern pumped storage plants aims towards a higher flexibility in operation, an extended operation range of the hydraulic machine (especially in the pumping mode), and a higher reliability. The pumping requirements are the crucial design drivers, since, even if the turbine mode performance is very sound, the success of a project depends also on the pump turbine delivering the required maximum pump head and starting reliably in pump mode. Pump hump (pump instability working points at highest head) which is an instability source to the pump-turbine vibration is a serious damage to the pump operation on high head. So the pump hump and cavitation number based on the numerical simulation and experiment results are shown in this paper. The pump hump is sensitive affected by the cavitation number. With the cavitation number decreasing, the hump on flow characteristic curve (e.g. head-flow rate curve, H-Q curve) is gradually decreasing until vanished. Predicting cavitating flows with multi-phase CFD computations is still a very challenging task. Some results of ongoing work in this field are presented. The hump on H-Q curve with cavitation number is discussed in this paper.

  16. Comparison of two arthroscopic pump systems based on image quality.

    PubMed

    Tuijthof, G J M; van den Boomen, H; van Heerwaarden, R J; van Dijk, C N

    2008-06-01

    The effectiveness of arthroscopic pump systems has been investigated with either subjective measures or measures that were unrelated to the image quality. The goal of this study is to determine the performance of an automated pump in comparison to a gravity pump based on objective assessment of the quality of the arthroscopic view. Ten arthroscopic operations performed with a gravity pump and ten performed with an automated pump (FMS Duo system) were matched on duration of the surgery and shaver usage, type of operation, and surgical experience. Quality of the view was defined by means of the presence or absence of previously described definitions of disturbances (bleeding, turbidity, air bubbles, and loose fibrous tissue). The percentage of disturbances for all operations was assessed with a time-disturbance analysis of the recorded operations. The Mann-Whitney U test shows a significant difference in favor of the automated pump for the presence of turbidity only (Exact Sig. [2*(1-tailed Sig.)] = 0.015). Otherwise, no differences were determined (Exact Sig. [2*(1-tailed Sig.)] > 0.436). A new objective method is successfully applied to assess efficiency of pump systems based on the quality of the arthroscopic view. Important disturbances (bleeding, air bubbles, and loose fibrous tissue) are not reduced by an automated pump used in combination with a tourniquet. The most frequent disturbance turbidity is reduced by around 50%. It is questionable if this result justifies the use of an automated pump for straightforward arthroscopic knee surgeries using a tourniquet.

  17. PUMPS

    DOEpatents

    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.

  18. 71. Detail view of water pump at base of water ...

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

    71. Detail view of water pump at base of water tank with wall of blowing engine house in background. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  19. Ultrafast nanolaser device for detecting cancer in a single live cell.

    SciTech Connect

    Gourley, Paul Lee; McDonald, Anthony Eugene

    2007-11-01

    Emerging BioMicroNanotechnologies have the potential to provide accurate, realtime, high throughput screening of live tumor cells without invasive chemical reagents when coupled with ultrafast laser methods. These optically based methods are critical to advancing early detection, diagnosis, and treatment of disease. The first year goals of this project are to develop a laser-based imaging system integrated with an in- vitro, live-cell, micro-culture to study mammalian cells under controlled conditions. In the second year, the system will be used to elucidate the morphology and distribution of mitochondria in the normal cell respiration state and in the disease state for normal and disease states of the cell. In this work we designed and built an in-vitro, live-cell culture microsystem to study mammalian cells under controlled conditions of pH, temp, CO2, Ox, humidity, on engineered material surfaces. We demonstrated viability of cell culture in the microsystem by showing that cells retain healthy growth rates, exhibit normal morphology, and grow to confluence without blebbing or other adverse influences of the material surfaces. We also demonstrated the feasibility of integrating the culture microsystem with laser-imaging and performed nanolaser flow spectrocytometry to carry out analysis of the cells isolated mitochondria.

  20. Polypyrrole-Based Implantable Electroactive Pump for Controlled Drug Microinjection.

    PubMed

    Yan, Bingxi; Li, Boyi; Kunecke, Forest; Gu, Zhen; Guo, Liang

    2015-07-15

    Implantable devices for long-lasting controlled insulin microinjection are of great value to diabetic patients. To address this need, we develop a flexible electroactive pump based on a biocompatible polypyrrole composite film that comprises a polypyrrole matrix and a macromolecular dopant of polycaprolactone-block-polytetrahydrofuran-block-polycaprolactone. Using phosphate-buffered saline as the electrolyte, this film demonstrates much higher electroactivity and reproducibility than conventional Cl--doped polypyrrole, making it an excellent actuator for driving an implantable pump. At a driving current density of 1 mA/cm2, the pump demonstrates a consistent output capacity of 10.5 at 0.35 μL/s over 20 cycles. This work paves the way for the development of an implantable electroactive pump to improve the quality of life of diabetics.

  1. The numerical simulation based on CFD of hydraulic turbine pump

    NASA Astrophysics Data System (ADS)

    Duan, X. H.; Kong, F. Y.; Liu, Y. Y.; Zhao, R. J.; Hu, Q. L.

    2016-05-01

    As the functions of hydraulic turbine pump including self-adjusting and compensation with each other, it is far-reaching to analyze its internal flow by the numerical simulation based on CFD, mainly including the pressure field and the velocity field in hydraulic turbine and pump.The three-dimensional models of hydraulic turbine pump are made by Pro/Engineer software;the internal flow fields in hydraulic turbine and pump are simulated numerically by CFX ANSYS software. According to the results of the numerical simulation in design condition, the pressure field and the velocity field in hydraulic turbine and pump are analyzed respectively .The findings show that the static pressure decreases systematically and the pressure gradient is obvious in flow area of hydraulic turbine; the static pressure increases gradually in pump. The flow trace is regular in suction chamber and flume without spiral trace. However, there are irregular traces in the turbine runner channels which contrary to that in flow area of impeller. Most of traces in the flow area of draft tube are spiral.

  2. Peristaltic pump-based low range pressure sensor calibration system

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  3. Peristaltic pump-based low range pressure sensor calibration system

    SciTech Connect

    Vinayakumar, K. B.; Naveen Kumar, G.; Rajanna, K. E-mail: krajanna2011@gmail.com; Nayak, M. M.; Dinesh, N. S.

    2015-11-15

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

  4. Peristaltic pump-based low range pressure sensor calibration system.

    PubMed

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

    2015-11-01

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

  5. Optimization of centrifugal pump cavitation performance based on CFD

    NASA Astrophysics Data System (ADS)

    Xie, S. F.; Wang, Y.; Liu, Z. C.; Zhu, Z. T.; Ning, C.; Zhao, L. F.

    2015-01-01

    In order to further improve the cavitation performance of a centrifugal pump, slots on impeller blade near inlet were studied and six groups of hydraulic model were designed. Base on cavitating flow feature inside a centrifugal pump, bubble growth and implosion are calculated from the Rayleigh-Plesset equation which describes the dynamic behavior of spherical bubble and RNG κ-epsilon model was employed to simulate and analyze the internal two-phase flow of the model pump under the same conditions. The simulation results show that slots on blade near inlet could improve the cavitation performance and cavitation performance improvement of the second group was more obvious. Under the same conditions, the pressure on the back of blade near inlet was higher than the pressure on the back of unmodified blade near inlet, and energy distribution in the flow channel between the two blades was more uniform with a small change of head.

  6. Centrifugal Force Based Magnetic Micro-Pump Driven by Rotating Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Kim, S. H.; Hashi, S.; Ishiyama, K.

    2011-01-01

    This paper presents a centrifugal force based magnetic micro-pump for the pumping of blood. Most blood pumps are driven by an electrical motor with wired control. To develop a wireless and battery-free blood pump, the proposed pump is controlled by external rotating magnetic fields with a synchronized impeller. Synchronization occurs because the rotor is divided into multi-stage impeller parts and NdFeB permanent magnet. Finally, liquid is discharged by the centrifugal force of multi-stage impeller. The proposed pump length is 30 mm long and19 mm in diameter which much smaller than currently pumps; however, its pumping ability satisfies the requirement for a blood pump. The maximum pressure is 120 mmHg and the maximum flow rate is 5000ml/min at 100 Hz. The advantage of the proposed pump is that the general mechanical problems of a normal blood pump are eliminated by the proposed driving mechanism.

  7. Retinal-Based Proton Pumping in the Near Infrared.

    PubMed

    Ganapathy, Srividya; Venselaar, Hanka; Chen, Que; de Groot, Huub J M; Hellingwerf, Klaas J; de Grip, Willem J

    2017-02-15

    Proteorhodopsin (PR) and Gloeobacter rhodopsin (GR) are retinal-based light-driven proton pumps that absorb visible light (maxima at 520-540 nm). Shifting the action spectra of these proton pumps beyond 700 nm would generate new prospects in optogenetics, membrane sensor technology, and complementation of oxygenic phototrophy. We therefore investigated the effect of red-shifting analogues of retinal, combined with red-shifting mutations, on the spectral properties and pump activity of the resulting pigments. We investigated a variety of analogues, including many novel ones. One of the novel analogues we tested, 3-methylamino-16-nor-1,2,3,4-didehydroretinal (MMAR), produced exciting results. This analogue red-shifted all of the rhodopsin variants tested, accompanied by a strong broadening of the absorbance band, tailing out to 850-950 nm. In particular, MMAR showed a strong synergistic effect with the PR-D212N,F234S double mutant, inducing an astonishing 200 nm red shift in the absorbance maximum. To our knowledge, this is by far the largest red shift reported for any retinal protein. Very importantly, all MMAR-containing holoproteins are the first rhodopsins retaining significant pump activity under near-infrared illumination (730 nm light-emitting diode). Such MMAR-based rhodopsin variants present very promising opportunities for further synthetic biology modification and for a variety of biotechnological and biophysical applications.

  8. Retinal-Based Proton Pumping in the Near Infrared

    PubMed Central

    2017-01-01

    Proteorhodopsin (PR) and Gloeobacter rhodopsin (GR) are retinal-based light-driven proton pumps that absorb visible light (maxima at 520–540 nm). Shifting the action spectra of these proton pumps beyond 700 nm would generate new prospects in optogenetics, membrane sensor technology, and complementation of oxygenic phototrophy. We therefore investigated the effect of red-shifting analogues of retinal, combined with red-shifting mutations, on the spectral properties and pump activity of the resulting pigments. We investigated a variety of analogues, including many novel ones. One of the novel analogues we tested, 3-methylamino-16-nor-1,2,3,4-didehydroretinal (MMAR), produced exciting results. This analogue red-shifted all of the rhodopsin variants tested, accompanied by a strong broadening of the absorbance band, tailing out to 850–950 nm. In particular, MMAR showed a strong synergistic effect with the PR-D212N,F234S double mutant, inducing an astonishing 200 nm red shift in the absorbance maximum. To our knowledge, this is by far the largest red shift reported for any retinal protein. Very importantly, all MMAR-containing holoproteins are the first rhodopsins retaining significant pump activity under near-infrared illumination (730 nm light-emitting diode). Such MMAR-based rhodopsin variants present very promising opportunities for further synthetic biology modification and for a variety of biotechnological and biophysical applications. PMID:28094925

  9. A Physically Based Model for Air-Lift Pumping

    NASA Astrophysics Data System (ADS)

    FrançOis, Odile; Gilmore, Tyler; Pinto, Michael J.; Gorelick, Steven M.

    1996-08-01

    A predictive, physically based model for pumping water from a well using air injection (air-lift pumping) was developed for the range of flow rates that we explored in a series of laboratory experiments. The goal was to determine the air flow rate required to pump a specific flow rate of water in a given well, designed for in-well air stripping of volatile organic compounds from an aquifer. The model was validated against original laboratory data as well as data from the literature. A laboratory air-lift system was constructed that consisted of a 70-foot-long (21-m-long) pipe, 5.5 inches (14 cm) inside diameter, in which an air line of 1.3 inches (3.3 cm) outside diameter was placed with its bottom at different elevations above the base of the long pipe. Experiments were conducted for different levels of submergence, with water-pumping rates ranging from 5 to 70 gallons/min (0.32-4.4 L/s), and air flow ranging from 7 to 38 standard cubic feet/min (0.2-1.1 m3 STP/min). The theoretical approach adopted in the model was based on an analysis of the system as a one-dimensional two-phase flow problem. The expression for the pressure gradient includes inertial energy terms, friction, and gas expansion versus elevation. Data analysis revealed that application of the usual drift-flux model to estimate the air void fraction is not adequate for the observed flow patterns: either slug or churn flow. We propose a modified drift-flux model that accurately predicts air-lift pumping requirements for a range of conditions representative of in-well air-stripping operations.

  10. Digital background calibration of charge pump based pipelined ADC

    NASA Astrophysics Data System (ADS)

    Singh, Anil; Agarwal, Alpana

    2016-11-01

    In the presented work, digital background calibration of a charge pump based pipelined ADC is presented. A 10-bit 100 MS/s pipelined ADC is designed using TSMC 0.18 µm CMOS technology operating on a 1.8 V power supply voltage. A power efficient opamp-less charge pump based technique is chosen to achieve the desired stage voltage gain of 2 and digital background calibration is used to calibrate the inter-stage gain error. After calibration, the ADC achieves an SNDR of 66.78 dB and SFDR of 79.3 dB. Also, DNL improves to +0.6/-0.4 LSB and INL improves from +9.3/-9.6 LSB to within ±0.5 LSB, consuming 16.53 mW of power.

  11. Super-sensitivity in label-free protein sensing using a nanoslot nanolaser.

    PubMed

    Kita, Shota; Hachuda, Shoji; Otsuka, Shota; Endo, Tatsuro; Imai, Yasunori; Nishijima, Yoshiaki; Misawa, Hiroaki; Baba, Toshihiko

    2011-08-29

    Microphotonic sensors have been actively studied with increasing demands for label-free biosensing in medical diagnoses and life sciences. For high-throughput and low-cost sensing, a high sensitivity is crucial for eliminating the pre-concentration process, while a simple setup of sensors is also desirable. This paper demonstrates a super-sensitivity for protein, which satisfies these requirements. The key device is a photonic crystal nanolaser, in particular with a nanoslot. Even using a simple setup, the nanolaser achieves an extraordinary-low detection limit for BSA protein, i.e. 255 fM on an average, which cannot be explained by its bulk index sensitivity. The specific adsorption of the protein is observed only around the nanoslot with strong laser intensity. This suggests that the super-sensitivity arises from the effective trapping of protein in the nanoslot.

  12. Pipe flow of pumping wet shotcrete based on lubrication layer.

    PubMed

    Chen, Lianjun; Liu, Guoming; Cheng, Weimin; Pan, Gang

    2016-01-01

    Wet shotcrete can reduce dust and improve supporting strength, however, safe and efficient pipage is a key technical part of wet shotcrete process. The paper studied the pipe flow law of wet shotcrete based on lubrication layer by build the experimental pumping circuit of wet shotcrete that can carry out a number of full-scale pumping tests. The experimental results show there was a linear relationship between pressure loss and flow rate. Combined with the Buckingham rheological equation, the computing equations of the yield shear stress and plastic viscosity were deduced through linear regression. A simple analytical method allowing for a rough estimation of the pumping pressure was proposed and used when considering the lubrication layer of wet shotcrete in pipes. In addition, two kinds of particulate distributive models were established along the time axial to analyze the formation of lubrication layer which is related with particles migration. By computational fluid dynamics simulation, the lubrication layer thickness of different mix proportions was estimated. A new method for measuring the thickness of lubrication layer was proposed to verify it by binarization processing. Finally, according to the comparative analysis of experiments, simulation and computed value, it can be seen that the lubrication layer plays a key role in the process of wet shotcrete flow and with the increase of lubrication layer thickness pipe pressure declines gradually.

  13. Magnetic plasmonic metamaterials in actively pumped host medium and plasmonic nanolaser

    NASA Astrophysics Data System (ADS)

    Sarychev, Andrey K.; Tartakovsky, Gennady

    2006-08-01

    We consider plasmonic nanoantennas immersed in active host medium. Specifically shaped metal nanoantennas can exhibit strong magnetic properties in the optical spectral range due to the excitation of Magnetic Resonance Plasmons (MRP). A case when a metamaterial comprising such nanoantennas can demonstrate both "left-handiness" and negative permeability in the optical range is considered. We show that high losses predicted for optical "left-handed" materials can be compensated in the gain medium. Gains required to achieve local generation in such magnetic active metamaterials are calculated for real metals

  14. Accuracy of a New Patch Pump Based on a Microelectromechanical System (MEMS) Compared to Other Commercially Available Insulin Pumps

    PubMed Central

    Borot, Sophie; Franc, Sylvia; Cristante, Justine; Penfornis, Alfred; Benhamou, Pierre-Yves; Guerci, Bruno; Hanaire, Hélène; Renard, Eric; Reznik, Yves; Simon, Chantal

    2014-01-01

    The JewelPUMP™ (JP) is a new patch pump based on a microelectromechanical system that operates without any plunger. The study aimed to evaluate the infusion accuracy of the JP in vitro and in vivo. For the in vitro studies, commercially available pumps meeting the ISO standard were compared to the JP: the MiniMed® Paradigm® 712 (MP), Accu-Chek® Combo (AC), OmniPod® (OP), Animas® Vibe™ (AN). Pump accuracy was measured over 24 hours using a continuous microweighing method, at 0.1 and 1 IU/h basal rates. The occlusion alarm threshold was measured after a catheter occlusion. The JP, filled with physiological serum, was then tested in 13 patients with type 1 diabetes simultaneously with their own pump for 2 days. The weight difference was used to calculate the infused insulin volume. The JP showed reduced absolute median error rate in vitro over a 15-minute observation window compared to other pumps (1 IU/h): ±1.02% (JP) vs ±1.60% (AN), ±1.66% (AC), ±2.22% (MP), and ±4.63% (OP), P < .0001. But there was no difference over 24 hours. At 0.5 IU/h, the JP was able to detect an occlusion earlier than other pumps: 21 (19; 25) minutes vs 90 (85; 95), 58 (42; 74), and 143 (132; 218) minutes (AN, AC, MP), P < .05 vs AN and MP. In patients, the 24-hour flow error was not significantly different between the JP and usual pumps (–2.2 ± 5.6% vs –0.37 ± 4.0%, P = .25). The JP was found to be easier to wear than conventional pumps. The JP is more precise over a short time period, more sensitive to catheter occlusion, well accepted by patients, and consequently, of potential interest for a closed-loop insulin delivery system. PMID:25079676

  15. Perspectives of Increasing Efficiency and Productivity of Electromagnetic Induction Pumps for Mercury Basing on Permanent Magnets

    SciTech Connect

    Bucenieks, I.

    2006-07-01

    In the next generation neutron sources the HLM (heavy liquid metals) such as lead, lead based eutectic alloys and mercury will be used both as spallation target material and simultaneously as the cooling liquid. In this aspect the design of safe and effective pumps for HLM recirculation at high pressure heads and big flow rates becomes important. For this purpose electromagnetic inductions pumps having no problems of hydraulic seals being in contact with liquid metal (electromagnetic forces in the liquid metal are induced by magnetic system located outside of the channel of pump) are more perspective from the point of view of their safety for operation at high temperature and radiation conditions in comparison with mechanical pumps. At the Institute of Physics of University of Latvia (IPUL) the design concept of electromagnetic induction pumps basing on the principle of rotating permanent magnets (PMP) have been developed. Such design concept of electromagnetic induction pumps has many advantages in comparison with traditionally used electromagnetic induction pumps basing on 3-phase linear flat or cylindrical inductors. The estimations of parameters of powerful pumps (such as overall dimensions of the active magnetic system, power of motor needed for pump drive, the efficiency of pump) for mercury for the developed by pump pressure heads in the range up to 10.0 bar and provided flow rates in the range up to 20 litres per second are demonstrated. (author)

  16. Sensitive and selective detection of prostate-specific antigen using a photonic crystal nanolaser.

    PubMed

    Hachuda, Shoji; Watanabe, Takumi; Takahashi, Daichi; Baba, Toshihiko

    2016-06-13

    The detection of low-concentration biomarkers is expected to facilitate the early diagnosis of severe diseases, including malignant tumors. Using photonic crystal nanolaser sensors, we detected prostate-specific antigen (PSA) from a concentration of 1 fM, which is difficult to detect by conventional enzyme-linked immunosorbent assay. The signal intensity and stability were improved by using a surfactant (i.e., ethanolamine). Even when a contaminant such as bovine serum albumin was mixed into the PSA sample, thereby increasing the concentration of the contaminant ten billion times, it was still possible to maintain a high level of detection.

  17. GaAs-based high temperature electrically pumped polariton laser

    SciTech Connect

    Baten, Md Zunaid; Bhattacharya, Pallab Frost, Thomas; Deshpande, Saniya; Das, Ayan; Lubyshev, Dimitri; Fastenau, Joel M.; Liu, Amy W. K.

    2014-06-09

    Strong coupling effects and polariton lasing are observed at 155 K with an edge-emitting GaAs-based microcavity diode with a single Al{sub 0.31}Ga{sub 0.69}As/Al{sub 0.41}Ga{sub 0.59}As quantum well as the emitter. The threshold for polariton lasing is observed at 90 A/cm{sup 2}, accompanied by a reduction of the emission linewidth to 0.85 meV and a blueshift of the emission wavelength by 0.89 meV. Polariton lasing is confirmed by the observation of a polariton population redistribution in momentum space and spatial coherence. Conventional photon lasing is recorded in the same device at higher pump powers.

  18. A nanomechanical device based on light-driven proton pumps.

    PubMed

    Ren, Quan; Zhao, Ya-Pu; Han, Li; Zhao, Hui-Bin

    2006-03-28

    In this paper, a hybrid device based on a microcantilever interfaced with bacteriorhodopsin (bR) is constructed. The microcantilever, on which the highly oriented bR film is self-assembled, undergoes controllable and reversible bending when the light-driven proton pump protein, bR, on the microcantilever surface is activated by visible light. Several control experiments are carried out to preclude the influence of heat and photothermal effects. It is shown that the nanomechanical motion is induced by the resulting gradient of protons, which are transported from the KCl solution on the cytoplasmic side of the bR film towards the extracellular side of the bR film. Along with a simple physical interpretation, the microfabricated cantilever interfaced with the organized molecular film of bR can simulate the natural machinery in converting solar energy to mechanical energy.

  19. Pump turbines. (Latest citations from Fluidex data base). Published Search

    SciTech Connect

    Not Available

    1992-05-01

    The bibliography contains citations concerning pump turbines with emphasis on pumped storage. Design, development, testing, operational evaluation, and problem areas are included. Many of the abstracts reference reports on flow characteristics, including draft tube surges, dynamic loads and forces vibration, cavitation, and starting problems. Both the pumping mode and the turbine (generating) mode, for analyses of speed rise, overpressure, overspeed, and general flow investigations are examined. (Contains 250 citations and includes a subject term index and title list.)

  20. Nanostructured carbon materials based electrothermal air pump actuators

    NASA Astrophysics Data System (ADS)

    Liu, Qing; Liu, Luqi; Kuang, Jun; Dai, Zhaohe; Han, Jinhua; Zhang, Zhong

    2014-05-01

    Actuator materials can directly convert different types of energy into mechanical energy. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid films as heating elements to transfer electrical stimulus into thermal energy, and finally convert it into mechanical energy. Both the actuation displacement and working temperature of the actuator films show the monotonically increasing trend with increasing driving voltage within the actuation process. Compared with common polymer nanocomposites based electrothermal actuators, our actuators exhibited better actuation performances with a low driving voltage (<10 V), large generated stress (tens of MPa), high gravimetric density (tens of J kg-1), and short response time (few hundreds of milliseconds). Besides that, the pump actuators exhibited excellent stability under cyclic actuation tests. Among these actuators, a relatively larger actuation strain was obtained for the r-GO film actuator due to the intrinsic gas-impermeability nature of graphene platelets. In addition, the high modulus of the r-GO and GO/SWCNT films also guaranteed the large generated stress and high work density. Specifically, the generated stress and gravimetric work density of the GO/SWCNT hybrid film actuator could reach up to more than 50 MPa and 30 J kg-1, respectively, under a driving voltage of 10 V. The resulting stress value is at least two orders of magnitude higher than that of natural muscles (~0.4 MPa).Actuator materials can directly convert different types of energy into mechanical energy. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid

  1. Nanolaser Spectroscopy of Genetically Engineered Yeast: New Tool for a Better Brew?

    NASA Astrophysics Data System (ADS)

    Gourley, Paul L.; Hendricks, Judy K.; Naviaux, Robert K.; Yaffe, Michael P.

    2006-03-01

    A basic function of the cell membrane is to selectively uptake ions or molecules from its environment to concentrate them into the interior. This concentration difference results in an osmostic pressure difference across the membrane. Ultimately, this pressure and its fluctuation from cell to cell will be limited by the availability and fluctuations of the solute concentrations in solution, the extent of inter-cell communication, and the state of respiring intracellular mitochondria that fuel the process. To measure these fluctuations, we have employed a high-speed nanolaser technique that samples the osmotic pressure in individual yeast cells and isolated mitochondria. We analyzed 2 yeast cell strains, normal baker’s yeast and a genetically-altered version, that differ only by the presence of mitochondrial DNA. The absence of mitochondrial DNA results in the complete loss of all the mtDNA-encoded proteins and RNAs, and loss of the pigmented, heme-containing cytochromes. These cells have mitochondria, but the mitochondria lack most normal respiratory chain complexes. The frequency distributions in the nanolaser spectra produced by wild-type and modified cells and mitochondria show a striking shift from Gaussian to Poissonian distributions, revealing a powerful novel method for studying statistical physics of yeast.

  2. Nanolaser spectroscopy of Normal and Genetically Defective Mitochondria: New Biostatistical Tool for Studying Disease

    NASA Astrophysics Data System (ADS)

    Gourley, Paul; Hendricks, Judy; Naviaux, Robert; Yaffe, Michael

    2007-03-01

    We report an analysis of wild and mutant strains of mitochondria from yeast cells using nanolaser spectroscopy to measure cytochrome density and its statistical variation in the population. The first strain 110 was derived from wild-type strain 104 (Saccharomyces cerevisiae) by removal of its mitochondrial DNA (mtDNA), resulting in loss of all mtDNA-encoded proteins and RNAs, and loss of the pigmented, heme-containing cytochromes a and b that can be detected in the laser spectra. Histograms of laser wavelengths produced by wild-type mitochondria produced peaked distributions, while mutant mitochondria exhibit asymmetric, highly skewed distributions. Surprisingly, all of these distributions exhibit extended tails and can be self-consistently fit with log-normal distribution functions. In striking contrast, the mitochondrial diameters (measured separately by microscopy) exhibit normal Gaussian distributions. These results indicate that the nanolaser spectra are useful for quantifying cytochrome content in mitochondria and may have important implications for quantifying defects in mitochondria that manifest human disease.

  3. Nanostructured carbon materials based electrothermal air pump actuators.

    PubMed

    Liu, Qing; Liu, Luqi; Kuang, Jun; Dai, Zhaohe; Han, Jinhua; Zhang, Zhong

    2014-06-21

    Actuator materials can directly convert different types of energy into mechanical energy. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid films as heating elements to transfer electrical stimulus into thermal energy, and finally convert it into mechanical energy. Both the actuation displacement and working temperature of the actuator films show the monotonically increasing trend with increasing driving voltage within the actuation process. Compared with common polymer nanocomposites based electrothermal actuators, our actuators exhibited better actuation performances with a low driving voltage (<10 V), large generated stress (tens of MPa), high gravimetric density (tens of J kg(-1)), and short response time (few hundreds of milliseconds). Besides that, the pump actuators exhibited excellent stability under cyclic actuation tests. Among these actuators, a relatively larger actuation strain was obtained for the r-GO film actuator due to the intrinsic gas-impermeability nature of graphene platelets. In addition, the high modulus of the r-GO and GO/SWCNT films also guaranteed the large generated stress and high work density. Specifically, the generated stress and gravimetric work density of the GO/SWCNT hybrid film actuator could reach up to more than 50 MPa and 30 J kg(-1), respectively, under a driving voltage of 10 V. The resulting stress value is at least two orders of magnitude higher than that of natural muscles (∼ 0.4 MPa).

  4. Diode-Laser Pumped Far-Infrared Local Oscillator Based on Semiconductor Quantum Wells

    NASA Technical Reports Server (NTRS)

    Kolokolov, K.; Li, J.; Ning, C. Z.; Larrabee, D. C.; Tang, J.; Khodaparast, G.; Kono, J.; Sasa, S.; Inoue, M.; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    The contents include: 1) Tetrahertz Field: A Technology Gap; 2) Existing THZ Sources and Shortcomings; 3) Applications of A THZ Laser; 4) Previous Optical Pumped LW Generations; 5) Optically Pumped Sb based Intersubband Generation Whys; 6) InGaAs/InP/AlAsSb QWs; 7) Raman Enhanced Optical Gain; 8) Pump Intensity Dependence of THZ Gain; 9) Pump-Probe Interaction Induced Raman Shift; 10) THZ Laser Gain in InGaAs/InP/AlAsSb QWs; 11) Diode-Laser Pumped Difference Frequency Generation (InGaAs/InP/AlAsSb QWs); 12) 6.1 Angstrom Semiconductor Quantum Wells; 13) InAs/GaSb/AlSb Nanostructures; 14) InAs/AlSb Double QWs: DFG Scheme; 15) Sb-Based Triple QWs: Laser Scheme; and 16) Exciton State Pumped THZ Generation. This paper is presented in viewgraph form.

  5. Control of centrifugal blood pump based on the motor current.

    PubMed

    Iijima, T; Inamoto, T; Nogawa, M; Takatani, S

    1997-07-01

    In this study, centrifugal pump performance was examined in a mock circulatory loop to derive an automatic pump rotational speed (rpm) control method. The pivot bearing supported sealless centrifugal pump was placed in the left ventricular apex to aorta bypass mode. The pneumatic pulsatile ventricle was used to simulate the natural ventricle. To simulate the suction effect in the ventricle, a collapsible rubber tube was placed in the inflow port of the centrifugal pump in series with the apex of the simulated ventricle. Experimentally, the centrifugal pump speed (rpm) was gradually increased to simulate the suction effect. The pump flow through the centrifugal pump measured by an electromagnetic flowmeter, the aortic pressure, and the motor current were continuously digitized at 100 Hz and stored in a personal computer. The analysis of the cross-spectral density between the pump flow and motor current waveforms revealed that 2 waveforms were highly correlated at the frequency range between 0 and 4 Hz, with the coherence and phase angles being close to 1.0 and 0 degree, respectively. The fast Fourier transform analysis of the motor current indicated that the second harmonic component of the motor current power density increased with the occurrence of the suction effect in the circuit. The ratio of the fundamental to the second harmonic component decreased less than 1.3 as the suction effect developed in the circuit. It is possible to detect and prevent the suction effect of the centrifugal blood pump in the natural ventricle through analysis of the motor current waveform.

  6. The analysis and system design for MCG measurement based on optically pumped cesium magnetometer

    NASA Astrophysics Data System (ADS)

    Yang, Zhang; Chong, Kang; Wang, Qingtao; Lei, Cheng; Zheng, Caiping

    2010-11-01

    At present, laser optical pumping magnetometer of sensitivity is continuous improved and can measure the range from Earth magnetic field to the bio-magnetic field. In the bio-magnetic field, magnetocardiography (MCG) is paid also more and more attention. In this paper, we will discuss cesium optically pumped magnetometer theoretical analysis, system design, the magnetic field gradient measuring principle. On this basis, we build optically pumped magnetometer in a gradient structure for the cardiac magnetic measurements and filter through the wavelet transform. Based on optical pumping magnetometer measuring MCG will be applied in life science, clinical medicine and other fields.

  7. Sol-Gel Based Polybenzimidazole Membranes for Hydrogen Pumping Devices

    SciTech Connect

    Benicewicz, Brian

    2014-02-26

    Electrochemical hydrogen pumping using a high temperature (>100°C) PBI membrane was demonstrated under non-humidified and humidified conditions at ambient pressures. Relatively low voltages were required to operate the pump over a wide range of hydrogen flow rates. The advantages of the high temperature capability were shown by operating the pump on reformate feed gas mixtures containing various amounts of CO and CO{sub 2}. Gas purity measurements on the cathode gas product were conducted and significant reductions in gas impurities were detected. The applicability of the PBI membrane for electrochemical hydrogen pumping and its durability under typical operating conditions was established with tests that lasted for nearly 4000 hours.

  8. Electromagnetic liquid pistons for capillarity-based pumping.

    PubMed

    Malouin, Bernard A; Vogel, Michael J; Olles, Joseph D; Cheng, Lili; Hirsa, Amir H

    2011-02-07

    The small scales associated with lab-on-a-chip technologies lend themselves well to capillarity-dominated phenomena. We demonstrate a new capillarity-dominated system where two adjoining ferrofluid droplets can behave as an electronically-controlled oscillator or switch by an appropriate balance of magnetic, capillary, and inertial forces. Their oscillatory motion can be exploited to displace a surrounding liquid (akin to an axial piston pump), forming electromagnetic "liquid pistons." Such ferrofluid pistons can pump a precise volume of liquid via finely tunable amplitudes (cf. pump stroke) or resonant frequencies (cf. pump speed) with no solid moving parts for long-term operation without wear in a small device. Furthermore, the rapid propagation of electromagnetic fields and the favorable scaling of capillary forces with size permit micron sized devices with very fast operating speeds (∼kHz). The pumping dynamics and performance of these liquid pistons is explored, with experimental measurements showing good agreement with a spherical cap model. While these liquid pistons may find numerous applications in micro- and mesoscale fluidic devices (e.g., remotely activated drug delivery), here we demonstrate the use of these liquid pistons in capillarity-dominated systems for chip-level, fast-acting adaptive liquid lenses with nearly perfect spherical interfaces.

  9. Computational Fluid Dynamics-Based Design Optimization Method for Archimedes Screw Blood Pumps.

    PubMed

    Yu, Hai; Janiga, Gábor; Thévenin, Dominique

    2016-04-01

    An optimization method suitable for improving the performance of Archimedes screw axial rotary blood pumps is described in the present article. In order to achieve a more robust design and to save computational resources, this method combines the advantages of the established pump design theory with modern computer-aided, computational fluid dynamics (CFD)-based design optimization (CFD-O) relying on evolutionary algorithms and computational fluid dynamics. The main purposes of this project are to: (i) integrate pump design theory within the already existing CFD-based optimization; (ii) demonstrate that the resulting procedure is suitable for optimizing an Archimedes screw blood pump in terms of efficiency. Results obtained in this study demonstrate that the developed tool is able to meet both objectives. Finally, the resulting level of hemolysis can be numerically assessed for the optimal design, as hemolysis is an issue of overwhelming importance for blood pumps.

  10. A sliding mode-based starling-like controller for implantable rotary blood pumps.

    PubMed

    Bakouri, Mohsen A; Salamonsen, Robert F; Savkin, Andrey V; AlOmari, Abdul-Hakeem H; Lim, Einly; Lovell, Nigel H

    2014-07-01

    Clinically adequate implementation of physiological control of a rotary left ventricular assist device requires a sophisticated technique such as the recently proposed method based on the Frank-Starling mechanism. In this mechanism, the stroke volume of the heart increases in response to an increase in the volume of blood filling the left ventricle at the end of diastole. To emulate this process, changes in pump speed need to automatically regulate pump flow to ensure that the combined output of the left ventricle and pump match the output of the right ventricle across changing cardiovascular states. In this approach, we exploit the linear relationship between estimated mean pump flow (Q ̅ est) and pump flow pulsatility (PIQp) in a tracking control algorithm based on sliding mode control. The immediate response of the controller was assessed using a lumped parameter model of the cardiovascular system (CVS) and pump from which could be extracted both Q ̅ est and PIQp. Two different perturbations from the resting state in the presence of left ventricular failure were tested. The first was blood loss requiring a reduction in pump flow to match the reduced output from the right ventricle and to avoid the complication of ventricular suction. The second was exercise, requiring an increase in pump flow. The sliding mode controller induced the required changes in Qp within approximately five heart beats in the blood loss simulation and eight heart beats in the exercise simulation without clinically significant transients or steady-state errors.

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

    NASA Astrophysics Data System (ADS)

    Chiang, Y.-M.; Chang, L.-C.; Tsai, M.-J.; Wang, Y.-F.; Chang, F.-J.

    2010-09-01

    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 counterpropagatiom fuzzy neural network (CFNN) 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.

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

    NASA Astrophysics Data System (ADS)

    Chiang, Y.-M.; Chang, L.-C.; Tsai, M.-J.; Wang, Y.-F.; Chang, F.-J.

    2011-01-01

    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.

  13. A Relevance Vector Machine-Based Approach with Application to Oil Sand Pump Prognostics

    PubMed Central

    Hu, Jinfei; Tse, Peter W.

    2013-01-01

    Oil sand pumps are widely used in the mining industry for the delivery of mixtures of abrasive solids and liquids. Because they operate under highly adverse conditions, these pumps usually experience significant wear. Consequently, equipment owners are quite often forced to invest substantially in system maintenance to avoid unscheduled downtime. In this study, an approach combining relevance vector machines (RVMs) with a sum of two exponential functions was developed to predict the remaining useful life (RUL) of field pump impellers. To handle field vibration data, a novel feature extracting process was proposed to arrive at a feature varying with the development of damage in the pump impellers. A case study involving two field datasets demonstrated the effectiveness of the developed method. Compared with standalone exponential fitting, the proposed RVM-based model was much better able to predict the remaining useful life of pump impellers. PMID:24051527

  14. Ignition experiment design based on γ-pumping gas lasers

    NASA Astrophysics Data System (ADS)

    Bonyushkin, E. K.; Il'kaev, R. I.; Morovov, A. P.; Pavlovskii, A. I.; Lazhintsev, B. V.; Basov, N.; Gus'kov, S. Yu.; Rosanov, V. B.; Zmitrenko, N. V.

    1996-05-01

    Comparative analysis of gas lasers pumped by γ-radiation for ignition experiment is carried out. The possibilities of frequency-time pulse shaping are discussed for these kinds of laser drivers. New type of ICF target (LIGHT-target), which is able to provide an uniform deposition of laser driver energy is proposed as a target for ignition experiment.

  15. Dipole nanolaser

    NASA Astrophysics Data System (ADS)

    Protsenko, I. E.; Uskov, A. V.; Zaimidoroga, O. A.; Samoilov, V. N.; O'Reilly, E. P.

    2005-06-01

    A “dipole” laser is proposed consisting of a nanoparticle and a two-level system with population inversion. If the threshold conditions are fulfilled, the dipole interaction between the two-level system and the nanoparticle leads to coherent oscillations in the polarization of the particles, even in the absence of an external electromagnetic field. The emitted radiation has a dipolar distribution. It does not need an optical cavity, and has a very small volume, ˜0.1μm3 , which can be important for applications in microelectronics. Estimates of the threshold conditions are carried out for a dipole laser composed of a quantum dot and a silver nanoparticle.

  16. Jet pumps for thermoacoustic applications: Design guidelines based on a numerical parameter study.

    PubMed

    Oosterhuis, Joris P; Bühler, Simon; Wilcox, Douglas; van der Meer, Theo H

    2015-10-01

    The oscillatory flow through tapered cylindrical tube sections (jet pumps) is characterized by a numerical parameter study. The shape of a jet pump results in asymmetric hydrodynamic end effects which cause a time-averaged pressure drop to occur under oscillatory flow conditions. Hence, jet pumps are used as streaming suppressors in closed-loop thermoacoustic devices. A two-dimensional axisymmetric computational fluid dynamics model is used to calculate the performance of a large number of conical jet pump geometries in terms of time-averaged pressure drop and acoustic power dissipation. The investigated geometrical parameters include the jet pump length, taper angle, waist diameter, and waist curvature. In correspondence with previous work, four flow regimes are observed which characterize the jet pump performance and dimensionless parameters are introduced to scale the performance of the various jet pump geometries. The simulation results are compared to an existing quasi-steady theory and it is shown that this theory is only applicable in a small operation region. Based on the scaling parameters, an optimum operation region is defined and design guidelines are proposed which can be directly used for future jet pump design.

  17. In vivo assessment of a new method of pulsatile perfusion based on a centrifugal pump.

    PubMed

    Herreros, Jesús; Ubilla, Matías; Berjano, Enrique J; Vila-Nuñez, Juan E; Páramo, José A; Sola, Josu; Mercé, Salvador

    2010-02-01

    The aim of this study was to assess platelet dysfunction and damage to organs after extracorporeal circulation using a pump based on a new method that adds a pulsatile flow to the continuous flow provided by a centrifugal pump. The continuous component of the total flow (2-3 L/min) is created by a Bio-Pump centrifugal pump, while the pulsatile component is created by the pulsating of an inner membrane pneumatically controlled by an intra-aortic counterpulsation balloon console (systolic volume of 37.5 mL in an asynchronous way with a frequency of 60 bpm). Six pigs were subjected to a partial cardiopulmonary bypass lasting 180 min and were sacrificed 60 min after extracorporeal circulation was suspended. The hematological study included the measurement of hematocrit, hemoglobin, leukocytes, and platelet function. The new pump did not significantly alter either platelet count or platelet function. In contrast, hematocrit and hemoglobin were significantly reduced during extracorporeal circulation (approximately 5% P = 0.011, and 2 g/dL P = 0.01, respectively). The leukocyte count during extracorporeal circulation showed a tendency to decrease, but this was not significant. In general, the short-term use of the new pump (4 h) did not cause any serious morphological damage to the heart, lung, kidney, or liver. The results suggest that the hemodynamic performance of the new pump is similar to a conventional centrifugal pump and could therefore be appropriate for use in extracorporeal circulation.

  18. MEMS based pumped liquid cooling systems for micro/nano spacecraft thermal control

    NASA Technical Reports Server (NTRS)

    Birur, G. C.; Shakkottai, P.; Sur, T. W

    2001-01-01

    The objective is to develop MEMS based pumped liquid cooling system for removing over 20 W/cm squared from high power density microelectronics and science payloads considered for future micro/nano sciencecraft.

  19. Selective detection of sub-atto-molar Streptavidin in 10(13)-fold impure sample using photonic crystal nanolaser sensors.

    PubMed

    Hachuda, Shoji; Otsuka, Shota; Kita, Shota; Isono, Toshinari; Narimatsu, Michimasa; Watanabe, Keisuke; Goshima, Yoshio; Baba, Toshihiko

    2013-05-20

    Biosensors selectively detecting a very small amount of biomarker protein in human blood are desired for early and reliable diagnoses of severe diseases. This paper reports the detection of protein (streptavidin: SA) in ultra-low concentration, with an ultra-high selectivity against contaminants, using photonic crystal nanolasers. For biotin-modified nanolasers in pure water with SA, an extremely-low detection limit of 16 zM is evaluated. Even in a mixture with 1 μM bovine serum albumin as the contaminant, 100 zM SA is detected, meaning a selectivity of 10(13). These are remarkable capabilities that are promising for practical biosensing in the medical applications mentioned above.

  20. Pump dependence of the dynamics of quantum dot based waveguide absorbers

    NASA Astrophysics Data System (ADS)

    Viktorov, Evgeny A.; Erneux, Thomas; Piwonski, Tomasz; Pulka, Jaroslaw; Huyet, Guillaume; Houlihan, John

    2012-06-01

    The nonlinear two stage recovery of quantum dot based reverse-biased waveguide absorbers is investigated experimentally and analytically as a function of the initial ground state occupation probability of the dot. The latter is controlled experimentally by the pump pulse power. The slow stage of the recovery is exponential and its basic timescale is independent of pump power. The fast stage of the recovery is a logistic function which we analyze in detail. The relative strength of slow to fast components is highlighted and the importance of higher order absorption processes at the highest pump level is demonstrated.

  1. Chemical-contrast imaging with pulse-shaping based pump-probe spectroscopy

    NASA Astrophysics Data System (ADS)

    Flynn, Daniel C.; Bhagwat, Amar R.; Ogilvie, Jennifer P.

    2013-02-01

    Ultrafast pump-probe spectroscopy and pulse-shaping techniques are providing new modes of contrast for the field of multiphoton microscopy. Endogenous species such as heme proteins show rich nonlinear spectroscopic signatures of excited state absorption, stimulated emission and ground-state bleaching. Commercially available octave-spanning Ti:sapphire oscillators offer new opportunities for imaging based on pump-probe contrast. Spatial light modulators take advantage of this large bandwidth, shaping pulses of light to selectively excite molecular structures with similar spectral properties. We present two-color pump-probe imaging of heme proteins solutions and red blood cells.

  2. Atom and Electron Pump Based on Oscillating Wells: Classical versus Quantum features

    NASA Astrophysics Data System (ADS)

    Garner, Joshua; Ruppert, Kevin; Das, Kunal

    2015-05-01

    The transport dynamics of ultracold atoms in quasi one-dimensional (1D) waveguides share much in common with that of electrons and holes in nanowires. In the latter system, biasless transport by time-varying potential, commonly called quantum pumping, has been much researched theoretically as a mechanism that can provide significant control over the current. With scant experimental success, ultracold atoms provide a promising alternate for exploring quantum pumps. Prior studies of quantum pumps have generally focused on using potential barriers as the pump elements. In this study, we undertake a first detailed study of the scattering dynamics involved in using quantum wells to drive the pumping. Specifically, we do a comparative study using quantum, classical and semiclassical picture in a common wavepacket approach that also allows direct comparison of quantum versus classical features. Notably, a static well, unlike a barrier, does not reflect; but oscillating ones do even in the classical limit, and moreover, particles can be trapped in wells indefinitely. Such features lead to distinctive features for well-based pumps that can have both practical and fundamental physics implications. Our study is done in the context of several different pump configurations. Supported by NSF Grant No. PHY-1313871 and grants from PASSHE-FPDC and Kutztown University.

  3. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    SciTech Connect

    Fernandez-Ramos, Jose; Narvarte-Fernandez, Luis; Poza-Saura, Fernando

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  4. Condition Based vs. Time Based Maintenance: Case Study on Hypergolic Pumps

    NASA Technical Reports Server (NTRS)

    Gibson, Lewis J.

    2007-01-01

    Two Pad 39B Ox pumps were monitored with the Baker Instruments Explorer Motor tester. Using the torque spectrum it was determined that Ox pump #2 had a significant peak at a frequency, which indicated lubricant fluid whirl. Similar testing on Ox pump #1 didn't indicate this peak, an indication that this pump was in good mechanical condition. Subsequent disassembly of both motors validated these findings. Ox pump #2 rear bearing showed significant wear, the front bearing showed little wear. Ox pump #1 was still within manufacturers tolerances.

  5. Monolithic III–V on Silicon Plasmonic Nanolaser Structure for Optical Interconnects

    PubMed Central

    Li, Ning; Liu, Ke; Sorger, Volker J.; Sadana, Devendra K.

    2015-01-01

    Monolithic integration of III–V semiconductor lasers with Si circuits can reduce cost and enhance performance for optical interconnects dramatically. We propose and investigate plasmonic III–V nanolasers as monolithically integrated light source on Si chips due to many advantages. First, these III–V plasmonic light sources can be directly grown on Si substrates free of crystallographic defects due to the submicron cavity footprint (250 nm × 250 nm) being smaller than the average defect free region size of the heteroepitaxial III–V material on Si. Secondly, the small lateral and vertical dimensions facilitate process co-integration with Si complementary metal-oxide-semiconductor (CMOS) in the front end of the line. Thirdly, combining with monolithically integrated CMOS circuits with low device capacitance and parasitic capacitance, the nano-cavity optoelectronic devices consume orders of magnitude less power than the conventional lasers and reduce the energy consumption. Fourthly, the modulation bandwidth of the plasmonic light-sources is enhanced to significantly higher than conventional lasers due to enhanced photon state density and transition rate. In addition, we show that these device performance are very robust after taking into account the surface recombination and variations in device fabrication processes. PMID:26369698

  6. Mitochondrial correlation microscopy and nanolaser spectroscopy - new tools for biophotonic detection of cancer in single cells.

    PubMed

    Gourley, Paul L; Hendricks, Judy K; McDonald, Anthony E; Copeland, R Guild; Barrett, Keith E; Gourley, Cheryl R; Singh, Keshav K; Naviaux, Robert K

    2005-12-01

    Currently, pathologists rely on labor-intensive microscopic examination of tumor cells using century-old staining methods that can give false readings. Emerging BioMicroNano-technologies have the potential to provide accurate, realtime, high-throughput screening of tumor cells without the need for time-consuming sample preparation. These rapid, nano-optical techniques may play an important role in advancing early detection, diagnosis, and treatment of disease. In this report, we show that laser scanning confocal microscopy can be used to identify a previously unknown property of certain cancer cells that distinguishes them, with single-cell resolution, from closely related normal cells. This property is the correlation of light scattering and the spatial organization of mitochondria. In normal liver cells, mitochondria are highly organized within the cytoplasm and highly scattering, yielding a highly correlated signal. In cancer cells, mitochondria are more chaotically organized and poorly scattering. These differences correlate with important bioenergetic disturbances that are hallmarks of many types of cancer. In addition, we review recent work that exploits the new technology of nanolaser spectroscopy using the biocavity laser to characterize the unique spectral signatures of normal and transformed cells. These optical methods represent powerful new tools that hold promise for detecting cancer at an early stage and may help to limit delays in diagnosis and treatment.

  7. CNT based thermal Brownian motor to pump water in nanodevices

    NASA Astrophysics Data System (ADS)

    Oyarzua, Elton; Zambrano, Harvey; Walther, J. H.

    2016-11-01

    Brownian molecular motors are nanoscale machines that exploit thermal fluctuations for directional motion by employing mechanisms such as the Feynman-Smoluchowski ratchet. In this study, using Non Equilibrium Molecular Dynamics, we propose a novel thermal Brownian motor for pumping water through Carbon Nanotubes (CNTs). To achieve this we impose a thermal gradient along the axis of a CNT filled with water and impose, in addition, a spatial asymmetry by fixing specific zones on the CNT in order to modify the vibrational modes of the CNT. We find that the temperature gradient and imposed spatial asymmetry drive the water flow in a preferential direction. We systematically modified the magnitude of the applied thermal gradient and the axial position of the fixed points. The analysis involves measurement of the vibrational modes in the CNTs using a Fast Fourier Transform (FFT) algorithm. We observed water flow in CNTs of 0.94, 1.4 and 2.0 nm in diameter, reaching a maximum velocity of 5 m/s for a thermal gradient of 3.3 K/nm. The proposed thermal motor is capable of delivering a continuous flow throughout a CNT, providing a useful tool for driving liquids in nanofluidic devices by exploiting thermal gradients. We aknowledge partial support from Fondecyt project 11130559.

  8. Electromagnetic liquid pistons for capillarity-based pumping

    NASA Astrophysics Data System (ADS)

    Malouin, Bernard; Olles, Joseph; Cheng, Lili; Hirsa, Amir; Vogel, Michael

    2011-11-01

    Two adjoining ferrofluid droplets can behave as an electronically-controlled oscillator or switch by an appropriate balance of magnetic, capillary, and inertial forces. Their motion can be exploited to displace a surrounding liquid, forming electromagnetic liquid pistons. Such ferrofluid pistons can pump a precise volume of liquid via finely tunable amplitudes or resonant frequencies with no solid moving parts. Here we demonstrate the use of these liquid pistons in capillarity-dominated systems for variable focal distance liquid lenses with nearly perfect spherical interfaces. These liquid/liquid lenses feature many promising qualities not previously realized together in a liquid lens, including large apertures, immunity to evaporation, invariance to orientation relative to gravity, and low driving voltages. The dynamics of these liquid pistons is examined, with experimental measurements showing good agreement with a spherical cap model. A centimeter-scale lens was shown to respond in excess of 30 Hz, with resonant frequencies over 1 kHz predicted for scaled down systems.

  9. Optimization of a photovoltaic pumping system based on the optimal control theory

    SciTech Connect

    Betka, A.; Attali, A.

    2010-07-15

    This paper suggests how an optimal operation of a photovoltaic pumping system based on an induction motor driving a centrifugal pump can be realized. The optimization problem consists in maximizing the daily pumped water quantity via the optimization of the motor efficiency for every operation point. The proposed structure allows at the same time the minimization the machine losses, the field oriented control and the maximum power tracking of the photovoltaic array. This will be attained based on multi-input and multi-output optimal regulator theory. The effectiveness of the proposed algorithm is described by simulation and the obtained results are compared to those of a system working with a constant air gap flux. (author)

  10. New inverse method of centrifugal pump blade based on free form deformation

    NASA Astrophysics Data System (ADS)

    Zhang, R. H.; Guo, M.; Yang, J. H.; Liu, Y.; Li, R. N.

    2013-12-01

    In this research, a new inverse method for centrifugal pump blade based on free form deformation is proposed, the free form deformation is used to parametric the pump blade. The blade is implanted to a trivariate control volume which is equally subdivided by control lattice. The control volume can be deformed by moving the control lattice, thereupon the object is deformed. The flow in pump is solved by using a three dimensional turbulent model. The lattice deformation function is constructed according to the gradient distribution of fluid energy along the blade and its objective distribution. Deform the blade shape continually according to the flow solve, and we can get the objective blade shape. The calculation case shows that the proposed inverse method based on FFD method is rational.

  11. A novel subcutaneous infusion delivery system based on osmotic pump: in vitro and in vivo evaluation.

    PubMed

    Gong, Wei; Ma, Rui; Mei, Danyu; Jing, Pei; Dong, Xiao; Li, Bingsheng; Yang, Yanfang; Du, Lina; Mei, Xing-Guo; Hu, Fu-Qiang

    2014-02-01

    An economical, convenient portable drug delivery system combining osmotic pump with subcutaneous infusion was developed, which was composed of three primary components: water chamber, osmotic pump chamber and support base. Ceftriaxone sodium (CRO) was selected as the model drug and osmotic pump tablets were prepared. The influence of osmotic agents on drug release profiles was evaluated. As the adjustment made by the osmotic agents was limited, the compositions of semipermeable membrane were investigated to determine significant associations of factors based on orthogonal design. The in vitro release profiles of the optimum formulation achieved to the predetermined value (15 ± 3 min for the initial release time T(i) and 5.75 ± 0.25 h for the extent release time T(e)). The pharmacokinetic profiles of this drug delivery system were evaluated in Beagle dogs. In vivo results demonstrated that the osmotic pump subcutaneous infusion administration was equivalent to intravenous injection administration in terms of bioavailability. Moreover, constant drug plasma levels with minimized fluctuations could be achieved with this osmotic pump subcutaneous infusion system, compared with intravenous injection.

  12. Cavity-free stopped-light nanolasing in nanoplasmonic heterostructures (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Hess, Ortwin

    2015-09-01

    Going beyond traditional cavity-concepts, recently conceived nanolasers employ plasmonic resonances for feedback, allowing them to concentrate light into mode volumes that are no longer limited by diffraction [1]. The use of localized surface plasmon resonances as cold-cavity modes, however, is only one route to lasing on subwavelength scales. Lasing, in fact, does not require modes predefined by geometry but merely a feedback mechanism [2]. Here we demonstrate that the concept of dispersion-less stopped-light [3] allows by combination of nanoplasmonics with quantum gain materials [4] stopped-light lasing in hybrid nanoplasmonic heterostructures. Thereby, photons are trapped and amplified in space just at the point of their emission. It will be discussed that, at the stopped-light point, a stable lasing mode can form over a finite region of gain material due to the arising local (cavity-free) feedback in the form of a sub-wavelength optical vortex. We discuss the remarkable spatio-temporal dynamics of nanoplasmonic stopped-light lasing is studied on the basis of a Maxwell-Bloch Langevin approach [4]. Moreover, a new rate-equation framework is shown to grasp the particular physics of stopped-light lasing involving [4]. The observed high-β characteristics and picosecond relaxation oscillations of cavity-free stopped-light lasing can potentially allow for the design of thresholdless plasmonic laser diodes that can be modulated with THz speeds. References [1] O Hess and KL Tsakmakidis, Science 339, 654 (2013). [2] J M Hamm and O Hess, Science 340, 1298 (2013). [3] KL Tsakmakidis, TW Pickering, JM Hamm, AF Page and O Hess, Phys Rev Lett 112, 167401 (2014). [4] T Pickering, J M Hamm, A F Page, S Wuestner and O Hess, Nature Communications 5, 4971 (2014).

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

    PubMed

    Fong, Jeffrey; Xiao, Zhiming; Takahata, Kenichi

    2015-02-21

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

  14. Determination of basal hydraulic systems based on subglacial high-pressure pump experiments

    NASA Astrophysics Data System (ADS)

    Lappegard, Gaute; Kohler, Jack

    We have conducted short-term pump experiments with pump pressures exceeding ice overburden to study the seasonality of the subglacial hydraulic system of Engabreen, Norway. Data were collected from load cells installed flush with the ice bedrock interface and pressure transducers installed in boreholes leading from bedrock tunnels underneath the glacier to the ice bedrock interface. The water-pressure recordings, seen in relation with the load-cell record, show the existence of hydraulically connected vs unconnected bed areas. Monitored boreholes have been used to inject water at high pressures. Each experiment led to the growth of a high-pressure water cavity whose spatial extent could be inferred from load-cell and pressure transducer records. Post-pump pressures were low after summer pump tests and close to ice-overburden level after winter pump experiments. We conclude that drainage takes place in a fast-flow, low-pressure, channel-based drainage system during summer, and a low-flow, high-pressure, linked-cavity drainage system during winter.

  15. Experimental performance evaluation of heat pump-based steam supply system

    NASA Astrophysics Data System (ADS)

    Kaida, T.; Sakuraba, I.; Hashimoto, K.; Hasegawa, H.

    2015-08-01

    Heat pumps have become increasingly important as a technology to reduce primary energy consumption and greenhouse effect gas emission. They are presently used mainly on residential air-conditioning and domestic hot water and are expected to spread to industrial heating processes. In 2011, Kobe Steel, Ltd. developed and commercialized two heat pump- based steam supply systems; the high efficiency steam supply system with a steam temperature of 120°C (SGH120) and the system which enables a steam temperature of 165°C (sGh165). For promoting the spread of these industrial heat pumps and enhancing the reliability of them, we investigate experimentally steam generation rate, energy efficiency and controlled performance of the SGH165 under various operating conditions on the assumption of actual different industrial processes, and evaluate technical possibilities for better performance.

  16. Instability study of a pump-turbine at no load opening based on turbulence model

    NASA Astrophysics Data System (ADS)

    Liu, J. T.; Liu, S. H.; Sun, Y. K.; Zuo, Z. G.; Wu, Y. L.; Wang, L. Q.

    2012-11-01

    A linear eddy viscosity model and a non-linear eddy viscosity model were used to simulate a centrifugal pump at an off-design point. Compared with the inner flow of experimental results, turbulence model was accurate in the calculation of the rotating stall phenomenon in the runner of low flow conditions. The turbulence model and three dimensional (3-D), unsteady flow in a pump-turbine was used to study the instability of a high-head pump-turbine at no-load opening. Fluid coupling and dynamic mesh were used to simulate the change of runner's rotational speed. Stall phenomena in the runner caused by a large incidence angle of flow at the region between stay vanes and guide vanes were analyzed. Calculations based on different moments of inertia were accomplished in order to investigate the influence of moment of inertia to the stall phenomena in the runner. The Rayleigh criterion was introduced to analyze the instability of the stall phenomena in the runner. The explicit characteristics such as the flow-rate, rotational speed, torque of the runner etc. were analyzed. Results show that the moment of inertia has great influence on the stall phenomena in the runner. The Rayleigh criterion can be used to evaluate the instability of the pump-turbine at no-load opening. The flow in the pump-turbine at runaway speed is more stable when the moment of inertia increases. The study of a pump-turbine at no-load opening can provide a basic foundation for the improvement of S characteristics.

  17. Slurry pumping: Pump performance prediction

    SciTech Connect

    Taccani, R.; Pediroda, V.; Reini, M.; Giadrossi, A.

    2000-07-01

    Centrifugal pumps are being used increasingly for transportation of slurries through pipelines. To design a slurry handling system it is essential to have a knowledge of the effects of suspended solids on the pump performance. A new test loop has been realized in the laboratory of the Energetics Department of the University of Trieste which allows pump performance to be determined at various pump speeds, with many different mixture concentrations and rheologies. The pump test rig consists of 150 mm diameter pipe with facilities for measuring suction and discharge pressure, flowrate, pump input power and speed, slurry density and temperature. In particular flowrate is measured by diverting flow into a weighing tank and timing a specified volume of slurry. An automatic PC based data acquisition system has been implemented. Preliminary tests with clear water show that performance can be measured with good repeatability and accuracy. The new test rig is used to verify the range of validity of the correlations to predict pump performance, available in literature and of that proposed by authors. This correlation, based on a Neural Network and not on a predefined analytical expression, can be easily improved with new experimental data.

  18. Micro pumping methods based on AC electrokinetics and Electrorheologically actuated PDMS valves

    NASA Astrophysics Data System (ADS)

    Soni, Gaurav; Squires, Todd; Meinhart, Carl

    2006-11-01

    We have developed 2 different micropumping methods for transporting ionic fluids through microchannels. The first method is based on Induced Charge Electroosmosis (ICEO) and AC flow field-effect. We used an AC electric field to produce a symmetric ICEO flow on a planar electrode, called `gate'. In order to break the symmetry of ICEO, we applied an additional AC voltage to the gate electrode. Such modulation of the gate potential is called field effect and produces a unidirectional pumping over the gate surface. We used micro PIV to measure pumping velocities for a range of ionic concentration, AC frequency and gate voltage. We have also conducted numerical simulations to understand the deteriorating effect of lateral conduction of surface charge on the pumping velocities. The second method is based on vibration of a flexible PDMS diaphragm actuated by an electrorheological (ER) fluid. ER fluid is a colloidal suspension exhibiting a reversible liquid-to-solid transition under an electric field. This liquid-to-solid transition can yield very high shear stress and can be used to open and close a PDMS valve. Three such valves were fabricated and actuated in a peristaltic fashion in order to achieve positive displacement pumping of fluids.

  19. Transient Stress- and Strain-Based Hemolysis Estimation in a Simplified Blood Pump

    PubMed Central

    Pauli, L.; Nam, J.; Pasquali, M.; Behr, M.

    2014-01-01

    SUMMARY We compare two approaches to numerical estimation of mechanical hemolysis in a simplified blood pump model. The stress-based model relies on the instantaneous shear stress in the blood flow, whereas the strain-based model uses an additional tensor equation to relate distortion of red blood cells to a shear stress measure. We use the newly proposed least-squares finite element method (LSFEM) to prevent negative concentration fields and show a stable and volume preserving LSFEM for the tensor equation. Application of both models to a simplified centrifugal blood pump at three different operating conditions show that the stress-based model overestimates the rate of hemolysis. The strain-based model is found to deliver lower hemolysis rates since it incorporates a more detailed description of biophysical phenomena into the simulation process. PMID:23922311

  20. Atomic-based stabilization for laser-pumped atomic clocks.

    PubMed

    Gerginov, V; Shah, V; Knappe, S; Hollberg, L; Kitching, J

    2006-06-15

    We describe a novel technique for stabilizing frequency shifts in laser-interrogated vapor-cell atomic clocks. The method suppresses frequency shifts due to changes in the laser frequency, intensity, and modulation index as well as atomic vapor density. The clock operating parameters are monitored by using the atoms themselves, rather than by using conventional schemes for laser frequency and cell temperature control. The experiment is realized using a chip-scale atomic clock. The novel atomic-based stabilization approach results in a simpler setup and improved long-term performance.

  1. Tomographic inverse estimation of aquifer properties based on pressure variations caused by transient water-supply pumping

    NASA Astrophysics Data System (ADS)

    Vesselinov, V. V.; Harp, D. R.; Koch, R. J.; Birdsell, K. H.

    2008-12-01

    Groundwater pumping of water-supply wells frequently exhibits substantial temporal and spatial variability. Wells are typically operated periodically (on daily and seasonal temporal scales), and the total production is controlled by the water-supply demand,. The pumping causes temporal and spatial variability in the water levels around the pumping wells. During the wellfield operation, water-level data are collected from the production and nearby observation wells. Water level fluctuations are a result of the manner in which the pumping is conducted, aquifer heterogeneity, and variations in other influences such as recharge, poroelastic effects, etc. The variability in aquifer stresses due to pumping can provide valuable information about aquifer properties. The supply-well pumping can be viewed as a single prolonged pumping test extending over multiple pumping cycles and including multiple pumping and observation wells. Here we discuss water level and pumping production data acquired during water-supply production from the regional aquifer at Los Alamos, New Mexico. We have performed extensive interpretation of the data using analytical and numerical techniques. The analytical techniques are applied to provide (1) initial screening of the data for measurement errors, (2) identification of correlations between the pumping and water-level variability, and (3) estimation of the large-scale properties of the aquifer. The numerical models are applied to characterize the spatial heterogeneity of the aquifer using an approach based on tomographic inverse analysis. Our results demonstrate that there are large-scale features in the aquifer that appear to control the spatial propagation of transient pumping effects. The identified aquifer heterogeneities were not previously recognized and are expected to have important effects on the potential migration of contaminants in the regional aquifer.

  2. Nano-helix based quantum transistor, charge pump and motor

    NASA Astrophysics Data System (ADS)

    Qi, Xiaoliang; Zhang, Shoucheng

    2007-03-01

    We propose several novel device concepts based on nano-scale helical wires. Applying a static electric field transverse to the helical wire induces a metal to insulator transition, enabling the construction of a new type of transistor switch. The band gap is purely determined by the applied transverse voltage, and can be continuously tuned. The resulting light-emitting-diode can emit light with a tunable color spectrum. With a quadrupolar electrode configuration, the electric field could rotate in the transverse plane, leading to a quantized dc charge current proportional to the frequency of the rotation. Such a device could be used as a new standard for the high precession measurement of the electric current. The inverse effect implies that passing an electric current through the helical wire in the presence of a transverse static electric field leads to a mechanical rotation of the helix. This effect can be used to construct nano-scale electro-mechanical motors. Finally, our methodology also enables new ways of controlling and measuring the electronic properties of helical biological molecules such as the DNA.

  3. Dynamic stress analysis of sewage centrifugal pump impeller based on two-way coupling method

    NASA Astrophysics Data System (ADS)

    Pei, Ji; Yuan, Shouqi; Yuan, Jianping

    2014-03-01

    Current research on the operational reliability of centrifugal pumps has mainly focused on hydrodynamic instability. However, the interaction between the fluid and structure has not been sufficiently considered; this interaction can cause vibration and dynamic stress, which can affect the reliability. In this study, the dynamic stresses in a single-blade centrifugal pump impeller are analysed under different operating conditions; the two-way coupling method is used to calculate the fluid-structure interaction. Three-dimensional unsteady Reynolds-averaged Navier-Stokes equations are solved with the SST k-ω turbulence model for the fluid in the whole flow passage, while transient structure dynamic analysis is used with the finite element method for the structure side. The dynamic stresses in the rotor system are computed according to the fourth strength theory. The stress results show that the highest stress is near the loose bearing and that the equivalent stress increases with the flow rate because the dynamic stresses are closely related to the pressure load. The stress distributions on the blade pressure side, suction side, leading edge, and trailing edge are each analysed for different flow rates; the highest stress distribution is found on the pressure side. On the blade pressure side, a relatively large stress is found near the trailing edge and hub side. Based on these results, a stress distribution prediction method is proposed for centrifugal pumps, which considers the interaction between the fluid and structure. The method can be used to check the dynamic stress at different flow rates when optimising the pump design to increase the pump reliability.

  4. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    PubMed Central

    Tan, Chao; Qi, Nan; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others. PMID:25861253

  5. A pressure control method for emulsion pump station based on Elman neural network.

    PubMed

    Tan, Chao; Qi, Nan; Zhou, Xin; Liu, Xinhua; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  6. Fiber-based modulated optical reflectance configuration allowing for offset pump and probe beams.

    PubMed

    Fleming, A; Folsom, C; Jensen, C; Ban, H

    2016-12-01

    A new fiber-based modulated optical reflectance configuration is developed in this work. The technique maintains the fiber-based heating laser (pump) and detection laser (probe) in close proximity at a fixed separation distance in a ceramic ferrule. The pump beam periodically heats the sample inducing thermal waves into the sample. The probe beam measures the temperature response at a known distance from the pump beam over a range of heating modulation frequencies. The thermal diffusivity of the sample may be calculated from the phase response between the input heat flux and the temperature response of a sample having a reflective surface. The unique measurement configuration is ideal for in situ measurements and has many advantages for laboratory-based systems. The design and development of the system are reported along with theoretical justification for the experimental design. The thermal diffusivities of Ge and SiC are measured and found to be within 10% of reported literature values. The diffusivity for SiO2 is measured with a relative difference of approximately 100% from the literature value when the ferrule is in contact with the sample. An additional measurement was made on the SiO2 sample with the ferrule not in contact resulting in a difference of less than 2% from the literature value. The difference in the SiO2 measurement when the ferrule is in contact with the sample is likely due to a parallel heat transfer path through the dual-fiber ferrule assembly.

  7. A practical approach for implementing risk-based inservice testing of pumps at nuclear power plants

    SciTech Connect

    Hartley, R.S.; Maret, D.; Seniuk, P.; Smith, L.

    1996-12-01

    The American Society of Mechanical Engineers (ASME) Center for Research and Technology Development`s (CRTD) Research Task Force on Risk-Based Inservice Testing has developed guidelines for risk-based inservice testing (IST) of pumps and valves. These guidelines are intended to help the ASME Operation and Maintenance (OM) Committee to enhance plant safety while focussing appropriate testing resources on critical components. This paper describes a practical approach for implementing those guidelines for pumps at nuclear power plants. The approach, as described in this paper, relies on input, direction, and assistance from several entities such as the ASME Code Committees, United States Nuclear Regulatory Commission (NRC), and the National Laboratories, as well as industry groups and personnel with applicable expertise. Key parts of the risk-based IST process that are addressed here include: identification of important failure modes, identification of significant failure causes, assessing the effectiveness of testing and maintenance activities, development of alternative testing and maintenance strategies, and assessing the effectiveness of alternative testing strategies with present ASME Code requirements. Finally, the paper suggests a method of implementing this process into the ASME OM Code for pump testing.

  8. Fiber-based modulated optical reflectance configuration allowing for offset pump and probe beams

    NASA Astrophysics Data System (ADS)

    Fleming, A.; Folsom, C.; Jensen, C.; Ban, H.

    2016-12-01

    A new fiber-based modulated optical reflectance configuration is developed in this work. The technique maintains the fiber-based heating laser (pump) and detection laser (probe) in close proximity at a fixed separation distance in a ceramic ferrule. The pump beam periodically heats the sample inducing thermal waves into the sample. The probe beam measures the temperature response at a known distance from the pump beam over a range of heating modulation frequencies. The thermal diffusivity of the sample may be calculated from the phase response between the input heat flux and the temperature response of a sample having a reflective surface. The unique measurement configuration is ideal for in situ measurements and has many advantages for laboratory-based systems. The design and development of the system are reported along with theoretical justification for the experimental design. The thermal diffusivities of Ge and SiC are measured and found to be within 10% of reported literature values. The diffusivity for SiO2 is measured with a relative difference of approximately 100% from the literature value when the ferrule is in contact with the sample. An additional measurement was made on the SiO2 sample with the ferrule not in contact resulting in a difference of less than 2% from the literature value. The difference in the SiO2 measurement when the ferrule is in contact with the sample is likely due to a parallel heat transfer path through the dual-fiber ferrule assembly.

  9. Differential Brillouin fiber sensor based on phase difference on double-sideband pump wave

    NASA Astrophysics Data System (ADS)

    Lin, Wenqiao; Hong, Xiaobin; Yang, Zhisheng; Wu, Jian; Lin, Jintong

    2015-06-01

    A configuration based on phase difference on a double-sideband pump wave is proposed to detect the differential variation of temperature or strain in single-mode optical fibers. In our configuration, a probe wave only experiences a differential Brillouin gain contributed by the perturbation of temperature or strain in the sensing fiber. As a result, the power limitation of the probe wave can be alleviated and the photodetector in our configuration does not easily become saturated in the case of a longer sensing range. The spatial resolution is determined by the duration of the phase difference on the two sidebands and the signal-to-noise of our system is nearly twice as high as that of a differential pulse-width pair Brillouin optical time domain analysis sensor since a π-phase shift on the pump wave is employed. The properties and performances of our method are also theoretically derived and experimentally validated.

  10. Long-distance fiber sensor system based on the second-order Raman pump and amplification

    NASA Astrophysics Data System (ADS)

    Dong, B.; Hu, J.; Chen, Z.; Yu, C.

    2012-07-01

    We demonstrate a novel technique to realize a long-distance fiber sensor system based on the second-order Raman pump and amplification. With the second-order Raman pump and amplification, a gain spectrum around 1582-nm is achieved. It serves as not only the optical source for the remote fiber sensor but also the filter to intensity modulated the wavelength shift of the fiber sensor. A long-distance fiber strain sensor system is demonstrated by adopting a fiber Fabry-Pérot sensor. Experimental results show that the wavelength shift of the sensor in response to the strain is simultaneously intensity modulated by the steep slope with a high sensitivity, while it is temperature insensitive. With the side gain spectrum served as a quasi-linear filter, the sensor can also be quasi-linearly intensity-modulated.

  11. Thermodynamics of information processing based on enzyme kinetics: An exactly solvable model of an information pump

    NASA Astrophysics Data System (ADS)

    Cao, Yuansheng; Gong, Zongping; Quan, H. T.

    2015-06-01

    Motivated by the recent proposed models of the information engine [Proc. Natl. Acad. Sci. USA 109, 11641 (2012), 10.1073/pnas.1204263109] and the information refrigerator [Phys. Rev. Lett. 111, 030602 (2013), 10.1103/PhysRevLett.111.030602], we propose a minimal model of the information pump and the information eraser based on enzyme kinetics. This device can either pump molecules against the chemical potential gradient by consuming the information to be encoded in the bit stream or (partially) erase the information initially encoded in the bit stream by consuming the Gibbs free energy. The dynamics of this model is solved exactly, and the "phase diagram" of the operation regimes is determined. The efficiency and the power of the information machine is analyzed. The validity of the second law of thermodynamics within our model is clarified. Our model offers a simple paradigm for the investigating of the thermodynamics of information processing involving the chemical potential in small systems.

  12. Noninvasive activity-based control of an implantable rotary blood pump: comparative software simulation study.

    PubMed

    Karantonis, Dean M; Lim, Einly; Mason, David G; Salamonsen, Robert F; Ayre, Peter J; Lovell, Nigel H

    2010-02-01

    A control algorithm for an implantable centrifugal rotary blood pump (RBP) based on a noninvasive indicator of the implant recipient's activity level has been proposed and evaluated in a software simulation environment. An activity level index (ALI)-derived from a noninvasive estimate of heart rate and the output of a triaxial accelerometer-forms the noninvasive indicator of metabolic energy expenditure. Pump speed is then varied linearly according to the ALI within a defined range. This ALI-based control module operates within a hierarchical multiobjective framework, which imposes several constraints on the operating region, such as minimum flow and minimum speed amplitude thresholds. Three class IV heart failure (HF) cases of varying severity were simulated under rest and exercise conditions, and a comparison with other popular RBP control strategies was performed. Pump flow increases of 2.54, 1.94, and 1.15 L/min were achieved for the three HF cases, from rest to exercise. Compared with constant speed control, this represents a relative flow change of 30.3, 19.8, and -15.4%, respectively. Simulations of the proposed control algorithm exhibited the effective intervention of each constraint, resulting in an improved flow response and the maintenance of a safe operating condition, compared with other control modes.

  13. Selective detection of sub-atto-molar streptavidin in 1013 fold impure sample using nanoslot photonic crystal nanolaser

    NASA Astrophysics Data System (ADS)

    Hachuda, Shoji; Otsuka, Shota; Isono, Toshinari; Watanabe, Keisuke; Baba, Toshihiko

    2013-02-01

    Biosensors which can selectively detect a very small amount of biomarker protein in human blood are desired toward early diagnoses of severe diseases. However, no methods simultaneously satisfy the requirements such as high sensitivity, high selectivity, simple detection, and immediacy. We succeeded in detecting ultra-low-concentration streptavidin (SA) even in a highly impure sample using nanoslot photonic crystal (PC) nanolasers. This nanolaser consists of GaInAsP semiconductor slab with a periodic airhole array. Since the total device area is no larger than 20 × 20 μm2, highthroughput fabrication is possible even using e-beam lithography. Moreover, it is easy to operate by photopumping through free-space optics. Since the evanescent wave of the laser mode penetrates from the PC slab, the laser wavelength changes sensitively to the environmental index. In the sensing experiment, we first functionalized the devices with biotin, and then measured the wavelength in ultrapure water before and after immersing in the solutions with various concentrations of SA. As a result, we evaluated that the detection limit of SA is 16 zM. In another experiment, we put 1 μM BSA into the solution as a contaminant, and repeated the same measurement. We detected 100 zM SA even in the impure solution only when biotin is functionalized in advance, meaning a selectivity ratio (BSA / SA) of 1013. Thus this device achieves unprecedentedly high sensitivity and selectivity in addition to the simple fabrication and fast sensing. It is very promising as a point of care device for medical diagnoses.

  14. 1-μm-pumped OPO based on orientation-patterned GaP

    NASA Astrophysics Data System (ADS)

    Pomeranz, Leonard A.; Schunemann, Peter G.; Magarrell, Daniel J.; McCarthy, John C.; Zawilski, Kevin T.; Zelmon, David E.

    2015-03-01

    Orientation patterned gallium phosphide (OP-GaP) is a new nonlinear optical (NLO) crystal which exhibits the highest nonlinear coefficient (d14=70.6 pm/V) and the longest infrared cut-off (12.5 μm) of any quasi-phase-matched (QPM) material that can be pumped at 1-μm without significant two-photon absorption. Here we report the first 1064nm-pumped OPO based on bulk OP-GaP. Multi-grating OP-GaP QPM structures were grown by producing an inverted GaP layer by polar-on-nonpolar molecular beam epitaxy (MBE), lithographically patterning, reactive ion etching, and regrowing by MBE to yield templates for subsequent bulk growth by low-pressure hydride vapor phase epitaxy (LP-HVPE). The pump source was a diode-end-pumped Nd:YVO4 monoblock laser with an RTP high-voltage Q-switch (1064 nm, 1W, 10kHz, 3.3 ns) which was linearly polarized along the <100> orientation of the AR-coated 16.5 x 6.3 x 1.1 mm3 OP-GaP crystal (800-μm thick HVPE layer, 20.8 μm grating period only 150 μm thick) mounted on a copper blocked maintained at 20°C by a thermo-electric cooler. The OPO cavity was a linear resonator with 10-cm ROC mirrors coated for DRO operation (85%R at signal, 55%R at idler). The pump 4σ-diameter at the crystal face was 175 μm. The observed OPO signal (idler) threshold was 533 mW (508 mW) with a slope efficiency of 4% (1%) and maximum output power 15 mW (4 mW). The signal (1342 nm) and idler (4624 nm) output wavelengths agreed well with sellemier predictions. Orange parasitic output at 601.7nm corresponded to 9th order QPM sum frequency mixing of the 1064-nm pump and the 1385-nm signal.

  15. Holmium Doped Solid State Laser Resonantly Pumped and Q-Switched by Novel GaSb-Based Photonic Devices

    DTIC Science & Technology

    2011-08-31

    demonstrated for all devices. High power 1.95µm type-I quantum-well GaSb-based diode lasers were used to pump fluoride glass holmium doped fiber...II-VI semiconductors, novel type-II quantum well Sb-based semiconductors, and holmium doped crystals, glasses and fibers can be achieved. The...resonant pumping of the holmium doped fiber laser was demonstrated in this work. (a).1. High power ~2.2 µm lasers with broadened waveguide design

  16. Finite Volume Based Computer Program for Ground Source Heat Pump System

    SciTech Connect

    Menart, James A.

    2013-02-22

    This report is a compilation of the work that has been done on the grant DE-EE0002805 entitled ?Finite Volume Based Computer Program for Ground Source Heat Pump Systems.? The goal of this project was to develop a detailed computer simulation tool for GSHP (ground source heat pump) heating and cooling systems. Two such tools were developed as part of this DOE (Department of Energy) grant; the first is a two-dimensional computer program called GEO2D and the second is a three-dimensional computer program called GEO3D. Both of these simulation tools provide an extensive array of results to the user. A unique aspect of both these simulation tools is the complete temperature profile information calculated and presented. Complete temperature profiles throughout the ground, casing, tube wall, and fluid are provided as a function of time. The fluid temperatures from and to the heat pump, as a function of time, are also provided. In addition to temperature information, detailed heat rate information at several locations as a function of time is determined. Heat rates between the heat pump and the building indoor environment, between the working fluid and the heat pump, and between the working fluid and the ground are computed. The heat rates between the ground and the working fluid are calculated as a function time and position along the ground loop. The heating and cooling loads of the building being fitted with a GSHP are determined with the computer program developed by DOE called ENERGYPLUS. Lastly COP (coefficient of performance) results as a function of time are provided. Both the two-dimensional and three-dimensional computer programs developed as part of this work are based upon a detailed finite volume solution of the energy equation for the ground and ground loop. Real heat pump characteristics are entered into the program and used to model the heat pump performance. Thus these computer tools simulate the coupled performance of the ground loop and the heat pump

  17. Recovery Act: Finite Volume Based Computer Program for Ground Source Heat Pump Systems

    SciTech Connect

    James A Menart, Professor

    2013-02-22

    This report is a compilation of the work that has been done on the grant DE-EE0002805 entitled Finite Volume Based Computer Program for Ground Source Heat Pump Systems. The goal of this project was to develop a detailed computer simulation tool for GSHP (ground source heat pump) heating and cooling systems. Two such tools were developed as part of this DOE (Department of Energy) grant; the first is a two-dimensional computer program called GEO2D and the second is a three-dimensional computer program called GEO3D. Both of these simulation tools provide an extensive array of results to the user. A unique aspect of both these simulation tools is the complete temperature profile information calculated and presented. Complete temperature profiles throughout the ground, casing, tube wall, and fluid are provided as a function of time. The fluid temperatures from and to the heat pump, as a function of time, are also provided. In addition to temperature information, detailed heat rate information at several locations as a function of time is determined. Heat rates between the heat pump and the building indoor environment, between the working fluid and the heat pump, and between the working fluid and the ground are computed. The heat rates between the ground and the working fluid are calculated as a function time and position along the ground loop. The heating and cooling loads of the building being fitted with a GSHP are determined with the computer program developed by DOE called ENERGYPLUS. Lastly COP (coefficient of performance) results as a function of time are provided. Both the two-dimensional and three-dimensional computer programs developed as part of this work are based upon a detailed finite volume solution of the energy equation for the ground and ground loop. Real heat pump characteristics are entered into the program and used to model the heat pump performance. Thus these computer tools simulate the coupled performance of the ground loop and the heat pump. The

  18. High repetition pump-and-probe photoemission spectroscopy based on a compact fiber laser system.

    PubMed

    Ishida, Y; Otsu, T; Ozawa, A; Yaji, K; Tani, S; Shin, S; Kobayashi, Y

    2016-12-01

    The paper describes a time-resolved photoemission (TRPES) apparatus equipped with a Yb-doped fiber laser system delivering 1.2-eV pump and 5.9-eV probe pulses at the repetition rate of 95 MHz. Time and energy resolutions are 11.3 meV and ∼310 fs, respectively, the latter is estimated by performing TRPES on a highly oriented pyrolytic graphite (HOPG). The high repetition rate is suited for achieving high signal-to-noise ratio in TRPES spectra, thereby facilitating investigations of ultrafast electronic dynamics in the low pump fluence (p) region. TRPES of polycrystalline bismuth (Bi) at p as low as 30 nJ/mm(2) is demonstrated. The laser source is compact and is docked to an existing TRPES apparatus based on a 250-kHz Ti:sapphire laser system. The 95-MHz system is less prone to space-charge broadening effects compared to the 250-kHz system, which we explicitly show in a systematic probe-power dependency of the Fermi cutoff of polycrystalline gold. We also describe that the TRPES response of an oriented Bi(111)/HOPG sample is useful for fine-tuning the spatial overlap of the pump and probe beams even when p is as low as 30 nJ/mm(2).

  19. High repetition pump-and-probe photoemission spectroscopy based on a compact fiber laser system

    NASA Astrophysics Data System (ADS)

    Ishida, Y.; Otsu, T.; Ozawa, A.; Yaji, K.; Tani, S.; Shin, S.; Kobayashi, Y.

    2016-12-01

    The paper describes a time-resolved photoemission (TRPES) apparatus equipped with a Yb-doped fiber laser system delivering 1.2-eV pump and 5.9-eV probe pulses at the repetition rate of 95 MHz. Time and energy resolutions are 11.3 meV and ˜310 fs, respectively, the latter is estimated by performing TRPES on a highly oriented pyrolytic graphite (HOPG). The high repetition rate is suited for achieving high signal-to-noise ratio in TRPES spectra, thereby facilitating investigations of ultrafast electronic dynamics in the low pump fluence (p) region. TRPES of polycrystalline bismuth (Bi) at p as low as 30 nJ/mm2 is demonstrated. The laser source is compact and is docked to an existing TRPES apparatus based on a 250-kHz Ti:sapphire laser system. The 95-MHz system is less prone to space-charge broadening effects compared to the 250-kHz system, which we explicitly show in a systematic probe-power dependency of the Fermi cutoff of polycrystalline gold. We also describe that the TRPES response of an oriented Bi(111)/HOPG sample is useful for fine-tuning the spatial overlap of the pump and probe beams even when p is as low as 30 nJ/mm2.

  20. A Laminar Flow-Based Microfluidic Tesla Pump via Lithography Enabled 3D Printing.

    PubMed

    Habhab, Mohammed-Baker; Ismail, Tania; Lo, Joe Fujiou

    2016-11-23

    Tesla turbine and its applications in power generation and fluid flow were demonstrated by Nicholas Tesla in 1913. However, its real-world implementations were limited by the difficulty to maintain laminar flow between rotor disks, transient efficiencies during rotor acceleration, and the lack of other applications that fully utilize the continuous flow outputs. All of the aforementioned limits of Tesla turbines can be addressed by scaling to the microfluidic flow regime. Demonstrated here is a microscale Tesla pump designed and fabricated using a Digital Light Processing (DLP) based 3D printer with 43 µm lateral and 30 µm thickness resolutions. The miniaturized pump is characterized by low Reynolds number of 1000 and a flow rate of up to 12.6 mL/min at 1200 rpm, unloaded. It is capable of driving a mixer network to generate microfluidic gradient. The continuous, laminar flow from Tesla turbines is well-suited to the needs of flow-sensitive microfluidics, where the integrated pump will enable numerous compact lab-on-a-chip applications.

  1. A Laminar Flow-Based Microfluidic Tesla Pump via Lithography Enabled 3D Printing

    PubMed Central

    Habhab, Mohammed-Baker; Ismail, Tania; Lo, Joe Fujiou

    2016-01-01

    Tesla turbine and its applications in power generation and fluid flow were demonstrated by Nicholas Tesla in 1913. However, its real-world implementations were limited by the difficulty to maintain laminar flow between rotor disks, transient efficiencies during rotor acceleration, and the lack of other applications that fully utilize the continuous flow outputs. All of the aforementioned limits of Tesla turbines can be addressed by scaling to the microfluidic flow regime. Demonstrated here is a microscale Tesla pump designed and fabricated using a Digital Light Processing (DLP) based 3D printer with 43 µm lateral and 30 µm thickness resolutions. The miniaturized pump is characterized by low Reynolds number of 1000 and a flow rate of up to 12.6 mL/min at 1200 rpm, unloaded. It is capable of driving a mixer network to generate microfluidic gradient. The continuous, laminar flow from Tesla turbines is well-suited to the needs of flow-sensitive microfluidics, where the integrated pump will enable numerous compact lab-on-a-chip applications. PMID:27886051

  2. A dynamic model of mobile concrete pump boom based on discrete time transfer matrix method

    NASA Astrophysics Data System (ADS)

    Ren, Wu; Wu, Yunxin; Zhang, Zhaowei

    2013-12-01

    Mobile concrete pump boom is typical multibody large-scale motion manipulator. Due to posture constantly change in working process, kinematic rule and dynamic characteristic are difficult to solve. A dynamics model of a mobile concrete pump boom is established based on discrete time transfer matrix method (DTTMM). The boom system is divided into sub-structure A and substructure B. Sub-structure A is composed by the 1st boom and hydraulic actuator as well as the support. And substructure B is consists of the other three booms and corresponding hydraulic actuators. In the model, the booms and links are regarded as rigid elements and the hydraulic cylinders are equivalent to spring-damper. The booms are driven by the controllable hydraulic actuators. The overall dynamic equation and transfer matrix of the model can be assembled by sub-structures A and B. To get a precise result, step size and integration parameters are studied then. Next the tip displacement is calculated and compared with the result of ADAMS software. The displacement and rotation angle curves of the proposed method fit well with the ADAMS model. Besides it is convenient in modeling and saves time. So it is suitable for mobile concrete pump boom real-time monitoring and dynamic analysis. All of these provide reference to boom optimize and engineering application of such mechanisms.

  3. Holmium Doped Solid State Laser Resonantly Pumped and Q-Switched by Novel GaSb-Based Photonic Devices

    DTIC Science & Technology

    2011-08-31

    collection of information if it does not display a currently valid OMB control number. 31-08-2011 FINAL 01-03-2008 --- 31-05-2011 Holmium Doped Solid State...release Diode pumped holmium doped fiber laser was developed in cooperation with Dr. Stuart Jackson (University of Sydney, Australia) in the framework...40 C in CW regime. Holmium doped fiber laser, resonant pumping, diode pumped, high power diode lasers, GaSb-based, type-I quantum-well U U U UU AFRL

  4. High-power EDFA pumped by P-doped fiber-based Raman converter

    NASA Astrophysics Data System (ADS)

    Kurkov, Andrey S.; Paramonov, Vladimir M.; Egorova, Olga N.; Dianov, Eugeni M.; Yashkov, M. V.; Guryanov, Alexei N.; Zalevsky, Igor D.; Goncharov, S. E.

    2002-05-01

    In this work we have tested characteristics of EDFA based on a single-mode Er-doped fiber, pumped at 1480 nm by two-stage Raman fiber converter. As an active media of Raman fiber converter a single-mode fiber with phosphorus doped core was used. The conversion efficiency of Raman converter was measured to be 36%. Output power of EDFA as high as 26 dBm was achieved at wavelengths 1554 and 1582 nm corresponding to C and L-band of WDM systems.

  5. Vane Pump Casing Machining of Dumpling Machine Based on CAD/CAM

    NASA Astrophysics Data System (ADS)

    Huang, Yusen; Li, Shilong; Li, Chengcheng; Yang, Zhen

    Automatic dumpling forming machine is also called dumpling machine, which makes dumplings through mechanical motions. This paper adopts the stuffing delivery mechanism featuring the improved and specially-designed vane pump casing, which can contribute to the formation of dumplings. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on UG and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.

  6. Small-signal modelling and control of photovoltaic based water pumping system.

    PubMed

    Ghosh, Arun; Ganesh Malla, Siva; Narayan Bhende, Chandrasekhar

    2015-07-01

    This paper studies small-signal modelling and control design for a photovoltaic (PV) based water pumping system without energy storage. First, the small-signal model is obtained and then, using this model, two proportional-integral (PI) controllers, where one controller is used to control the dc-link voltage and the other one to control the speed of induction motor, are designed to meet control goals such as settling time and peak overshoot of the closed loop responses. The loop robustness of the design is also studied. For a given set of system parameters, simulations are carried out to validate the modelling and the control design.

  7. [94 km Brillouin distributed optical fiber sensors based on ultra-long fiber ring laser pumping].

    PubMed

    Yuan, Cheng-Xu; Wang, Zi-Nan; Jia, Xin-Hong; Li, Jin; Yan, Xiao-Dong; Cui, An-Bin

    2014-05-01

    A novel optical amplification configuration based on ultra-long fiber laser with a ring cavity was proposed and applied to Brillouin optical time-domain analysis (BOTDA) sensing system, in order to extend the measurement distance significantly. The parameters used in the experiment were optimized, considering the main limitations of the setup, such as depletion, self-phase modulation (SPM) and pump-signal relative intensity noise (RIN) transfer. Through analyzing Brillouin gain spectrum, we demonstrated distributed sensing over 94 km of standard single-mode fiber with 3 meter spatial resolution and strain/temperature accuracy of 28 /1. 4 degree C.

  8. Compact Diode-Side-Pumped Stimulated Raman Laser Based on a KGW:Nd Crystal

    NASA Astrophysics Data System (ADS)

    Bezyazychnaya, T. V.; Bogdanovich, M. V.; Grigor'ev, A. V.; Lantsov, K. I.; Lebiadok, Y. V.; Leptchenkov, K. V.; Ryabtsev, A. G.; Ryabtsev, G. I.; Shpak, P. V.; Schemelev, M. A.

    2015-07-01

    We have studied an all solid-state diode-side-pumped laser which lases in the nominally eye-safe spectral range of ~1.5-1.6 μm. The optical configuration of the laser is based on using a potassium gadolinium tungstate crystal doped with neodymium ions, in which lasing occurs at a wavelength of λ = 1.351 μm and stimulated Raman selfconversion occurs to the first Stokes component (λ = 1.538 μm). The maximum output pulse energy was 17 mJ and 7 mJ for repetition frequencies of respectively 1 Hz and 10 Hz.

  9. Predicting performance of axial pump inducer of LOX booster turbo-pump of staged combustion cycle based rocket engine using CFD

    NASA Astrophysics Data System (ADS)

    Mishra, Arpit; Ghosh, Parthasarathi

    2015-12-01

    For low cost, high thrust, space missions with high specific impulse and high reliability, inert weight needs to be minimized and thereby increasing the delivered payload. Turbopump feed system for a liquid propellant rocket engine (LPRE) has the highest power to weight ratio. Turbopumps are primarily equipped with an axial flow inducer to achieve the high angular velocity and low suction pressure in combination with increased system reliability. Performance of the turbopump strongly depends on the performance of the inducer. Thus, for designing a LPRE turbopump, demands optimization of the inducer geometry based on the performance of different off-design operating regimes. In this paper, steady-state CFD analysis of the inducer of a liquid oxygen (LOX) axial pump used as a booster pump for an oxygen rich staged combustion cycle rocket engine has been presented using ANSYS® CFX. Attempts have been made to obtain the performance characteristic curves for the LOX pump inducer. The formalism has been used to predict the performance of the inducer for the throttling range varying from 80% to 113% of nominal thrust and for the different rotational velocities from 4500 to 7500 rpm. The results have been analysed to determine the region of cavitation inception for different inlet pressure.

  10. A Fault Diagnosis Methodology for Gear Pump Based on EEMD and Bayesian Network

    PubMed Central

    Liu, Zengkai; Liu, Yonghong; Shan, Hongkai; Cai, Baoping; Huang, Qing

    2015-01-01

    This paper proposes a fault diagnosis methodology for a gear pump based on the ensemble empirical mode decomposition (EEMD) method and the Bayesian network. Essentially, the presented scheme is a multi-source information fusion based methodology. Compared with the conventional fault diagnosis with only EEMD, the proposed method is able to take advantage of all useful information besides sensor signals. The presented diagnostic Bayesian network consists of a fault layer, a fault feature layer and a multi-source information layer. Vibration signals from sensor measurement are decomposed by the EEMD method and the energy of intrinsic mode functions (IMFs) are calculated as fault features. These features are added into the fault feature layer in the Bayesian network. The other sources of useful information are added to the information layer. The generalized three-layer Bayesian network can be developed by fully incorporating faults and fault symptoms as well as other useful information such as naked eye inspection and maintenance records. Therefore, diagnostic accuracy and capacity can be improved. The proposed methodology is applied to the fault diagnosis of a gear pump and the structure and parameters of the Bayesian network is established. Compared with artificial neural network and support vector machine classification algorithms, the proposed model has the best diagnostic performance when sensor data is used only. A case study has demonstrated that some information from human observation or system repair records is very helpful to the fault diagnosis. It is effective and efficient in diagnosing faults based on uncertain, incomplete information. PMID:25938760

  11. A Fault Diagnosis Methodology for Gear Pump Based on EEMD and Bayesian Network.

    PubMed

    Liu, Zengkai; Liu, Yonghong; Shan, Hongkai; Cai, Baoping; Huang, Qing

    2015-01-01

    This paper proposes a fault diagnosis methodology for a gear pump based on the ensemble empirical mode decomposition (EEMD) method and the Bayesian network. Essentially, the presented scheme is a multi-source information fusion based methodology. Compared with the conventional fault diagnosis with only EEMD, the proposed method is able to take advantage of all useful information besides sensor signals. The presented diagnostic Bayesian network consists of a fault layer, a fault feature layer and a multi-source information layer. Vibration signals from sensor measurement are decomposed by the EEMD method and the energy of intrinsic mode functions (IMFs) are calculated as fault features. These features are added into the fault feature layer in the Bayesian network. The other sources of useful information are added to the information layer. The generalized three-layer Bayesian network can be developed by fully incorporating faults and fault symptoms as well as other useful information such as naked eye inspection and maintenance records. Therefore, diagnostic accuracy and capacity can be improved. The proposed methodology is applied to the fault diagnosis of a gear pump and the structure and parameters of the Bayesian network is established. Compared with artificial neural network and support vector machine classification algorithms, the proposed model has the best diagnostic performance when sensor data is used only. A case study has demonstrated that some information from human observation or system repair records is very helpful to the fault diagnosis. It is effective and efficient in diagnosing faults based on uncertain, incomplete information.

  12. Efficient baffle prevents oil backstreaming in diffusion pumps

    NASA Technical Reports Server (NTRS)

    Meneghetti, J. R.

    1972-01-01

    High vacuum diffusion pump baffle, positioned immediately above pump stack, prevents vaporized pumping oil from entering and contaminating test chamber. Pumping vapors are collected and condensed on the baffle and flow back to pump base reservoir.

  13. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Properties of Graphene Based Parametric Pump

    NASA Astrophysics Data System (ADS)

    Luo, Song-Lin; Wei, Ya-Dong

    2009-11-01

    The adiabatic parametric electron pump of the infinite zigzag graphene ribbons and the infinite armchair graphene ribbons is investigated by the tight binding method. The pumping signals are added by two gates around the ribbons. It is shown that the dc current can be pumped out by cyclically varying the two gate voltages and the pumped current strongly depends on the driving frequency, the pumping amplitude and the phase difference of the gate voltages. The pumped current is mediated by the graphene energy levels and its peaks occur around the energies where transmission coefficients and density of states are large. The pump current may give one peak or two opposite peaks corresponding to each transmission peak or transmission pair peaks. The height and width of the current peaks increase with the amplitude of the pumping driving voltages. The pumped current is antisymmetric about the phase difference varphi = π and for small pumping amplitude the pumped current is a sinusoidal function of the phase difference. Some graphene ribbons, although with different widths, have very similar contours of the transmission coefficients and give the same pumped current figures.

  14. Comparison of tunable lasers based on diode pumped Tm-doped crystals

    NASA Astrophysics Data System (ADS)

    Šulc, Jan; Jelínková, Helena; Koranda, Petr; Černý, Pavel; Jabczyński, Jan K.; Żendzian, Waldemar; Kwiatkowski, Jacek; Urata, Yoshiharu; Higuchi, Mikio

    2008-12-01

    We report on continuously tunable operation of a diode pumped lasers based on Tm-doped materials, emitting in the 1.8 - 2.μ1 m spectral band. In our study we compare results obtained with three various single crystals doped by Tm3+ ions: Yttrium Aluminum perovskite YAP (YAlO3), Gadolinium orthovanadate GdVO4, and Yttrium Lithium Fluoride YLF (YLiF4). Following samples were available: the 3mm long a-cut crystal rod of Tm:YAP with 4% at. Tm/Y (diameter 3 mm); the 8mm long b-cut crystal rod of Tm:YLF with 3.5% at. Tm/Y (diameter 3 mm); the 2.7mm long a-cut crystal block of Tm:GdVO4 with 2% at. Tm/Gd (crystal face 5×3 mm). For active medium pumping, the laser diode radiation was used. Because the tested samples differs significantly in absorption spectra, two fibre-coupled (core diameter 400 µm) temperature-tuned laser diodes were used: first operating at wavelength 793nm was used for Tm:YAP and Tm:YLF; the second operating at wavelength 802nm was used for Tm:GdVO4. In both cases, the continuous power up to 20W was available for pumping. The diode radiation was focused into the active crystal by two achromatic doublet lenses with the focal length f = 75 mm. The measured radius of pumping beam focus inside the crystal was 260 µm. The longitudinally diode pumped crystals were tested in linear, 80mm long, hemispherical laser cavity. The curved (radius 150mm) output coupler reflectivity was ~ 97 % in range from 1.8 up to 2.1 μm. The pumping flat mirror had maximal reflectivity in this range and it had high transmission around 0.8 μm. A 1.5mm thick birefringent plate made from quartz (Lyot filter) inserted under a Brewster's angle was used as a tuning element. This plate was placed inside the resonator between the crystal and the output coupler. Using Tm:YAP crystal, the maximal output power of 2.8W in this set-up was obtained. The laser could be tuned from 1865nm up to 2036nm with a maximum at 1985 nm. Laser based on Tm:YLF crystal was tunable from 1835nm up to

  15. Hybrid distributed Raman amplification combining random fiber laser based 2nd-order and low-noise LD based 1st-order pumping.

    PubMed

    Jia, Xin-Hong; Rao, Yun-Jiang; Yuan, Cheng-Xu; Li, Jin; Yan, Xiao-Dong; Wang, Zi-Nan; Zhang, Wei-Li; Wu, Han; Zhu, Ye-Yu; Peng, Fei

    2013-10-21

    A configuration of hybrid distributed Raman amplification (H-DRA), that is formed by incorporating a random fiber laser (RFL) based 2nd-order pump and a low-noise laser-diode (LD) based 1st-order pump, is proposed in this paper. In comparison to conventional bi-directional 1st-order DRA, the effective noise figure (ENF) is found to be lower by amount of 0 to 4 dB due to the RFL-based 2nd-order pump, depending on the on-off gain, while the low-noise 1st-order Raman pump is used for compensating the worsened signal-to-noise ratio (SNR) in the vicinity towards the far end of the fiber and avoiding the potential nonlinear impact induced by excess injection of pump power and suppressing the pump-signal relative intensity noise (RIN) transfer. As a result, the gain distribution can be optimized along ultra-long fiber link, due to combination of the 2nd-order RFL and low-noise 1st-order pumping, making the transmission distance be extended significantly. We utilized such a configuration to achieve ultra-long-distance distributed sensing based on Brillouin optical time-domain analysis (BOTDA). A repeater-less sensing distance record of up to 154.4 km with 5 m spatial resolution and ~ ± 1.4 °C temperature uncertainty is successfully demonstrated.

  16. Quantification of the secondary flow in a radial coupled centrifugal blood pump based on particle tracking velocimetry.

    PubMed

    Watanabe, Nobuo; Masuda, Takaya; Iida, Tomoya; Kataoka, Hiroyuki; Fujimoto, Tetsuo; Takatani, Setsuo

    2005-01-01

    Secondary flow in the centrifugal blood pump helps to enhance the washout effect and to minimize thrombus formation. On the other hand, it has an adverse effect on pump efficiency. Excessive secondary flow may induce hemolytic effects. Understanding the secondary flow is thus important to the design of a compact, efficient, biocompatible blood pump. This study examined the secondary flow in a radial coupled centrifugal blood pump based on a simple particle tracking velocimetry (PTV) technique. A radial magnetically coupled centrifugal blood pump has a bell-shaped narrow clearance between the impeller inner radius and the pump casing. In order to vary the flow levels through the clearance area, clearance widths of 0.25 mm and 0.50 mm and impeller washout holes with diameters of 0 mm, 2.5 mm, and 4 mm were prepared. A high-speed video camera (2000 frames per second) was used to capture the particle images from which radial flow components were derived. The flow in the space behind the impeller was assumed to be laminar and Couette type. The larger the inner clearance or diameter of washout hole, the greater was the secondary flow rate. Without washout holes, the flow behind the impeller resulted in convection. The radial flow through the washout holes of the impeller was conserved in the radial as well as in the axial direction behind the impeller. The increase in the secondary flow reduced the net pump efficiency. Simple PTV was successful in quantifying the flow in the space behind the impeller. The results verified the hypothesis that the flow behind the impeller was theoretically Couette along the circumferential direction. The convection flow observed behind the impeller agreed with the reports of other researchers. Simple PTV was effective in understanding the fluid dynamics to help improve the compact, efficient, and biocompatible centrifugal blood pump for safe clinical applications.

  17. Design and evaluation of osmotic pump-based controlled release system of Ambroxol Hydrochloride.

    PubMed

    Cheng, Xiongkai; Sun, Min; Gao, Yan; Cao, Fengliang; Zhai, Guangxi

    2011-08-01

    The purpose of the present study was to design and evaluate an osmotic pump-based drug delivery system for controlling the release of Ambroxol Hydrochloride (Amb). Citric acid, lactose and polyethylene glycol 6000 (PEG 6000) were employed as osmotic agents. Surelease EC containing polyethylene glycol 400 (PEG 400) controlling the membrane porosity was used as semi-permeable membrane. The formulation of tablet core was optimized by orthogonal design and evaluated by weighted mark method. The influences of the amount of PEG 400 and membrane thickness on Amb release were investigated. The optimal osmotic pump tablet (OPT) was evaluated in different release media and at different stirring rates. The major release power confirmed was osmotic pressure. The release of Amb from OPT was verified at a rate of approximately zero-order, and cumulative release percentage at 12?h was 92.6%. The relative bioavailability of Amb OPT in rabbits relative to the commercial sustained capsule was 109.6%. Our results showed that Amb OPT could be a practical preparation with a good prospect.

  18. Atomistic study of a nanometer-scale pump based on the thermal ratchet concept

    NASA Astrophysics Data System (ADS)

    Oyarzua, Elton; Walther, J. H.; Zambrano, Harvey

    2015-11-01

    In this study, a novel concept of nanoscale pump fabricated using Carbon Nanotubes (CNTs) is presented. The development of nanofluidic systems provides unprecedented possibilities for the control of biology and chemistry at the molecular level with potential applications in low energy cost devices, novel medical tools, and a new generation of sensors. CNTs offer a number of attractive features for the fabrication of fluidic nanodevices including fast flow, useful electronic and thermal properties, high mechanical strength and biocompatibility. Therefore, the transport of liquids in CNTs is now of great interest in nanofluidics. Thermophoresis is the phenomenon observed when a mixture of two or more types of motile objects experience a force induced by a thermal gradient and the different types of objects respond to it differently, inducing a motion and segregation of the objects. Using molecular dynamics simulations, we explore the possibility to design thermophoretic pumping devices fabricated of CNTs for water transport in nanoconduits. The design of the nanopumps is based on the concept of the Feynman-Smoluchowski ratchet. We aknowledge partial support from Fondecyt project 11130559 and Redoc udec.

  19. Analysis on pressure characteristics of pump turbine guide bearing rotating sump based on VOF model

    NASA Astrophysics Data System (ADS)

    Zhai, L. M.; Yao, Z.; Huang, Q. S.; Xiao, Y. X.; Wang, Z. W.

    2013-12-01

    With the technology of Computational Fluid Dynamics (CFD), this paper conducts a 3D numerical simulation for the oil and gas flow field in the Pump turbine guide bearing rotating sump. VOF model is adopted in this simulation. This study calculates distribution of the oil-air phase and characteristics of the pressure. The influence of sump rotating speed, oil level and oil viscosity on the pressure at the inlet of oil-immersion plate are discussed. The results demonstrate that the static pressure at the inlet is roughly proportional to oil level. Too low level may result in the separation between lubrication oil and supply hole on the oil-immersion plate, which then disables the oil supply. The static pressure at the inlet increases parabola as the sump rotating speed increases. To ensure the supply pressure, the unit is not suitable for long time operation under low rotating speed. The temperature-viscosity effect of the lubricant oil has little influence on the oil pressure at the supply hole. This paper provides a theoretical base for the safe design and operation of the pump turbine rotating sump, and offers the inlet boundary condition for the analysis of the oil film dynamic characteristics of the turbine guide bearing.

  20. Soliton-based pump-seed synchronization for few-cycle OPCPA.

    PubMed

    Teisset, C; Ishii, N; Fuji, T; Metzger, T; Köhler, S; Holzwarth, R; Baltuska, A; Zheltikov, A; Krausz, F

    2005-08-22

    We demonstrate a significant simplification of the scheme for few-cycle Optical Parametric Chirped Pulse Amplification (OPCPA) which results in the elimination of a picosecond's master oscillator and electronic synchronization loops. A fraction of a broadband seed pulse centered at 760 nm from a 70-MHz Ti:sapphire oscillator was frequency-shifted in a photonic crystal fiber to enable synchronized seeding of a picosecond's Nd:YAG pump laser. The seed radiation at 1064 nm is produced in the soliton regime which makes it inherently more intense and stable in comparison with other methods of frequency conversion. The remaining fraction of the Ti:sapphire output is amplified with a FWHM bandwidth of 250 nm in a single timing-jitter-free OPCPA stage. Our work opens up the exciting possibility to use sub-picosecond's pump pulses from highly efficient Yb-based amplifiers for jitter-less parametric amplification of carrier-envelope phase stabilized pulses from Ti:sapphire oscillators.

  1. A high carrier injection terahertz quantum cascade laser based on indirectly pumped scheme

    SciTech Connect

    Razavipour, S. G. Xu, C.; Wasilewski, Z. R.; Ban, D.; Dupont, E.; Laframboise, S. R.; Chan, C. W. I.; Hu, Q.

    2014-01-27

    A Terahertz quantum cascade laser with a rather high injection coupling strength based on an indirectly pumped scheme is designed and experimentally implemented. To effectively suppress leakage current, the chosen quantum cascade module of the device is based on a five-well GaAs/Al{sub 0.25}Ga{sub 0.75}As structure. The device lases up to 151 K with a lasing frequency of 2.67 THz. This study shows that the effect of higher energy states in carrier transport and the long-range tunnel coupling between states that belong to non-neighbouring modules have to be considered in quantum design of structures with a narrow injector barrier. Moreover, the effect of interface roughness scattering between the lasing states on threshold current is crucial.

  2. Continuously pumping and reactivating gas pump

    DOEpatents

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

    Apparatus for continuous pumping using cycling cryopumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels that 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 independant 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.

  3. Continuously pumping and reactivating gas pump

    DOEpatents

    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.

  4. Progress and challenges in electrically pumped GaN-based VCSELs

    NASA Astrophysics Data System (ADS)

    Haglund, A.; Hashemi, E.; Bengtsson, J.; Gustavsson, J.; Stattin, M.; Calciati, M.; Goano, M.

    2016-04-01

    ABSTRACT The Vertical-Cavity Surface-Emitting Laser (VCSEL) is an established optical source in short-distance optical communication links, computer mice and tailored infrared power heating systems. Its low power consumption, easy integration into two-dimensional arrays, and low-cost manufacturing also make this type of semiconductor laser suitable for application in areas such as high-resolution printing, medical applications, and general lighting. However, these applications require emission wavelengths in the blue-UV instead of the established infrared regime, which can be achieved by using GaN-based instead of GaAs-based materials. The development of GaN-based VCSELs is challenging, but during recent years several groups have managed to demonstrate electrically pumped GaN-based VCSELs with close to 1 mW of optical output power and threshold current densities between 3-16 kA/cm2. The performance is limited by challenges such as achieving high-reflectivity mirrors, vertical and lateral carrier confinement, efficient lateral current spreading, accurate cavity length control and lateral optical mode confinement. This paper summarizes different strategies to solve these issues in electrically pumped GaN-VCSELs together with state-of-the-art results. We will highlight our work on combined transverse current and optical mode confinement, where we show that many structures used for current confinement result in unintentionally optically anti-guided resonators. Such resonators can have a very high optical loss, which easily doubles the threshold gain for lasing. We will also present an alternative to the use of distributed Bragg reflectors as high-reflectivity mirrors, namely TiO2/air high contrast gratings (HCGs). Fabricated HCGs of this type show a high reflectivity (>95%) over a 25 nm wavelength span.

  5. Towards loss compensated and lasing terahertz metamaterials based on optically pumped graphene.

    PubMed

    Weis, P; Garcia-Pomar, J L; Rahm, M

    2014-04-07

    We evidence by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. We calculate the complex conductivity of graphene under optical pumping and determine the proper conditions for terahertz amplification in single layer graphene. It is shown that amplification in graphene occurs up to room temperature for moderate pump intensities at telecommunication wavelength λ = 1.5 μm. Furthermore, we investigate the coupling between a plasmonic split ring resonator (SRR) metamaterial and optically pumped graphene at a temperature T = 77 K and a pump intensity I = 300 mW/mm(2). We find that the loss of a SRR metamaterial can be compensated by optically stimulated amplification in graphene. Moreover, we show that a hybrid material consisting of asymmetric split-ring resonators and optically pumped graphene can emit coherent THz radiation at minimum output power levels of 60 nW/mm(2).

  6. Thermal effect of diode-pumped solid state lasers based on composite crystals

    NASA Astrophysics Data System (ADS)

    Hao, Ming-ming; Lu, Guo-guang; Zhu, Hong-bo; Huang, Yun; En, Yun-fei

    2013-12-01

    Thermal effect of diode-pumped solid-state lasers (DPSSL) based on YAP/Tm:YAP composite crystal is studied by using of finite element method (FEM). It is found that the peak temperature in a composite rod decreases to less than 80% of that in a non-composite crystal. Thermal stress of composite rod is obviously reduced to less than 70% comparing with non-composite crystal. It is also demonstrated that length of thermal lens unchanged with increasing of un-doped crystal length, which means that beam quality of composite laser wouldn't be improved by non-composite crystal. Therefore, it is concluded that using composite crystal would benefit for the properties of temperature and heat stress while insignificance for beam quality of DPSSL.

  7. Constructing a model-based software monitor for the insulin pump behavior.

    PubMed

    Babamir, Seyed Morteza

    2012-04-01

    Modern medical systems undertaking the task of surveillance of patients are safety-critical systems steered by software. Such systems will bring man's life into hazard if they fail to meet patients' requirements; so, adequate reliability of the algorithms and computations used by software of such systems is a matter of concern. The environment of a medical safety-critical system consisting of a patient has safety requirements that should be satisfied by the system. A safety requirement is the one that if it is violated, the system environment will be subject to severe risk. An effective method to verify the algorithms and computations used by software of such systems against safety requirements is to keep the software under surveillance at run-time. This paper aims to present a model-based method to construct a run-time monitor for a safety-critical medical system called Continuous Infusion Insulin Pump (CIIP).

  8. Validation of a PC based program for single stage absorption heat pump

    SciTech Connect

    Zaltash, A.; Ally, M.R.

    1991-09-01

    An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

  9. Validation of a PC based program for single stage absorption heat pump. Final report

    SciTech Connect

    Zaltash, A.; Ally, M.R.

    1991-09-01

    An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

  10. The optimization of low specific speed centrifugal pump based on incomplete sensitivities

    NASA Astrophysics Data System (ADS)

    Zhang, R. H.; Zheng, K.; Yao, L. H.; Shi, F. X.

    2012-11-01

    In this research, the optimization method for low specific speed centrifugal pump impeller based on incomplete sensitivities was proposed. The main feature of the algorithm is that it avoids solving the flow field repeatedly in one optimization cycle in finite difference method and it avoids solving the adjoint equation in adjoint method. The blade meridional plan is considered as constant, and the blade camber line was parameterize by Taylor function. The coefficients in the Taylor function were taken as the control variable. The moment acting on the blade was considered as the objective function. With the incomplete sensitivities we can get the gradient of the objective function with respect to the control variable easily, and the blade shape can be renewed according to the inverse direction of the gradient. We will find the optimum design when the objective function is minimized. The computational cost is greatly reduced. The calculation cases show that the proposed theory and method is rotational.

  11. The Combination of Micro Diaphragm Pumps and Flow Sensors for Single Stroke Based Liquid Flow Control.

    PubMed

    Jenke, Christoph; Pallejà Rubio, Jaume; Kibler, Sebastian; Häfner, Johannes; Richter, Martin; Kutter, Christoph

    2017-04-03

    With the combination of micropumps and flow sensors, highly accurate and secure closed-loop controlled micro dosing systems for liquids are possible. Implementing a single stroke based control mode with piezoelectrically driven micro diaphragm pumps can provide a solution for dosing of volumes down to nanoliters or variable average flow rates in the range of nL/min to μL/min. However, sensor technologies feature a yet undetermined accuracy for measuring highly pulsatile micropump flow. Two miniaturizable in-line sensor types providing electrical readout-differential pressure based flow sensors and thermal calorimetric flow sensors-are evaluated for their suitability of combining them with mircopumps. Single stroke based calibration of the sensors was carried out with a new method, comparing displacement volumes and sensor flow volumes. Limitations of accuracy and performance for single stroke based flow control are described. Results showed that besides particle robustness of sensors, controlling resistive and capacitive damping are key aspects for setting up reproducible and reliable liquid dosing systems. Depending on the required average flow or defined volume, dosing systems with an accuracy of better than 5% for the differential pressure based sensor and better than 6.5% for the thermal calorimeter were achieved.

  12. PUMP CONSTRUCTION

    DOEpatents

    Strickland, G.; Horn, F.L.; White, H.T.

    1960-09-27

    A pump which utilizes the fluid being pumped through it as its lubricating fluid is described. This is achieved by means of an improved bearing construction in a pump of the enclosed or canned rotor type. At the outlet end of the pump, adjacent to an impeller mechanism, there is a bypass which conveys some of the pumped fluid to a chamber at the inlet end of the pump. After this chamber becomes full, the pumped fluid passes through fixed orifices in the top of the chamber and exerts a thrust on the inlet end of the pump rotor. Lubrication of the rotor shaft is accomplished by passing the pumped fluid through a bypass at the outlet end of the rotor shaft. This bypass conveys Pumped fluid to a cooling means and then to grooves on the surface of the rotor shait, thus lubricating the shaft.

  13. Industrial Pumps

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A flow inducer is a device that increases the pump intake capacity of a Worthington Centrifugal pump. It lifts the suction pressure sufficiently for the rotating main impeller of the centrifugal pump to operate efficiently at higher fluid intake levels. The concept derives from 1960's NASA technology which was advanced by Worthington Pump Division. The pumps are used to recirculate wood molasses, a highly viscous substance.

  14. A biomolecular detection method based on charge pumping in a nanogap embedded field-effect-transistor biosensor

    NASA Astrophysics Data System (ADS)

    Kim, Sungho; Ahn, Jae-Hyuk; Park, Tae Jung; Lee, Sang Yup; Choi, Yang-Kyu

    2009-06-01

    A unique direct electrical detection method of biomolecules, charge pumping, was demonstrated using a nanogap embedded field-effect-transistor (FET). With aid of a charge pumping method, sensitivity can fall below the 1 ng/ml concentration regime in antigen-antibody binding of an avian influenza case. Biomolecules immobilized in the nanogap are mainly responsible for the acute changes of the interface trap density due to modulation of the energy level of the trap. This finding is supported by a numerical simulation. The proposed detection method for biomolecules using a nanogap embedded FET represents a foundation for a chip-based biosensor capable of high sensitivity.

  15. Municipal water-based heat pump heating and/or cooling systems: Findings and recommendations. Final report

    SciTech Connect

    Bloomquist, R.G.; Wegman, S.

    1998-04-01

    The purpose of the present work was to determine if existing heat pump systems based on municipal water systems meet existing water quality standards, to analyze water that has passed through a heat pump or heat exchanger to determine if corrosion products can be detected, to determine residual chlorine levels in municipal waters on the inlet as well as the outlet side of such installations, to analyses for bacterial contaminants and/or regrowth due to the presence of a heat pump or heat exchanger, to develop and suggest criteria for system design and construction, to provide recommendations and specifications for material and fluid selection, and to develop model rules and regulations for the installation, operation, and monitoring of new and existing systems. In addition, the Washington State University (WSU) has evaluated availability of computer models that would allow for water system mapping, water quality modeling and system operation.

  16. GAS-PHASE AND PARTICULATE EMISSIONS DURING APPLICATION OF A WATER-BASED CLEANER WITH A HAND-PUMP SPRAYER

    EPA Science Inventory

    The paper gives results of tests in a controlled environment test room to measure concentrations of 2-butoxyethanol and particles during application of a cleaner to realistic surfaces (counter tops, glass, walls). (NOTE: Users of water-based cleaners applied with hand-pump spray...

  17. [Research on flow characteristics in a non-blade centrifugal blood pump based on CFD technology].

    PubMed

    Cheng, Yunzhang; Luo, Binhai; Wu, Wenquan; Jiang, Lei

    2010-10-01

    The problem of thrombus and hemolysis in blood pump has always been an important topic to study in the development of the blood pump. Numbers of research results show that it is the complicated flow and the high shear stress of the mechanical movement that result in the thrombus and hemolysis. In this study, with the cooperation of Shanghai Children's Medical Center, we have used computational fluid dynamics (CFD) commercial software FLUENT to compute and analyze the flow characteristics in a non-blade centrifugal blood pump. The results figure out that this pump has a reasonable flow distribution and the shear stress distribution is under the critical broken state of red blood cell; meanwhile, there is less thrombus and hemolysis in this pump. So it is in the foreground for clinical use.

  18. Silicon-Based Chemical Motors: An Efficient Pump for Triggering and Guiding Fluid Motion Using Visible Light

    PubMed Central

    2015-01-01

    We report a simple yet highly efficient chemical motor that can be controlled with visible light. The motor made from a noble metal and doped silicon acts as a pump, which is driven through a light-activated catalytic reaction process. We show that the actuation is based on electro-osmosis with the electric field generated by chemical reactions at the metal and silicon surfaces, whereas the contribution of diffusio-osmosis to the actuation is negligible. Surprisingly, the pump can be operated using water as fuel. This is possible because of the large ζ-potential of silicon, which makes the electro-osmotic fluid motion sizable even though the electric field generated by the reaction is weak. The electro-hydrodynamic process is greatly amplified with the addition of reactive species, such as hydrogen peroxide, which generates higher electric fields. Another remarkable finding is the tunability of silicon-based pumps. That is, it is possible to control the speed of the fluid with light. We take advantage of this property to manipulate the spatial distribution of colloidal microparticles in the liquid and to pattern colloidal microparticle structures at specific locations on a wafer surface. Silicon-based pumps hold great promise for controlled mass transport in fluids. PMID:26349036

  19. Silicon-Based Chemical Motors: An Efficient Pump for Triggering and Guiding Fluid Motion Using Visible Light.

    PubMed

    Esplandiu, Maria J; Farniya, Ali Afshar; Bachtold, Adrian

    2015-11-24

    We report a simple yet highly efficient chemical motor that can be controlled with visible light. The motor made from a noble metal and doped silicon acts as a pump, which is driven through a light-activated catalytic reaction process. We show that the actuation is based on electro-osmosis with the electric field generated by chemical reactions at the metal and silicon surfaces, whereas the contribution of diffusio-osmosis to the actuation is negligible. Surprisingly, the pump can be operated using water as fuel. This is possible because of the large ζ-potential of silicon, which makes the electro-osmotic fluid motion sizable even though the electric field generated by the reaction is weak. The electro-hydrodynamic process is greatly amplified with the addition of reactive species, such as hydrogen peroxide, which generates higher electric fields. Another remarkable finding is the tunability of silicon-based pumps. That is, it is possible to control the speed of the fluid with light. We take advantage of this property to manipulate the spatial distribution of colloidal microparticles in the liquid and to pattern colloidal microparticle structures at specific locations on a wafer surface. Silicon-based pumps hold great promise for controlled mass transport in fluids.

  20. Particle size distribution of aerosols sprayed from household hand-pump sprays containing fluorine-based and silicone-based compounds.

    PubMed

    Kawakami, Tsuyoshi; Isama, Kazuo; Ikarashi, Yoshiaki

    2015-01-01

    Japan has published safety guideline on waterproof aerosol sprays. Furthermore, the Aerosol Industry Association of Japan has adopted voluntary regulations on waterproof aerosol sprays. Aerosol particles of diameter less than 10 µm are considered as "fine particles". In order to avoid acute lung injury, this size fraction should account for less than 0.6% of the sprayed aerosol particles. In contrast, the particle size distribution of aerosols released by hand-pump sprays containing fluorine-based or silicone-based compounds have not been investigated in Japan. Thus, the present study investigated the aerosol particle size distribution of 16 household hand-pump sprays. In 4 samples, the ratio of fine particles in aerosols exceeded 0.6%. This study confirmed that several hand-pump sprays available in the Japanese market can spray fine particles. Since the hand-pump sprays use water as a solvent and their ingredients may be more hydrophilic than those of aerosol sprays, the concepts related to the safety of aerosol-sprays do not apply to the hand pump sprays. Therefore, it may be required for the hand-pump spray to develop a suitable method for evaluating the toxicity and to establish the safety guideline.

  1. Performance studies of Cryocooler based cryosorption pumps with indigenous activated carbons for fusion applications

    NASA Astrophysics Data System (ADS)

    Kasthurirengan, S.; Vivek, G. A.; Verma, Ravi; Behera, Upendra; Udgata, Swarup; Gangradey, Ranjana

    2017-02-01

    Cryosorption pumps are the only solution for pumping helium and hydrogen in fusion systems, due to their high pumping speeds and suitability in harsh environments. Their development requires the right Activated Carbons (ACs) and suitable adhesives to bind them to metallic panels with liquid helium (LHe) flow channels. However, their performance evaluation will require large quantities of LHe. Alternatively, these pumps can be built with small size panels adhered with ACs and cooled by a cryocooler. The paper describes the development of a cryopump using a commercial cryocooler (Sumitomo RDK415D), with 1.5W@4.2 K, integrated with small size AC panel mounted on 2nd stage, with the 1st stage acting as radiation shield. Under no load, the cryopump reaches the ultimate pressure of 2.1E-7 mbar. The pump is built using panels with different indigenously developed ACs such as granules, pellets, ACF-FK2 and activated carbon of knitted IPR cloth. We present the experimental results of pumping speeds for gases such as nitrogen, argon and helium using the procedures outlined by American Vacuum Society (AVS). These studies will enable to arrive at the right ACs and adhesives for the development of large scale cryosorption pumps with liquid helium flow.

  2. Towards loss compensated and lasing terahertz metamaterials based on optically pumped graphene

    NASA Astrophysics Data System (ADS)

    Weis, P.; Garcia-Pomar, J. L.; Rahm, M.

    2014-04-01

    It is evidenced by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. In a first step, the complex conductivity of graphene under optical pumping is calculated and the proper conditions for terahertz amplification in single layer graphene are determined. It is shown that amplification in graphene occurs for temperatures up to room temperature and for moderate pump intensities when pumped at a telecommunication wavelength $\\lambda=1.5~\\mathrm{\\mu m}$. Furthermore, the amplification properties of graphene are evaluated and discussed at a temperature as low as $T=77~\\mathrm{K}$ and a pump intensity $I=300~\\mathrm{mW/mm^2}$ to investigate the coupling between graphene and a plasmonic split ring resonator (SRR) metamaterial. The contributions of ohmic and dielectric loss mechanisms are studied by full wave simulations. As a result, it is found that the loss of a split-ring resonator metamaterial can be compensated by optically stimulated amplification in graphene. Moreover, it is shown that a hybrid material consisting of asymmetric split-ring resonators and optically pumped graphene can exceed the laser threshold condition and can emit coherent THz radiation at minimum output power levels of $6 0~\\mathrm{nW/mm^2}$. The use of optically pumped graphene is well suited for loss compensation in THz metamaterials and paves the way to new kinds of coherent THz sources.

  3. [Numerical assessment of impeller features of centrifugal blood pump based on fast hemolysis approximation model].

    PubMed

    Shou, Chen; Guo, Yongjun; Su, Lei; Li, Yongqian

    2014-12-01

    The impeller profile, which is one of the most important factors, determines the creation of shear stress which leads to blood hemolysis in the internal flow of centrifugal blood pump. The investigation of the internal flow field in centrifugal blood pump and the estimation of the hemolysis within different impeller profiles will provide information to improve the performance of centrifugal blood pump. The SST kappa-omega with low Reynolds correction was used in our laboratory to study the internal flow fields for four kinds of impellers of centrifugal blood pump. The flow fields included distributions of pressure field, velocity field and shear stress field. In addition, a fast numerical hemolysis approximation was adopted to calculate the normalized index of hemolysis (NIH). The results indicated that the pressure field distribution in all kinds of blood pump were reasonable, but for the log spiral impeller pump, the vortex and backflow were much lower than those of the other pumps, and the high shear stress zone was just about 0.004%, and the NIH was 0.0089.

  4. Development of a pump-turbine runner based on multiobjective optimization

    NASA Astrophysics Data System (ADS)

    Xuhe, W.; Baoshan, Z.; Lei, T.; Jie, Z.; Shuliang, C.

    2014-03-01

    As a key component of reversible pump-turbine unit, pump-turbine runner rotates at pump or turbine direction according to the demand of power grid, so higher efficiencies under both operating modes have great importance for energy saving. In the present paper, a multiobjective optimization design strategy, which includes 3D inverse design method, CFD calculations, response surface method (RSM) and multiobjective genetic algorithm (MOGA), is introduced to develop a model pump-turbine runner for middle-high head pumped storage plant. Parameters that controlling blade shape, such as blade loading and blade lean angle at high pressure side are chosen as input parameters, while runner efficiencies under both pump and turbine modes are selected as objective functions. In order to validate the availability of the optimization design system, one runner configuration from Pareto front is manufactured for experimental research. Test results show that the highest unit efficiency is 91.0% under turbine mode and 90.8% under pump mode for the designed runner, of which prototype efficiencies are 93.88% and 93.27% respectively. Viscous CFD calculations for full passage model are also conducted, which aim at finding out the hydraulic improvement from internal flow analyses.

  5. PV Array Driven Adjustable Speed Drive for a Lunar Base Heat Pump

    NASA Technical Reports Server (NTRS)

    Domijan, Alexander, Jr.; Buchh, Tariq Aslam

    1995-01-01

    A study of various aspects of Adjustable Speed Drives (ASD) is presented. A summary of the relative merits of different ASD systems presently in vogue is discussed. The advantages of using microcomputer based ASDs is now widely understood and accepted. Of the three most popular drive systems, namely the Induction Motor Drive, Switched Reluctance Motor Drive and Brushless DC Motor Drive, any one may be chosen. The choice would depend on the nature of the application and its requirements. The suitability of the above mentioned drive systems for a photovoltaic array driven ASD for an aerospace application are discussed. The discussion is based on the experience of the authors, various researchers and industry. In chapter 2 a PV array power supply scheme has been proposed, this scheme will have an enhanced reliability in addition to the other known advantages of the case where a stand alone PV array is feeding the heat pump. In chapter 3 the results of computer simulation of PV array driven induction motor drive system have been included. A discussion on these preliminary simulation results have also been included in this chapter. Chapter 4 includes a brief discussion on various control techniques for three phase induction motors. A discussion on different power devices and their various performance characteristics is given in Chapter 5.

  6. Improved Potency of Indole-Based NorA Efflux Pump Inhibitors: From Serendipity toward Rational Design and Development.

    PubMed

    Buonerba, Federica; Lepri, Susan; Goracci, Laura; Schindler, Bryan D; Seo, Susan M; Kaatz, Glenn W; Cruciani, Gabriele

    2017-01-12

    The NorA efflux pump is a potential drug target for reversal of resistance to selected antibacterial agents, and recently we described indole-based inhibitor candidates. Herein we report a second class of inhibitors derived from them but with significant differences in shape and size. In particular, compounds 13 and 14 are very potent inhibitors in that they demonstrated the lowest IC50 values (2 μM) ever observed among all indole-based compounds we have evaluated.

  7. Evaluating Effects of Pump-Storage Water Withdrawals Using an Individual-Based Metapopulation Model of a Benthic Fish Species

    DTIC Science & Technology

    2011-04-01

    maintaining ab- undance of a native fish species, the Turquoise darter (Etheostoma inscriptum). We developed and applied an individual-based...based metapopulation model for assessing the effects of water withdrawals on a flow-dependent species, the Turquoise darter (Etheostoma inscriptum...withdrawal strategy for a municipal pump-storage reservoir and the status of the Turquoise darter over a 20-year period in the Middle Oco- nee River near

  8. Donor-based single electron pumps with tunable donor binding energy.

    PubMed

    Lansbergen, G P; Ono, Y; Fujiwara, A

    2012-02-08

    We report on single electron pumping via a tunable number of individual donors. We use a device that essentially consists of a silicon nanowire with local arsenic implantation between a set of fine gates. A temperature-dependent characterization of the pumped current allows us to extract the ionization energy of a single arsenic donor. We observe the ionization energy to be tunable by the gate electric field over a large range of energies.

  9. Hydrogen-bonding interaction of the protonated schiff base with halides in a chloride-pumping bacteriorhodopsin mutant.

    PubMed

    Shibata, Mikihiro; Ihara, Kunio; Kandori, Hideki

    2006-09-05

    Bacteriorhodopsin (BR) and halorhodopsin (HR) are light-driven proton and chloride ion pumps, respectively, in Halobacterium salinarum. The amino acid identity of these proteins is about 25%, suggesting that each has been optimized for their own functions during evolution. However, it is known that the BR mutants, D85T and D85S, can pump chloride ions. This fact implies that the Schiff base region is important in determining ionic selectivity. The X-ray crystallographic structure of D85S(Br(-)) showed the presence of a bromide ion in the Schiff base region (Facciotti, M. T., Cheung, V. S., Nguyen, D., Rouhani, S., and Glaeser, R. M. (2003) Biophys. J. 85, 451-458). In this article, we report on the study of hydrogen bonds of the Schiff base and water molecules in D85S in the absence and presence of various halides, assigning their N-D and O-D stretching vibrations in D(2)O, respectively, in low-temperature Fourier-transform infrared (FTIR) spectroscopy. We found that the hydrogen bond of the Schiff base in D85S(Cl(-)) is much stronger than that in HR, being as strong as that in wild-type BR. Similar halide dependence in D85S and in solution implies that the Schiff base forms a direct hydrogen bond with a halide, consistent with the X-ray structure. Photoisomerization causes a weakened hydrogen bond of the Schiff base, and halide dependence on the stretching frequency is lost. These spectral features are similar to those in the photocycle of proton-pumping BR, though the weakened hydrogen bond is more significant for BR. However, the spectral features of water bands in D85S are closer to chloride-pumping HR because O-D stretching vibrations of water are observed only at >2500 cm(-)(1). Unlike in BR, we did not observe strongly hydrogen-bonded water molecules for halide-pumping D85S mutants. This observation agrees with our recent hypothesis that strongly hydrogen-bonded water molecules are required for the proton-pumping activity of archaeal rhodopsins. Hydrogen

  10. Magnetocaloric pump

    NASA Technical Reports Server (NTRS)

    Brown, G. V.

    1973-01-01

    Very cold liquids and gases such as helium, neon, and nitrogen can be pumped by using magnetocaloric effect. Adiabatic magnetization and demagnetization are used to alternately heat and cool slug of pumped fluid contained in closed chamber.

  11. Heat pumps

    NASA Astrophysics Data System (ADS)

    Gilli, P. V.

    1982-11-01

    Heat pumps for residential/commercial space heating and hot tap water make use of free energy of direct or indirect solar heat and save from about 40 to about 70 percent of energy if compared to a conventional heating system with the same energy basis. In addition, the electrically driven compressor heat pump is able to substitute between 40% (bivalent alternative operation) to 100% (monovalent operation) of the fuel oil of an oilfired heating furnace. For average Central European conditions, solar space heating systems with high solar coverage factor show the following sequence of increasing cost effectiveness: pure solar systems (without heat pumps); heat pump assisted solar systems; solar assisted heat pump systems; subsoil/water heat pumps; air/water heat pumps; air/air heat pumps.

  12. Numerical analysis of the internal flow field in screw centrifugal blood pump based on CFD

    NASA Astrophysics Data System (ADS)

    Han, W.; Han, B. X.; Y Wang, H.; Shen, Z. J.

    2013-12-01

    As to the impeller blood pump, the high speed of the impeller, the local high shear force of the flow field and the flow dead region are the main reasons for blood damage. The screw centrifugal pump can effectively alleviate the problems of the high speed and the high shear stress for the impeller. The softness and non-destructiveness during the transfer process can effectively reduce the extent of the damage. By using CFD software, the characteristics of internal flow are analyzed in the screw centrifugal pump by exploring the distribution rules of the velocity, pressure and shear deformation rate of the blood when it flows through the impeller and the destructive effects of spiral blades on blood. The results show that: the design of magnetic levitation solves the sealing problems; the design of regurgitation holes solves the problem of the flow dead zone; the magnetic levitated microcirculation screw centrifugal pump can effectively avoid the vortex, turbulence and high shear forces generated while the blood is flowing through the pump. Since the distribution rules in the velocity field, pressure field and shear deformation rate of the blood in the blood pump are comparatively uniform and the gradient change is comparatively small, the blood damage is effectively reduced.

  13. Addition of cranberry to proton pump inhibitor-based triple therapy for Helicobacter pylori eradication

    PubMed Central

    Seyyedmajidi, Mohammadreza; Ahmadi, Anahita; Hajiebrahimi, Shahin; Seyedmajidi, Seyedali; Rajabikashani, Majid; Firoozabadi, Mona; Vafaeimanesh, Jamshid

    2016-01-01

    Objective: Proton pump inhibitor-based triple therapy with two antibiotics for Helicobacter pylori eradication is widely accepted, but this combination fails in a considerable number of cases. Some studies have shown that cranberry inhibits the adhesion of a wide range of microbial pathogens, including H. pylori. The aim of this study was to assess the effect of cranberry on H. pylori eradication with a standard therapy including lansoprazole, clarithromycin, and amoxicillin (LCA) in patients with peptic ulcer disease (PUD). Methods: In this study, H. pylori-positive patients with PUD were randomized into two groups: Group A: A 14-day LCA triple therapy with 30 mg lansoprazole bid, 1000 mg amoxicillin bid, and 500 mg clarithromycin bid; Group B: A 14-day 500 mg cranberry capsules bid plus LCA triple therapy. A 13C-urea breath test was performed for eradication assessment 6 weeks after the completion of the treatment. Findings: Two hundred patients (53.5% males, between 23 and 77 years, mean age ± standard deviation: 50.29 ± 17.79 years) continued treatment protocols and underwent 13C-urea breath testing. H. pylori eradication was achieved in 74% in Group A (LCA without cranberry) and 89% in Group B (LCA with cranberry) (P = 0.042). Conclusion: The addition of cranberry to LCA triple therapy for H. pylori has a higher rate of eradication than the standard regimen alone (up to 89% and significant). PMID:27843960

  14. Experimental study of heat pump thermodynamic cycles using CO2 based mixtures - Methodology and first results

    NASA Astrophysics Data System (ADS)

    Bouteiller, Paul; Terrier, Marie-France; Tobaly, Pascal

    2017-02-01

    The aim of this work is to study heat pump cycles, using CO2 based mixtures as working fluids. Since adding other chemicals to CO2 moves the critical point and generally equilibrium lines, it is expected that lower operating pressures as well as higher global efficiencies may be reached. A simple stage pure CO2 cycle is used as reference, with fixed external conditions. Two scenarios are considered: water is heated from 10 °C to 65 °C for Domestic Hot Water scenario and from 30 °C to 35 °C for Central Heating scenario. In both cases, water at the evaporator inlet is set at 7 °C to account for such outdoor temperature conditions. In order to understand the dynamic behaviour of thermodynamic cycles with mixtures, it is essential to measure the fluid circulating composition. To this end, we have developed a non intrusive method. Online optical flow cells allow the recording of infrared spectra by means of a Fourier Transform Infra Red spectrometer. A careful calibration is performed by measuring a statistically significant number of spectra for samples of known composition. Then, a statistical model is constructed to relate spectra to compositions. After calibration, compositions are obtained by recording the spectrum in few seconds, thus allowing for a dynamic analysis. This article will describe the experimental setup and the composition measurement techniques. Then a first account of results with pure CO2, and with the addition of propane or R-1234yf will be given.

  15. Study on water lubricated bearings of high speed pump based on numerical simulation

    NASA Astrophysics Data System (ADS)

    Bai, Y. X.; Kong, F. Y.; Sun, J. R.; Yuan, X.

    2016-05-01

    A method is presented for calculating and analyzing the performance of water lubricated bearing of high speed pump under different structure. In present work, six kinds of bearings in different radial clearance(C), which are 0.02, 0.04, 0.06, 0.08, 0.10and0.12 respectively, under the same minimum water film thickness, have been designed. The models are built by CREO and numerical simulated by ansys. The main content of the present work is to analyze the relationship between the pressure and the load carrying capacity with different radial clearance(C) by ansys workbench based on Fluid-Solid coupling through ansys workbench.The stress deformations of bearings are also acquired through thermal-structure coupling. From the comparing result among the numerical analysis under the six different model of water lubricated bearing, the relationship between radial clearance(C) and load carrying capacity, as well as the deformation of bearing under different radial clearance(C), are obtained. Further, results indicates that, a proper selection of radial clearance(C) is essential to enhance the bearing performance.

  16. Energy-efficient miniature-scale heat pumping based on shape memory alloys

    NASA Astrophysics Data System (ADS)

    Ossmer, Hinnerk; Wendler, Frank; Gueltig, Marcel; Lambrecht, Franziska; Miyazaki, Shuichi; Kohl, Manfred

    2016-08-01

    Cooling and thermal management comprise a major part of global energy consumption. The by far most widespread cooling technology today is vapor compression, reaching rather high efficiencies, but promoting global warming due to the use of environmentally harmful refrigerants. For widespread emerging applications using microelectronics and micro-electro-mechanical systems, thermoelectrics is the most advanced technology, which however hardly reaches coefficients of performance (COP) above 2.0. Here, we introduce a new approach for energy-efficient heat pumping using the elastocaloric effect in shape memory alloys. This development is mainly targeted at applications on miniature scales, while larger scales are envisioned by massive parallelization. Base materials are cold-rolled textured Ti49.1Ni50.5Fe0.4 foils of 30 μm thickness showing an adiabatic temperature change of +20/-16 K upon superelastic loading/unloading. Different demonstrator layouts consisting of mechanically coupled bridge structures with large surface-to-volume ratios are developed allowing for control by a single actuator as well as work recovery. Heat transfer times are in the order of 1 s, being orders of magnitude faster than for bulk geometries. Thus, first demonstrators achieve values of specific heating and cooling power of 4.5 and 2.9 W g-1, respectively. A maximum temperature difference of 9.4 K between heat source and sink is reached within 2 min. Corresponding COP on the device level are 4.9 (heating) and 3.1 (cooling).

  17. Nature's pumps

    NASA Astrophysics Data System (ADS)

    Vogel, Steven

    1994-10-01

    Although diverse in both form and function, the fluid-forcing devices in organisms have many of the capabilities and limitations of pumps of human design. Nature's pumps certainly look quite different from those of our technology, but all of them perform the same task. The author examines a few of these with an eye toward technological parallels and the two functional classes -- positive-displacement pumps and fluid-dynamic pumps.

  18. ELECTROMAGNETIC PUMP

    DOEpatents

    Pulley, O.O.

    1954-08-17

    This patent reiates to electromagnetic pumps for electricity-conducting fluids and, in particular, describes several modifications for a linear conduction type electromagnetic interaction pump. The invention resides in passing the return conductor for the current traversing the fiuid in the duct back through the gap in the iron circuit of the pump. Both the maximum allowable pressure and the efficiency of a linear conduction electromagnetic pump are increased by incorporation of the present invention.

  19. Estimating Pump Blockage

    NASA Technical Reports Server (NTRS)

    Chung, W.; Meng, S. Y.; Meng, C. Y.

    1984-01-01

    Blockage predicted for all components including inducers, impellers and diffusers. Pump performance predicted by semiempirical method shows excellent agreement with test results in Space Shuttle main-engine highpressure fuel turbopump. Comparisons of pump efficiency show equally good agreement of calculated values with experimental ones. Method improves current estimation methods based solely on subjective engineering judgment.

  20. Accuracy of a new patch pump based on a microelectromechanical system (MEMS) compared to other commercially available insulin pumps: results of the first in vitro and in vivo studies.

    PubMed

    Borot, Sophie; Franc, Sylvia; Cristante, Justine; Penfornis, Alfred; Benhamou, Pierre-Yves; Guerci, Bruno; Hanaire, Hélène; Renard, Eric; Reznik, Yves; Simon, Chantal; Charpentier, Guillaume

    2014-11-01

    The JewelPUMP™ (JP) is a new patch pump based on a microelectromechanical system that operates without any plunger. The study aimed to evaluate the infusion accuracy of the JP in vitro and in vivo. For the in vitro studies, commercially available pumps meeting the ISO standard were compared to the JP: the MiniMed® Paradigm® 712 (MP), Accu-Chek® Combo (AC), OmniPod® (OP), Animas® Vibe™ (AN). Pump accuracy was measured over 24 hours using a continuous microweighing method, at 0.1 and 1 IU/h basal rates. The occlusion alarm threshold was measured after a catheter occlusion. The JP, filled with physiological serum, was then tested in 13 patients with type 1 diabetes simultaneously with their own pump for 2 days. The weight difference was used to calculate the infused insulin volume. The JP showed reduced absolute median error rate in vitro over a 15-minute observation window compared to other pumps (1 IU/h): ±1.02% (JP) vs ±1.60% (AN), ±1.66% (AC), ±2.22% (MP), and ±4.63% (OP), P < .0001. But there was no difference over 24 hours. At 0.5 IU/h, the JP was able to detect an occlusion earlier than other pumps: 21 (19; 25) minutes vs 90 (85; 95), 58 (42; 74), and 143 (132; 218) minutes (AN, AC, MP), P < .05 vs AN and MP. In patients, the 24-hour flow error was not significantly different between the JP and usual pumps (-2.2 ± 5.6% vs -0.37 ± 4.0%, P = .25). The JP was found to be easier to wear than conventional pumps. The JP is more precise over a short time period, more sensitive to catheter occlusion, well accepted by patients, and consequently, of potential interest for a closed-loop insulin delivery system.

  1. Preload-based Starling-like control of rotary blood pumps: An in-vitro evaluation.

    PubMed

    Mansouri, Mahdi; Gregory, Shaun D; Salamonsen, Robert F; Lovell, Nigel H; Stevens, Michael C; Pauls, Jo P; Akmeliawati, Rini; Lim, Einly

    2017-01-01

    Due to a shortage of donor hearts, rotary left ventricular assist devices (LVADs) are used to provide mechanical circulatory support. To address the preload insensitivity of the constant speed controller (CSC) used in conventional LVADs, we developed a preload-based Starling-like controller (SLC). The SLC emulates the Starling law of the heart to maintain mean pump flow ([Formula: see text]) with respect to mean left ventricular end diastolic pressure (PLVEDm) as the feedback signal. The SLC and CSC were compared using a mock circulation loop to assess their capacity to increase cardiac output during mild exercise while avoiding ventricular suction (marked by a negative PLVEDm) and maintaining circulatory stability during blood loss and severe reductions in left ventricular contractility (LVC). The root mean squared hemodynamic deviation (RMSHD) metric was used to assess the clinical acceptability of each controller based on pre-defined hemodynamic limits. We also compared the in-silico results from our previously published paper with our in-vitro outcomes. In the exercise simulation, the SLC increased [Formula: see text] by 37%, compared to only 17% with the CSC. During blood loss, the SLC maintained a better safety margin against left ventricular suction with PLVEDm of 2.7 mmHg compared to -0.1 mmHg for CSC. A transition to reduced LVC resulted in decreased mean arterial pressure (MAP) and [Formula: see text] with CSC, whilst the SLC maintained MAP and [Formula: see text]. The results were associated with a much lower RMSHD value with SLC (70.3%) compared to CSC (225.5%), demonstrating improved capacity of the SLC to compensate for the varying cardiac demand during profound circulatory changes. In-vitro and in-silico results demonstrated similar trends to the simulated changes in patient state however the magnitude of hemodynamic changes were different, thus justifying the progression to in-vitro evaluation.

  2. Preload-based Starling-like control of rotary blood pumps: An in-vitro evaluation

    PubMed Central

    Gregory, Shaun D.; Salamonsen, Robert F.; Lovell, Nigel H.; Stevens, Michael C.; Pauls, Jo P.; Akmeliawati, Rini; Lim, Einly

    2017-01-01

    Due to a shortage of donor hearts, rotary left ventricular assist devices (LVADs) are used to provide mechanical circulatory support. To address the preload insensitivity of the constant speed controller (CSC) used in conventional LVADs, we developed a preload-based Starling-like controller (SLC). The SLC emulates the Starling law of the heart to maintain mean pump flow (QP¯) with respect to mean left ventricular end diastolic pressure (PLVEDm) as the feedback signal. The SLC and CSC were compared using a mock circulation loop to assess their capacity to increase cardiac output during mild exercise while avoiding ventricular suction (marked by a negative PLVEDm) and maintaining circulatory stability during blood loss and severe reductions in left ventricular contractility (LVC). The root mean squared hemodynamic deviation (RMSHD) metric was used to assess the clinical acceptability of each controller based on pre-defined hemodynamic limits. We also compared the in-silico results from our previously published paper with our in-vitro outcomes. In the exercise simulation, the SLC increased QP¯ by 37%, compared to only 17% with the CSC. During blood loss, the SLC maintained a better safety margin against left ventricular suction with PLVEDm of 2.7 mmHg compared to -0.1 mmHg for CSC. A transition to reduced LVC resulted in decreased mean arterial pressure (MAP) and QP¯ with CSC, whilst the SLC maintained MAP and QP¯. The results were associated with a much lower RMSHD value with SLC (70.3%) compared to CSC (225.5%), demonstrating improved capacity of the SLC to compensate for the varying cardiac demand during profound circulatory changes. In-vitro and in-silico results demonstrated similar trends to the simulated changes in patient state however the magnitude of hemodynamic changes were different, thus justifying the progression to in-vitro evaluation. PMID:28212401

  3. OSCILLATORY PUMP

    DOEpatents

    Underwood, N.

    1958-09-23

    This patent relates to a pump suitable fur pumping highly corrosive gases wherein no lubricant is needed in the pumping chamber thus eliminating possible contamination sources. The chamber contains a gas inlet and outlet in each side, with a paddle like piston suspended by a sylphon seal between these pcrts. An external arrangement causes the paddle to oscillate rapidly between the ports, alternately compressing and exhausting the gas trapped on each side of the paddle. Since the paddle does nnt touch the chamber sides at any point, no lubricant is required. This pump is useful for pumping large quantities of uranium hexafluorine.

  4. Champagne Heat Pump

    NASA Technical Reports Server (NTRS)

    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.

  5. Polarization insensitive all-optical up-conversion for ROF systems based on parallel pump FWM in a SOA.

    PubMed

    Lu, Jia; Dong, Ze; Cao, Zizheng; Chen, Lin; Wen, Shuangchun; Yu, Jianguo

    2009-04-27

    We have proposed and experimentally investigated polarization insensitive all-optical up-conversion for ROF system based on FWM in a semiconductor optical amplifier (SOA). The parallel pump is generated based on odd-order optical sidebands and carrier suppression using an external intensity modulator and a cascaded optical filter. Therefore, the two pumps are always parallel and phase locked, which makes system polarization insensitive. After FWM in a SOA and optical filtering, similar to single sideband (SSB) 40 GHz optical millimeter-wave is generated only using 10 GHz RF as local oscillator (LO). The receiver sensitivity at a BER of 10(-9) for the up-converted signals is -28.4 dBm. The power penalty for the up-converted downstream signals is smaller than 1 dBm after 20 km SSMF-28 transmission.

  6. Demodulation for hydraulic pump fault signals based on local mean decomposition and improved adaptive multiscale morphology analysis

    NASA Astrophysics Data System (ADS)

    Jiang, Wanlu; Zheng, Zhi; Zhu, Yong; Li, Yang

    2015-06-01

    Scales of IAMMA are adaptively determined by morphological features of signal, thus fault features of a hydraulic pump fault signal presented in multi-scales can be adaptively demodulated. In some coefficient range, IAMMA outperforms AMMA in demodulation ability based on the same SE, and it is less susceptible to noises than AMMA. The best performance of IAMMA with triangle SE is stronger than that of IAMMA with plat and semi-circle SE when they demodulate the same fault signal of hydraulic pump. Compared with traditional demodulation methods of HT and TKEO, IAMMA is adaptive and has stronger demodulation ability. An evaluation method based on kurtosis, power and standard deviation is proposed, by which some PFs which are rich in fault features can be selected as data source.

  7. Evaluation of 100G DP-QPSK long-haul transmission performance using second order co-pumped Raman laser based amplification.

    PubMed

    Tan, Mingming; Rosa, Paweł; Le, Son Thai; Phillips, Ian D; Harper, Paul

    2015-08-24

    We present, for the first time, a detailed investigation of the impact of second order co-propagating Raman pumping on long-haul 100G WDM DP-QPSK coherent transmission of up to 7082 km using Raman fibre laser based configurations. Signal power and noise distributions along the fibre for each pumping scheme were characterised both numerically and experimentally. Based on these pumping schemes, the Q factor penalties versus co-pump power ratios were experimentally measured and quantified. A significant Q factor penalty of up to 4.15 dB was observed after 1666 km using symmetric bidirectional pumping, compared with counter-pumping only. Our results show that whilst using co-pumping minimises the intra-cavity signal power variation and amplification noise, the Q factor penalty with co-pumping was too great for any advantage to be seen. The relative intensity noise (RIN) characteristics of the induced fibre laser and the output signal, and the intra-cavity RF spectra of the fibre laser are also presented. We attribute the Q factor degradation to RIN induced penalty due to RIN being transferred from the first order fibre laser and second order co-pump to the signal. More importantly, there were two different fibre lasing regimes contributing to the amplification. It was random distributed feedback lasing when using counter-pumping only and conventional Fabry-Perot cavity lasing when using all bidirectional pumping schemes. This also results in significantly different performances due to different laser cavity lengths for these two classes of laser.

  8. PUMP SETS NO. 5 AND NO. 4. Each pump set ...

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

    PUMP SETS NO. 5 AND NO. 4. Each pump set consists of a Worthington Pump and a General Electric motor - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  9. Numerical prediction of pressure fluctuations in a prototype pump turbine base on PANS methods

    NASA Astrophysics Data System (ADS)

    Liu, J. T.; Li, Y.; Gao, Y.; Hu, Q.; Wu, Y. L.

    2016-05-01

    Unsteady flow and pressure fluctuations within a prototypel pump turbine are numerically studied using a nonlinear Partial Averaged Navier Stokes (PANS) model. Pump turbine operating at different conditions with guide vanes opening angle 6° is simulated. Results revealed that the predictions of performance and relative peak-to-peak amplitude by PANS approach agree well with the experimental data. The amplitude of the pressure fluctuation in the vaneless space at turbine mode on a “S” curve increases with the decrease of the flow rate, and it has maximum value when it runs close to runaway line at turbine braking mode. The amplitude of the pressure fluctuation in the vaneless space at turbine braking mode on a “S” curve decreases with the reduce of the flow rate. The above high pressure fluctuations should be avoided during the design of pump turbines especially those operating at high-head condition.

  10. Optimizing wind pumps system for crop irrigation based on wind data processing

    NASA Astrophysics Data System (ADS)

    Ruiz, Fernando; Tarquis, Ana M.; Sanchez, Raúl; Garcia, Jose Luis

    2015-04-01

    Crop irrigation is a major consumer of energy that can be resolved with renewable ones, such as wind, which has experienced recent developments in the area of power generation. Therefore, wind power can play an interesting role in irrigation projects in different areas [1]. A simple methodology has been developed in previous papers for technical evaluation of windmills for irrigation water pumping [2]. This methodology can determine the feasibility of the technology and the levels of daily irrigation demand satisfied by windmills. The present work compared the possibilities of this methodology adjusting the three-hourly wind velocity to the Weibull II distribution function, without considering the time sequence [2], or processing wind data using time series analysis. The study was applied to practical cases of wind pumps for irrigation of crops, both in the outside (corn) and inside greenhouses (tomato). The analysis showed that the use of three hourly time series analysis supplied a more realistic modelling of the situation with a better optimization of the water storage tank of the wind pump facility taking into account the risk of calm periods in which the pumping is null. A factor to consider in this study is available precision of the wind sampling rate. References [1] Díaz-Méndez, R., Adnan Rasheed, M. Peillón, A. Perdigones, R. Sánchez, A.M. Tarquis, José L. García-Fernández. Wind pumps for irrigating greenhouse crops: comparison in different socio-economical frameworks. Biosystems Engineering, 128, 21-28, 2014. [2] Peillón, M., Sánchez, R., Tarquis, A.M., García, J.L. The use of wind pumps for greenhouse microirrigation: A case study for tomato in Cuba. Agricultural Water Management, 120, 107-114, 2013.

  11. Potential Coastal Pumped Hydroelectric Energy Storage Locations Identified using GIS-based Topographic Analysis

    NASA Astrophysics Data System (ADS)

    Parsons, R.; Barnhart, C. J.; Benson, S. M.

    2013-12-01

    Large-scale electrical energy storage could accommodate variable, weather dependent energy resources such as wind and solar. Pumped hydroelectric energy storage (PHS) and compressed energy storage area (CAES) have life cycle energy and financial costs that are an order of magnitude lower than conventional electrochemical storage technologies. However PHS and CAES storage technologies require specific geologic conditions. Conventional PHS requires an upper and lower reservoir separated by at least 100 m of head, but no more than 10 km in horizontal distance. Conventional PHS also impacts fresh water supplies, riparian ecosystems, and hydrologic environments. A PHS facility that uses the ocean as the lower reservoir benefits from a smaller footprint, minimal freshwater impact, and the potential to be located near off shore wind resources and population centers. Although technologically nascent, today one coastal PHS facility exists. The storage potential for coastal PHS is unknown. Can coastal PHS play a significant role in augmenting future power grids with a high faction of renewable energy supply? In this study we employ GIS-based topographic analysis to quantify the coastal PHS potential of several geographic locations, including California, Chile and Peru. We developed automated techniques that seek local topographic minima in 90 m spatial resolution shuttle radar topography mission (SRTM) digital elevation models (DEM) that satisfy the following criteria conducive to PHS: within 10 km from the sea; minimum elevation 150 m; maximum elevation 1000 m. Preliminary results suggest the global potential for coastal PHS could be very significant. For example, in northern Chile we have identified over 60 locations that satisfy the above criteria. Two of these locations could store over 10 million cubic meters of water or several GWh of energy. We plan to report a global database of candidate coastal PHS locations and to estimate their energy storage capacity.

  12. A power management system for energy harvesting and wireless sensor networks application based on a novel charge pump circuit

    NASA Astrophysics Data System (ADS)

    Aloulou, R.; De Peslouan, P.-O. Lucas; Mnif, H.; Alicalapa, F.; Luk, J. D. Lan Sun; Loulou, M.

    2016-05-01

    Energy Harvesting circuits are developed as an alternative solution to supply energy to autonomous sensor nodes in Wireless Sensor Networks. In this context, this paper presents a micro-power management system for multi energy sources based on a novel design of charge pump circuit to allow the total autonomy of self-powered sensors. This work proposes a low-voltage and high performance charge pump (CP) suitable for implementation in standard complementary metal oxide semiconductor (CMOS) technologies. The CP design was implemented using Cadence Virtuoso with AMS 0.35μm CMOS technology parameters. Its active area is 0.112 mm2. Consistent results were obtained between the measured findings of the chip testing and the simulation results. The circuit can operate with an 800 mV supply and generate a boosted output voltage of 2.835 V with 1 MHz as frequency.

  13. Yb fiber laser pumped mid-IR source based on difference frequency generation and its application to ammonia detection

    NASA Technical Reports Server (NTRS)

    Matsuoka, N.; Yamaguchi, S.; Nanri, K.; Fujioka, T.; Richter, D.; Tittel, F. K.

    2001-01-01

    A Yb fiber laser pumped cw narrow-linewidth tunable mid-IR source based on a difference frequency generation (DFG) in a periodically poled LiNbO3 (PPLN) crystal for trace gas detection was demonstrated. A high power Yb fiber laser and a distributed feedback (DFB) laser diode were used as DFG pump sources. This source generated mid-IR at 3 microns with a powers of 2.5 microW and a spectral linewidth of less than 30 MHz. A frequency tuning range of 300 GHz (10 cm-1) was obtained by varying the current and temperature of the DFB laser diode. A high-resolution NH3 absorption Doppler-broadened spectrum at 3295.4 cm-1 (3.0345 microns) was obtained at a cell pressure of 27 Pa from which a detection sensitivity of 24 ppm m was estimated.

  14. Ti:sapphire-pumped deep-infrared femtosecond optical parametric oscillator based on CdSiP2.

    PubMed

    Ramaiah-Badarla, V; Chaitanya Kumar, S; Esteban-Martin, A; Devi, K; Zawilski, K T; Schunemann, P G; Ebrahim-Zadeh, M

    2016-04-15

    We report on a femtosecond optical parametric oscillator (OPO) for the deep-infrared (deep-IR) based on the Kerr-lens-mode-locked Ti:sapphire laser as the pump source. By deploying a novel cascaded intracavity arrangement, comprising a femtosecond OPO based on the nonlinear crystal, CdSiP2, synchronously pumped internal to a MgO:PPLN femtosecond OPO, we have generated broadly tunable radiation across 5958-8117 nm using rapid static cavity delay tuning, with a maximum power of 64 μW at 6791 nm, limited by the absorption in mirror substrates as well as polarization-dependent intracavity losses. The deep-IR idler power exhibits excellent passive stability of better than 1.1% rms over 2 h, with a spectral bandwidth as large as ∼650 nm at ∼6800 nm. The demonstrated concept is generic and can be similarly deployed in other operating time scales and wavelength regions, also using different laser pump sources and nonlinear materials.

  15. A field comparison of BTEX mass flow rates based on integral pumping tests and point scale measurements.

    PubMed

    Dietze, Michael; Dietrich, Peter

    2011-03-25

    Measuring contaminant flow rates at control cross sections is the most accurate method to evaluate natural attenuation processes in the saturated subsurface. In most instances, point scale measurement is the method of choice due to practical reasons and cost factors. However, at many field sites, the monitoring network is too sparse for a reliable estimation of contaminant and groundwater flow rates. Therefore, integral pumping tests have been developed as an alternative. In this study, we compare mass flow rates obtained by integral pumping test results and point scale data. We compare results of both methods with regard to uncertainties due to estimation errors and mass flow estimations based on two different point scale networks. The differences between benzene and groundwater flow rate estimates resulting from point scale samples and integral pumping tests were 6.44% and 6.97%, respectively, demonstrating the applicability of both methods at the site. Point scale-based data, especially with use of cost efficient Direct-Push technique, can be applied to show the contaminant distribution at a site and may be followed by a denser point scale network or an integral method. Nevertheless, a combination of both methods decreases uncertainties.

  16. Normetex Pump Alternatives Study

    SciTech Connect

    Clark, Elliot A.

    2013-04-25

    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

  17. Thermally biased AC electrokinetic pumping effect for lab-on-a-chip based delivery of biofluids.

    PubMed

    Yuan, Quan; Wu, Jie

    2013-02-01

    One major motivation for microfluidic research is to develop point of care diagnostic tools, which often demands a solution for chip-scale pumping that is of low cost, small size and light weight. Electrokinetics has been extensively studied for disposable pumping since only electrodes are needed to induce microflows. However, it encounters difficulties with conductive biofluids because of the associated high salt content. In electrokinetic pumps, electrodes are in direct contact with fluid, so high salt content will compress the electric double layer that is essential to electroosmostic flows. Alternating current electrothermal (ACET) effect is the only electrokinetic method found viable for biofluid actuation. While high frequency (>10 kHz) operation can suppress electrochemical reactions, electrical potential that could be applied over biofluids is still limited within several volts due to risk of electrolysis or impedance mismatch. Since ACET flow velocity has a quartic dependence on the voltage, ACET flows would be rather slow if electric field alone is used for actuation. This work studies the effect of a thermal bias on enhancing AC electrokinetic pumping. With proper imposition of external thermal gradients, significant improvement in flow velocity has been demonstrated by numerical simulation and preliminary experiments. Both showed that with 4 V(rms) at 100 kHz, flow velocity increased from ~10 μm/s when there was no thermal biasing to ~112 μm/s when a heat flux was applied.

  18. Cavitation performance prediction of mixed-flow pump based on CFD

    NASA Astrophysics Data System (ADS)

    Yang, F.; Liu, C.; Tang, F. P.

    2012-11-01

    The computational fluid dynamics (CFD) method is used to investigate the three-dimensional cavitation flow fields in a mixed-flow pump with high specific speed. In the numerical modeling, the homogeneous mixture model and Navier-Stokes equation with RNG k-ɛ turbulence model are employed. At the best efficiency condition, the cavitation location on the impeller blades and the distribution situation of vapor volume fraction were analyzed, as well as the performance curve between the pump's NPSHA and efficiency were predicted. The results show that, the cavitation directly affects the pressure distribution on impeller blade surfaces, and also results in change of the pump external characteristic. Under the primary cavitation condition, Water vapors first accumulate on the suction surface of blade's leading edge, which is close to the tip. With the decrease of inlet total pressure, the cavitation region extended towards the trailing edge and water vapor fraction volume become larger gradually. When cavitation is serious, water vapors mainly accumulate on the suction surface of blade's trailing edge. The prediction curve has the same trend as the practical curve, which can reveal the mixed-flow pump cavitation within the static characteristics.

  19. MEMS based pumped liquid cooling systems for micro/nano spacecraft thermal control

    NASA Technical Reports Server (NTRS)

    Birur, G. C.; Shakkottai, P.; Sur, T. W.

    2000-01-01

    The electronic and other payload power densities in future micro/nano spacecraft are expected to exceed 25 Watts/cm(sup 2) and require advanced thermal control concepts and technologies to keep their payload within allowable temperature limits. This paper presents background on the need for pumped liquid cooling systems for future micro/nano spacecraft and results from this ongoing experimental investigation.

  20. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis.

    PubMed

    Wang, Guorong; Zhong, Lin; He, Xia; Lei, Zhongqing; Hu, Gang; Li, Rong; Wang, Yunhai

    2015-01-01

    The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality. An optimal spring stiffness parameter of 14.6 N/mm was obtained, and the volumetric efficiency of the pumping valve increased by 4‰ in comparison to results obtained with the original spring stiffness of 10.09N/mm. The experimental results indicated that the mathematical model and FSI method could provide an effective approach for the subsequent improvement of valve reliability, volumetric efficiency and lifespan.

  1. Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis

    PubMed Central

    Wang, Guorong; Zhong, Lin; He, Xia; Lei, Zhongqing; Hu, Gang; Li, Rong; Wang, Yunhai

    2015-01-01

    The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality. An optimal spring stiffness parameter of 14.6 N/mm was obtained, and the volumetric efficiency of the pumping valve increased by 4‰ in comparison to results obtained with the original spring stiffness of 10.09N/mm. The experimental results indicated that the mathematical model and FSI method could provide an effective approach for the subsequent improvement of valve reliability, volumetric efficiency and lifespan. PMID:26488290

  2. Study on vibration characteristics of the shaft system for a dredging pump based on FEM

    NASA Astrophysics Data System (ADS)

    Zhai, L. M.; Qin, L.; Liu, C. Y.; Liu, X.; He, L. Y.; He, Y.; Wang, Z. W.

    2012-11-01

    The dynamic characteristics of the shaft system for a dredging pump were studied with the Finite Element Method (FEM) by SAMCEF ROTOR. At first, the influence of the fluid-solid coupling interaction of mud water and impeller, water sealing and pump shaft on the lateral critical speeds were analyzed. The results indicated that the mud water must be taken into consideration, while the water sealing need not to. Then the effects of radial and thrust rolling bearings on the lateral critical speeds were discussed, which shows that the radial bearing close to the impeller has greatest impact on the 1st order critical speed. At last, the upper and lower limits of the critical speeds of lateral, axial and torsional vibration were calculated. The rated speed of the dredging pump was far less than the predicted critical speed, which can ensure the safe operation of the unit. Each vibration mode is also shown in this paper. This dynamic analysis method offers some reference value on the research of vibration and stability of the shaft system in dredging pump.

  3. Intermittent chaos and sliding window symbol sequence statistics-based early fault diagnosis for hydraulic pump on hydraulic tube tester

    NASA Astrophysics Data System (ADS)

    Zhao, Zhen; Jia, Mingxing; Wang, Fuli; Wang, Shu

    2009-07-01

    To ensure the safety, continuity of production, make a reasonable maintenance plan, save the cost of maintenance for hydraulic tube tester, it is needed to quickly identify an assignable cause of a fault. This paper is concerned with early fault diagnosis of hydraulic pump which are the heart of hydraulic tube tester. Considering that the signal of the hydraulic pump early fault is a periodic weak signal, an intermittent chaos, sliding window symbol sequence statistics-based method is proposed to detect the early fault of one single piston loose shoes of hydraulic pump on a hydraulic tube tester. The approach presented is based on the insight that the phase transition of chaos oscillator, for example, the Duffing oscillator, is very sensitive to a periodic weak signal having little angular frequency difference with the referential signal of the oscillator. While observing the intermittent chaos phenomenon through figure is not easy for computer, a sliding window symbol sequence statistics is developed to realize real-time computer observation of this phenomenon. Rather more, this paper takes a trick to decreasing the computational complexity of the sliding window symbol sequence statistics method, also analyzes the influences of different window size, depths of the symbol tree on the information entropy. At last, a control limit is introduced to realize automatic early fault alarm. The resultant approach is experimented with data simulated from an AMESim model of hydraulic tube tester. The results indicate that the proposed approach is capable of detecting the signal of hydraulic pump early fault on hydraulic tube tester.

  4. Microfluidic pumping, routing and metering by contactless metal-based electro-osmosis.

    PubMed

    Fu, Xiaotong; Mavrogiannis, Nicholas; Doria, Steven; Gagnon, Zachary

    2015-09-07

    Over the past decade, many microfluidic platforms for fluid processing have been developed in order to perform on-chip fluidic manipulations. Many of these methods, however, require expensive and bulky external supporting equipment, which are not typically applicable for microsystems requiring portability. We have developed a new type of portable contactless metal electro-osmotic micropump capable of on-chip fluid pumping, routing and metering. The pump operates using two pairs of gallium metal electrodes, which are activated using an external voltage source, and separated from a main flow channel by a thin micron-scale PDMS membrane. The thin contactless membrane allows for field penetration and electro-osmotic (EO) flow within the microchannel, but eliminates electrode damage and sample contamination commonly associated with traditional DC electro-osmotic pumps that utilize electrodes in direct contact with the working fluid. The maximum flow rates and pressures generated by the pump using DI water as a working buffer are 10 nL min(-1) and 30 Pa, respectively. With our current design, the maximum operational conductivity where fluid flow is observed is 0.1 mS cm(-1). Due to the small size and simple fabrication procedure, multiple micropump units can be integrated into a single microfluidic device for automated on-chip routing and sample metering applications. We experimentally demonstrated the ability to quantify micropump electro-osmotic flowrate and pressure as a function of applied voltage, and developed a mathematical model capable of predicting the performance of a contactless micropump for a given external load and internal hydrodynamic microchannel resistance. Finally, we showed that by activating specific pumps within a microchannel network, our micropumps are capable of routing microchannel fluid flow and generating plugs of solute.

  5. Impulse pumping modelling and simulation

    NASA Astrophysics Data System (ADS)

    Pierre, B.; Gudmundsson, J. S.

    2010-08-01

    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.

  6. Prospects for diode-pumped alkali-atom-based hollow-core photonic-crystal fiber lasers.

    PubMed

    Sintov, Yoav; Malka, Dror; Zalevsky, Zeev

    2014-08-15

    By employing large hollow-core Kagome fiber in a double-clad configuration, the performance of a potentially rubidium vapor-based fiber laser is explored. The absorbed power and laser efficiency versus pump power are calculated utilizing a simple laser model. Our results show that a Kagome-based high-power fiber laser is feasible provided that the value of the collisional fine-structure mixing rate will be elevated by increasing the ambient temperature or by increasing the helium pressure.

  7. Qualification Testing of Laser Diode Pump Arrays for a Space-Based 2-micron Coherent Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, Nathaniel R.; Barnes, Bruce W.; Singh, Upendra N.; Kavaya, Michael J.

    2007-01-01

    The 2-micron thulium and holmium-based lasers being considered as the transmitter source for space-based coherent Doppler lidar require high power laser diode pump arrays operating in a long pulse regime of about 1 msec. Operating laser diode arrays over such long pulses drastically impact their useful lifetime due to the excessive localized heating and substantial pulse-to-pulse thermal cycling of their active regions. This paper describes the long pulse performance of laser diode arrays and their critical thermal characteristics. A viable approach is then offered that allows for determining the optimum operational parameters leading to the maximum attainable lifetime.

  8. Hydraulic optimization of a double-channel pump's impeller based on multi-objective genetic algorithm

    NASA Astrophysics Data System (ADS)

    Zhao, Binjuan; Wang, Yu; Chen, Huilong; Qiu, Jing; Hou, Duohua

    2015-03-01

    Computational fluid dynamics (CFD) can give a lot of potentially very useful information for hydraulic optimization design of pumps, however, it cannot directly state what kind of modification should be made to improve such hydrodynamic performance. In this paper, a more convenient and effective approach is proposed by combined using of CFD, multi-objective genetic algorithm (MOGA) and artificial neural networks (ANN) for a double-channel pump's impeller, with maximum head and efficiency set as optimization objectives, four key geometrical parameters including inlet diameter, outlet diameter, exit width and midline wrap angle chosen as optimization parameters. Firstly, a multi-fidelity fitness assignment system in which fitness of impellers serving as training and comparison samples for ANN is evaluated by CFD, meanwhile fitness of impellers generated by MOGA is evaluated by ANN, is established and dramatically reduces the computational expense. Then, a modified MOGA optimization process, in which selection is performed independently in two sub-populations according to two optimization objectives, crossover and mutation is performed afterword in the merged population, is developed to ensure the global optimal solution to be found. Finally, Pareto optimal frontier is found after 500 steps of iterations, and two optimal design schemes are chosen according to the design requirements. The preliminary and optimal design schemes are compared, and the comparing results show that hydraulic performances of both pumps 1 and 2 are improved, with the head and efficiency of pump 1 increased by 5.7% and 5.2%, respectively in the design working conditions, meanwhile shaft power decreased in all working conditions, the head and efficiency of pump 2 increased by 11.7% and 5.9%, respectively while shaft power increased by 5.5%. Inner flow field analyses also show that the backflow phenomenon significantly diminishes at the entrance of the optimal impellers 1 and 2, both the area of

  9. High power tunable femtosecond ultraviolet laser source based on an Yb-fiber-laser pumped optical parametric oscillator.

    PubMed

    Gu, Chenglin; Hu, Minglie; Fan, Jintao; Song, Youjian; Liu, Bowen; Chai, Lu; Wang, Chingyue; Reid, Derryck T

    2015-03-09

    We report a high average power tunable 51 MHz femtosecond ultraviolet (UV) laser source based on an intra-cavity sum frequency mixing optical parametric oscillator (OPO) pumped by a fiber laser. The UV laser is generated by sum frequency generation (SFG) between the second harmonic of a mode-locked Yb-fiber laser and the signal of the OPO. A non-collinear configuration is used in the SFG to compensate the group velocity mismatch, and to increase the SFG conversion efficiency dramatically. Tunable ultraviolet pulses within the wavelength range from 385 to 400 nm have been produced with a maximum average power of 402 mW and a pulse width of 286 fs at 2 W Yb-fiber laser pump, corresponding to 20.1% near-infrared to UV conversion efficiency at 387 nm. To our knowledge, this is the first demonstration of tunable femtosecond UV pulse generation from a fiber laser pumped OPO, and is also the highest average power tunable UV femtosecond pulses from an OPO.

  10. In situ monitoring of atmospheric nitrous acid based on multi-pumping flow system and liquid waveguide capillary cell.

    PubMed

    Liu, Yuhan; Lu, Keding; Dong, Huabin; Li, Xin; Cheng, Peng; Zou, Qi; Wu, Yusheng; Liu, Xingang; Zhang, Yuanhang

    2016-05-01

    In the last four decades, various techniques including spectroscopic, wet chemical and mass spectrometric methods, have been developed and applied for the detection of ambient nitrous acid (HONO). We developed a HONO detection system based on long path photometry which consists of three independent modules i.e., sampling module, fluid propulsion module and detection module. In the propulsion module, solenoid pumps are applied. With solenoid pumps the pulsed flow can be computer controlled both in terms of pump stroke volume and pulse frequency, which enables the attainment of a very stable flow rate. In the detection module, a customized Liquid Waveguide Capillary Cell (LWCC) is used. The customized LWCC pre-sets the optical fiber in-coupling with the liquid wave guide, providing the option of fast startup and easy maintenance of the absorption photometry. In summer 2014, our system was deployed in a comprehensive campaign at a rural site in the North China Plain. More than one month of high quality HONO data spanning from the limit of detection to 5ppb were collected. Intercomparison of our system with another established system from Forschungszentrum Juelich is presented and discussed. In conclusion, our instrument achieved a detection limit of 10pptV within 2min and a measurement uncertainty of 7%, which is well suited for investigation of the HONO budget from urban to rural conditions in China.

  11. High-power, fiber-laser-pumped, picosecond optical parametric oscillator based on MgO:sPPLT.

    PubMed

    Kumar, S Chaitanya; Ebrahim-Zadeh, M

    2011-12-19

    We report a stable, high-power, mid-infrared synchronously-pumped optical parametric oscillator (SPOPO) based on MgO:sPPLT, pumped by a 1064 nm, picosecond Yb-fiber laser operating at a repetition rate of 81.1 MHz. The singly resonant SPOPO is tunable over 1531-1642 nm (111 nm) in the near-infrared signal and 3022-3488 nm (466 nm) in the mid-infrared idler, providing a total tuning range of 577 nm. Careful optimization of output coupling results in a signal output power as high as 4.3 W at 1593 nm and a mid-infrared idler power of 2 W at 3204 nm for 13.4 W of pump power at a total extraction efficiency of 47%. The SPOPO can be operated near room temperature, down to 30 °C, and exhibits passive peak-to-peak power stability better than 8.6% at 1568 nm (signal) and 8.2% at 3310 nm (idler) over 13 hours at full power. The output signal pulses have duration of 17.5 ps, with a FWHM spectral bandwidth of 1.4 nm centered at 1568 nm.

  12. Heat loss analysis-based design of a 12 MW wind power generator module having an HTS flux pump exciter

    NASA Astrophysics Data System (ADS)

    Sung, Hae-Jin; Go, Byeong-Soo; Jiang, Zhenan; Park, Minwon; Yu, In-Keun

    2016-11-01

    The development of an effective high-temperature superconducting (HTS) generator is currently a research focus; however, the reduction of heat loss of a large-scale HTS generator is a challenge. This study deals with a heat loss analysis-based design of a 12 MW wind power generator module having an HTS flux pump exciter. The generator module consists of an HTS rotor of the generator and an HTS flux pump exciter. The specifications of the module were described, and the detailed configuration of the module was illustrated. For the heat loss analysis of the module, the excitation loss of the flux pump exciter, eddy current loss of all of the structures in the module, radiation loss, and conduction loss of an HTS coil supporter were assessed using a 3D finite elements method program. In the case of the conduction loss, different types of the supporters were compared to find out the supporter of the lowest conduction loss in the module. The heat loss analysis results of the module were reflected in the design of the generator module and discussed in detail. The results will be applied to the design of large-scale superconducting generators for wind turbines including a cooling system.

  13. Widely tunable all-fiber optical parametric oscillator based on a photonic crystal fiber pumped by a picosecond ytterbium-doped fiber laser.

    PubMed

    Zhang, Lei; Yang, Sigang; Wang, Xiaojian; Gou, Doudou; Li, Xiangliang; Chen, Hongwei; Chen, Minghua; Xie, Shizhong

    2013-11-15

    We report on a fully fiber-integrated widely tunable optical parametric oscillator based on a photonic crystal fiber pumped by a picosecond ytterbium-doped fiber laser. The output wavelength of the oscillator can be continuously tuned from 898 to 1047 nm and from 1086 to 1277 nm, which is as wide as 340 nm. In particular, a larger Raman gain peak is simultaneously observed when the pump wavelength is far from the zero-dispersion wavelength in the normal-dispersion regime. The bandwidth of the output of the oscillator can be tuned by slightly adjusting the pump power.

  14. Axial Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George Arthur (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1997-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  15. Pumping system

    SciTech Connect

    Kime, J.A.

    1987-05-19

    This patent describes a gas-oil production system for pumping formation fluid in a well through a tubing string within which a down hole pump connects to a hydraulic stroking device through a rod string providing the pump including a plunger reciprocally driven by the hydraulic stroking device toward an upper terminal position during a plunger upstroke. The rod string normally supports the weight of a column of fluid and toward a lower terminal position at the end of a plunger downstroke during which the weight of the column fluid is normally transferred to the tubing string through fluid within the pump. The method for detecting when the well is pumped off comprises: supplying working fluid to the hydraulic stroking device to raise the hydraulic stroking device and thereby move the plunger from the lower terminal position to the upper terminal position; and removing the working fluid at a controlled rate from the hydraulic stroking device.

  16. Ferroelectric Pump

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    2000-01-01

    A ferroelectric pump has one or more variable volume pumping chambers internal to a housing. Each chamber has at least one wall comprising a dome shaped internally prestressed ferroelectric actuator having a curvature and a dome height that varies with an electric voltage applied between an inside and outside surface of the actuator. A pumped medium flows into and out of each pumping chamber in response to displacement of the ferroelectric actuator. The ferroelectric actuator is mounted within each wall and isolates each ferroelectric actuator from the pumped medium, supplies a path for voltage to be applied to each ferroelectric actuator, and provides for positive containment of each ferroelectric actuator while allowing displacement of the entirety of each ferroelectric actuator in response to the applied voltage.

  17. RENEWABLE LIQUID GETTERING PUMP

    DOEpatents

    Batzer, T.H.

    1962-08-21

    A method and structure were developed for pumping gases by simple absorption into a liquid gettering material. The invention comprises means ror continuously pumping a liquid getterrng material from a reservoir to the top of a generally vertical surface disposed in a vacuum pumping chamber to receive gaseous and other particles in the liquid gettering material which continuously flows downward over the vertical suiface. Means are provided for continuous removal, degassing, and return of a portion of the liquid gettering material from the reservoir connected with collectrng means at the base of the generally vertical plate. (AEC)

  18. Space rocket engine on the base of the reactor-pumped laser for the interplanetary flights and earth orbital applications

    NASA Astrophysics Data System (ADS)

    Gulevich, Andrey V.; Dyachenko, Peter P.; Kukharchuk, Oleg F.; Zrodnikov, Anatoly V.

    2000-01-01

    In this report the concept of vehicle-based reactor-laser engine for long time interplanetary and interorbital (LEO to GEO) flights is proposed. Reactor-pumped lasers offer the perspective way to create on the base of modern nuclear and lasers technologies the low mass and high energy density, repetitively pulsed vehicle-based laser of average power 100 kW. Nowadays the efficiency of nuclear-to-optical energy conversion reached the value of 2-3%. The demo model of reactor-pumped laser facility is under construction in Institute for Physics and Power Engineering (Obninsk, Russia). It enable us to hope that using high power laser on board of the vehicle could make the effective space laser engine possible. Such engine may provide the high specific impulse ~1000-2000 s with the thrust up to 10-100 n. Some calculation results of the characteristics of vehicle-based reactor-laser thermal engine concept are also presented. .

  19. High-power efficient cw and pulsed lasers based on bulk Yb : KYW crystals with end diode pumping

    SciTech Connect

    Kim, G H; Yang, G H; Lee, D S; Kulik, Alexander V; Sall', E G; Chizhov, S A; Yashin, V E; Kang, U

    2012-04-30

    End-diode-pumped lasers based on one and two Yb : KYW crystals operating in cw and Q-switched regimes, as well as in the regime of mode-locking, are studied. The single-crystal laser generated stable ultrashort (shorter than 100 fs) laser pulses at wavelengths of 1035 and 1043 nm with an average power exceeding 1 W. The average output power of the two-crystal laser exceeded 18 W in the cw regime and 16 W in the Q-switched regime with a slope efficiency exceeding 30%.

  20. Use of expert judgment in the development and evaluation of risk-based inservice testing strategies for pumps and valves

    SciTech Connect

    McAllister, W.J.; Perdue, R.K.; Balkey, K.R.; Closky, N.B.

    1996-12-01

    This paper describes a rigorous approach for quantitatively evaluating inservice testing effectiveness that evolved from two pilot plant studies. These studies prototyped methodologies for designing and selecting inservice testing (IST) strategies in a manner structured to insure that the targeted components will perform their required safety functions while minimizing life cycle inservice testing costs. The paper concentrates on the use of expert judgment in developing test effectiveness measures that move risk-based methods beyond ranking to optimization of plant IST programs. Selected results for check valves and pumps are shown to illustrate the practical significance of the approach.

  1. Sub-Doppler spectroscopy based on optical pumping and transit relaxation of atoms in a thin gas cell

    NASA Astrophysics Data System (ADS)

    Izmailov, Azad Ch.

    2007-06-01

    The paper is the review of methods, achievements, and possibilities of the recently elaborated and well tested high-resolution laser spectroscopy based on sub-Doppler absorption and polarization resonances (on centers of quantum transitions), which arise because of the optical pumping and specific transit relaxation of atoms (molecules) in a thin cell with a rarefied gas. Theoretical basis of this spectroscopy is presented. Experimental technique and results on the record of the sub-Doppler spectral structure of Cs and Rb atoms and on the frequency stabilization of diode lasers by given spectroscopy methods are discussed.

  2. Plasmonic Bowtie Antenna Nanolaser

    DTIC Science & Technology

    2014-05-06

    the cubic of the wavelength in vacuum and can operate at room temperature under electrical injection in continuous-wave mode. Our team has... injection in continuous-wave mode. Our team has successfully achieved this goal using the semiconductor-metal core-shell design. A secondary goal is to...temperature continuous wave lasing in deep-subwavelength metallic cavities under electrical injection , Physical Review B, (01 2012): 41301. doi: 10.1103

  3. Submersible pump

    SciTech Connect

    Todd, D. B.

    1985-08-27

    A method and apparatus for using a submersible pump to lift reservoir fluids in a well while having the tubing/casing annulus isolated from the produced fluids. The apparatus allows the submersible pump to be positioned above the annular packoff device. The apparatus comprises an outer shield that encloses the pump and can be attached to the production tubing. The lower end of the shield attaches to a short tubing section that seals with the annular packoff device or a receptacle above the annular packoff device.

  4. System optimization of a heat-switch-based electrocaloric heat pump

    NASA Astrophysics Data System (ADS)

    Smullin, Sylvia J.; Wang, Yunda; Schwartz, David E.

    2015-08-01

    Realization of the potential of electrocaloric heat pumps includes consideration of not only material properties but also device characteristics and cycle operation. We present detailed models and analysis that elucidate the key parameters for performance optimization. We show that the temperature lift, cooling power, and efficiency of a system driven by heat switches depend on system operating conditions and the combined thermal properties of both the heat switches and the electrocaloric capacitor. We show experimental results that validate the models and draw conclusions about building high-performance systems.

  5. Evidence-based assessment of proton-pump inhibitors in Helicobacter pylori eradication: A systematic review

    PubMed Central

    Nagaraja, Vinayak; Eslick, Guy D

    2014-01-01

    Peptic ulcer disease continues to be issue especially due to its high prevalence in the developing world. Helicobacter pylori (H. pylori) infection associated duodenal ulcers should undergo eradication therapy. There are many regimens offered for H. pylori eradication which include triple, quadruple, or sequential therapy regimens. The central aim of this systematic review is to evaluate the evidence for H. pylori therapy from a meta-analytical outlook. The consequence of the dose, type of proton-pump inhibitor, and the length of the treatment will be debated. The most important risk factor for eradication failure is resistance to clarithromycin and metronidazole. PMID:25356018

  6. Aspartate-histidine interaction in the retinal schiff base counterion of the light-driven proton pump of Exiguobacterium sibiricum.

    PubMed

    Balashov, S P; Petrovskaya, L E; Lukashev, E P; Imasheva, E S; Dioumaev, A K; Wang, J M; Sychev, S V; Dolgikh, D A; Rubin, A B; Kirpichnikov, M P; Lanyi, J K

    2012-07-24

    One of the distinctive features of eubacterial retinal-based proton pumps, proteorhodopsins, xanthorhodopsin, and others, is hydrogen bonding of the key aspartate residue, the counterion to the retinal Schiff base, to a histidine. We describe properties of the recently found eubacterium proton pump from Exiguobacterium sibiricum (named ESR) expressed in Escherichia coli, especially features that depend on Asp-His interaction, the protonation state of the key aspartate, Asp85, and its ability to accept a proton from the Schiff base during the photocycle. Proton pumping by liposomes and E. coli cells containing ESR occurs in a broad pH range above pH 4.5. Large light-induced pH changes indicate that ESR is a potent proton pump. Replacement of His57 with methionine or asparagine strongly affects the pH-dependent properties of ESR. In the H57M mutant, a dramatic decrease in the quantum yield of chromophore fluorescence emission and a 45 nm blue shift of the absorption maximum with an increase in the pH from 5 to 8 indicate deprotonation of the counterion with a pK(a) of 6.3, which is also the pK(a) at which the M intermediate is observed in the photocycle of the protein solubilized in detergent [dodecyl maltoside (DDM)]. This is in contrast with the case for the wild-type protein, for which the same experiments show that the major fraction of Asp85 is deprotonated at pH >3 and that it protonates only at low pH, with a pK(a) of 2.3. The M intermediate in the wild-type photocycle accumulates only at high pH, with an apparent pK(a) of 9, via deprotonation of a residue interacting with Asp85, presumably His57. In liposomes reconstituted with ESR, the pK(a) values for M formation and spectral shifts are 2-3 pH units lower than in DDM. The distinctively different pH dependencies of the protonation of Asp85 and the accumulation of the M intermediate in the wild-type protein versus the H57M mutant indicate that there is strong Asp-His interaction, which substantially lowers

  7. Prognostics of slurry pumps based on a moving-average wear degradation index and a general sequential Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Tse, Peter W.

    2015-05-01

    Slurry pumps are commonly used in oil-sand mining for pumping mixtures of abrasive liquids and solids. These operations cause constant wear of slurry pump impellers, which results in the breakdown of the slurry pumps. This paper develops a prognostic method for estimating remaining useful life of slurry pump impellers. First, a moving-average wear degradation index is proposed to assess the performance degradation of the slurry pump impeller. Secondly, the state space model of the proposed health index is constructed. A general sequential Monte Carlo method is employed to derive the parameters of the state space model. The remaining useful life of the slurry pump impeller is estimated by extrapolating the established state space model to a specified alert threshold. Data collected from an industrial oil sand pump were used to validate the developed method. The results show that the accuracy of the developed method improves as more data become available.

  8. [Design push-pull osmotic pump tablets of famotidine based on an expert system for the formulation design of osmotic pump of poor water-soluble drug].

    PubMed

    Zhang, Zhi-Hong; Jin, Jie; Zhang, Hong-Wu; Xin, Wei; Jia, Guo-Bin; Wu, Wen-Fang; Pan, Wei-San

    2011-01-01

    The purpose of this study is to design push-pull osmotic pump (PPOP) tablets of famotidine using the expert system for the formulation design of osmotic pump of poor water-soluble drug which had been established by the authors. Firstly, the parameters which were requisite of the system input were obtained from literatures and experimental tests. Then the parameters were input into the system, and the program was run. The system displayed the designed formulations sequential. Finally, famotidine PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. It was found out that the target formulation of famotidine PPOP which could release for 24 hours was obtained in a very short period. Meanwhile, the practicability of the established expert system was proved.

  9. OPTICAL RECORDING AND COMMUNICATION: Mismatch of the pump parameters of coupled chaotic lasers and the signal recovery errors in the data transmission scheme based on these lasers

    NASA Astrophysics Data System (ADS)

    Ledenev, V. I.

    2004-08-01

    The pulse characteristics of a periodically pumped chaotic CO2 laser are calculated numerically. The errors of the encoding-function recovery in the data transmission link based on two optically coupled chaotic CO2 lasers are studied depending on the amplitude mismatch and pump modulation frequencies. It is shown that the recovery error is minimal when the pump parameters of a transmitter and a receiver are identical. It is also shown that the mismatch of the pump amplitudes of the receiver and transmitter affects the recovery error much weaker than the mismatch of their periods. The dependences of the recovery error on the signal modulation degree are found. It is found that the shape of the recovered encoding function is determined by the type of a deviated parameter.

  10. ION PUMP

    DOEpatents

    Milleron, N.

    1961-01-01

    An ion pump and pumping method are given for low vacuum pressures in which gases introduced into a pumping cavity are ionized and thereafter directed and accelerated into a quantity of liquid gettering metal where they are absorbed. In the preferred embodiment the metal is disposed as a liquid pool upon one electrode of a Phillips ion gauge type pump. Means are provided for continuously and remotely withdrawing and degassing the gettering metal. The liquid gettering metal may be heated if desired, although various combinations of gallium, indium, tin, bismuth, and lead, the preferred metals, have very low melting points. A background pressure of evaporated gettering metal may be provided by means of a resistance heated refractory metal wick protruding from the surface of the pcol of gettering metal.

  11. Electrokinetic pump

    DOEpatents

    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.

  12. Stochastic pumping of ions based on colored noise in bacterial channels under acidic stress

    NASA Astrophysics Data System (ADS)

    López, M. Lidón; Queralt-Martín, María; Alcaraz, Antonio

    2016-07-01

    Fluctuation-driven ion transport can be obtained in bacterial channels with the aid of different types of colored noise including the biologically relevant Lorentzian one. Using the electrochemical rectification of the channel current as a ratchet mechanism we observe transport of ions up to their concentration gradient under conditions similar to that met in vivo, namely moderate pH gradients and asymmetrically charged lipid membranes. We find that depending on the direction of the concentration gradient the channel can pump either cations or anions from the diluted side to the concentrated one. We discuss the possible relevance of this phenomenon for the pH homeostasis of bacterial cells.Fluctuation-driven ion transport can be obtained in bacterial channels with the aid of different types of colored noise including the biologically relevant Lorentzian one. Using the electrochemical rectification of the channel current as a ratchet mechanism we observe transport of ions up to their concentration gradient under conditions similar to that met in vivo, namely moderate pH gradients and asymmetrically charged lipid membranes. We find that depending on the direction of the concentration gradient the channel can pump either cations or anions from the diluted side to the concentrated one. We discuss the possible relevance of this phenomenon for the pH homeostasis of bacterial cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02638a

  13. Analysis of a 10 megawatt space-based solar-pumped neodymium laser system

    NASA Technical Reports Server (NTRS)

    Kurweg, U. H.

    1984-01-01

    A ten megawatt solar-pumped continuous liquid laser system for space applications is examined. It is found that a single inflatable mirror of 434 m diameter used in conjunction with a conical secondary concentrator is sufficient to side pump a liquid neodymium lasant in an annular tube of 6 m length and 1 m outer and 0.8 m inner diameter. About one fourth of intercepted radiation converging on the laser tube is absorbed and one fifth of this radiation is effective in populating the upper levels. The liquid lasant is flowed through the annular laser cavity at 1.9 m/s and is cooled via a heat exchanger and a large radiator surface comparable in size to the concentrating mirror. The power density of incident light within the lasant of approximately 68 watt/cu cm required for cw operation is exceeded in the present annular configuration. Total system weight corresponds to 20,500 kg and is thus capable of being transported to near Earth orbit by a single shuttle flight.

  14. Power flow control based solely on slow feedback loop for heart pump applications.

    PubMed

    Wang, Bob; Hu, Aiguo Patrick; Budgett, David

    2012-06-01

    This paper proposes a new control method for regulating power flow via transcutaneous energy transfer (TET) for implantable heart pumps. Previous work on power flow controller requires a fast feedback loop that needs additional switching devices and resonant capacitors to be added to the primary converter. The proposed power flow controller eliminates these additional components, and it relies solely on a slow feedback loop to directly drive the primary converter to meet the heart pump power demand and ensure zero voltage switching. A controlled change in switching frequency varies the resonant tank shorting period of a current-fed push-pull resonant converter, thus changing the magnitude of the primary resonant voltage, as well as the tuning between primary and secondary resonant tanks. The proposed controller has been implemented successfully using an analogue circuit and has reached an end-to-end power efficiency of 79.6% at 10 W with a switching frequency regulation range of 149.3 kHz to 182.2 kHz.

  15. Numerical investigation on the jet pump performance based on different turbulence models

    NASA Astrophysics Data System (ADS)

    Yang, X. L.; Long, X. P.

    2012-11-01

    This paper aims to figure out the influence of turbulence model and wall boundary condition on the simulation of performance and flow field of jet pumps. And then try to find out one combination of turbulence model and wall treatment method that gives out more accurate performance prediction and reasonable internal flow details. Six turbulence models, (namely the three k-epsilon, the standard and SST k-omega, and Reynolds stress models) and two wall treatment methods (standard wall functions and enhanced wall treatment) were involved. A jet pump model used in an experiment was chosen as the simulation prototype. The static pressure distribution along the wall and the performance data from the experiment were used as the reference data for validating with those from the simulation results. It is found that all the ten combinations agree well with the experiment data when the volumetric flow ratio is low, however, none of them could give a performance prediction with errors less than 10% under the lager flow ratio work conditions. The errors between predicted results by several combinations and the experiment data were lowered to be less than 5% under all the working conditions by adjusting the model constants.

  16. Fiber-laser-based, green-pumped, picosecond optical parametric oscillator using fan-out grating PPKTP.

    PubMed

    Chaitanya Kumar, S; Parsa, S; Ebrahim-Zadeh, M

    2016-01-01

    We report a stable, Yb-fiber-laser-based, green-pumped, picosecond optical parametric oscillator (OPO) for the near-infrared based on periodically poled potassium titanyl phosphate (PPKTP) nonlinear crystal, using fan-out grating design and operating near room temperature. The OPO is continuously tunable across 726-955 nm in the signal and 1201-1998 nm in the idler, resulting in a total signal plus idler wavelength coverage of 1026 nm by grating tuning at a fixed temperature. The device generates up to 580 mW of average power in the signal at 765 nm and 300 mW in the idler at 1338 nm, with an overall extraction efficiency of up to 52% and a pump depletion >76%. The extracted signal at 765 nm and idler at 1746 nm exhibit excellent passive power stability better than 0.5% and 0.8% rms, respectively, over 1 h with good beam quality in TEM00 mode profile. The output signal pulses have a Gaussian temporal duration of 13.2 ps, with a FWHM spectral bandwidth of 3.4 nm at 79.5 MHz repetition rate. Power scaling limitations of the OPO due to the material properties of PPKTP are studied.

  17. In vivo performance evaluation and establishment of IVIVC for osmotic pump based extended release formulation of milnacipran HCl.

    PubMed

    Parejiya, Punit B; Barot, Bhavesh S; Patel, Hetal K; Chorawala, Mehul R; Shelat, Pragna K; Shukla, Arunkumar

    2013-05-01

    The objective of the present study was to carry out a pharmacokinetics evaluation of an oral modified release formulation [Aquarius EKX 19102 SRX-2 based osmotic pump (OP)] containing highly soluble milnacipran HCl (MH) as a model drug. It was also aimed at developing an in vitro-in vivo correlation (IVIVC) model for a developed OP. In vivo plasma concentration data were obtained from six healthy male New Zealand albino rabbits after administration of immediate-release milnacipran HCl solution (IRMHSOL) and milnacipran HCl osmotic pump (MHOP). In vitro samples were analysed using an in house developed spectrophotometry method and in vivo samples were analysed using a RP-HPLC method developed by the author. A deconvolution based Level A model was attempted through a correlation of the percent in vivo input obtained through deconvolution and the percent in vitro dissolution obtained experimentally. A good correlation between the percentages dissolved vs absorbed (R(2) = 0.978) was obtained using level A correlation. Evaluation of the internal predictability of level A correlation was calculated in terms of the percent prediction error, which was found to be below 15%. In a nutshell, the success of the present study warrants further studies in patient volunteers to assess the ability of the MHOP to provide an effective therapy for depression.

  18. Direct electro-optical pumping for hybrid CdSe nanocrystal/III-nitride based nano-light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Mikulics, M.; Arango, Y. C.; Winden, A.; Adam, R.; Hardtdegen, A.; Grützmacher, D.; Plinski, E.; Gregušová, D.; Novák, J.; Kordoš, P.; Moonshiram, A.; Marso, M.; Sofer, Z.; Lüth, H.; Hardtdegen, H.

    2016-02-01

    We propose a device concept for a hybrid nanocrystal/III-nitride based nano-LED. Our approach is based on the direct electro-optical pumping of nanocrystals (secondary excitation) by electrically driven InGaN/GaN nano-LEDs as the primary excitation source. To this end, a universal hybrid optoelectronic platform was developed for a large range of optically active nano- and mesoscopic structures. The advantage of the approach is that the emission of the nanocrystals can be electrically induced without the need of contacting them. The proof of principal was demonstrated for the electro-optical pumping of CdSe nanocrystals. The nano-LEDs with a diameter of 100 nm exhibit a very low current of ˜8 nA at 5 V bias which is several orders of magnitude smaller than for those conventionally used. The leakage currents in the device layout were typically in the range of 8 pA to 20 pA/cm2 at 5 V bias. The photon-photon down conversion efficiency was determined to be 27%. Microphotoluminescence and microelectroluminescence characterization demonstrate the potential for future optoelectronics and highly secure "green" information technology applications.

  19. Fuel pump

    SciTech Connect

    Bellis, P.D.; Nesselrode, F.

    1991-04-16

    This patent describes a fuel pump. It includes: a fuel reservoir member, the fuel reservoir member being formed with fuel chambers, the chambers comprising an inlet chamber and an outlet chamber, means to supply fuel to the inlet chamber, means to deliver fuel from the outlet chamber to a point of use, the fuel reservoir member chambers also including a bypass chamber, means interconnecting the bypass chamber with the outlet chamber; the fuel pump also comprising pump means interconnecting the inlet chamber and the outlet chamber and adapted to suck fuel from the fuel supply means into the inlet chamber, through the pump means, out the outlet chamber, and to the fuel delivery means; the bypass chamber and the pump means providing two substantially separate paths of fuel flow in the fuel reservoir member, bypass plunger means normally closing off the flow of fuel through the bypass chamber one of the substantially separate paths including the fuel supply means and the fuel delivery means when the bypass plunger means is closed, the second of the substantially separate paths including the bypass chamber when the bypass plunger means is open, and all of the chambers and the interconnecting means therebetween being configured so as to create turbulence in the flow of any fuel supplied to the outlet chamber by the pump means and bypassed through the bypass chamber and the interconnecting means.

  20. Equations determine reasonable rod pump submergence depth

    SciTech Connect

    Hu Yongquan; Cai Wizhong

    1997-03-24

    A reasonable rod pump submergence depth can be calculated by combining fluid level changes with piston travel. Submergence depth is affected by the pump fill factor, reservoir fluid viscosity, rod pump type, and pumping parameters such as pump diameter, polished-rod stroke length, and pumping speed. Fluid level velocity can be obtained with an energy balance, and piston travel rate is based on the polished-rod travel. The paper describes the pump fill factor, piston travel velocity, fluid level rise, flow coefficient, reasonable submergence depth, and results from equations.

  1. Ultrafast pump-probe dynamics of iron oxide based earth pigments for applications to ancient pottery manufacture

    NASA Astrophysics Data System (ADS)

    Villafana, Tana E.; Brown, William; Warren, Warren S.; Fischer, Martin

    2015-06-01

    We demonstrate that ultrafast pump-probe microscopy provides unique dynamics for natural iron oxide and iron hydroxide earth pigments, despite their chemical similarity. First, we conducted a pump-probe spectroscopy study on heat-treated hematite (the pure red iron oxide mineral) and found the pump-probe dynamics to be temperature dependent. Second, we investigated pottery fired under known conditions and observed firing dependent pump-probe dynamics. Finally, we imaged a New World potshard from the North Carolina Museum of Art. Our results indicate that pump-probe microscopy could be a useful tool in elucidating pottery manufacture.

  2. A compact and high efficiency diode pumped green laser based on MgO doped PPLN

    NASA Astrophysics Data System (ADS)

    Zheng, X. S.; Ji, B.; Jia, F. Q.; Cai, Z. P.; Xu, H. Y.; Xu, C. Q.

    2011-11-01

    In this work, an efficient intra-cavity second harmonic generation of green laser in a periodically poled MgO doped LiNbO3 (MgO:PPLN) bulk crystal using a compact Nd:YVO4 laser as a fundamental laser source is reported. Different length, different working temperature MgO:PPLN crystals are tested and investigated in the SHG experiments. The maximum output power at 532 nm is 6.2 W at the absorbed pump power at 808 nm of 14 W, the optical to optical conversion efficiencies from 808 to 532 nm and 1064 to 532 nm are 43 and 77%, respectively, the instability in 2 hours is less than 5%.

  3. Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models: Preprint

    SciTech Connect

    Hudon, K.; Sparn, B.; Christensen, D.; Maguire, J.

    2012-02-01

    This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. Laboratory results demonstrate the efficiency of this technology under most of the conditions tested and show that differences in control schemes and design features impact the performance of the individual units. These results were used to understand current model limitations, and then to bracket the energy savings potential for HPWH technology in various US climate regions. Simulation results show that HPWHs are expected to provide significant energy savings in many climate zones when compared to other types of water heaters (up to 64%, including impact on HVAC systems).

  4. Pump-limited, 203 W, single-frequency monolithic fiber amplifier based on laser gain competition.

    PubMed

    Zeringue, Clint; Vergien, Christopher; Dajani, Iyad

    2011-03-01

    We present high power results of a Yb-doped fiber amplifier seeded with a combination of broad and single-frequency laser signals. This two-tone concept was used in conjunction with externally applied or intrinsically formed thermal gradients to demonstrate combined stimulated Brillouin scattering suppression in a copumped monolithic, polarization-maintaining (PM) fiber. Depending on the input parameters and the thermal gradient, the output power of the single-frequency signal ranged from 80 to 203 W with slope efficiencies from 70% to 80%. The 203 W amplifier was pump limited and is, to the best of our knowledge, the highest reported in the literature for monolithic, PM single-frequency fiber amplifiers.

  5. High-energy kHz mid-IR tunable PPSLT-based OPO pumped at 1064 nm

    SciTech Connect

    Gaydardzhiev, A; Chuchumishev, D; Draganov, D; Buchvarov, I

    2012-06-30

    We report a single-frequency sub-nanosecond optical parametric oscillator (OPO) based on periodically poled stoichiometric lithium tantalate (PPSLT), pumped by a 1064-nm amplified microchip laser at a repetition rate of 0.5 kHz. Using a 11-mm-long PPSLT crystal polled with three different domain periods (30.2, 30.3, 30.4 {mu}m) and changing the temperature of the crystal from 20 Degree-Sign C to 265 Degree-Sign C, we have achieved wavelength tuning between 2990 nm and 3500 nm. The high nonlinearity of the used medium and the large aperture (2 mm) ensure the maximum idler output energy of {approx}0.5 mJ in the whole tuning range, corresponding to average {approx}10.5 % idler conversion efficiency and {approx}250 mW of average power. Sub-nanosecond pulse durations have been obtained for the idler at 0.88-ns pulse duration of the pump.

  6. Influence of Rotor-Stator Interaction on Flow Stability in Centrifugal Pump Based on Energy Gradient Method

    NASA Astrophysics Data System (ADS)

    Zheng, Lu-Lu; Dou, Hua-Shu; Jiang, Wei; Chen, Xiaoping; Zhu, Zuchao; Cui, Baoling

    2016-12-01

    Numerical simulation is performed for the three-dimensional turbulent flow field in a centrifugal pump by solving the Reynolds-averaged Navier-Stokes equations and the RNG k-epsilon turbulent model. The finite volume method and the SIMPLE algorithm are employed for the solution of the system. All the parameters in the centrifugal pump at different blade angular positions are obtained by simulation. The flow structure is analyzed and the distributions of the energy gradient function K are calculated at different blade angular positions based on the energy gradient method. According to the energy gradient method, the location which has larger value of K is easier to cause instability and to be of high turbulence intensity. The result shows that the flow instability is easier to be excited nearing the tongue where the value of K is large. The unstable flow area nearing the tongue is also in agreement with the zone where the velocity decreases rapidly. The sudden variation of velocity contributes to the large value of K. The research result also indicates that the tongue has large impact only on the impeller passages passing the tongue.

  7. Charge pump-based MOSFET-only 1.5-bit pipelined ADC stage in digital CMOS technology

    NASA Astrophysics Data System (ADS)

    Singh, Anil; Agarwal, Alpana

    2016-10-01

    A simple low-power and low-area metal-oxide-semiconductor field-effect transistor-only fully differential 1.5-bit pipelined analog-to-digital converter stage is proposed and designed in Taiwan Semiconductor Manufacturing Company 0.18 μm-technology using BSIM3v3 parameters with supply voltage of 1.8 V in inexpensive digital complementary metal-oxide semiconductor (CMOS) technology. It is based on charge pump technique to achieve the desired voltage gain of 2, independent of capacitor mismatch and avoiding the need of power hungry operational amplifier-based architecture to reduce the power, Si area and cost. Various capacitances are implemented by metal-oxide semiconductor capacitors, offering compatibility with cheaper digital CMOS process in order to reduce the much required manufacturing cost.

  8. Optimizations of spin-exchange relaxation-free magnetometer based on potassium and rubidium hybrid optical pumping

    NASA Astrophysics Data System (ADS)

    Fang, Jiancheng; Wang, Tao; Zhang, Hong; Li, Yang; Zou, Sheng

    2014-12-01

    The hybrid optical pumping atomic magnetometers have not realized its theoretical sensitivity, the optimization is critical for optimal performance. The optimizations proposed in this paper are suitable for hybrid optical pumping atomic magnetometer, which contains two alkali species. To optimize the parameters, the dynamic equations of spin evolution with two alkali species were solved, whose steady-state solution is used to optimize the parameters. The demand of the power of the pump beam is large for hybrid optical pumping. Moreover, the sensitivity of the hybrid optical pumping magnetometer increases with the increase of the power density of the pump beam. The density ratio between the two alkali species is especially important for hybrid optical pumping magnetometer. A simple expression for optimizing the density ratio is proposed in this paper, which can help to determine the mole faction of the alkali atoms in fabricating the hybrid cell before the cell is sealed. The spin-exchange rate between the two alkali species is proportional to the saturated density of the alkali vapor, which is highly dependent on the temperature of the cell. Consequently, the sensitivity of the hybrid optical pumping magnetometer is dependent on the temperature of the cell. We proposed the thermal optimization of the hybrid cell for a hybrid optical pumping magnetometer, which can improve the sensitivity especially when the power of the pump beam is low. With these optimizations, a sensitivity of approximately 5 fT/Hz1/2 is achieved with gradiometer arrangement.

  9. Optimizations of spin-exchange relaxation-free magnetometer based on potassium and rubidium hybrid optical pumping

    SciTech Connect

    Fang, Jiancheng; Wang, Tao Li, Yang; Zhang, Hong; Zou, Sheng

    2014-12-15

    The hybrid optical pumping atomic magnetometers have not realized its theoretical sensitivity, the optimization is critical for optimal performance. The optimizations proposed in this paper are suitable for hybrid optical pumping atomic magnetometer, which contains two alkali species. To optimize the parameters, the dynamic equations of spin evolution with two alkali species were solved, whose steady-state solution is used to optimize the parameters. The demand of the power of the pump beam is large for hybrid optical pumping. Moreover, the sensitivity of the hybrid optical pumping magnetometer increases with the increase of the power density of the pump beam. The density ratio between the two alkali species is especially important for hybrid optical pumping magnetometer. A simple expression for optimizing the density ratio is proposed in this paper, which can help to determine the mole faction of the alkali atoms in fabricating the hybrid cell before the cell is sealed. The spin-exchange rate between the two alkali species is proportional to the saturated density of the alkali vapor, which is highly dependent on the temperature of the cell. Consequently, the sensitivity of the hybrid optical pumping magnetometer is dependent on the temperature of the cell. We proposed the thermal optimization of the hybrid cell for a hybrid optical pumping magnetometer, which can improve the sensitivity especially when the power of the pump beam is low. With these optimizations, a sensitivity of approximately 5 fT/Hz{sup 1/2} is achieved with gradiometer arrangement.

  10. Optimizations of spin-exchange relaxation-free magnetometer based on potassium and rubidium hybrid optical pumping.

    PubMed

    Fang, Jiancheng; Wang, Tao; Zhang, Hong; Li, Yang; Zou, Sheng

    2014-12-01

    The hybrid optical pumping atomic magnetometers have not realized its theoretical sensitivity, the optimization is critical for optimal performance. The optimizations proposed in this paper are suitable for hybrid optical pumping atomic magnetometer, which contains two alkali species. To optimize the parameters, the dynamic equations of spin evolution with two alkali species were solved, whose steady-state solution is used to optimize the parameters. The demand of the power of the pump beam is large for hybrid optical pumping. Moreover, the sensitivity of the hybrid optical pumping magnetometer increases with the increase of the power density of the pump beam. The density ratio between the two alkali species is especially important for hybrid optical pumping magnetometer. A simple expression for optimizing the density ratio is proposed in this paper, which can help to determine the mole faction of the alkali atoms in fabricating the hybrid cell before the cell is sealed. The spin-exchange rate between the two alkali species is proportional to the saturated density of the alkali vapor, which is highly dependent on the temperature of the cell. Consequently, the sensitivity of the hybrid optical pumping magnetometer is dependent on the temperature of the cell. We proposed the thermal optimization of the hybrid cell for a hybrid optical pumping magnetometer, which can improve the sensitivity especially when the power of the pump beam is low. With these optimizations, a sensitivity of approximately 5 fT/Hz(1/2) is achieved with gradiometer arrangement.

  11. Hemolysis in different centrifugal pumps.

    PubMed

    Kawahito, K; Nosé, Y

    1997-04-01

    Different types of centrifugal pumps cause different amounts of hemolysis based on shear stress and blood exposure time. However, the hemolytic characteristics of centrifugal pumps in each clinical condition are not always clear. We compared the hemolytic characteristics of one cone-type centrifugal pump (Medtronic BioMedicus BP-80) and 2 impeller-type centrifugal pumps (Nikkiso HMS-12 and Terumo Capiox) under experimental conditions simulating their use in cardiopulmonary bypass (CPB), extracorporeal membrane oxygenation (ECMO), and percutaneous cardiopulmonary support (PCPS) as well as their use as left ventricular assist devices (LVADs). The normalized indexes of hemolysis (NIHs; grams free plasma hemoglobin per 100 L blood pumped) during use as LVADs were not significantly different among the 3 pumps. The BP-80 pump produced almost 3-fold more hemolysis than the HMS-12 and Capiox pumps during CPB, 3- to 4-fold more hemolysis during ECMO, and 5.5-fold more hemolysis during PCPS. The 2 impeller-type centrifugal pumps will therefore cause less hemolysis under high flow, high pressure difference (as in CPB) and low flow, high pressure difference (as in ECMO and PCPS) conditions than the cone-type pump.

  12. DIFFUSION PUMP

    DOEpatents

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  13. Electrokinetic pump

    DOEpatents

    Hencken, Kenneth R.; Sartor, George B.

    2004-08-03

    An electrokinetic pump in which the porous dielectric medium of conventional electrokinetic pumps is replaced by a patterned microstructure. The patterned microstructure is fabricated by lithographic patterning and etching of a substrate and is formed by features arranged so as to create an array of microchannels. The microchannels have dimensions on the order of the pore spacing in a conventional porous dielectric medium. Embedded unitary electrodes are vapor deposited on either end of the channel structure to provide the electric field necessary for electroosmotic flow.

  14. Functional nanocrystal-based memories with extraction of nanocrystals properties by charge pumping technique

    NASA Astrophysics Data System (ADS)

    Diaz, R.; Grisolia, J.; Pecassou, B.; Shalchian, M.; BenAssayag, G.

    2013-04-01

    2D arrays of Si nanocrystals embedded in the gate oxide (⩽10 nm) of NVRAM-like transistors are synthesized by ultra-low-energy ion implantation (ULE-II). As we have shown previously, characteristics of trapping centers responsible for the memory performance such as type, depth location into the oxide, effective size and density could be obtained by using the two-level charge pumping (CP) technique performed versus frequency. It has also been demonstrated clearly that these trapping centers are the Si-NCs. However, in order to enhance the memory performances (i.e. charge retention and endurance to cycling), the synthesis of the Si-NCs must be carefully tuned, especially by adjusting the annealing conditions. In this paper, we demonstrate both that the Si-NCs are still responsible for the charge trapping while transistors are fabricated with strong NCs annealing conditions and that some memory performances recommended by the ITRS, more specifically the endurance criteria, are satisfied, with more than 106 erase/write cycles without degradation of the memory window. Therefore, our synthesis technique could provide high-performances non-volatile memories, ensuring the charge trapping in NCs.

  15. Monitoring of Building Heating and Cooling Systems Based on Geothermal Heat Pump in Galicia (Spain)

    NASA Astrophysics Data System (ADS)

    Iglesias, M.; Rodriguez, J.; Franco, D.

    2012-10-01

    In November 2009 was signed an agreement between Galicia's Government and EnergyLab to develop a project related with the geothermal heatpumps (hereafter, GSHP) technology. That project consisted in replacing the existing thermal equipment generators (diesel boilers and air-water heat pumps) by GSHP systems in representative public buildings: two nursery schools, a university library, a health centre and a residential building. This new systems will reach the demands of existing heating, cooling and domestic hot water (hereafter, DHW). These buildings can serve as examples of energy and economic savings that can offer this technology. We will show detailed analysis of the GSHP facilities monitored, since the starting-up of them. Which includes: COP's, EER's, energy consumption, operating costs, operation hours of the system, economic and emissions comparative, geothermal exchange evolution graphs, environmental conditions evolution graphs (temperature and demands), etc. The results presented show an example of the important benefits of the GSHP technology and the significant savings that can offer its implementation for heating, cooling and DHW production. Note to the reader: The article number has been corrected on web pages on November 22, 2013.

  16. Fiber-laser-based green-pumped picosecond MgO:sPPLT optical parametric oscillator.

    PubMed

    Chaitanya Kumar, S; Ebrahim-Zadeh, M

    2013-12-15

    We report a stable, high-power, picosecond optical parametric oscillator (OPO) at 160 MHz repetition rate synchronously pumped by a frequency-doubled mode-locked Yb-fiber laser at 532 nm and tunable in the near-infrared, across 874-1008 nm (signal) and 1126-1359 nm (idler). Using a 30-mm-long MgO:sPPLT crystal, the OPO provides average output power up to 780 mW in the signal at 918.58 nm and 600 mW in the idler at 1242 nm. The device operates stably over many days, even close to degeneracy, exhibiting passive long-term power stability better than 1.8% rms in the signal and 2.4% rms in the idler over 2.5 h at a temperature of 55°C. We investigate spectral and temporal characteristics of the signal pulses under different conditions and demonstrate cavity-length tuning enabled by the dispersion properties of MgO:sPPLT. The output signal pulses have a duration of 2.4 ps at 967 nm.

  17. Towards an optofluidic pump?

    NASA Astrophysics Data System (ADS)

    Emile, Olivier; Emile, Janine

    2016-12-01

    Most of the vibrating mechanisms of optofluidic systems are based on local heating of membranes that induces liquid flow.We report here a new type of diaphragm pump in a liquid film based on the optical radiation pressure force. We modulate a low power laser that generates, at resonance, a symmetric vibration of a free standing soap film. The film lifetime strongly varies from 56 s at low power (2 mW) to 2 s at higher power (70 mW). Since the laser beam only acts mechanically on the interfaces, such a pump could be easily implemented on delicate microequipment on chips or in biological systems.

  18. A combined method for triplex pump fault diagnosis based on wavelet transform, fuzzy logic and neuro-networks

    NASA Astrophysics Data System (ADS)

    Kong, Fansen; Chen, Ruheng

    2004-01-01

    A new combined method based on wavelet transformation, fuzzy logic and neuro-networks is proposed for fault diagnosis of a triplex. The failure characteristics of the fluid- and dynamic-end can be divided into wavelet transform in different scales at the same time (in: Jun Zhu et al. (Eds.), Proceedings of an International Conference on Condition Monitoring. National Defense Industry Press, Beijing, 1997, pp. 271-275). Therefore, the characteristic variables can be constructed making use of the coefficients of Edgeworth asymptotic spectrum expansion formula and fuzzified to train the neuro-network to identify the faults of fluid- and dynamic-end of triplex pump in fuzzy domain. Tests indicate that the information of wavelet transformation in scale 2 is related to the meshing state of the gear and the information in scales 4 and 5 is related to the running state of fluid-end. Good agreement between analytical and experimental results has been obtained.

  19. Today's ground source heat pumps

    SciTech Connect

    Bose, J.E.

    1993-01-01

    Ground source heat pumps are one of the nation's fastest growing businesses in terms of increased sales of equipment as reported by water source heat pump manufacturers. The success can be attributed in part to these heat pump's reputation as a cost saving system and more recently as an environmentally sound concept. Engineers having an interest in ground source technology come from a large and diverse audience consisting of those who have heard about ground source systems and are contemplating entering the business and those who are experienced and looking to broaden their application base. This article discusses the water source heat pump and its benefits, the commercial Water Loop Heat Pump (WLHP), the ground source heat pump, the commercial Closed Loop/Ground Coupled WLHP, designing a ground heat exchanger, information available for design, and successful systems.

  20. Long life coolant pump technology

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Design concepts were investigated to improve space system coolant pump technology to be suitable for mission durations of two years and greater. These design concepts included an improved bearing system for the pump rotating elements, consisting of pressurized conical bearings. This design was satisfactorily endurance tested as was a new prototype pump built using various other improved design concepts. Based upon an overall assessment of the results of the program it is concluded that reliable coolant pumps can be designed for three year space missions.

  1. 123. UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ...

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

    123. UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751). PUMP ON LEFT; HYDRAULIC CONTROL PANEL FOR UMBILICAL MAST AND TRENCH DOORS IN CENTER OF ROOM, FACING WEST. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  2. 18. Electrically driven pumps in Armory Street Pump House. Pumps ...

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

    18. Electrically driven pumps in Armory Street Pump House. Pumps in background formerly drew water from the clear well. They went out of service when use of the beds was discontinued. Pumps in the foreground provide high pressure water to Hamden. - Lake Whitney Water Filtration Plant, Armory Street Pumphouse, North side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  3. Ultra-broadband Superradiant Pulses from Femtosecond Laser Pumped InP based Quantum Well Laser Diode

    NASA Astrophysics Data System (ADS)

    Liu, Jingjing

    Laser techniques, such as gain / Q switching, mode-locking, have successfully overcome the energy restriction of gain clamping in the stead-state operated lasers, and allowed the generation of giant pulses with short pulse durations. However, gain saturation further limits the amount of stored energy in a gain medium, and therefore limits the possible maximum pulse energy obtained by laser techniques. Here we circumvent both gain clamping and the capacity limitation of energy storage by operating the double-quantum-well laser diode chips on ultrafast gain-switching model using femtosecond (fs) laser pulses as the optical pump. The advantage of our pumping approach is that the fs pulse can instantly produce a very large number of carriers, and therefore enable the formation of non-equilibrium coherent e-h BCS-like condensate state in a large energy region from the lowest QW subband edges to the highest subband and then obtain the ultra-broadband superradiant pulses. Superradiance (SR) or the coherent spontaneous emission is not a new quantum optics phenomenon, which has been proposed in 1954 by R. Dicke, even earlier than the invention of laser. It is famous as by its ultrashort duration, high peak power, high coherence and high timing jitter. Recently, femtosecond SR pulses have been generated from semiconductors. This investigation has revived both theoretical and experimental studies of SR emission. In this thesis, we have demonstrated the generation of intense, delayed SR pulses from the InP based double quantum well laser diode at room temperature. The 1040 nm femtosecond laser was applied as the optical pumping source, and when the pump power is high enough, the cooperative recombination of e-h pairs from higher order quantum energy levels can occur to generate SR bursts earlier than the cooperative emission from the lower quantum energy levels. Then, ultra-broadband TM polarized SR pulses have been firstly generated at room temperature. Our experiments also

  4. A low sample volume particle separation device with electrokinetic pumping based on circular travelling-wave electroosmosis.

    PubMed

    Lin, Shiang-Chi; Lu, Jau-Ching; Sung, Yu-Lung; Lin, Chih-Ting; Tung, Yi-Chung

    2013-08-07

    Particle separation is a crucial step in sample preparation processes. The preparation of low volume samples is especially important for clinical diagnosis and chemical analysis. The advantages of microfluidic techniques have lead them to become potential candidates for particle separation. However, existing microfluidic devices require external pumping sources and extensive geometric patterns to attain high separation efficiency, which is disadvantageous when handling low volume samples. This paper presents a low sample volume particle separation microfluidic device with low voltage electrokinetic pumping based on circular travelling-wave electroosmosis (TWEO). Computational numerical software was utilized to simulate two electrokinetic mechanisms: circular TWEO and dielectrophoresis (DEP). The circular TWEO shear flow generates a velocity gradient in the radial direction which causes a shear stress-induced force to drag particles into the center region of the device. In contrast, the non-parallel electrodes induce negative DEP forces which push polystyrene beads towards the peripheral regions; the magnitude of the DEP forces are dependent on the sizes of the polystyrene beads. We used particles of various sizes to experimentally prove the concept of particle separation. Our experiments show that 15 μm beads are dragged into the center region due to the shear stress-induced force, and 1 μm beads move towards the outer region because of the large negative DEP force. The results show a separation purity of 94.4% and 80.0% for 15 μm and 1 μm beads respectively. We further demonstrated particle isolation from a sample of containing a small proportion of 6 μm beads mixed with 1 μm beads at a concentration ratio of 1 : 300. Therefore, the innovative device developed in this paper provides a promising solution to allow particle separation in sample volumes as low as 50 nL.

  5. Direct comparison of shot-to-shot noise performance of all normal dispersion and anomalous dispersion supercontinuum pumped with sub-picosecond pulse fiber-based laser.

    PubMed

    Klimczak, Mariusz; Soboń, Grzegorz; Kasztelanic, Rafał; Abramski, Krzysztof M; Buczyński, Ryszard

    2016-01-13

    Coherence of supercontinuum sources is critical for applications involving characterization of ultrafast or rarely occurring phenomena. With the demonstrated spectral coverage of supercontinuum extending from near-infrared to over 10 μm in a single nonlinear fiber, there has been a clear push for the bandwidth rather than for attempting to optimize the dynamic properties of the generated spectrum. In this work we provide an experimental assessment of the shot-to-shot noise performance of supercontinuum generation in two types of soft glass photonic crystal fibers. Phase coherence and intensity fluctuations are compared for the cases of an anomalous dispersion-pumped fiber and an all-normal dispersion fiber. With the use of the dispersive Fourier transformation method, we demonstrate that a factor of 100 improvement in signal-to-noise ratio is achieved in the normal-dispersion over anomalous dispersion-pumped fiber for 390 fs long pump pulses. A double-clad design of the photonic lattice of the fiber is further postulated to enable a pump-related seeding mechanism of normal-dispersion supercontinuum broadening under sub-picosecond pumping, which is otherwise known for similar noise characteristics as modulation instability driven, soliton-based spectra.

  6. A fiber laser pumped dual-wavelength mid-infrared laser based on optical parametric oscillation and intracavity difference frequency generation

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Shang, Yaping; Li, Xiao; Shen, Meili; Xu, Xiaojun

    2017-02-01

    We report a dual-wavelength mid-infrared laser based on intracavity difference frequency generation (DFG) in an MgO-doped periodically poled LiNbO3, which was pumped by a dual-wavelength fiber MOPA consisting of two parts: a dual-wavelength seed and a power amplifier. The maximum pump power was 74.1 W and the wavelengths were 1060 nm and 1090 nm. The wavelengths of the mid-infrared output were 3.1 µm and 3.4 µm under maximum pump power with a total idler power of 6.57 W. The corresponding pump-to-idler slope efficiency reached 12%. The contrast for the peak intensity of the emissions for the two idlers was 0.6. A power preamplifier was added in a further experiment to enhance the contrast. The idler output reached 4.45 W under the maximum pump power of 70 W, which was lower than before. However, the contrast for the idler emission peak intensity was increased to 1.18. The signal wave generated in the experiment only had a single wavelength around 1.6 µm, indicating that two kinds of nonlinear processes occurred in the experiment, namely optical parametric oscillation and intracavity DFG.

  7. Direct comparison of shot-to-shot noise performance of all normal dispersion and anomalous dispersion supercontinuum pumped with sub-picosecond pulse fiber-based laser

    PubMed Central

    Klimczak, Mariusz; Soboń, Grzegorz; Kasztelanic, Rafał; Abramski, Krzysztof M.; Buczyński, Ryszard

    2016-01-01

    Coherence of supercontinuum sources is critical for applications involving characterization of ultrafast or rarely occurring phenomena. With the demonstrated spectral coverage of supercontinuum extending from near-infrared to over 10 μm in a single nonlinear fiber, there has been a clear push for the bandwidth rather than for attempting to optimize the dynamic properties of the generated spectrum. In this work we provide an experimental assessment of the shot-to-shot noise performance of supercontinuum generation in two types of soft glass photonic crystal fibers. Phase coherence and intensity fluctuations are compared for the cases of an anomalous dispersion-pumped fiber and an all-normal dispersion fiber. With the use of the dispersive Fourier transformation method, we demonstrate that a factor of 100 improvement in signal-to-noise ratio is achieved in the normal-dispersion over anomalous dispersion-pumped fiber for 390 fs long pump pulses. A double-clad design of the photonic lattice of the fiber is further postulated to enable a pump-related seeding mechanism of normal-dispersion supercontinuum broadening under sub-picosecond pumping, which is otherwise known for similar noise characteristics as modulation instability driven, soliton-based spectra. PMID:26759188

  8. Selection of Cluster Well Pumping Unit Wire Rope Based on Fuzzy Multi-Objective Decision-Making

    NASA Astrophysics Data System (ADS)

    Qu, Wentao; Wang, Yajuan; Kang, Xianzhi; Xi, Xiaopeng; Zou, Wei

    Influencing factors in cluster well pumping unit wire rope was analyzed corresponding index system. According to its characteristics, combined with fuzzy set theory, a multi-objective decision-making model of luster well pumping unit wire rope was set up, and the example of application was given to verify its feasibility.

  9. Quasilinear theory of terahertz free-electron lasers based on Compton scattering of incoherent pump wave by intense relativistic electron beam

    NASA Astrophysics Data System (ADS)

    Ginzburg, N. S.; Kocharovskaya, E. R.

    2016-08-01

    The use of incoherent broadband pump radiation for improving the electron efficiency in the free-electron lasers (FEL) based on stimulated backscattering is considered. On the basis of a quasilinear approach, it is shown that the efficiency increases in proportion to the width of the pump spectrum. The effect is owing to a broadening of the spectrum of synchronous combination waves and realization of a mechanism of stochastic particle deceleration. The injection of a monochromatic seed signal in a single pass FEL amplifier or the implementation of a selective high-Q resonator in an FEL oscillator makes the high-frequency scattered radiation be monochromatic in spite of an incoherent pumping. In the regime of stochastic particle deceleration, the efficiency only slightly depends on the spread of the beam parameters, which is beneficial for a terahertz FEL powered by intense relativistic electron beams.

  10. Intracavity optical parametric oscillator based on GTR-KTP driven by laser-diode end-pumped Q-switched Nd:YVO 4 laser

    NASA Astrophysics Data System (ADS)

    Yang, Jian-Fei; Zhang, Bai-Tao; Huang, Hai-Tao; He, Jing-Liang; Xu, Jin-Long; Zhao, Shuang; Yang, Xiu-Qin; Qiu, Gang; Liu, Zong-Kai

    2010-07-01

    An efficient, eye-safe, high-repetition-rate, single-resonant intracavity optical parameter oscillator, driven by a laser-diode (LD) end-pumped acousto-optically Q-switched Nd:YVO 4 laser, based on high gray-trace resistance KTiPO 4 (GTR-KTP), was demonstrated. With a pump power of 13.8 W and frequency repetition rate of 40 kHz, the maximum power of 1.72 W with pulse width of 2.09 ns at signal wavelength 1572 nm is obtained. The corresponding peak power and single pulse energy is calculated to be 21 kW and 43 μJ, respectively. And the conversion efficiency from incident pump power at 808 nm to output power at signal wavelength 1572 nm is about 12.5%. The output instability is measured only to be 1% within 1 h.

  11. Development of a web-based observational tool for detecting intravenous medication errors with smart infusion pumps.

    PubMed

    Ohashi, Kumiko; Dykes, Patricia; McIntosh, Kathleen; Buckley, Elizabeth; Wien, Matt; Kreitzman, Kevin; Dumais, Michael; Bates, David W

    2013-01-01

    Computerized smart infusion pumps have been widely implemented to decrease the rate of intravenous (IV) medication errors in hospitals. However, these devices have not always achieved their potential, and important IV errors still persist. Findings from a previous study [1] that assessed the frequency of IV medication errors and the impact of smart infusion pumps identified major issues related to use of smart infusion pumps in a single facility, but generalizability of these results is uncertain. Additionally, lack of standardized methodology for measuring these errors remains an issue. In this study, we developed an observational tool to capture IV medication errors through iterative participatory design with interdisciplinary experts and then tested the tool by using incident cases regarding smart pump errors. We found that the tool could capture all smart infusion pump errors and is ready for testing for use as standard data collection tool in different hospital settings.

  12. Bioinspired artificial single ion pump.

    PubMed

    Zhang, Huacheng; Hou, Xu; Zeng, Lu; Yang, Fu; Li, Lin; Yan, Dadong; Tian, Ye; Jiang, Lei

    2013-10-30

    Bioinspired artificial functional nanochannels for intelligent molecular and ionic transport control at the nanoscale have wide potential applications in nanofluidics, energy conversion, and biosensors. Although various smart passive ion transport properties of ion channels have been artificially realized, it is still hugely challenging to achieve high level intelligent ion transport features in biological ion pumps. Here we show a unique bioinspired single ion pump based on a cooperative pH response double-gate nanochannel, whose gates could be opened and closed alternately/simultaneously under symmetric/asymmetric pH environments. With the stimulation of the double-gate nanochannel by continuous switching of the symmetric/asymmetric pH stimuli, the bioinspired system systematically realized three key ionic transport features of biological ion pumps, including an alternating gates ion pumping process under symmetric pH stimuli, transformation of the ion pump into an ion channel under asymmetric pH stimuli, and a fail-safe ion pumping feature under both symmetric and asymmetric pH stimuli. The ion pumping processes could well be reproduced under a concentration gradient. With the advantages of the extraordinary ionic transport functions of biological ion pumps, the bioinspired ion pump should find widespread applicability in active transportation-controlling smart nanofluidic devices, efficient energy conversions, and seawater desalinization, and open the way to design and develop novel bioinspired intelligent artificial nanochannel materials.

  13. Reactor coolant pump flywheel

    DOEpatents

    Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

    2013-11-26

    A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

  14. Gallic acid-based indanone derivative interacts synergistically with tetracycline by inhibiting efflux pump in multidrug resistant E. coli.

    PubMed

    Dwivedi, Gaurav Raj; Tiwari, Nimisha; Singh, Aastha; Kumar, Akhil; Roy, Sudeep; Negi, Arvind Singh; Pal, Anirban; Chanda, Debabrata; Sharma, Ashok; Darokar, Mahendra P

    2016-03-01

    The purpose of the present study was to study the synergy potential of gallic acid-based derivatives in combination with conventional antibiotics using multidrug resistant cultures of Escherichia coli. Gallic acid-based derivatives significantly reduced the MIC of tetracycline against multidrug resistant clinical isolate of E. coli. The best representative, 3-(3',4,'5'-trimethoxyphenyl)-4,5,6-trimethoxyindanone-1, an indanone derivative of gallic acid, was observed to inhibit ethidium bromide efflux and ATPase which was also supported by in silico docking. This derivative extended the post-antibiotic effect and decreased the mutation prevention concentration of tetracycline. This derivative in combination with TET was able to reduce the concentration of TNFα up to 18-fold in Swiss albino mice. This derivative was nontoxic and well tolerated up to 300 mg/kg dose in subacute oral toxicity study in mice. This is the first report of gallic acid-based indanone derivative as drug resistance reversal agent acting through ATP-dependent efflux pump inhibition.

  15. Cavity-induced microstreaming for simultaneous on-chip pumping and size-based separation of cells and particles.

    PubMed

    Patel, Maulik V; Nanayakkara, Imaly A; Simon, Melinda G; Lee, Abraham P

    2014-10-07

    We present a microfluidic platform for simultaneous on-chip pumping and size-based separation of cells and particles without external fluidic control systems required for most existing platforms. The device utilizes an array of acoustically actuated air/liquid interfaces generated using dead-end side channels termed Lateral Cavity Acoustic Transducers (LCATs). The oscillating interfaces generate local streaming flow while the angle of the LCATs relative to the main channel generates a global bulk flow from the inlet to the outlet. The interaction of these two competing velocity fields (i.e. global bulk velocity vs. local streaming velocity) is responsible for the observed separation. It is shown that the separation of 5 μm and 10 μm polystyrene beads is dependent on the ratio of these two competing velocity fields. The experimental and simulation results suggest that particle trajectories based only on Stokes drag force cannot fully explain the separation behavior and that the impact of additional forces due to the oscillating flow field must be considered to determine the trajectory of the beads and ultimately the separation behavior of the device. To demonstrate an application of this separation platform with cellular components, smaller red blood cells (7.5 ± 0.8 μm) are separated from larger K562 cells (16.3 ± 2.0 μm) with viabilities comparable to those of controls based on a trypan blue exclusion assay.

  16. Hydraulic optimization of "S" characteristics of the pump-turbine for Xianju pumped storage plant

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

    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.

  17. Solar Pump

    NASA Technical Reports Server (NTRS)

    Pique, Charles

    1987-01-01

    Proposed pump moves liquid by action of bubbles formed by heat of sun. Tube of liquid having boiling point of 100 to 200 degrees F placed at focal axis of cylindrical reflector. Concentrated sunlight boils liquid at focus, and bubbles of vapor rise in tube, carrying liquid along with them. Pressure difference in hot tube sufficient to produce flow in large loop. Used with conventional flat solar heating panel in completely solar-powered heat-storage system.

  18. Heat pump

    SciTech Connect

    Apte, A.J.

    1982-11-30

    A single working fluid heat pump system having a turbocompressor with a first fluid input for the turbine and a second fluid input for the compressor, and a single output volute or mixing chamber for combining the working fluid output flows of the turbine and the compressor. The system provides for higher efficiency than single fluid systems whose turbine and compressor are provided with separate output volutes.

  19. Research on wear properties of centrifugal dredge pump based on liquid-solid two-phase fluid simulations

    NASA Astrophysics Data System (ADS)

    Peng, G. J.; Luo, Y. Y.; Wang, Z. W.

    2015-01-01

    The impeller and casing of dredge pump are worn by sediment in the flow. However, there are few studies about abrasion of the impeller and casing for normal pump operating conditions. This paper investigated the relationship between the wear rates on the surfaces of the impeller as well as casing and the sediment concentration, with the distribution of the wear rates for normal pump operating condition analyzed. An Eulerian-Lagrangian Computational Fluid Dynamics (CFD) procedure was used to simulate steady liquid-solid two-phase flow for various operating conditions. The Finnie model was then used to predict the abrasion. The results show that, the wear rate relative value of impeller and casing surface increase as the sediment concentration increases. The wear rate relative value of impeller and casing surface is larger when the pump is in low flow rate condition, and the value of casing surface is larger than that of the impeller. The wear rate relative value of pump is low when pump is in high efficiency condition. This paper shows the abrasion characteristics on the impeller and casing with sediment flow and provides reference data for predicting the abrasion conditions in the flow passage components for a dredge pump.

  20. Size-based cell sorting with a resistive pulse sensor and an electromagnetic pump in a microfluidic chip.

    PubMed

    Song, Yongxin; Li, Mengqi; Pan, Xinxiang; Wang, Qi; Li, Dongqing

    2015-02-01

    An electrokinetic microfluidic chip is developed to detect and sort target cells by size from human blood samples. Target-cell detection is achieved by a differential resistive pulse sensor (RPS) based on the size difference between the target cell and other cells. Once a target cell is detected, the detected RPS signal will automatically actuate an electromagnetic pump built in a microchannel to push the target cell into a collecting channel. This method was applied to automatically detect and sort A549 cells and T-lymphocytes from a peripheral fingertip blood sample. The viability of A549 cells sorted in the collecting well was verified by Hoechst33342 and propidium iodide staining. The results show that as many as 100 target cells per minute can be sorted out from the sample solution and thus is particularly suitable for sorting very rare target cells, such as circulating tumor cells. The actuation of the electromagnetic valve has no influence on RPS cell detection and the consequent cell-sorting process. The viability of the collected A549 cell is not impacted by the applied electric field when the cell passes the RPS detection area. The device described in this article is simple, automatic, and label-free and has wide applications in size-based rare target cell sorting for medical diagnostics.

  1. Recursive approach of EEG-segment-based principal component analysis substantially reduces cryogenic pump artifacts in simultaneous EEG-fMRI data.

    PubMed

    Kim, Hyun-Chul; Yoo, Seung-Schik; Lee, Jong-Hwan

    2015-01-01

    Electroencephalography (EEG) data simultaneously acquired with functional magnetic resonance imaging (fMRI) data are preprocessed to remove gradient artifacts (GAs) and ballistocardiographic artifacts (BCAs). Nonetheless, these data, especially in the gamma frequency range, can be contaminated by residual artifacts produced by mechanical vibrations in the MRI system, in particular the cryogenic pump that compresses and transports the helium that chills the magnet (the helium-pump). However, few options are available for the removal of helium-pump artifacts. In this study, we propose a recursive approach of EEG-segment-based principal component analysis (rsPCA) that enables the removal of these helium-pump artifacts. Using the rsPCA method, feature vectors representing helium-pump artifacts were successfully extracted as eigenvectors, and the reconstructed signals of the feature vectors were subsequently removed. A test using simultaneous EEG-fMRI data acquired from left-hand (LH) and right-hand (RH) clenching tasks performed by volunteers found that the proposed rsPCA method substantially reduced helium-pump artifacts in the EEG data and significantly enhanced task-related gamma band activity levels (p=0.0038 and 0.0363 for LH and RH tasks, respectively) in EEG data that have had GAs and BCAs removed. The spatial patterns of the fMRI data were estimated using a hemodynamic response function (HRF) modeled from the estimated gamma band activity in a general linear model (GLM) framework. Active voxel clusters were identified in the post-/pre-central gyri of motor area, only from the rsPCA method (uncorrected p<0.001 for both LH/RH tasks). In addition, the superior temporal pole areas were consistently observed (uncorrected p<0.001 for the LH task and uncorrected p<0.05 for the RH task) in the spatial patterns of the HRF model for gamma band activity when the task paradigm and movement were also included in the GLM.

  2. Tunable picosecond THz-wave generation based on trapezoidal MgO:LiNbO3 crystal in novel pentagram-shaped pump-enhancement cavity

    NASA Astrophysics Data System (ADS)

    Takida, Yuma; Tadokoro, Yuzuru; Kumagai, Hiroshi; Nashima, Shigeki; Kobayashi, Ataru

    2013-03-01

    It is well known that lithium niobate (LiNbO3) has excellent characteristics for efficient tunable/broadband THz-wave generation. Over the last few years, we have investigated novel THz-wave sources based on MgO-doped LiNbO3 (MgO:LiNbO3), and have succeeded in developing a tunable picosecond THz-wave source by using a novel pentagramshaped pump-enhancement cavity. One of the limiting factors in efficient THz-wave generation is the strong absorption by MgO:LiNbO3 in THz-wave region. To overcome this problem, we employ a surface-emitted configuration which consists of a trapezoidal MgO:LiNbO3 crystal and a pump-enhancement cavity folded in the shape of a pentagram. The pentagram-shaped cavity is designed for the noncollinear dual resonance of both pump and one of the down-converted waves. As a result, 1.5-ps pump pulses from a mode-locked Ti:sapphire laser operating at 780 nm allow tunable THzwave generation via parametric down-conversion resulting from stimulated phonon-polariton scattering in the MgO:LiNbO3 crystal. By slightly translating the position of one of the cavity mirrors, we experimentally find that the THz-wave frequency is tunable in the range from 0.1 to 3.5 THz with the average output power of dozens of nanowatts. The maximum THz-wave average power is up to 40 nW around 2 THz at the pump power of 800 mW, which is several times higher than the THz-wave output generated by using rectangular MgO:LiNbO3 crystals for Si-prism-coupled configuration under the same pump condition.

  3. Energy saving pump and pumping system

    SciTech Connect

    Chang, K.C.

    1983-08-02

    A centrifugal pump and a pumping system are disclosed that recover hydraulic energy in response to flow capacity reduction and spontaneously provide a recirculating flow at low capacities when pump cooling is needed. From a upstream source the fluid is guided by two suction lines to two parallel pumping mechanisms housed by a common discharge casing. Said pumping mechanisms have a combined hydraulic characteristic that the first pumping mechanism will force a reverse flow through the second pumping mechanism, when pump discharge is reduced by the system below a certain low flow rate. The reverse flow will then return to the upstream fluid source through a suction line. The pump is the protected from overheating by a circulating flow at low flow capacities. At the same time, said reverse flow generates a turbine action on the second pumping mechanism and transmits the contained hydraulic energy back to the rotor and thereby results in power saving at low flow capacities.

  4. Pump turbines. January 1974-February 1990 (A Bibliography from Fluidex data base). Report for January 1974-February 1990

    SciTech Connect

    Not Available

    1990-04-01

    This bibliography contains citations concerning pump turbines, mostly pertaining to pumped storage, but including a few references to other applications. The abstracts cover design, development, testing, operational evaluation, and problem areas. Many of the abstracts reference reports on flow characteristics, including draft tube surges, dynamic loads and forces, vibration, cavitation, and starting problems. Citations cover both the pumping mode and the turbine (generating) mode, for analyses of speed rise, overpressure, overspeed, and general flow investigations. (This updated bibliography contains 348 citations, 112 of which are new entries to the previous edition.)

  5. DISK PUMP FEASIBILITY INVESTIGATION,

    DTIC Science & Technology

    The disk pump was investigated at the Air Force Rocket Propulsion Laboratory (AFRPL) to determine the feasibility of using a novel viscous pumping... pump primarily for application as an inducer. The disk pump differs drastically from conventional pumps because of the following major factors: (1) The...The pump inlet relative velocity is equal only to the through flow velocity between the disks. Therefore, there is good indication that the disk pump will

  6. Results of Protocol-based Perioperative Management in Off-Pump Coronary Artery Bypass Grafting for Patients with Non-dialysis-dependent Chronic Kidney Disease

    PubMed Central

    Kim, Jeong-Won; Sim, Hyung Tae; Yoo, Jae Suk; Kim, Dong Jin; Cho, Kwang Ree

    2016-01-01

    Background Recent studies have demonstrated the benefits of off-pump coronary bypass grafting over the on-pump technique in patients with chronic kidney disease (CKD). To further reduce the risk of acute kidney injury and the need for renal replacement therapy, even in patients undergoing off-pump coronary artery bypass grafting, we adopted protocol-based perioperative management for patients with CKD. Methods From December 2012 to March 2015, 265 patients underwent isolated off-pump coronary artery bypass grafting. To analyze renal function in a stable condition, we excluded 12 dialysis-dependent end stage renal failure and 10 emergency or urgent cases. Among the remaining 243 patients, 208 patients had normal kidney function (normal group), and 35 patients had CKD (CKD group). Minimizing contrast exposure, ensuring adequate hydration, using strict drug dosage adjustment, and optimizing hemodynamic status were key elements of the protocol for the CKD group. Results The risk of acute kidney injury was about ×3 higher in the CKD group than in the normal group (p=0.01). Estimated glomerular filtration rates and serum creatinine levels deteriorated until the third postoperative day in the CKD group. However, by adopting protocol-based perioperative management, this transient renal dysfunction recovered to preoperative levels by the fifth postoperative day without requiring renal replacement therapy in all cases. Conclusion Off-pump coronary bypass surgery combined with this protocol-based perioperative management strategy in patients with non-dialysis-dependent CKD could mostly be performed without renal replacement therapy. PMID:27965919

  7. CHARACTERIZATION OF AEROSOLS FROM A WATER-BASED CLEANER APPLIED WITH A HAND-PUMP SPRAYER

    EPA Science Inventory

    The paper gives results of tests that were performed in a controlled-environment test room to measure particle concentrations and size distributions and concentrations of selected volatily organic compounds during, and following, application of water-based cleaners to realistic s...

  8. Well pump

    SciTech Connect

    Page, J.S.

    1983-03-08

    Well fluid pumping apparatus comprises: (A) body structure defining an upright plunger bore, (B) a plunger reciprocable in that bore, (C) the body structure also defining a chamber sidewardly offset from an axis defined by the plunger bore and communicating with the bore, and (D) valving carried by the body structure to pass intake fluid via the chamber into the plunger bore in response to stroking of the plunger in one direction in the bore, and to pass discharge fluid from the plunger bore into and from the chamber in response to stroking of the plunger in the opposite direction in the bore.

  9. Human Aorta Is a Passive Pump

    NASA Astrophysics Data System (ADS)

    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.

  10. An Integrated Microfabricated Chip with Double Functions as an Ion Source and Air Pump Based on LIGA Technology

    PubMed Central

    Li, Hua; Jiang, Linxiu; Guo, Chaoqun; Zhu, Jianmin; Jiang, Yongrong; Chen, Zhencheng

    2017-01-01

    The injection and ionization of volatile organic compounds (VOA) by an integrated chip is experimentally analyzed in this paper. The integrated chip consists of a needle-to-cylinder electrode mounting on the Polymethyl Methacrylate (PMMA) substrate. The needle-to-cylinder electrode is designed and fabricated by Lithographie, Galvanoformung and Abformung (LIGA) technology. In this paper, the needle is connected to a negative power supply of −5 kV and used as the cathode; the cylinder electrodes are composed of two arrays of cylinders and serve as the anode. The ionic wind is produced based on corona and glow discharges of needle-to-cylinder electrodes. The experimental setup is designed to observe the properties of the needle-to-cylinder discharge and prove its functions as an ion source and air pump. In summary, the main results are as follows: (1) the ionic wind velocity produced by the chip is about 0.79 m/s at an applied voltage of −3300 V; (2) acetic acid and ammonia water can be injected through the chip, which is proved by pH test paper; and (3) the current measured by a Faraday cup is about 10 pA for acetic acid and ammonia with an applied voltage of −3185 V. The integrated chip is promising for portable analytical instruments, such as ion mobility spectrometry (IMS), field asymmetric ion mobility spectrometry (FAIMS), and mass spectrometry (MS). PMID:28054980

  11. Spin exchange optical pumping based polarized {sup 3}He filling station for the Hybrid Spectrometer at the Spallation Neutron Source

    SciTech Connect

    Jiang, C. Y.; Tong, X.; Brown, D. R.; Culbertson, H.; Kadron, B.; Robertson, J. L.; Graves-Brook, M. K.; Hagen, M. E.; Lee, W. T.; Winn, B.

    2013-06-15

    The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60 Degree-Sign horizontal and 15 Degree-Sign vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized {sup 3}He filling station based on the spin exchange optical pumping method. It is designed to supply polarized {sup 3}He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the {sup 3}He pressure with respect to the scattered neutron energies. The depolarized {sup 3}He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

  12. Tuning of whispering gallery modes in a magnetic-fluid-infiltrated silica capillary based on lateral pumping scheme

    NASA Astrophysics Data System (ADS)

    Li, Yuetao; Zhang, Hao; Liu, Bo; Wu, Jixuan; Song, Binbin; Yan, Donglin; Yang, Chengkun

    2017-01-01

    An all-optical tuning method of whispering gallery modes (WGMs) in a silica capillary based on lateral pumping scheme has been proposed and experimentally demonstrated by exploiting the photo-thermal effect of magnetic fluids (MFs) infiltrated into a micro-capillary. The WGMs are coupled from a tapered fiber perpendicular to the silica capillary. Experimental results indicate that the microresonator integrated with MFs shows a Q-factor of 1.2867 × 104 and its optical tunability reaches 0.0382 nm/(mW · mm-2) under 532 nm laser illumination. Compared with the one infiltrated with pure water, our proposed capillary shows an optical tuning sensitivity increase of about 4270 times. The experimental results on the WGM resonance wavelength sensitivity for the capillaries with different diameters are in accordance with our simulation outcome using radially dependent heat conducting equation. Further experimental studies indicate that the proposed microresonator possesses a good spectral reversibility. Moreover, the dynamic response experiment shows that the rise and fall time of this microresonator is about 231 ms and 255 ms, respectively. The above intriguing features make the proposed WGM resonator a promising candidate for potential applications in optical filtering, microfluidic sensing, and signal processing as well as reconfigurable devices for future all-optical networks.

  13. An Integrated Microfabricated Chip with Double Functions as an Ion Source and Air Pump Based on LIGA Technology.

    PubMed

    Li, Hua; Jiang, Linxiu; Guo, Chaoqun; Zhu, Jianmin; Jiang, Yongrong; Chen, Zhencheng

    2017-01-04

    The injection and ionization of volatile organic compounds (VOA) by an integrated chip is experimentally analyzed in this paper. The integrated chip consists of a needle-to-cylinder electrode mounting on the Polymethyl Methacrylate (PMMA) substrate. The needle-to-cylinder electrode is designed and fabricated by Lithographie, Galvanoformung and Abformung (LIGA) technology. In this paper, the needle is connected to a negative power supply of -5 kV and used as the cathode; the cylinder electrodes are composed of two arrays of cylinders and serve as the anode. The ionic wind is produced based on corona and glow discharges of needle-to-cylinder electrodes. The experimental setup is designed to observe the properties of the needle-to-cylinder discharge and prove its functions as an ion source and air pump. In summary, the main results are as follows: (1) the ionic wind velocity produced by the chip is about 0.79 m/s at an applied voltage of -3300 V; (2) acetic acid and ammonia water can be injected through the chip, which is proved by pH test paper; and (3) the current measured by a Faraday cup is about 10 pA for acetic acid and ammonia with an applied voltage of -3185 V. The integrated chip is promising for portable analytical instruments, such as ion mobility spectrometry (IMS), field asymmetric ion mobility spectrometry (FAIMS), and mass spectrometry (MS).

  14. Pump apparatus

    SciTech Connect

    Kime, J.A.

    1987-02-17

    This patent describes a gas-oil well production system for pumping formation fluid wherein a down hole pump is provided having a barrel including a barrel fluid inlet, a barrel fluid outlet, a barrel chamber, and a plunger mounted in the barrel chamber having a plunger chamber. The plunger is reciprocally driven between an upper terminal position at the end of the plunger upstroke and a lower terminal position at the end of the plunger downstroke. The method for removing developed gaseous fluids in the formation fluid from the barrel chamber comprises: drawing formation fluid into the barrel chamber during the plunger upstroke; providing gas port means in the barrel; expelling the developed gaseous fluids from the barrel chamber through the gas port means during the occurrence of that portion of the plunger downstroke from the upper terminal position of the gas port means; and substantially blocking the gas port means and moving formation fluid into the plunger chamber during the occurrence of that portion of the plunger downstroke from below the gas port means to the lower terminal position.

  15. Ultrasound based mitral valve annulus tracking for off-pump beating heart mitral valve repair

    NASA Astrophysics Data System (ADS)

    Li, Feng P.; Rajchl, Martin; Moore, John; Peters, Terry M.

    2014-03-01

    Mitral regurgitation (MR) occurs when the mitral valve cannot close properly during systole. The NeoChordtool aims to repair MR by implanting artificial chordae tendineae on flail leaflets inside the beating heart, without a cardiopulmonary bypass. Image guidance is crucial for such a procedure due to the lack of direct vision of the targets or instruments. While this procedure is currently guided solely by transesophageal echocardiography (TEE), our previous work has demonstrated that guidance safety and efficiency can be significantly improved by employing augmented virtuality to provide virtual presentation of mitral valve annulus (MVA) and tools integrated with real time ultrasound image data. However, real-time mitral annulus tracking remains a challenge. In this paper, we describe an image-based approach to rapidly track MVA points on 2D/biplane TEE images. This approach is composed of two components: an image-based phasing component identifying images at optimal cardiac phases for tracking, and a registration component updating the coordinates of MVA points. Preliminary validation has been performed on porcine data with an average difference between manually and automatically identified MVA points of 2.5mm. Using a parallelized implementation, this approach is able to track the mitral valve at up to 10 images per second.

  16. Geothermal pumping systems

    SciTech Connect

    Hanold, R.J.

    1984-10-18

    After successful field testing of a prototype pressurized lubrication system designed to prevent brine intrusion and loss of lubricating oil from the motor and protector sections of electric submersible pumps, a second-generation lubrication system has been designed, fabricated, and laboratory tested. Based on a sensitive downhole pressure regulator, this system is not depth limited and it accurately controls the differential pressure between the motor oil and the external brine. The first production lengths of metal sheathed power cable have been fabricated by Halpen Engineering and delivered to REDA for testing and evaluation. Laboratory tests performed on prototype metal sheathed cable samples have demonstrated the durability of this power cable design. The East Mesa Pump Test Facility is currently being activated for high-horsepower pumping system tests that are scheduled to commence during the first quarter of FY 85. A 300-horsepower REDA pumping system equipped with a pressure regulator controlled lubrication system and a metal sheathed power cable is being fabricated for testing in this unique facility.

  17. The first field-based descriptions of pumping-induced saltwater intrusion and upconing

    NASA Astrophysics Data System (ADS)

    Houben, Georg; Post, Vincent E. A.

    2016-09-01

    Development of the ideas about the equilibrium between freshwater and saline water has received considerable attention in the literature, but little has been written so far about the earliest scientific works about well salinization. Based on a review of the literature from the second half of the 19th century and the early 20th century, this historical note explores how insights into groundwater abstraction and saltwater intrusion developed, and examples of the earliest field studies are provided. Fundamental research was driven by the need for increasing water supply, but the progress of science did not lead to sustainable management practices everywhere. Research outcomes were shared between scientists of different countries, marking the beginning of coastal hydrogeology as a scientific specialization in the first decade of the 20th century.

  18. Estimation of left ventricular recovery level based on the motor current waveform analysis on circulatory support with centrifugal blood pump.

    PubMed

    Takahashi, K; Uemura, M; Watanabe, N; Ohuchi, K; Nakamura, M; Fukui, Y; Sakamoto, T; Takatani, S

    2001-09-01

    In a mock circulatory loop simulating the left heart bypass using a centrifugal blood pump, analysis of the motor current waveform of the centrifugal pump was performed to derive a useful parameter to evaluate the status of ventricular function. The relationship between the peak, amplitude, and the peak of the fundamental frequency of the power spectral density of the periodic motor current waveform (MCpsdP) that reflected the pulsatile ventricular pressure, and the peak of the left ventricular pressure (LVP) was examined. Although both peak and amplitude of the motor current waveform showed an excellent correlation with the peak LVP, they failed to predict the opening of the aortic valve. The MCpsdP that corresponds to the frequency of the heart rate showed an excellent correlation with the peak LVP throughout the LVP levels, but the slope between them changed with the opening of the aortic valve. Thus, it is possible to follow the change in the LVP and detect even the opening of the aortic valve, and, hence, the recovery of the left ventricle. However, the slope of the linear regression equation varied, depending on the pump speed. This result implies that the MCpsdP can be possibly used to follow the change of ventricular function during circulatory assistance with a centrifugal blood pump as well as to control the pump speed in response to varying ventricular function.

  19. Prediction of "s" Characteristics of a Pump-Turbine with Small Opening Based on V2F Model

    NASA Astrophysics Data System (ADS)

    Liu, Jintao; Liu, Shuhong; Wu, Yulin; Sun, Yuekun; Zuo, Zhigang

    The characteristic of a pump-turbine during the whole starting or stopping period couldn't be calculated accurately by CFD method and most of turbulence models were found inaccurate in the calculation of small opening condition, so a proper turbulence model was needed for the further study of pump-turbine. V2F model which was valid to the solid wall and SST k-ω model were used to calculate the pump-turbine with two openings that one was a small opening and the other was large opening. Results showed that V2F model can be used to simulate characteristics of pump-turbine in the whole opening range and the SST k-ω model can be used only for large openings. Results of V2F model are accuracy and it realizes the real flow in the near wall region. Results of V2F model can obtain small vortexes and some complex flow phenomenon and they are much different from results of SST k-ω model. The V2F model might be used to simulate the starting or stopping period of a pump-turbine.

  20. Experimental study of an electromagnetic flow meter for liquid metals based on torque measurement during pumping process

    NASA Astrophysics Data System (ADS)

    Dubovikova, N.; Kolesnikov, Y.; Karcher, Ch

    2015-11-01

    This paper presents a detailed experimental study on an electromagnetic flow measurement technique to measure the flow rate of liquid metals. The experimental setup consists of a contactless electromagnetic pump with a torque sensor mounted on the pump shaft. The electromagnetic pump is composed of two rotating steel discs having embedded permanent magnets with alternating poles. The rotation of the discs creates a travelling sinusoidal magnetic field and eddy currents within the liquid metal. The metal is contained inside the duct located between the discs of the pump. The interaction of the magnetic field and the induced eddy currents generates an electromagnetic Lorentz force providing the pumping effect. The flow rate is proportional to this force. The torque sensor measures the moment of the discs due to the Lorentz force, which is converted to a flow rate value. We name the method Lorentz torque velocimetry (LTV). The full calibration procedure and experimental investigation of the LTV are described. The method can be used as a non-contact flow rate control technique for liquid metals.

  1. [Research on magnetic coupling centrifugal blood pump control based on a self-tuning fuzzy PI algorithm].

    PubMed

    Yang, Lei; Yang, Ming; Xu, Zihao; Zhuang, Xiaoqi; Wang, Wei; Zhang, Haibo; Han, Lu; Xu, Liang

    2014-10-01

    The purpose of this paper is to report the research and design of control system of magnetic coupling centrifugal blood pump in our laboratory, and to briefly describe the structure of the magnetic coupling centrifugal blood pump and principles of the body circulation model. The performance of blood pump is not only related to materials and structure, but also depends on the control algorithm. We studied the algorithm about motor current double-loop control for brushless DC motor. In order to make the algorithm adjust parameter change in different situations, we used the self-tuning fuzzy PI control algorithm and gave the details about how to design fuzzy rules. We mainly used Matlab Simulink to simulate the motor control system to test the performance of algorithm, and briefly introduced how to implement these algorithms in hardware system. Finally, by building the platform and conducting experiments, we proved that self-tuning fuzzy PI control algorithm could greatly improve both dynamic and static performance of blood pump and make the motor speed and the blood pump flow stable and adjustable.

  2. Multipass pumped Nd-based thin-disk lasers: continuous-wave laser operation at 1.06 and 0.9 microm with intracavity frequency doubling.

    PubMed

    Pavel, Nicolaie; Lünstedt, Kai; Petermann, Klaus; Huber, Günter

    2007-12-01

    The laser performances of the 1.06 microm (4)F(3/2) --> (4)I(11/2) four-level transition and of the 0.9 microm (4)F(3/2) --> I(9/2)4 quasi-three-level transition were investigated using multipass pumped Nd-based media in thin-disk geometry. When pumping at 0.81 microm into the (4)F(5/2) level, continuous-wave laser operation was obtained with powers in excess of 10 W at 1.06 microm, in the multiwatt region at 0.91 microm in Nd:YVO(4) and Nd:GdVO(4), and at 0.95 microm in Nd:YAG. Intracavity frequency-doubled Nd:YVO(4) thin-disk lasers with output powers of 6.4 W at 532 nm and of 1.6 W at 457 nm were realized at this pumping wavelength. The pumping at 0.88 microm, which is directed into the (4)F(3/2) emitting level, was also employed, and Nd:YVO(4) and Nd:GdVO(4) thin-disk lasers with ~9 W output power at 1.06 microm and visible laser radiation at 0.53 microm with output power in excess of 4 W were realized. Frequency-doubled Nd:vanadate thin-disk lasers with deep blue emission at 0.46 microm were obtained under pumping directly into the (4)F(3/2) emitting level.

  3. Analysis of maximum reach in WDM PON architecture based on distributed Raman amplification and pump recycling technique.

    PubMed

    Kim, Chul Han; Lee, Ju Han; Lee, Kwanil

    2007-10-29

    We analyze the performance of bidirectional WDM PON architecture which utilizes distributed Raman amplification and pump recycling technique. The maximum reach at data rates of 622 Mb/s and 1.25 Gb/s in the proposed WDM PON architecture is calculated by taking into account the effects of power budget, chromatic dispersion of transmission fiber, and Raman amplification-induced noises with a given amount of Raman pump power. From the result, the maximum reach for 622 Mb/s and 1.25 Gb/s signal transmission is calculated to be 65 km and 60 km with a Raman pump power of 700 mW, respectively. We also find that the calculated results agree well with the experimental results which were reported previously.

  4. Efflux Pump Blockers in Gram-Negative Bacteria: The New Generation of Hydantoin Based-Modulators to Improve Antibiotic Activity

    PubMed Central

    Otręebska-Machaj, Ewa; Chevalier, Jacqueline; Handzlik, Jadwiga; Szymańska, Ewa; Schabikowski, Jakub; Boyer, Gérard; Bolla, Jean-Michel; Kieć-Kononowicz, Katarzyna; Pagès, Jean-Marie; Alibert, Sandrine

    2016-01-01

    Multidrug resistant (MDR) bacteria are an increasing health problem with the shortage of new active antibiotic agents. Among effective mechanisms that contribute to the spread of MDR Gram-negative bacteria are drug efflux pumps that expel clinically important antibiotic classes out of the cell. Drug pumps are attractive targets to restore the susceptibility toward the expelled antibiotics by impairing their efflux activity. Arylhydantoin derivatives were investigated for their potentiation of activities of selected antibiotics described as efflux substrates in Enterobacter aerogenes expressing or not AcrAB pump. Several compounds increased the bacterial susceptibility toward nalidixic acid, chloramphenicol and sparfloxacin and were further pharmacomodulated to obtain a better activity against the AcrAB producing bacteria. PMID:27199950

  5. A tunable dual-wavelength pump source based on simulated polariton scattering for terahertz-wave generation

    NASA Astrophysics Data System (ADS)

    Sun, Bo; Liu, Jinsong; Yao, Jianquan; Li, Enbang

    2013-11-01

    We propose a dual-wavelength pump source by utilizing stimulated polariton scattering in a LiNbO3 crystal. The residual pump and the generated tunable Stokes waves can be combined to generate THz-wave generation via difference frequency generation (DFG). With a pump energy of 49 mJ, Stokes waves with a tuning range from 1067.8 to 1074 nm have been generated, and an output energy of up to 14.9 mJ at 1070 nm has been achieved with a conversion efficiency of 21.7%. A sum frequency generation experiment was carried out to demonstrate the feasibility of the proposed scheme for THz-wave DFG.

  6. LMFBR with booster pump in pumping loop

    DOEpatents

    Rubinstein, H.J.

    1975-10-14

    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.

  7. Prediction of performance of centrifugal pumps during starts under pressure

    NASA Technical Reports Server (NTRS)

    Rostafinski, W.

    1969-01-01

    Method which calculates start-up characteristics of centrifugal pumps reveals a capacity to predict pressure drop characteristics of pumps with vaned diffusers. Calculations are based on pump geometry, design-point flow, speed, and pressure rise, and the pump characteristic within range of approximately ten percent of the design-point flow.

  8. Liquid metal pump

    DOEpatents

    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.

  9. Winding for linear pump

    DOEpatents

    Kliman, G.B.; Brynsvold, G.V.; Jahns, T.M.

    1989-08-22

    A winding and method of winding for a submersible linear pump for pumping liquid sodium are disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet. 4 figs.

  10. Winding for linear pump

    DOEpatents

    Kliman, Gerald B.; Brynsvold, Glen V.; Jahns, Thomas M.

    1989-01-01

    A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.

  11. Evaluation of platelet damage in two different centrifugal pumps based on measurements of alpha-granule packing proteins.

    PubMed

    Mohara, J; Kawahito, K; Misawa, Y; Fuse, K

    1998-05-01

    Mechanical trauma caused by centrifugal pumps is usually evaluated in terms of hemolysis. However, platelet damage caused by centrifugal pumps has not been studied well. We evaluated platelet damage in 2 different centrifugal pumps, the Medtronic BioMedicus BP-80 and the Terumo Capiox, in vitro and compared the results in terms of hemolysis. To evaluate platelet damage, the rate of increase (RI) for beta-thromboglobulin (beta-TG) and platelet factor-4 (PF-4) were measured by enzyme immunoassay. RI was defined as follows: RI for beta-TG is deltabeta-TG/deltaN and RI for PF-4 is deltaPF-4/deltaN where deltabeta-TG is the increase in beta-TG, deltaPF-4 is the increase in PF-4, and deltaN is the increase of the passing number, which is defined in the following equation: N = Qt/V (t, time; V, priming volume; Q, flow rate). Each pump was tested in a mock circuit for 3 h under a flow rate of 5 L/min and a pressure head of 100 mm Hg using fresh human heparinized blood (n = 5). For comparison, the normalized index of hemolysis (NIH) values were calculated for both pumps. The NIH values did not indicate a significant difference between the Capiox and the BP-80 pumps (Capiox vs. BP-80, 0.0021 +/- 0.0004 vs. 0.0034 +/- 0.0007, NS). However, the RI values for beta-TG and PF-4 in the Capiox were significantly lower than in the BP-80 (beta-TG, 0.198 +/- 0.047 vs. 0.376 +/- 0.049; PF-4, 0.080 +/- 0.014 vs. 0.268 +/- 0.043, p < 0.05). In conclusion, although there was no significant difference between the 2 pumps in terms of hemolysis, the Capiox centrifugal pump induced less platelet damage than the BP-80. The results suggest that measurements of RI for beta-TG and PF-4 are more sensitive parameters than NIH values for evaluating blood cell damage.

  12. A finite-element-based perturbation model for the rotordynamic analysis of shrouded pump impellers: Part 2: User's guide

    NASA Technical Reports Server (NTRS)

    Baskharone, Erian A.

    1993-01-01

    This report describes the computational steps involved in executing a finite-element-based perturbation model for computing the rotor dynamic coefficients of a shrouded pump impeller or a simple seal. These arise from the fluid/rotor interaction in the clearance gap. In addition to the sample cases, the computational procedure also applies to a separate category of problems referred to as the 'seal-like' category. The problem, in this case, concerns a shrouded impeller, with the exception that the secondary, or leakage, passage is totally isolated from the primary-flow passage. The difference between this and the pump problem is that the former is analytically of the simple 'seal-like' configuration, with two (inlet and exit) flow-permeable stations, while the latter constitutes a double-entry / double-discharge flow problem. In all cases, the problem is that of a rotor clearance gap. The problem here is that of a rotor excitation in the form of a cylindrical whirl around the housing centerline for a smooth annular seal. In its centered operation mode, the rotor is assumed to give rise to an axisymmetric flow field in the clearance gap. As a result, problems involving longitudinal or helical grooves, in the rotor or housing surfaces, go beyond the code capabilities. Discarding, for the moment, the pre- and post-processing phases, the bulk of the computational procedure consists of two main steps. The first is aimed at producing the axisymmetric 'zeroth-order' flow solution in the given flow domain. Detailed description of this problem, including the flow-governing equations, turbulence closure, boundary conditions, and the finite-element formulation, was covered by Baskharone and Hensel. The second main step is where the perturbation model is implemented, with the input being the centered-rotor 'zeroth-order' flow solution and a prescribed whirl frequency ratio (whirl frequency divided by the impeller speed). The computational domain, in the latter case, is treated

  13. Gate-voltage controlled spin pumping effects: spin injection from YIG and Co into metal and graphene based 2 D materials

    NASA Astrophysics Data System (ADS)

    Kalitsov, Alan; Chshiev, Mairbek; Mryasov, Oleg

    2015-03-01

    Spin current injection into nonmagnetic metals, semiconductors and oxides is crucial component of spintronics. The spin pumping mechanism free from the impedance mismatch is a promising way to inject spin current into nonmagnetic materials. Here we present theory of spin current injected into non-magnetic films which arises from magnetization precession. We apply this theory to two cases (i) insulating yttrium iron garnet ferromagnet/nonmagnetic metal interfaces and (ii) hcp-Co/single layer graphene interface. The electron transport calculations are based on the non-equilibrium Green Function formalism within the tight binding Hamiltonian model. We show that magnitude of the pumped spin current can be efficiently controlled by the gate voltage.

  14. Derivation of a reflectogram using digital lock-in detection in coherent FMCW reflectometry based on a uniformly pumped Brillouin grating

    NASA Astrophysics Data System (ADS)

    Takada, Kazumasa; Yasuno, Takahiro

    2016-12-01

    We used digital lock-in detection to demodulate in-phase and quadrature components from a balanced mixer output in coherent FMCW reflectometry based on a uniformly pumped Brillouin grating. All the frequency components contributing to a reflectogram were extracted without attenuation by using a rectangular window in the frequency domain. We succeeded in reshaping a deformed reflectogram into a step-wise reflectogram for a single mode fiber that consisted of two fibers with different Brillouin frequencies. We found multiplicative noise to be dominant in the retrieved reflectograms, whose signal levels typically varied between ±7 and ±10%. We compared the observed changes with those estimated from power fluctuations in the amplified probe and pump light waves.

  15. Computational fluid dynamics-based hydraulic and hemolytic analyses of a novel left ventricular assist blood pump.

    PubMed

    Yang, Xiao-Chen; Zhang, Yan; Gui, Xing-Min; Hu, Sheng-Shou

    2011-10-01

    The advent of various technologies has allowed mechanical blood pumps to become more reliable and versatile in recent decades. In our study group, a novel structure of axial flow blood pump was developed for assisting the left ventricle. The design point of the left ventricular assist blood pump 25 (LAP-25) was chosen at 4 Lpm with 100 mm Hg according to our clinical practice. Computational fluid dynamics was used to design and analyze the performance of the LAP-25. In order to obtain a required hydraulic performance and a satisfactory hemolytic property in the LAP-25 of a smaller size, a novel structure was developed including an integrated shroud impeller, a streamlined impeller hub, and main impeller blades with splitter blades; furthermore, tandem cascades were introduced in designing the diffuser. The results of numerical simulation show the LAP-25 can generate flow rates of 3-5 Lpm at rotational speeds of 8500-10,500 rpm, producing pressure rises of 27.5-148.3 mm Hg with hydraulic efficiency points ranging from 13.4 to 27.5%. Moreover, the fluid field and the hemolytic property of the LAP-25 were estimated, and the mean hemolysis index of the pump was 0.0895% with Heuser's estimated model. In conclusion, the design of the LAP-25 shows an acceptable result.

  16. Water Pump Development for the EVA PLSS

    NASA Technical Reports Server (NTRS)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design, fabricate, and test a preflight prototype pump for use in the Extravehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump will accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting noncondensable gas without becoming "air locked." The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the preflight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES will simulate the vacuum environment in which the flight pump will operate. Testing will verify that the pump meets design requirements for range of flow rates, pressure rise, power consumption, working fluid temperature, operating time, and restart capability. Pump testing is currently

  17. A computer controlled pulsatile pump: preliminary study.

    PubMed

    Zwarts, M S; Topaz, S R; Jones, D N; Kolff, W J

    1996-12-01

    A Stepper Motor Driven Reciprocating Pump (SDRP) can replace roller pumps and rotary pumps for cardio pulmonary bypass, hemodialysis and regional perfusion. The blood pumping ventricles are basically the same as ventricles used for air driven artificial hearts and ventricular assist devices. The electric stepper motor uses a flexible linkage belt to produce a reciprocating movement, which pushes a hard sphere into the diaphragm of the blood ventricles. The SDRP generates pulsatile flow and has a small priming volume. The preset power level of the motor driver limits the maximum potential outflow pressure, so the driver acts as a safety device. A double pump can be made by connecting two fluid pumping chambers to opposing sides of the motor base. Each pump generates pulsatile flow. Pressure and flow studies with water were undertaken. Preliminary blood studies showed low hemolysis, even when circulating a small amount of blood up to 16 hours.

  18. Hydraulic pump

    SciTech Connect

    Polak, P.R.; Jantzen, D.E.

    1984-05-15

    This invention relates to an improved pump jack characterized by a hollow piston rod which telescopes down over the sucker rod to which it is clamped for reciprocating motion. The cylinder, in turn, is fastened in fixed position directly to the upper exposed end of the well casing. As fluid is introduced into the lower end of the cylinder it raises the piston into engagement with a pushrod housed in the upper cylinder head that lifts switch-actuating means associated therewith into a position operative to actuate a switch located adjacent thereto thereby causing the latter to change state and actuate a multi-function solenoid valve so as to cut off fluid flow to the cylinder. As gravity lowers the sucker rod and piston exhausting the hydraulic fluid therebeneath, an adjustable stop engages the pushrod from above so as to return it together with the switch-actuating means associated therewith to their original positions thereby resetting the switch to complete the operating cycle.

  19. Stirling Engine Heat Pump

    NASA Astrophysics Data System (ADS)

    Kagawa, Noboru

    Recent advances in the feasibility studies related to the Stirling engines and Stirling engine heat pumps which have been considered attractive due to their promising role in helping to solve the global environmental and energy problems,are reviewed. This article begins to describe the brief history of the Stirling engines and theoretical thermodynamic analysis of the Stirling cycle in order to understand several advantages on the Stirling engine. Furthermore,they could throw light on our question why the dream engines had not been promoted to practical applications during two hundred years. The present review shows that the Stirling engines with several unique advantages including 30 to 40% thermal efficiency and preferable exhaust characteristics,had been designed and constructed by recent tackling for the development of the advanced automobile and other applications using them. Based on the current state of art,it is being provided to push the Stirling engines combined with heat pumps based on the reversed Rankine cycle to the market. At present,however, many problems, especially for the durability, cost, and delicate engine parts must be enforced to solve. In addition,there are some possibilities which can increase the attractiveness of the Stirling engines and heat pumps. The review closes with suggestions for further research.

  20. Development of a miniaturized mass-flow meter for an axial flow blood pump based on computational analysis.

    PubMed

    Kosaka, Ryo; Nishida, Masahiro; Maruyama, Osamu; Yamane, Takashi

    2011-09-01

    In order to monitor the condition of patients with implantable left ventricular assist systems (LVAS), it is important to measure pump flow rate continuously and noninvasively. However, it is difficult to measure the pump flow rate, especially in an implantable axial flow blood pump, because the power consumption has neither linearity nor uniqueness with regard to the pump flow rate. In this study, a miniaturized mass-flow meter for discharged patients with an implantable axial blood pump was developed on the basis of computational analysis, and was evaluated in in-vitro tests. The mass-flow meter makes use of centrifugal force produced by the mass-flow rate around a curved cannula. An optimized design was investigated by use of computational fluid dynamics (CFD) analysis. On the basis of the computational analysis, a miniaturized mass-flow meter made of titanium alloy was developed. A strain gauge was adopted as a sensor element. The first strain gauge, attached to the curved area, measured both static pressure and centrifugal force. The second strain gauge, attached to the straight area, measured static pressure. By subtracting the output of the second strain gauge from the output of the first strain gauge, the mass-flow rate was determined. In in-vitro tests using a model circulation loop, the mass-flow meter was compared with a conventional flow meter. Measurement error was less than ±0.5 L/min and average time delay was 0.14 s. We confirmed that the miniaturized mass-flow meter could accurately measure the mass-flow rate continuously and noninvasively.

  1. Whole blood pumping with a microthrottle pump

    PubMed Central

    Davies, M. J.; Johnston, I. D.; Tan, C. K. L.; Tracey, M. C.

    2010-01-01

    We have previously reported that microthrottle pumps (MTPs) display the capacity to pump solid phase suspensions such as polystyrene beads which prove challenging to most microfluidic pumps. In this paper we report employing a linear microthrottle pump (LMTP) to pump whole, undiluted, anticoagulated, human venous blood at 200 μl min−1 with minimal erythrocyte lysis and no observed pump blockage. LMTPs are particularly well suited to particle suspension transport by virtue of their relatively unimpeded internal flow-path. Micropumping of whole blood represents a rigorous real-world test of cell suspension transport given blood’s high cell content by volume and erythrocytes’ relative fragility. A modification of the standard Drabkin method and its validation to spectrophotometrically quantify low levels of erythrocyte lysis by hemoglobin release is also reported. Erythrocyte lysis rates resulting from transport via LMTP are determined to be below one cell in 500 at a pumping rate of 102 μl min−1. PMID:21264059

  2. Transient two-phase performance of LOFT reactor coolant pumps

    SciTech Connect

    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.

  3. Multiple pump housing

    DOEpatents

    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.

  4. Types of Breast Pumps

    MedlinePlus

    ... Powered and Electric Pumps A powered breast pump uses batteries or a cord plugged into an electrical outlet ... pumps rely on a power source, women who use powered breast pumps should be prepared for emergency situations when electricity or extra batteries may not be available. If breastfeeding is not ...

  5. Method for controlling powertrain pumps

    DOEpatents

    Sime, Karl Andrew; Spohn, Brian L; Demirovic, Besim; Martini, Ryan D; Miller, Jean Marie

    2013-10-22

    A method of controlling a pump supplying a fluid to a transmission includes sensing a requested power and an excess power for a powertrain. The requested power substantially meets the needs of the powertrain, while the excess power is not part of the requested power. The method includes sensing a triggering condition in response to the ability to convert the excess power into heat in the transmission, and determining that an operating temperature of the transmission is below a maximum. The method also includes determining a calibrated baseline and a dissipation command for the pump. The calibrated baseline command is configured to supply the fluid based upon the requested power, and the dissipation command is configured to supply additional fluid and consume the excess power with the pump. The method operates the pump at a combined command, which is equal to the calibrated baseline command plus the dissipation command.

  6. Diode pumped tunable lasers based on Tm:CaF2 and Tm:Ho:CaF2 ceramics

    NASA Astrophysics Data System (ADS)

    Šulc, Jan; Němec, Michal; Jelinková, Helena; Doroshenko, Maxim E.; Fedorov, Pavel P.; Osiko, Vyacheslav V.

    2014-02-01

    The Tm:CaF2 (4% of TmF3) and Tm:Ho:CaF2 (2% of TmF3, 0.3% of HoF3) ceramics, prepared using hot pressing, and hot formation technique had been used as an active medium of diode pumped mid-infrared tunable laser. A fibre (core diameter 400 μm, NA = 0.22) coupled laser diode (LIMO, HLU30F400-790) was used to longitudinal pumping. The laser diode was operating in the pulsed regime (6 ms pulse length, 10 Hz repetition rate). The duty-cycle 6% ensures a low thermal load even under the maximum diode pumping power amplitude 25W (ceramics samples were only air-cooled). The laser diode emission wavelength was 786 nm. The 80mm long semi-hemispherical laser resonator consisted of a flat pumping mirror (HR @ 1.85 - 2.15 μm, HT @ 0.78 μm) and a curved (r = 150mm) output coupler with a reflectivity of ˜ 98% @ 1.85 - 2.0 μm for Tm:CaF2 laser or ˜ 99.5% @ 2.0 - 2.15 μm for Ho:Tm:CaF2. Tuning of the laser was accomplished by using a birefringent filter (single 1.5mm thick quartz plate) placed inside the optical resonator at the Brewster angle. Both samples offered broad and smooth tuning possibilities in mid-IR spectral range and the lasers were continuously tunable over ˜ 100 nm. The obtained Tm:CaF2 tunability ranged from 1892 to 1992nm (the maximum output energy 1.8mJ was reached at 1952nm for absorbed pumping energy 78 mJ). In case of Tm:Ho:CaF2 laser tunability from 2016 to 2111nm was reached (the maximum output energy 1.5mJ was reached at 2083nm for absorbed pumping energy 53 mJ). Both these material are good candidates for a future investigation of high energy, ultra-short, laser pulse generation.

  7. All-photonic switching based on selective input pump polarization states in Fe-doped PbS/PVA freestanding nanocomposite films

    NASA Astrophysics Data System (ADS)

    Rahma, M. A.; Saadon, H. L.; Mahdi, M. A.

    2017-04-01

    A new optical pump–probe technique for all-optical switching is proposed based on three-selective input pump polarization states to pump material simultaneously. The new technique makes it possible to obtain efficient all-optical switching of nonlinear optical materials with very low signal background and increased stability of switching signals. Undoped and Fe-doped PbS/PVA freestanding nanocomposite films are prepared by a simple chemical method at different doping concentrations. The x-ray diffraction patterns and optical absorption spectra of the prepared films are examined. The crystallinity and optical band gap of the prepared Fe-PbS/PVA are found to be affected by Fe doping concentration. The all-optical switching effect of Fe-PbS/PVA freestanding nanocomposite films with various Fe concentrations was investigated. The proposed technique that demonstrates all-optical switching with three-input polarization states can lead to the realization of all-photonic switching at a threshold optical pump power of 19 mW with maximum modulation depth (ON/OFF) of 86% and switching contrast (ON/OFF) of 8.6 dB for a minimum switching time of 43 ms.

  8. Pump-tuned deep-infrared femtosecond optical parametric oscillator across 6-7  μm based on CdSiP2.

    PubMed

    Chaitanya Kumar, S; Esteban-Martin, A; Santana, A; Zawilski, K T; Schunemann, P G; Ebrahim-Zadeh, M

    2016-07-15

    We report on a high-power femtosecond optical parametric oscillator (OPO) at 80 MHz repetition rate, tunable across 6318-7061 nm in the deep-infrared (deep-IR) using pump wavelength tuning. The OPO, based on CdSiP2 (CSP), is synchronously pumped by a commercial Ti:sapphire-pumped femtosecond OPO in the near-IR, enabling rapid static tuning of the CSP OPO with minimal adjustments to its cavity length. The deep-IR CSP OPO provides as much as 32 mW of average idler power at 6808 nm with spectral bandwidth >1000  nm (at -10  dB level) across the tuning range. By implementing intracavity dispersion control, near-transform-limited signal pulses of ∼100  fs duration with smooth single-peak spectrum are achieved at 1264 nm, corresponding to an idler wavelength at 6440 nm. To the best of our knowledge, this is the first time such practical idler powers in the deep-IR have been generated from a dispersion-compensated CSP femtosecond OPO at sub-100 MHz repetition rate.

  9. PIV Measurements in Pumps

    DTIC Science & Technology

    2006-11-01

    Pump Impeller Fig. 37 shows the top view of pump test rig for radial impeller pumps . The goal of this experiment is cavitation observation and their...PIV Measurements in Pumps 5 - 28 RTO-EN-AVT-143 Figure 37: Test Rig for Combined PIV Measurements and Cavitation Observation. Figure 38...RTO-EN-AVT-143 5 - 1 PIV Measurements in Pumps Dr. Detlev L. Wulff TU Braunschweig Institut für Strömungsmaschinen Langer Kamp 6 D-38106

  10. Paper pump for passive and programmable transport.

    PubMed

    Wang, Xiao; Hagen, Joshua A; Papautsky, Ian

    2013-01-01

    In microfluidic systems, a pump for fluid-driving is often necessary. To keep the size of microfluidic systems small, a pump that is small in size, light-weight and needs no external power source is advantageous. In this work, we present a passive, simple, ultra-low-cost, and easily controlled pumping method based on capillary action of paper that pumps fluid through conventional polymer-based microfluidic channels with steady flow rate. By using inexpensive cutting tools, paper can be shaped and placed at the outlet port of a conventional microfluidic channel, providing a wide range of pumping rates. A theoretical model was developed to describe the pumping mechanism and aid in the design of paper pumps. As we show, paper pumps can provide steady flow rates from 0.3 μl/s to 1.7 μl/s and can be cascaded to achieve programmable flow-rate tuning during the pumping process. We also successfully demonstrate transport of the most common biofluids (urine, serum, and blood). With these capabilities, the paper pump has the potential to become a powerful fluid-driving approach that will benefit the fielding of microfluidic systems for point-of-care applications.

  11. Paper pump for passive and programmable transport

    PubMed Central

    Wang, Xiao; Hagen, Joshua A.; Papautsky, Ian

    2013-01-01

    In microfluidic systems, a pump for fluid-driving is often necessary. To keep the size of microfluidic systems small, a pump that is small in size, light-weight and needs no external power source is advantageous. In this work, we present a passive, simple, ultra-low-cost, and easily controlled pumping method based on capillary action of paper that pumps fluid through conventional polymer-based microfluidic channels with steady flow rate. By using inexpensive cutting tools, paper can be shaped and placed at the outlet port of a conventional microfluidic channel, providing a wide range of pumping rates. A theoretical model was developed to describe the pumping mechanism and aid in the design of paper pumps. As we show, paper pumps can provide steady flow rates from 0.3 μl/s to 1.7 μl/s and can be cascaded to achieve programmable flow-rate tuning during the pumping process. We also successfully demonstrate transport of the most common biofluids (urine, serum, and blood). With these capabilities, the paper pump has the potential to become a powerful fluid-driving approach that will benefit the fielding of microfluidic systems for point-of-care applications. PMID:24403999

  12. Comparison of fiber lasers based on distributed side-coupled cladding-pumped fibers and double-cladding fibers.

    PubMed

    Huang, Zhihe; Cao, Jianqiu; Guo, Shaofeng; Chen, Jinbao; Xu, Xiaojun

    2014-04-01

    We compare both analytically and numerically the distributed side-coupled cladding-pumped (DSCCP) fiber lasers and double cladding fiber (DCF) lasers. We show that, through optimization of the coupling and absorbing coefficients, the optical-to-optical efficiency of DSCCP fiber lasers can be made as high as that of DCF lasers. At the same time, DSCCP fiber lasers are better than the DCF lasers in terms of thermal management.

  13. Alternative backing up pump for turbomolecular pumps

    DOEpatents

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  14. A compact spin-exchange optical pumping system for 3He polarization based on a solenoid coil, a VBG laser diode, and a cosine theta RF coil

    NASA Astrophysics Data System (ADS)

    Lee, Sungman; Kim, Jongyul; Moon, Myung Kook; Lee, Kye Hong; Lee, Seung Wook; Ino, Takashi; Skoy, Vadim R.; Lee, Manwoo; Kim, Guinyun

    2013-02-01

    For use as a neutron spin polarizer or analyzer in the neutron beam lines of the HANARO (High-flux Advanced Neutron Application ReactOr) nuclear research reactor, a 3He polarizer was designed based on both a compact solenoid coil and a VBG (volume Bragg grating) diode laser with a narrow spectral linewidth of 25 GHz. The nuclear magnetic resonance (NMR) signal was measured and analyzed using both a built-in cosine radio-frequency (RF) coil and a pick-up coil. Using a neutron transmission measurement, we estimated the polarization ratio of the 3He cell as 18% for an optical pumping time of 8 hours.

  15. Diode-pumped Nd:YVO4 laser emitting at 1074 nm based on the 4 F 3/2-4 I 11/2 transition

    NASA Astrophysics Data System (ADS)

    Ma, Z. Y.; Li, C. L.; Liang, W.; Wang, J. G.

    2011-09-01

    We report a diode-pumped Nd:YVO4 laser emitting at 1074 nm, based on the 4 F 3/2-4 I 11/2 transition, generally used for a 1064 nm emission. A power of 323 mW at 1074 nm has been achieved in continuouswave (CW) operation with a fiber-coupled laser diode emitting 18.2 W at 808 nm. Intracavity second-harmonic generation in CW mode has also been demonstrated with a power of 18 mW at 537 nm by using a LiB3O5 (LBO) nonlinear crystal.

  16. Pulsed electron-beam-pumped laser based on AlGaN/InGaN/GaN quantum-well heterostructure

    SciTech Connect

    Gamov, N A; Zhdanova, E V; Zverev, M M; Peregudov, D V; Studenov, V B; Mazalov, A V; Kureshov, V A; Sabitov, D R; Padalitsa, A A; Marmalyuk, A A

    2015-07-31

    The parameters of pulsed blue-violet (λ ≈ 430 nm at T = 300 K) lasers based on an AlGaN/InGaN/GaN structure with five InGaN quantum wells and transverse electron-beam pumping are studied. At room temperature of the active element, the minimum electron energy was 9 keV and the minimum threshold electron beam current density was 8 A cm{sup -2} at an electron energy of 18 keV. (lasers)

  17. An update on subsea multiphase pumping

    SciTech Connect

    Colombi, P.; De Donno, S.

    1996-02-01

    Agip SpA anticipates that subsea multiphase production, based on long-distance transportation of untreated oilwell fluids--namely, oil, water, and gas, will be an efficient tool for the exploitation of deepwater and marginal fields. In 1990, at the Trecate onshore oil field, Agip completed long-term testing of a multiphase screw pump, which confirmed commercial surface applications. Agip then integrated a subsea version of an improved multiphase twin-screw pump into a subsea multiphase boosting unit that was installed at the Prezioso field, offshore Sicily, in 1994 That was the first subsea installation of an electrically driven multi-phase pump operating with live oil. Agip began endurance testing of the pumping system in January 1995 and by last November, the cumulated period of running reached 3,500 hours with no evidence of pump-capacity reduction. Testing focused on boosting at high gas-void fraction and oil viscosity, operation at variable motor speed for pump control, pump control by means of throttling valves, direct interaction of the pumping system with both wells and the multiphase export line, variation of the lube-oil pressure across seals and bearings, and the evaluation of any degradation effect on the pump flow capacity over time. This paper reviews the design and performance of this pump and applicability to other offshore projects.

  18. Optimal quantum pumps.

    PubMed

    Avron, J E; Elgart, A; Graf, G M; Sadun, L

    2001-12-03

    We study adiabatic quantum pumps on time scales that are short relative to the cycle of the pump. In this regime the pump is characterized by the matrix of energy shift which we introduce as the dual to Wigner's time delay. The energy shift determines the charge transport, the dissipation, the noise, and the entropy production. We prove a general lower bound on dissipation in a quantum channel and define optimal pumps as those that saturate the bound. We give a geometric characterization of optimal pumps and show that they are noiseless and transport integral charge in a cycle. Finally we discuss an example of an optimal pump related to the Hall effect.

  19. Novel limiter pump topologies

    SciTech Connect

    Schultz, J.H.

    1981-01-01

    The use of limiter pumps as the principle plasma exhaust system of a magnetic confinement fusion device promises significant simplification, when compared to previously investigating divertor based systems. Further simplifications, such as the integration of the exhaust system with a radio frequency heating system and with the main reactor shield and structure are investigated below. The integrity of limiters in a reactor environment is threatened by many mechanisms, the most severe of which may be erosion by sputtering. Two novel topolgies are suggested which allow high erosion without limiter failure.

  20. Diode-pumped mode-locked Tm:LuAG laser at 2  μm based on GaSb-SESAM.

    PubMed

    Luan, C; Yang, K; Zhao, J; Zhao, S; Li, T; Zhang, H; He, J; Song, L; Dekorsy, T; Guina, M; Zheng, L

    2017-02-15

    Mode-locking of a directly diode-pumped Tm:LuAG laser is demonstrated using GaSb-based semiconductor saturable absorber mirrors (SESAMs). Stable and self-starting mode-locked operation was realized, generating pulses as short as 13.6 ps at 2024 nm with a maximum output power of 98 mW. Two GaInAs-based SESAMs were used for comparison with the operation based upon the use of the GaSb SESAM; in this case, longer pulses with durations of 27 ps and 34 ps were obtained under the same experimental conditions. Our work sets a new record in pulse duration for mode-locked Tm:LuAG lasers and confirms that lattice-matched GaSb-based SESAMs are beneficial for mode-locked solid-state lasers in the 2 μm range.

  1. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, M.; Ward, R.L.

    1991-12-24

    This patent describes a fluid sampling pump for withdrawing pressurized sample fluid from a flow line and for pumping a preselected quantity of sample fluid with each pump driving stroke from the pump to a sample vessel, the sampling pump including a pump body defining a pump bore therein having a central axis, a piston slideably moveable within the pump bore and having a fluid inlet end and an opposing operator end, a fluid sample inlet port open to sample fluid in the flow line, a fluid sample outlet port for transmitting fluid from the pump bore to the sample vessel, and a line pressure port in fluid pressure sample fluid in the flow line, an inlet valve for selectively controlling sample fluid flow from the flow line through the fluid sample inlet port, an operator unit for periodically reciprocating the piston within the pump bore, and a controller for regulating the stroke of the piston within the pump bore, and thereby the quantity of fluid pumped with each pump driving stroke. It comprises a balanced check valve seat; a balanced check valve seal; a compression member; and a central plunger.

  2. Bases for time-resolved probing of transient carrier dynamics by optical pump-probe scanning tunneling microscopy.

    PubMed

    Yokota, Munenori; Yoshida, Shoji; Mera, Yutaka; Takeuchi, Osamu; Oigawa, Haruhiro; Shigekawa, Hidemi

    2013-10-07

    The tangled mechanism that produces optical pump-probe scanning tunneling microscopy spectra from semiconductors was analyzed by comparing model simulation data with experimental data. The nonlinearities reflected in the spectra, namely, the excitations generated by paired laser pulses with a delay time, the logarithmic relationship between carrier density and surface photovoltage (SPV), and the effect of the change in tunneling barrier height depending on SPV, were examined along with the delay-time-dependent integration process used in measurement. The optimum conditions required to realize reliable measurement, as well as the validity of the microscopy technique, were demonstrated for the first time.

  3. Controlling mode competition by tailoring the spatial pump distribution in a laser: a resonance-based approach.

    PubMed

    Cerjan, Alexander; Redding, Brandon; Ge, Li; Liew, Seng Fatt; Cao, Hui; Douglas Stone, A

    2016-11-14

    We introduce a simplified version of the steady-state ab initio laser theory for calculating the effects of mode competition in continuous wave lasers using the passive cavity resonances. This new theory harnesses widely available numerical methods that can efficiently calculate the passive cavity resonances, with negligible additional computational overhead. Using this theory, we demonstrate that the pump profile of the laser cavity can be optimized both for highly multi-mode and single-mode emission. An open source implementation of this method has been made available.

  4. Gas pump with movable gas pumping panels

    DOEpatents

    Osher, J.L.

    Apparatus for pumping gas continuously a plurality of articulated panels of getter material, each of which absorbs gases on one side while another of its sides is simultaneously reactivated in a zone isolated by the panels themselves from a working space being pumped.

  5. Patient-controlled analgesic infusion pumps.

    PubMed

    1988-05-01

    We evaluated 7 PCA infusion pumps from 7 manufacturers. The condition for acceptable use of 6 of the units is that they not be used at low volumes that could result in overinfusion from the stored volume when an occlusion is cleared. Our ratings and ranking are based primarily on safety, security, and overall ease of use. All pumps meet most accuracy, electrical safety, and performance criteria. Two of the pumps are suitable for ambulatory use but are not recommended for general hospital or home care bedside use. One of the pumps is totally disposable and nonelectronic. Purchasing decisions should also take into consideration the cost of disposables, application, and medication security.

  6. Proton pump inhibitors

    MedlinePlus

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  7. Sizing pumps for slurries

    SciTech Connect

    Akhtar, S.Z.

    1996-11-01

    Slurry characteristics have a significant impact on centrifugal pump performance. For instance, as particle size increases or the percent solids concentration increases, pump head and efficiency decrease. Therefore, before a slurry pump is selected, it is important to define the slurry characteristics as accurately as possible. The effect of the slurry characteristics on the head and efficiency of the centrifugal pump will be emphasized (the effect on flowrate is less significant). The effect of slurry characteristics is more predominant in smaller pumps (with smaller diameter impellers) than in larger pumps. The data and relationship between the various slurry parameters have been developed from correlations and nomographs published by pump vendors from their field data and test results. The information helps to avoid specifying an undersized pump/motor assembly for slurry service.

  8. Insulin pump (image)

    MedlinePlus

    The catheter at the end of the insulin pump is inserted through a needle into the abdominal ... with diabetes. Dosage instructions are entered into the pump's small computer and the appropriate amount of insulin ...

  9. Liquid metal enabled pump

    PubMed Central

    Tang, Shi-Yang; Khoshmanesh, Khashayar; Sivan, Vijay; Petersen, Phred; O’Mullane, Anthony P.; Abbott, Derek; Mitchell, Arnan; Kalantar-zadeh, Kourosh

    2014-01-01

    Small-scale pumps will be the heartbeat of many future micro/nanoscale platforms. However, the integration of small-scale pumps is presently hampered by limited flow rate with respect to the input power, and their rather complicated fabrication processes. These issues arise as many conventional pumping effects require intricate moving elements. Here, we demonstrate a system that we call the liquid metal enabled pump, for driving a range of liquids without mechanical moving parts, upon the application of modest electric field. This pump incorporates a droplet of liquid metal, which induces liquid flow at high flow rates, yet with exceptionally low power consumption by electrowetting/deelectrowetting at the metal surface. We present theory explaining this pumping mechanism and show that the operation is fundamentally different from other existing pumps. The presented liquid metal enabled pump is both efficient and simple, and thus has the potential to fundamentally advance the field of microfluidics. PMID:24550485

  10. Interior, view of pumps looking at the north (window) and ...

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

    Interior, view of pumps looking at the north (window) and east walls, view to northwest - Ellsworth Air Force Base, Rushmore Air Force Station, Water Pump Station, Menoher Road, Blackhawk, Meade County, SD

  11. Simulation and experiment of pump distribution in LD end-pumped Nd:YAG single crystal fiber

    NASA Astrophysics Data System (ADS)

    Cai, XiaoTian; Li, Xiao; Zhao, GuoMin

    2017-01-01

    The spread of the pump model, established based on MATLAB, simulates the distribution of the pump in End-Pumped single crystal fiber. Simulation results show that the pump in the rod single crystal fiber will converge again. By changing the crystal absorption coefficient, it can be found that smaller the absorption coefficient is, more uniform the pump distribution is; when it is greater, the pump will concentrate to the pump end more seriously. Establish End- Pumped Experimental platform in the experiment, the crystal is 1 mm in diameter and length of 30 mm, Nd3+ doping concentration is 1%. Change the position of the pump light's focus in the crystal, we can see different distribution of the pump light by different focus location in the crystal and find that the pump light has the most homogeneous distribution when the focus is on the crystal axis and has 1mm distance to the pump end face. At this time, the second convergence of the pump is clearly visible. By changing the pump wavelength, crystal absorption coefficient changes. It is found that under the same pump power, absorption coefficient is greater, the pump will concentrate to the pump end more seriously. And the temperature of crystal pump end rises, which is identical with the simulation results. The results indicate that for the single crystal fiber, the higher absorption coefficient is not better, low absorption coefficient leads to the uniform distribution of the pump, there will be a better absorption in a relatively long length of single crystal fiber. And due to the lower end face temperature, end pump power upper limit will also increase.

  12. Photovoltaic pump systems

    NASA Astrophysics Data System (ADS)

    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.

  13. Rotary magnetic heat pump

    DOEpatents

    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.

  14. Rotary magnetic heat pump

    DOEpatents

    Kirol, Lance D.

    1988-01-01

    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.

  15. Centrifugal main fuel pump

    SciTech Connect

    Cole, E.F.

    1986-08-26

    For a gas turbine power plant having a fuel supply and a fuel metering valve and variable geometry for the power plant including servo actuating mechanisms for the fuel metering valve and variable geometry, a fuel pumping system, is described to supply pressurized fuel for the servo actuating mechanisms and for the engine working fluid medium. The pumping system includes a centrifugal pump solely supplying the fuel to the fuel metering valve to be delivered to the power plant for its working fluid medium, a positive displacement pump in parallel with the centrifugal pump and solely to supply pressurized fuel to the servo actuating mechanisms for the fuel metering valve and for the variable geometry, and a boost pump means disposed in serial relationship with the positive displacement pump and the centrifugal pump for augmenting the pressure supplied by the positive displacement pump and the centrifugal pump during predetermined operating conditions of the power plant. The combined boost pump and centrifugal pump capability is sufficient to satisfy the vapor to liquid ratio requirements of the power during its entire operating envelope.

  16. Green pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, Jerry W.; Brown, David C.

    2005-04-01

    Initial experiments with pulsed and CW pumping an alexandrite laser rod at 532 nm are presented. This pumping architecture holds promise for the production of scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  17. A "place n play" modular pump for portable microfluidic applications.

    PubMed

    Li, Gang; Luo, Yahui; Chen, Qiang; Liao, Lingying; Zhao, Jianlong

    2012-03-01

    This paper presents an easy-to-use, power-free, and modular pump for portable microfluidic applications. The pump module is a degassed particle desorption polydimethylsiloxane (PDMS) slab with an integrated mesh-shaped chamber, which can be attached on the outlet port of microfluidic device to absorb the air in the microfluidic system and then to create a negative pressure for driving fluid. Different from the existing monolithic degassed PDMS pumps that are generally restricted to limited pumping capacity and are only compatible with PDMS-based microfluidic devices, this pump can offer various possible configures of pumping power by varying the geometries of the pump or by combining different pump modules and can also be employed in any material microfluidic devices. The key advantage of this pump is that its operation only requires the user to place the degassed PDMS slab on the outlet ports of microfluidic devices. To help design pumps with a suitable pumping performance, the effect of pump module geometry on its pumping capacity is also investigated. The results indicate that the performance of the degassed PDMS pump is strongly dependent on the surface area of the pump chamber, the exposure area and the volume of the PDMS pump slab. In addition, the initial volume of air in the closed microfluidic system and the cross-linking degree of PDMS also affect the performance of the degassed PDMS pump. Finally, we demonstrated the utility of this modular pumping method by applying it to a glass-based microfluidic device and a PDMS-based protein crystallization microfluidic device.

  18. Problems identified with home infusion pumps.

    PubMed

    Koeppen, M A; Caspers, S M

    1994-01-01

    A variety of infusion pumps and devices are available on the market today. In this article, the authors examine these products based on questionnaires sent out to typical consumers, including hospitals and caregivers. Using the results of this questionnaire, the authors identify whether or not users of home infusion pumps and devices find them difficult to operate.

  19. 76 FR 34192 - Commercial and Industrial Pumps

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ... Economy (ACEEE) 2003 report ``Realizing Energy Efficiency Opportunities in Industrial Fan and Pump Systems... use. \\5\\ Nadel, S. and N. Elliot. ``Realizing Energy Efficiency Opportunities in Industrial Fan and..., ``Realizing Energy Efficiency 140.6 Opportunities in Industrial Fan and Pump Systems''.. Based on U.S....

  20. [Centrifugal blood pumps (new possibilities of design improvement)].

    PubMed

    Leshchinskiĭ, B M; Itkin, G P; Zimin, N K

    1992-01-01

    Based on an analysis of 300 world information sources, 19 types of centrifugal blood pumps were ascertained. Five new designs suggested have an idea in common: combination of the inlet of the disk pump and of the outlet of the impeller pump. This allows uniting the merits of the above pumps and excluding their shortcomings. The designs suggested make it possible to solve the two basic problems: hemolysis and thrombogenesis inside the pumps. The use of the pumps designed on such a basis will afford a simple and reliable approach to heart function replacement.

  1. Liquid metal electric pump

    DOEpatents

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1992-01-01

    An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other.

  2. Jet pump assisted artery

    NASA Technical Reports Server (NTRS)

    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.

  3. Absorption heat pump for space applications

    NASA Technical Reports Server (NTRS)

    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.

  4. Monitoring Non-Adiabatic Dynamics of the RNA Base Uracil by UV-Pump-IR-Probe Spectroscopy

    PubMed Central

    Fingerhut, Benjamin P.; Dorfman, Konstantin E.; Mukamel, Shaul

    2013-01-01

    Resolving the excited state dynamics of DNA- and RNA- nucleobases has attracted considerably attention. UV irradiation of the isolated nucleobases leads to the population of an electronic excited state which is quenched by internal conversion mediated by conical intersections on an ultrafast timescale. We present non-adiabatic on-the-fly molecular dynamics simulations of the UV-pump-IR-probe signal of the pyrimidine nucleobase uracil using a novel semiclassical protocol which takes into account the path integral over the excited state vibrational dynamics and properly describes the joint temporal and spectral resolution of the technique. Simulations of vibrational motions of carbonyl fingerprint modes in the electronically excited states reveal clear signatures of different relaxation pathways on a timescale of hundreds of femtoseconds which arise from an ultrafast branching in the excited state. We show that the inherent temporal and spectral resolution of the technique is not purely instrumental but also depends on the vibrational fluctuation timescale. PMID:23914288

  5. A miniaturized electrolytic pump sensorized with a strain gauge based on thermoplastic nanocomposite for drug delivery systems.

    PubMed

    Goffredo, R; Ferrone, A; Maiolo, L; Pecora, A; Accoto, D

    2015-01-01

    In this paper we present a miniature electrolytic pump sensorized with a novel strain sensor to be used as active component of a drug delivery system. It consists of an electrolytic solution reservoir where inert electrodes are immersed. By polarizing the electrodes, the electrolytic reaction is activated and the produced gases (i.e. oxygen and hydrogen) displace an elastic membrane delimiting the electrolytic solution reservoir. In order to measure and monitor the membrane displacement, and therefore the volume of drug ejected, a strain gauge sensor has been prepared using a conductive thermoplastic nanocomposite elastomer (CTPE). The sensor has been fixed on the deformable membrane. The conductive thermoplastic elastomer is a good candidate for this application because of its high sensitivity. Furthermore, the CTPE allows to customize the resistance of the device in order to obtain low power consumption.

  6. Nuclear pumped gas laser research

    NASA Technical Reports Server (NTRS)

    Thom, K.

    1976-01-01

    Nuclear pumping of lasers by fission-fragments from nuclear chain reactions is discussed. Application of the newly developed lasers to spacecraft propulsion or onboard power, to lunar bases for industrial processing, and to earth for utilization of power without pollution and hazards is envisioned. Emphasis is placed on the process by which the fission-fragement kinetic energy is converted into laser light.

  7. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, S.M.; Ward, R.L.

    1992-03-03

    This patent describes a pump for pumping a preselected quantity of fluid with each pump driving stroke from a fluid inlet port to a fluid outlet port, an inlet valve for selectively controlling fluid flow through the fluid inlet port, a pump body defining a pump bore therein, a piston slidably movable within the pump bore and having a fluid inlet end and an opposing operator end, an operator unit for reciprocating the piston within the pump bore, and a manifold interconnect with the pump body. It comprises a flow path therein extending from a manifold inlet port to a manifold outlet port, flow path being in communication with the fluid outlet port in the pump body, a purge passageway extending from the flow path to the outlet passageway, a purge valve for regulating fluid flow through the purge passageway, and a filter positioned within the manifold and extending across a portion of the flow path, the filter defining a filtered zone within the flow path adjoining the inlet port in the pump body, and an unfiltered zone within the flow path extending from the manifold inlet to the manifold outlet, such that filtered fluid enters the pump bore while unfiltered fluid bypasses the filter and passes out the manifold outlet port.

  8. Toward an ultra-broadband emission source based on the bismuth and erbium co-doped optical fiber and a single 830nm laser diode pump.

    PubMed

    Zhang, Jianzhong; Sathi, Zinat M; Luo, Yanhua; Canning, John; Peng, Gang-Ding

    2013-03-25

    We demonstrate a broadband optical emission from Bi/Er co-doped fiber and a single 830nm laser diode pump. The ultra-broadband mechanism is studied and discussed in details based on a combination of experimental measurements, including luminescence, differential luminescence and ESA, on fiber samples of different Bi and Er concentrations. The Er co-doping in Bi doped fiber is found to be effective for broadband emission, by enhancing not only luminescence at C and L bands but also that at O and shorter wavelength bands. The luminescence intensity between 1100 and 1570nm is over -45dBm/5nm in single mode fiber using a few meters of Bi/Er co-doped fiber and offers a modest ~40dB dynamic range and a broad bandwidth of ~470nm for an OSA based spectral measurement.

  9. Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

    NASA Technical Reports Server (NTRS)

    Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

    2009-01-01

    Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

  10. 11. VIEW SOUTH OF INTERIOR OF PUMP HOUSE NEAR SOUTHEAST ...

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

    11. VIEW SOUTH OF INTERIOR OF PUMP HOUSE NEAR SOUTHEAST CORNER OF BUILDING 7; PUMP WAS MOUNTED ON BASE AT CENTER OF PHOTO; PUMP WAS DRIVEN BY AN ELECTRIC MOTOR (STATOR REMAINS AT BOTTOM CENTER) AND COULD ALSO BE DRIVEN BY A TERRY STEAM TURBINE AT CENTER - Scovill Brass Works, 59 Mill Street, Waterbury, New Haven County, CT

  11. Pitot heat pump

    SciTech Connect

    Grose, R.D.

    1981-12-08

    A pitot heat pump is described wherein a multi-stage pitot pump is employed as the compression means in a heat pump thermodynamic cycle. The heat pump is comprised of a multi-stage vapor pitot pump, liquid pitot pump, turbine, vaporizer, evaporator, condenser and expansion valve. The turbine is used to rotate a shaft to which the impellers of the pitot pump are attached. Refrigerant gas from the evaporator enters the first stage of the pitot pump and the impeller therein forces the refrigerant gas outwardly where it enters the narrow end of a pitot tube provided therein. The discharge end of the pitot tube is in communication with the next stage of the pitot pump. In passing through the pitot tube, the refrigerant gas expands and the centrifugal force and the kinetic energy of the gas provide the energy whereby the refrigerant gas is compressed. After the last stage, the compressed gas is transmitted to the condenser of the heat pump.

  12. Electron pumping at gigahertz frequencies

    NASA Astrophysics Data System (ADS)

    Ritchie, David

    2010-03-01

    Recently, we have overcome the upper frequency limit measured for earlier pumps, by removing the reliance on quantum mechanical tunnelling through barriers on either side of a quantum dot [1]. The ease of operation, high frequency and simplicity of the waveform driving the pump were unexpected findings, contrary to previous predictions. The high speed (GHz), accurate pumping of electrons at the nano-Amp current level allows for easy integration in a wide range of applications from the development of the current standard in the field of metrology to single photon production and quantum based computing, making these new findings of value to many scientific disciplines. The inclusion of a perpendicular magnetic field [2] has shown a marked improvement in the accuracy of the pumped current and allows the study of the interactions of controlled dynamic electrons with a magnet field. Recent work combining two electron pumps in parallel [3] has demonstrated an increase in current output without the increase in error associated with a higher output current from a single pump. With the control and manipulation of a selected number of electrons there is the possibility of the creation of a two-particle entangled state. An interference-type experiment with the inclusion of a beam splitter could be used to probe this state. [4pt] [1] M. D. Blumenthal, B. Kaestner, L. Li, S. Giblin, T. J. B. M. Janssen, M. Pepper, D. Anderson, G. Jones, and D. A. Ritchie, Nature Physics 3, 343 (2007). [0pt] [2] S. J. Wright, M. D. Blumenthal, Godfrey Gumbs, A. L. Thorn, M. Pepper, T. J. B. M. Janssen, S. N. Holmes, D. Anderson, G. A. C. Jones, C. A. Nicoll, and D. A. Ritchie, Phys Rev B. 78, 233311 (2008). [0pt] [3] S. J. Wright, M. D. Blumenthal, M. Pepper, D. Anderson, G. A. C. Jones, C. A. Nicoll, and D. A. Ritchie, Phys Rev B. 80, 113303 (2009).

  13. A 2μm-pump laser-based DIRCM system and aero-optics in the mid-IR

    NASA Astrophysics Data System (ADS)

    Renz, Günther; Bohn, Willy

    2007-10-01

    The improvement of the security of platforms (aircrafts) with countermeasure techniques in the mid-IR especially in the take-off or landing phase is nowadays more stringent due to upcoming threats. We report on the development of a Tm:YLF-fiber laser (1.908 μm) pumped Ho:YAG (2.09 µm) high energy laser system with pulse energies up to 100 mJ at pulse lengths close to 20 ns and repetition rates of 100 Hz. A high quality laser beam leaving a platform through a variable-index-of-refraction airflow will experience wave-front aberrations and consequently lose its ability to be perfectly focused in the far field. Two main causes of laser beam degradations are issued in this investigation. First, there is the degradation immediately around the fuselage, referred to aero-optic problems and second the atmospheric propagation influence via air turbulence. The aero-optic influence on the laser beam degradation will be investigated in a laboratory experimental approach with a mid-IR laser beam traversing a transonic free air stream relevant to a real air flow around a fuselage. The propagation characteristics of a laser beam passing turbulent air will be numerically simulated with a multiple phase-screen method and a Fourier propagation technique. Different turbulence degrees relevant to propagation directions especially behind aircrafts will be considered.

  14. The impact of inlet angle and outlet angle of guide vane on pump in reversal based hydraulic turbine performance

    NASA Astrophysics Data System (ADS)

    Shi, F. X.; Yang, J. H.; Wang, X. H.; Zhang, R. H.; Li, C. E.

    2012-11-01

    In this paper, in order to research the impact of inlet angle and outlet angle of guide vane on hydraulic turbine performance, a centrifugal pump in reversal is adopted as turbine. A numerical simulation method is adopted for researching outer performance and flow field of turbine. The results show: inlet angle has a crucial role to turbine, to the same flow, there is a noticeable decline for the efficiency and head of turbine with the inlet angle increases. At the best efficiency point(EFP),to a same inlet angle, when the inlet angle greater than inlet angle, velocity circulation in guide vane outlet decreases, which lead the efficiency of turbine to reduce, Contrarily, the efficiency rises. With the increase of inlet angle and outlet angle, the EFP moves to the big flow area and the uniformity of pressure distribution becomes worse. The paper indicates that the inlet angle and outlet angle have great impact on the turbine performance, and the best combination exists for the inlet angle and outlet angle of the guide vane.

  15. Tunable femtosecond near-infrared source based on a Yb:LYSO-laser-pumped optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Wen-Long, Tian; Zhao-Hua, Wang; Jiang-Feng, Zhu; Zhi-Yi, Wei

    2016-01-01

    We demonstrate a widely tunable near-infrared source from 767 nm to 874 nm generated by the intracavity second harmonic generation (SHG) in an optical parametric oscillator pumped by a Yb:LYSO solid-state laser. The home-made Yb:LYSO oscillator centered at 1035 nm delivers an average power of 2 W and a pulse duration as short as 351 fs. Two MgO doped periodically poled lithium niobates (MgO:PPLN) with grating periods of 28.5-31.5 μm in steps of 0.5 μm and 19.5-21.3 μm in steps of 0.2 μm are used for the OPO and intracavity SHG, respectively. The maximum average output power of 180 mW at 798 nm was obtained and the output pulses have pulse duration of 313 fs at 792 nm if a sech2-pulse shape was assumed. In addition, tunable signal femtosecond pulses from 1428 nm to 1763 nm are also realized with the maximum average power of 355 mW at 1628 nm. Project supported by the National Key Basic Research Program of China (Grant No. 2013CB922402), the National Key Scientific Instruments Development Program of China (Grant No. 2012YQ120047), the National Natural Science Foundation of China (Grant Nos. 61205130 and 11174361), and the Key Deployment Project of Chinese Academy of Sciences (Grant No. KJZD-EW-L11-03).

  16. Cooling device for bradycardia based on Peltier element for accurate anastomosis of off-pump coronary artery bypass grafting.

    PubMed

    Kuniyoshi, Yukio; Koja, Kageharu; Miyagi, Kazufumi; Shimoji, Mituyoshi; Uezu, Tooru; Arakaki, Katuya; Yamashiro, Satoshi; Mabuni, Katuhito; Senaha, Shigenobu

    2002-10-01

    Upon introducing off-pump coronary artery bypass grafting (CABG), the indications for CABG were expanded to include patients who previously had no operative indications. For accurate anastomosis, various devices and methods have been developed. Bradycardia is easily induced by drug administration. However, this method of achieving bradycardia also has adverse effects on cardiac function. We have developed a new device to decrease the heart rate by regional cooling of the sino-atrial node. The new device is incorporated with Peltier's element, which uses an electric charge to create a temperature gradient on both of its surfaces. In terms of the cooling ability of this device, its cooling surface is chilled from 25 degrees C to 0 degrees C within 30 s. During in vivo animal experiments, this device has been shown to decrease the myocardial temperature around the sino-atrial node to 15 degrees C and suppress sino-atrial node activity, resulting in bradycardia to 60 beats/min level. In summary, the simple and easily applicable device for local cooling in combination with the application of diltiazem for effective heart rate reduction may be very helpful for the surgeon and may avoid disadvantages for critically ill patients.

  17. Preliminary conceptual design and weight of a one-megawatt space-based laser power station utilizing a solar-pumped iodine lasant

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

    1987-01-01

    A preliminary conceptual design of a space-based solar-pumped iodide laser emitting 1 MW of laser power for space-to-space power transmission is described. A near-parabolic solar collector focuses sunlight onto the t-C4F9I lasant within a transverse-flow optical cavity. Using waste heat, a thermal system supplies compressor and auxiliary power. The major system components are designed with weight estimates assigned. In particular, it is found that laser efficiency is not a dominant weight factor, the dominant factor being the laser transmission optics. The station mass is 92,000 kg, requiring approximately eight Shuttle flights to LEO, where an orbital transfer vehicle can transport it to the final altitude of 6378 km.

  18. Ultra-low phase-noise microwave generation using a diode-pumped solid-state laser based frequency comb and a polarization-maintaining pulse interleaver.

    PubMed

    Portuondo-Campa, Erwin; Buchs, Gilles; Kundermann, Stefan; Balet, Laurent; Lecomte, Steve

    2015-12-14

    We report ultra-low phase-noise microwave generation at a 9.6 GHz carrier frequency from optical frequency combs based on diode-pumped solid-state lasers emitting at telecom wavelength and referenced to a common cavity-stabilized continuous-wave laser. Using a novel fibered polarization-maintaining pulse interleaver, a single-oscillator phase-noise floor of -171 dBc/Hz at 10 MHz offset frequency has been measured with commercial PIN InGaAs photodiodes, constituting a record for this type of detector. Also, a direct optical measurement of the stabilized frequency combs' timing jitter was performed using a balanced optical cross correlator, allowing for an identification of the origin of the phase-noise limitations in the system.

  19. A high-repetition rate scheme for synchrotron-based picosecond laser pump/x-ray probe experiments on chemical and biological systems in solution.

    PubMed

    Lima, Frederico A; Milne, Christopher J; Amarasinghe, Dimali C V; Rittmann-Frank, Mercedes Hannelore; van der Veen, Renske M; Reinhard, Marco; Pham, Van-Thai; Karlsson, Susanne; Johnson, Steven L; Grolimund, Daniel; Borca, Camelia; Huthwelker, Thomas; Janousch, Markus; van Mourik, Frank; Abela, Rafael; Chergui, Majed

    2011-06-01

    We present the extension of time-resolved optical pump/x-ray absorption spectroscopy (XAS) probe experiments towards data collection at MHz repetition rates. The use of a high-power picosecond laser operating at an integer fraction of the repetition rate of the storage ring allows exploitation of up to two orders of magnitude more x-ray photons than in previous schemes based on the use of kHz lasers. Consequently, we demonstrate an order of magnitude increase in the signal-to-noise of time-resolved XAS of molecular systems in solution. This makes it possible to investigate highly dilute samples at concentrations approaching physiological conditions for biological systems. The simplicity and compactness of the scheme allows for straightforward implementation at any synchrotron beamline and for a wide range of x-ray probe techniques, such as time-resolved diffraction or x-ray emission studies.

  20. High average power, widely tunable femtosecond laser source from red to mid-infrared based on an Yb-fiber-laser-pumped optical parametric oscillator.

    PubMed

    Gu, Chenglin; Hu, Minglie; Zhang, Limeng; Fan, Jintao; Song, Youjian; Wang, Chingyue; Reid, Derryck T

    2013-06-01

    We report on the highly efficient generation of widely tunable femtosecond pulses based on intracavity second harmonic generation (SHG) and sum frequency generation (SFG) in a MgO-doped periodically poled LiNbO(3) optical parametric oscillator (OPO), which is pumped by a Yb-doped large-mode-area photonics crystal fiber femtosecond laser. Red and near infrared from intracavity SHG and SFG and infrared signals were directly obtained from the OPO. A 2 mm β-BaB(2)O(4) is applied for Type I (oo → e) intracavity SHG and SFG, and then femtosecond laser pulses over 610 nm ~ 668 nm from SFG and 716 nm ~ 970 nm from SHG are obtained with high efficiency. In addition, the oscillator simultaneously generates signal and idler femtosecond pulses over 1450 nm ~ 2200 nm and 2250 nm ~ 4000 nm, respectively.

  1. A high-repetition rate scheme for synchrotron-based picosecond laser pump/x-ray probe experiments on chemical and biological systems in solution

    SciTech Connect

    Lima, Frederico A.; Milne, Christopher J.; Amarasinghe, Dimali C. V.; Rittmann-Frank, Mercedes Hannelore; Veen, Renske M. van der; Reinhard, Marco; Pham, Van-Thai; Karlsson, Susanne; Mourik, Frank van; Chergui, Majed; Johnson, Steven L.; Grolimund, Daniel; Borca, Camelia; Huthwelker, Thomas; Janousch, Markus; Abela, Rafael

    2011-06-15

    We present the extension of time-resolved optical pump/x-ray absorption spectroscopy (XAS) probe experiments towards data collection at MHz repetition rates. The use of a high-power picosecond laser operating at an integer fraction of the repetition rate of the storage ring allows exploitation of up to two orders of magnitude more x-ray photons than in previous schemes based on the use of kHz lasers. Consequently, we demonstrate an order of magnitude increase in the signal-to-noise of time-resolved XAS of molecular systems in solution. This makes it possible to investigate highly dilute samples at concentrations approaching physiological conditions for biological systems. The simplicity and compactness of the scheme allows for straightforward implementation at any synchrotron beamline and for a wide range of x-ray probe techniques, such as time-resolved diffraction or x-ray emission studies.

  2. Optimization of a Raman/EDFA hybrid amplifier based on dual-order stimulated Raman scattering using a single-pump

    NASA Astrophysics Data System (ADS)

    Li, Zhaohui; Zhao, Chun-Liu; Wen, Yang Jing; Lu, Chao; Wang, Yixin; Chen, Jian

    2006-09-01

    Based on dual-order stimulated Raman scattering (SRS) of a single 1395 nm Raman fiber laser in 75 km single mode fiber and its corresponding dispersion compensation module, a hybrid Raman/Erbium doped fiber amplifier (EDFA) for long wavelength band (L-band) amplification is realized by inserting a segment of EDF within the span. By comparing the performance of gain and noise in four hybrid amplifiers with different span configurations, we find that the distribution of the secondary L-band amplification obtained from the EDF along the link has a great influence on the performance of the hybrid amplifier. Both gain and noise performance of hybrid amplifier can be improved significantly by optimizing the location of the EDF. Moreover, we can extend the flat gain bandwidth from L-band to central wavelength band (C-band) plus L-band by recycling the residual first-order SRS to pump a segment of EDF with proper length.

  3. Pump isolation valve

    DOEpatents

    Kinney, Calvin L.; Wetherill, Todd M.

    1983-08-02

    The pump isolation valve provides a means by which the pump may be selectively isolated from the remainder of the coolant system while being compatible with the internal hydraulic arrangement of the pump during normal operation of the pump. The valve comprises a valve cylinder disposed around the pump and adjacent to the last pump diffuser with a turning vane attached to the lower end of the valve cylinder in a manner so as to hydraulically match with the discharge diffuser. The valve cylinder is connected to a drive means for sliding the valve cylinder relative to the diffuser support cylinder so as to block flow in either direction through the discharge diffuser when the valve is in the closed position and to aid in the flow of the coolant from the discharge diffuser by means of the turning vane when the valve is in the open position.

  4. DIRECT CURRENT ELECTROMAGNETIC PUMP

    DOEpatents

    Barnes, A.H.

    1957-11-01

    An improved d-c electromagnetic pump is presented in which the poles, and consequently the magetic gap at the poles, are tapered to be wider at the upstream end. In addition, the cross section of the tube carryiQ the liquid metal is tapered so that the velocity of the pumped liquid increases in the downstream direction at a rate such that the counter-induced voltage in the liquid metal remains constant as it traverses the region between the poles. This configuration compensates for the distortion of the magnetic field caused by the induced voltage that would otherwise result in the lowering of the pumping capacity. This improved electromagnetic pump as practical application in the pumping of liquid metal coolants for nuclear reactors where conventional positive displacement pumps have proved unsatisfactory due to the high temperatures and the corrosive properties of the liquid metals involved.

  5. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J. (Inventor); Akkerman, James W. (Inventor); Aber, Greg S. (Inventor); Vandamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1993-01-01

    A rotary blood pump is presented. The pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial, and radial clearances of the blades associated with the flow straightener, inducer portion, impeller portion, and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with crosslinked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  6. Electrokinetic pumps and actuators

    SciTech Connect

    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.

  7. Trim or Replace Impellers on Oversized Pumps

    SciTech Connect

    Not Available

    2006-09-01

    normally be greater with a smaller impeller, but engineers should consult with the pump manufacturer to determine variations in NPSHR before trimming the impeller. Manufacturers can often provide trim correction charts based on historical test data.

  8. Axial and centrifugal pump meanline performance analysis

    NASA Technical Reports Server (NTRS)

    Veres, Joseph P.

    1994-01-01

    A meanline pump flow modeling method has been developed to provide a fast capability for modeling pumps of cryogenic rocket engines. Based on this method, a meanline pump flow code (PUMPA) has been written that can predict the performance of pumps at off-design operating conditions, given the loss of the diffusion system at the design point. The design point rotor efficiency is obtained from empirically derived correlations of loss to rotor specific speed. The rapid input setup and computer run time for the meanline pump flow code makes it an effective analysis and conceptual design tool. The map generation capabilities of the PUMPA code provide the information needed for interfacing with a rocket engine system modeling code.

  9. Identification of a solar pumping installation

    NASA Astrophysics Data System (ADS)

    Annabi, M.; Slama, N. B.; Kachoukh, M.; Ksouri, M.; Perard, J.

    1980-12-01

    The process identification of a solar pumping facility is discussed in view of its importance to pump power supply optimization. A method for process identification based on the measurement of the short circuit current, open circuit voltage and in-charge current and voltage of the photovoltaic cell in order to determine the cell illumination and junction temperature is presented, and the determination of pump efficiency from measurements of generator power and actual pumping power is indicated. An application of the method to the identification of the parameters of the Hendi Zitoun pumping station is presented. The optimization of generator power on the basis of the information gained from process identification is then illustrated by the use of a chopper-type static converter installed between the solar panel and the load to optimize the power supplied by providing a constant voltage at a constant junction temperature, and varying the voltage with the temperature.

  10. Fakir fuel pump

    NASA Technical Reports Server (NTRS)

    1922-01-01

    In designing the Fakir fuel pump, the fundamental idea was to obtain a simple and reliable method of conveying the fuel from a low tank to the carburetor, with the avoidance of the faults of all former methods and the simultaneous warming of the fuel by means of the heat of compression generated. The principle of the Fakir fuel pump rests on the well-known principle of the diaphragm pump, which must be suitably adapted to the present purpose.

  11. A compact cryogenic pump

    NASA Astrophysics Data System (ADS)

    Li, Gang; Caldwell, Shane; Clark, Jason A.; Gulick, Sidney; Hecht, Adam; Lascar, Daniel D.; Levand, Tony; Morgan, Graeme; Orford, Rodney; Savard, Guy; Sharma, Kumar S.; Van Schelt, Jonathon

    2016-04-01

    A centrifugal cryogenic pump has been designed at Argonne National Laboratory to circulate liquid nitrogen (LN2) in a closed circuit allowing the recovery of excess fluid. The pump can circulate LN2 at rates of 2-10 L/min, into a head of 0.5-3 m. Over four years of laboratory use the pump has proven capable of operating continuously for 50-100 days without maintenance.

  12. Detection of pump degradation

    SciTech Connect

    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.

  13. Multiphase rotodynamic pumps extend their operating capabilities

    SciTech Connect

    Falcimaigne, J.; Durando, P.; Loupias, M.; Vilagines, R.

    1994-12-31

    The paper describes the main features of the P302 multiphase pump and presents some results of bench tests carried out to check its hydraulic performances. The P302 is a rotodynamic helico-axial pump based on the Poseidon pumping technology. It is equipped with water lubricated bearings and driven by a high speed electrical motor. The pump was designed to work with a suction pressure much lower than the P300 prototype and to deliver a higher compression ratio. It has fifteen stages of compression cells, in three different series. Before installing the pump on an onshore production site for endurance tests with actual field fluids, the steady-state behavior and the transient responses of the pump were characterized on the IFP multiphase loop at Solaize (France). The pump was tested both with single phase fluids (liquid or gas) and a diphasic mixture (fuel-oil and nitrogen) at various GVF and suction pressures. In the paper, theoretical predictions are compared to measured data. The good results of these tests confirmed the soundness and versatility of the Poseidon hydraulics and also the calculation model ability to predict accurately the performances of rotodynamic pump over a wide range of operating conditions.

  14. Development of an implantable centrifugal blood pump.

    PubMed

    Goldstein, A H; Pacella, J J; Trumble, D R; Clark, R E

    1992-01-01

    The efficacy of centrifugal pumps for short-term (0-30 days) ventricular support has been widely reported and favorably compared with pulsatile systems. A small, durable, implantable centrifugal blood pump is being developed for medium-term use (up to 6 months). The pump is based on the Medtronic Hemadyne system that has existed in multiple forms over the past 30 years. The pump is approximately the size of a tennis ball, weighs 240 g, and is comprised of a 2.5 cm plastic impeller driven by a radially coupled brushless DC motor. In vitro hydraulic performance was recorded over a wide range of flow conditions on a mock circulatory loop. The pump generated 7 L/min flow against an afterload of 100 mmHg pressure, with a maximum power draw of 10.4 watts. Pulsatile flow was preserved when placed in conjunction with a simulated left ventricle. In vivo testing was performed in 10 healthy sheep for 10-292 hr. Heparin was used to facilitate cannulation, and no anticoagulation was administered after pump implantation. Blood chemistries reflecting hematologic, pulmonary, renal, and hepatic functions were recorded and demonstrated no adverse effects with normal pump operation. Complications were related to kinking of blood conduits and thrombus formation within the cannulae. These results are encouraging and warrant further studies to prove feasibility of this pump as a medium-term implantable ventricular assist device.

  15. Liquid-Metal Pump Technologies for Nuclear Surface Power

    NASA Technical Reports Server (NTRS)

    Polzin, K. A.

    2007-01-01

    Multiple liquid-metal pump options are reviewed for the purpose of determining the technologies that are best suited for inclusion in a nuclear reactor thermal simulator intended to test prototypical space nuclear system components. Conduction, induction, and thermoelectric electromagnetic pumps are evaluated based on their performance characteristics and the technical issues associated with incorporation into a reactor system. The thermoelectric pump is recommended for inclusion in the planned system at NASA MSFC based on its relative simplicity, low power supply mass penalty, flight heritage, and the promise of increased pump efficiency over earlier flight pump designs through the use of skutterudite thermoelectric elements.

  16. Submersible sodium pump

    DOEpatents

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  17. Submersible sodium pump

    DOEpatents

    Brynsvold, Glen V.; Lopez, John T.; Olich, Eugene E.; West, Calvin W.

    1989-01-01

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates.

  18. Fuel injection pump

    SciTech Connect

    Miyaki, M.

    1986-01-07

    This patent describes a fuel injection pump for delivering fuel to the cylinders of an internal combustion engine consisting of: a pump housing with a fuel chamber therein to which fuel is supplied from a fuel tank; means for compressing fuel in the pump chamber and delivering the compressed fuel to the engine cylinders with such means including a pump plunger adapted to be reciprocated so as to introduce fuel into the pump chamber and to pressurize the introduced fuel; spill means for spilling to a low-pressure side on a fuel tank side the compressed fuel which was pressurized in the pump chamber to be delivered from the pump chamber to the engine cylinders, the spill mechanism including a spill passage communicating with the pump chamber and including a solenoid valve located in the spill passage for opening and closing the spill passage with predetermined timing; escape for allowing the compressed fuel pressurized in the pump chamber to escape to the low-pressure side of the fuel tank side.

  19. Remotely operable peristaltic pump

    NASA Technical Reports Server (NTRS)

    Belew, R. R. (Inventor)

    1986-01-01

    A peristaltic pump is disclosed which includes a roller assembly on which is mounted a series of pump rollers. As the roller assembly is rotated by a drive gear the pump rollers are driven in reverse rotation by means of a stationary ring gear and pump roller gears. An upper pressure shoe plate and a lower pressure shoe plate are positioned above sets of flexible tubing. The tubing is sandwiched between the pressure shoe plates and the pump rollers. A highly compact pump is provided having twice as many fluid channel lines as is conventional. The peristaltic pump device may be remotely operated by means of a rotary actuator which rotates a driving hub to move the shoe plates by means of eccentrically mounted links. The pressure shoe plates may be moved by the rotary actuator to a loaded position in which the fluid lines are pinched by the pump rollers and fluid is pumped to an unloaded position in which the fluid lines are maintained in an undeformed, uncrimped configuration so that no creases or crimps are set into the fluid lines during periods of prolonged nonuse.

  20. Thermomechanical piston pump development

    NASA Technical Reports Server (NTRS)

    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.

  1. [Portable peristaltic perfusion pumps].

    PubMed

    Magallón Pedrera, I; Soto Torres, I

    1999-11-01

    Portable peristaltic perfusion pumps allow one to administer pharmaceuticals in hospitals as well as in primary health care centers and furthermore these pumps present multiple advantages for patients and their families since they make it possible to carry out treatment in a patient's home while at the same time lowering the costs involved. The authors analyze the most out standing aspects of portable peristaltic perfusion pumps along with their characteristics, installation, programming, and how to turn them on; in addition, the authors list the maintenance care which these pumps require.

  2. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1995-04-01

    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.

  3. Hydrodynamic design of generic pump components

    NASA Technical Reports Server (NTRS)

    Eastland, A. H. J.; Dodson, H. C.

    1991-01-01

    Inducer and impellar base geometries were defined for a fuel pump for a generic generator cycle. Blade surface data and inlet flowfield definition are available in sufficient detail to allow computational fluid dynamic analysis of the two components.

  4. Resonance wave pumping: wave mass transport pumping

    NASA Astrophysics Data System (ADS)

    Carmigniani, Remi; Violeau, Damien; Gharib, Morteza

    2016-11-01

    It has been previously reported that pinching at intrinsic resonance frequencies a valveless pump (or Liebau pump) results in a strong pulsating flow. A free-surface version of the Liebau pump is presented. The experiment consists of a closed tank with a submerged plate separating the water into a free-surface and a recirculation section connected through two openings at each end of the tank. A paddle is placed at an off-centre position at the free-surface and controlled in a heaving motion with different frequencies and amplitudes. Near certain frequencies identified as resonance frequencies through a linear potential theory analysis, the system behaves like a pump. Particle Image Velocimetry (PIV) is performed in the near free surface region and compared with simulations using Volume of Fluid (VOF) method. The mean eulerian mass flux field (ρ) is extracted. It is observed that the flow is located in the vicinity of the surface layer suggesting Stokes Drift (or Wave Mass Transport) is the source of the pumping. A model is developped to extend the linear potential theory to the second order to take into account these observations. The authors would like to acknowledge the Gordon and Betty Moore Foundation for their generous support.

  5. Particulate problem solutions for rod pumped producing wells

    SciTech Connect

    Williams, S.J.

    1995-12-31

    Sand and other fluid entrained particulates can cause substantial operational problems for rod pumped producing wells. These problems take the form of down-hole pump wear, plunger sticking, and/or catastrophic breakage of pump components. A six year study of 600+ pump investigations shows that problems with particulates account for a substantial number of the total barrel and plunger failures. Many of these failures could have been avoided through the proper application of API and special pump designs as well as certain choices of pump variables. These pump variables and designs will be addressed along with operating parameters. How hard is sand? How large is it? Should plunger and barrel choices take these variables into account? Also, metal plungers must {open_quotes}slip{close_quotes} fluid for proper lubrication. Too much slippage leads to pump inefficiencies. However, down-hole pump efficiencies based on slippage need to be balanced against pump longevity due to proper selection for particulate production. Some time-proven rules of thumb can be applied to make these choices, and an included chart will make plunger slippage calculations simple and straightforward. Scale which sticks to pump surfaces dictates the choice of a different style down-hole pump. A straight-forward modification of an RH style API pump has proved successful in these conditions. Fluid and particulate production with and without attendant gas production requires a different approach to down-hole pump selection. Several successful older pump designs as well as some recently proven new designs will be described. A test program has been completed and actual applications have shown that an API Tubing Pump derivative can pump large volumes of particulate laden fluid without characteristic sticking of the plunger.

  6. Well-pump alignment system

    DOEpatents

    Drumheller, Douglas S.

    1998-01-01

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping.

  7. Liquid pump for astronaut cooling

    NASA Technical Reports Server (NTRS)

    Carson, M. A.

    1972-01-01

    The Apollo portable life support system water-recirculation pump used for astronaut cooling is described. The problems associated with an early centrifugal pump and how these problems were overcome by the use of a new diaphragm pump are discussed. Performance comparisons of the two pump designs are given. Developmental problems and flight results with the diaphragm pump are discussed.

  8. METHOD FOR PUMPING GASES AT LOW VACUUM PRESSURES

    DOEpatents

    Milleron, N.

    1962-06-01

    A method is given for pumping overpressure "pulses" or "bursts" of gases without a significant rise in base pressure within a "gettering-type" vacuum pump having surfaces within the pumping cavity coated with or comprising clean gettering metal, e.g., Mo or Ta. The cavity is first pumped down by any convenient means to an equilibrium base pressure in the range desired, generally below 10/sup -6/ mm Hg. At this pressure, the metal immediately adsorbs overpressures or "bursts" of gases striking same with thermal motion without raising the base pressure significantiy. Desorption takes place at an equilibrium rate which, of course, is dependent upon the equilibrium pressure, and such desorbed gases are continuously removed by diffuaion pump or other pumping, whereby said overpressures or "bursts" of gases are removed without a rise in the equilibrium pressure and/or back diffusion of the gaseous pulse from the pumping cavity. (AEC)

  9. Looking south at boiler feedwater pumps (steam turbine pump on ...

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

    Looking south at boiler feedwater pumps (steam turbine pump on left, electric motor pump on right). - Wheeling-Pittsburgh Steel Corporation, Allenport Works, Boiler House, Route 88 on West bank of Monongahela River, Allenport, Washington County, PA

  10. 98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. ...

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

    98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. 2 IN FOREGROUND, ABANDONED BARREN SOLUTION PUMP BEYOND. AGITATOR No. 1 IN BACKGROUND. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  11. 33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING ...

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

    33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING PLAN AND LOCATION OF PROPOSED ADDITIONS, METROPOLITAN WATER AND SEWERAGE BOARD, METROPOLITAN SEWERAGE WORKS, JULY 1908. Aperture card 6417. - Deer Island Pumping Station, Boston, Suffolk County, MA

  12. Low socioeconomic status is associated with adverse events in children and teens on insulin pumps under a universal access program: a population-based cohort study

    PubMed Central

    Shulman, Rayzel; Stukel, Therese A; Miller, Fiona A; Newman, Alice; Daneman, Denis; Wasserman, Jonathan D; Guttmann, Astrid

    2016-01-01

    Objective To describe adverse events in pediatric insulin pump users since universal funding in Ontario and to explore the role of socioeconomic status and 24-hour support. Research design and methods Population-based cohort study of youth (<19 years) with type 1 diabetes (n=3193) under a universal access program in Ontario, Canada, from 2006 to 2013. We linked 2012 survey data from 33 pediatric diabetes centers to health administrative databases. The relationship between patient and center-level characteristics and time to first diabetic ketoacidosis (DKA) admission or death was tested using a Cox proportional hazards model and the rate of diabetes-related emergency department visits and hospitalizations with a Poisson model, both using generalized estimating equations. Results The rate of DKA was 5.28/100 person-years and mortality 0.033/100 person-years. Compared with the least deprived quintile, the risk of DKA or death for those in the most deprived quintile was significantly higher (HR 1.58, 95% CI 1.05 to 2.38) as was the rate of diabetes-related acute care use (RR 1.60, 95% CI 1.27 to 2.00). 24-hour support was not associated with these outcomes. Higher glycated hemoglobin, prior DKA, older age, and higher nursing patient load were associated with a higher risk of DKA or death. Conclusions The safety profile of pump therapy in the context of universal funding is similar to other jurisdictions and unrelated to 24-hour support. Several factors including higher deprivation were associated with an increased risk of adverse events and could be used to inform the design of interventions aimed at preventing poor outcomes in high-risk individuals. PMID:27547416

  13. Combining Satellite and Ground-Based Radar Interferometry Data to Measure Surface Deformation Associated with EGS Pumping Activities at Newberry Crater, OR Geothermal Site

    NASA Astrophysics Data System (ADS)

    Vincent, P.; Cladouhos, T. T.; Schultz, A.; Rose, K.; Urquhart, S.

    2013-12-01

    TerraSAR-X (TSX) satellite data are combined with data collected using a ground-based real aperture radar interferometer (GAMMA Remote Sensing AG Portable Radar Interferometer-2, GPRI2) to remotely image surface deformation arising from enhanced geothermal system (EGS) pumping activity at the geothermal site located off the western flank of Newberry Crater, OR. Due to the heavily forested area impeding the utility of interferometric measurements at X-band (TSX) and Ku-band (GPRI2) wavelengths, 100 aluminum radar corner reflectors (CRs) were fabricated and installed in pairs approximately 5-8 meters above the ground in 50 large trees for optimal visibility and wind stability. One CR in each pair was aimed up at the ascending orbit track look direction for TSX, and the other was simultaneously aimed at the descending orbit track look direction for TSX and to Paulina Peak 6 km to the southwest for line-of-sight to the GPRI2 antenna position. The combination of 11-day repeat orbit acquisitions from a near vertical look direction from TSX with on-demand (up to daily) acquisitions from a near horizontal look direction from the GPRI2 instrument allows for full 3D displacement vector determination for each target imaged. Standard and point-target processing techniques are used to maximize the utility of the data collected and the transient nature of the pumping activities and resulting surface deformation signals demand this high level of spatial-temporal sampling. Preliminary data quality and deformation signal results will be presented and put in context with well-log data such as pressure, volume and flow rate, as well as data from microseismic array, MT, and gravity surveys.

  14. High-power PPMgLN-based optical parametric oscillator pumped by a linearly polarized, semi-fiber-coupled acousto-optic Q-switched fiber master oscillator power amplifier.

    PubMed

    Chen, Tao; Jiang, Peipei; Yang, Dingzhong; Hu, Chengzhi; Wu, Bo; Shen, Yonghang

    2013-09-01

    We have experimentally demonstrated a periodically poled magnesium-oxide-doped lithium niobate (PPMgLN)-based, fiber-laser-pumped optical parametric oscillator (OPO) generating idler wavelength of 3.82 μm. The pump fiber laser was constructed with a linearly polarized, semi-fiber-coupled acousto-optic Q-switched fiber oscillator and a polarization-maintaining fiber amplifier with pulse duration of 190 ns at the highest output power. The OPO was specifically configured in single-pass, singly resonant linear cavity structure to avoid the damage risk of the pump fiber laser, which is always a serious issue in the fiber-laser-pumped, double-pass, singly oscillating structured OPOs. Under the highest pump power of 25 W, an idler average output power of 3.27 W with one-hour peak-to-peak instability of 5.2% was obtained. The measured M2 factors were 1.98 and 1.44 for horizontal and vertical axis, respectively. The high power stability and good beam quality demonstrated the suitability of such technology for practical application.

  15. APPLICATIONS OF LASERS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Laser system based on a commercial microwave oscillator with time compression of a microwave pump pulse

    NASA Astrophysics Data System (ADS)

    Arteev, M. S.; Vaulin, V. A.; Slinko, V. N.; Chumerin, P. Yu; Yushkov, Yu G.

    1992-06-01

    An analysis is made of the possibility of using a commercial microsecond microwave oscillator, supplemented by a device for time compression of microwave pulses, in pumping of industrial lasers with a high efficiency of conversion of the pump source energy into laser radiation. The results are reported of preliminary experiments on the commissioning of an excimer XeCl laser.

  16. Demonstration of optical parametric gain generation in the 1 μm regime based on a photonic crystal fiber pumped by a picosecond mode-locked ytterbium-doped fiber laser

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Yang, Si-Gang; Wang, Xiao-Jian; Gou, Dou-Dou; Chen, Hong-Wei; Chen, Ming-Hua; Xie, Shi-Zhong

    2014-01-01

    We report the experimental demonstration of the optical parametric gain generation in the 1 μm regime based on a photonic crystal fiber (PCF) with a zero group velocity dispersion (GVD) wavelength of 1062 nm pumped by a homemade tunable picosecond mode-locked ytterbium-doped fiber laser. A broad parametric gain band is obtained by pumping the PCF in the anomalous GVD regime with a relatively low power. Two separated narrow parametric gain bands are observed by pumping the PCF in the normal GVD regime. The peak of the parametric gain profile can be tuned from 927 to 1038 nm and from 1099 to 1228 nm. This widely tunable parametric gain band can be used for a broad band optical parametric amplifier, large span wavelength conversion or a tunable optical parametric oscillator.

  17. Use of proton pump inhibitors and risk of hip/femur fracture: a population-based case-control study

    PubMed Central

    Pouwels, S.; Lalmohamed, A.; Souverein, P.; Cooper, C.; Veldt, B. J.; Leufkens, H. G.; de Boer, A.; van Staa, T.

    2010-01-01

    Summary Previous studies evaluated the association between proton pump inhibitor (PPI) use and subsequent fracture risk, but they showed ambiguous results. Therefore, the objective was to evaluate this association in a different study population. Our findings show that there is probably no causal relationship between PPI use and hip fracture risk. Introduction Previous studies evaluated the association between PPI use and subsequent fracture risk, but they showed ambiguous results. To further test these conflicting results, the objective of this study was to evaluate the association between the use of PPIs and the risk of hip/femur fracture in a different study population. Methods A case-control study was conducted using data from the Dutch PHARMO record linkage system. The study population included 6,763 cases aged 18 years and older with a first hip/femur fracture during enrolment and 26,341 age-, gender- and region-matched controls. Results Current users of PPIs had an increased risk of hip/femur fracture yielding an adjusted odds ratio (AOR) of 1.20 (95% CI 1.04–1.40). Fracture risk attenuated with increasing durations of use, resulting in AORs of 1.26 (95% CI 0.94–1.68) in the first 3 months, 1.31 (95% CI 0.97–1.75) between 3 and 12 months, 1.18 (95% CI 0.92–1.52) between 13 and 36 months and 1.09 (95% CI 0.81–1.47) for use longer than 36 months. Conclusion Our findings show that there is probably no causal relationship between PPI use and hip fracture risk. The observed association may be the result of unmeasured distortions: although current use of PPIs was associated with a 1.2-fold increased risk of hip/femur fracture, the positive association was attenuated with longer durations of continuous use. Our findings do not support that discontinuation of PPIs decreases risk of hip fracture in elderly patients. PMID:20585937

  18. Pump apparatus including deconsolidator

    DOEpatents

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  19. A Shocking New Pump

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Hydro Dynamics, Inc. received a technical helping hand from NASA that made their Hydrosonic Pump (HPump) a reality. Marshall engineers resolved a bearing problem in the rotor of the pump and recommended new bearings, housings and mounting hardware as a solution. The resulting HPump is able to heat liquids with greater energy efficiency using shock waves to generate heat.

  20. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1994-12-31

    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.

  1. Micromachined peristaltic pumps

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T. (Inventor)

    1999-01-01

    Micromachined pumps including a channel formed between a first membrane and a substrate or between first and second flexible membranes. A series of electrically conductive strips is applied to a surface of the substrate or one of the membranes. Application of a sequential voltage to the series of strips causes a region of closure to progress down the channel to achieve a pumping action.

  2. Solar heat pump

    NASA Astrophysics Data System (ADS)

    Hermanson, R.

    Brief discussions of the major components of a solar powered, chemical ground source heat pump are presented. The components discussed are the solar collectors and the chemical heat storage battery. Sodium sulfide is the medium used for heat storage. Catalog information which provides a description of all of the heat pump systems is included.

  3. Water Treatment Technology - Pumps.

    ERIC Educational Resources Information Center

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on pumps provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pumps in plant and distribution systems, pump…

  4. NEUTRONIC REACTOR FUEL PUMP

    DOEpatents

    Cobb, W.G.

    1959-06-01

    A reactor fuel pump is described which offers long life, low susceptibility to radiation damage, and gaseous fission product removal. An inert-gas lubricated bearing supports a journal on one end of the drive shsft. The other end has an impeller and expansion chamber which effect pumping and gas- liquid separation. (T.R.H.)

  5. Advances in pump technology: insulin patch pumps, combined pumps and glucose sensors, and implanted pumps.

    PubMed

    Schaepelynck, P; Darmon, P; Molines, L; Jannot-Lamotte, M F; Treglia, C; Raccah, D

    2011-12-01

    This review discusses the most recent developments in insulin pump technology. The benefits of the insulin pump to patients with type 1 diabetes are recognized both for its metabolic effectiveness and its positive effects on quality of life. The current pumps are reliable, small and light, and are becoming more and more sophisticated. Nevertheless, there remain practical and psychological constraints for the patient. However, recent patch-pump advances should simplify the technical aspects of pump treatment and enhance patient comfort. Another advance combines the insulin pump with a glucose sensor. Such a combination is logical for optimizing pump use and, to that end, developing an automated or 'closed-loop'system that permits the delivery of subcutaneous insulin adjusted according to measured levels of subcutaneous glucose. Finally, implanted insulin pumps have proven their worth not only because of their simple use, but also for their contribution in the artificial pancreas project. Indeed, the prompt response with intraperitoneal administration of insulin makes it of interest for use in a closed-loop system.

  6. Classification of physiologically significant pumping states in an implantable rotary blood pump: patient trial results.

    PubMed

    Karantonis, Dean M; Mason, David G; Salamonsen, Robert F; Ayre, Peter J; Cloherty, Shaun L; Lovell, Nigel H

    2007-01-01

    An integral component in the development of a control strategy for implantable rotary blood pumps is the task of reliably detecting the occurrence of left ventricular collapse due to overpumping of the native heart. Using the noninvasive pump feedback signal of impeller speed, an approach to distinguish between overpumping (or ventricular collapse) and the normal pumping state has been developed. Noninvasive pump signals from 10 human pump recipients were collected, and the pumping state was categorized as either normal or suction, based on expert opinion aided by transesophageal echocardiographic images. A number of indices derived from the pump speed waveform were incorporated into a classification and regression tree model, which acted as the pumping state classifier. When validating the model on 12,990 segments of unseen data, this methodology yielded a peak sensitivity/specificity for detecting suction of 99.11%/98.76%. After performing a 10-fold cross-validation on all of the available data, a minimum estimated error of 0.53% was achieved. The results presented suggest that techniques for pumping state detection, previously investigated in preliminary in vivo studies, are applicable and sufficient for use in the clinical environment.

  7. Dielectric elastomer pump for artificial organisms

    NASA Astrophysics Data System (ADS)

    Bowers, Amy E.; Rossiter, Jonathan M.; Walters, Peter J.; Ieropoulos, Ioannis A.

    2011-04-01

    This paper presents a bio-inspired, dielectric elastomer (DE) based tubular pumping unit, developed for eventual use as a component of an artificial digestive tract onboard a microbial fuel cell powered robot (EcoBot). The pump effects fluid displacement by direct actuation of the tube wall as opposed to excitation by an external body. The actuator consists of a DE tube moulded from silicone, held in a negative pressure chamber, which is used for prestraining the tube. The pump is coupled with custom designed polymeric check valves in order to rectify the fluid flow and assess the performance of the unit. The valves exhibited the necessary low opening pressures required for use with the actuator. The tube's actuation characteristics were measured both with and without liquid in the system. Based on these data the optimal operating conditions for the pump are discussed. The pump and valve system has achieved flowrates in excess of 40μl/s. This radially contracting/expanding actuator element is the fundamental component of a peristaltic pump. This 'soft pump' concept is suitable for biomimetic robotic systems, or for the medical or food industries where hard contact with the delivered substrate may be undesirable. Future work will look at connecting multiple tubes in series in order to achieve peristalsis.

  8. Deep well solar pump

    SciTech Connect

    Vanek, J.

    1990-02-06

    This patent describes, in a pump having a source of gas under pressure, and a gas operated pump, a mechanism periodically injecting gas from the source of gas into the gas operated pump. It comprises: a long period pendulum turning towards a first position by gravity, an injection valve connected between the source of gas under pressure and the gas operated pump, a linkage between the pendulum and the injection valve. The linkage opening the injection valve when the pendulum is in the first position, an impulse tube connected between the injection valve and the gas operated pump, a member having a surface adjacent to the first position of the pendulum, and an elastic impulse bladder connected to the impulse tube adjacent to the surface so that inflation of the impulse bladder on the opening of the injection valve forces the impulse bladder against the pendulum urging the pendulum against the force of gravity toward a second position.

  9. Centrifugal pump fuel system

    SciTech Connect

    McGlone, M.E.; Larkins, L.J.; Johnson, R.O.; Moeller, K.A.

    1993-06-22

    A centrifugal pump fuel system for an engine driven fuel pump for an aircraft gas turbine engine is described comprising: a centrifugal pump having at constant speed rising head/flow characteristic at low flows; a plumbing system receiving flow from the pump, and having at least one control valve located down stream of and defining a discrete volume of the plumbing system; a plumbing resonant frequency defined by the discrete volume, the geometry of the plumbing system, and the bulk modulus of the fuel; a pressure difference regulating valve located adjacent to the discharge of the pump, up stream of the vast majority of the discrete volume; and the frequency response of the regulating valve being significantly less than the frequency response of the plumbing system such that the response of the regulating valve is attenuated at the resonant frequency of the plumbing system.

  10. Rotary Blood Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1996-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  11. A Valveless Pump

    NASA Astrophysics Data System (ADS)

    Bringley, Thomas; Childress, Stephen; Vandenberghe, Nicolas

    2004-11-01

    We study experimentally a simple valveless mechanical pump. The pumping mechanism could help to explain the successful circulation of blood in the cardiovascular systems of the human fetus, certain organisms whose hearts have no valves, and a person undergoing CPR. Because of its simplicity, the pump may also have applications in microfluidics. The experimental setup consists of two connected sections of tube, one rigid and one elastic, filled with water. To pump, a segment of the elastic section is pressed closed periodically. We examine the effects of varying the location of the forced segment and the forcing frequency. Both the magnitude and the direction of the pumping are observed to depend on both parameters. Moreover, certain frequencies result in destructive interference or resonance. We present some simple numerical models to try to explain these observations.

  12. High pressure liquid gas pump

    NASA Technical Reports Server (NTRS)

    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.

  13. Oxygenation to Bovine Blood in Artificial Heart and Lung Using Vibrating Flow Pump: Experiment and Numerical Analysis Based on Non-Newtonian Model

    NASA Astrophysics Data System (ADS)

    Shintaku, Hirofumi; Yonemura, Tsubasa; Tsuru, Kazuaki; Isoyama, Takashi; Yambe, Tomoyuki; Kawano, Satoyuki

    In this study, we construct an experimental apparatus for a prototype artificial heart and lung (AHL) by installing hollow fibers into the cylindrical tube of the vibrating flow pump (VFP). The oxygenation characteristics are investigated both by experiments using bovine blood and by numerical analyses based on the computational fluid dynamics. The analyses are carried out at the Reynolds numbers Re ranged from O(1) to O(103), which are determined based on the experimental conditions. The blood flow and the diffusion of oxygen gas are analyzed based on the Newtonian/non-Newtonian, unsteady, incompressible and axisymmetric Navier-Stokes equations, and the advection-diffusion equation. The results show that the oxygenation rate increases in proportion to Re1/3, where the phenomenon corresponds to the decreasing thickness of the concentration boundary layer with Re. Although the effects of the vibrating flow and the rheology of the blood are clearly appeared on the velocity field, their effects on the gas exchange are relatively small at the ranges of prescribed Reynolds numbers. Furthermore, the numerical results in terms of the oxygenation rate are compared with the experimental ones. The basic design data of VFP were accumulated for the development of AHL in the clinical applications.

  14. Solar-pumped solid-state lasers

    SciTech Connect

    Weksler, M.; Shwartz, J.

    1988-06-01

    Results are presented for direct solar pumping of a ND:YAG rod laser. Stable CW output of more than 60 W was obtained with a slope efficiency exceeding 2 percent. A compound parabolic concentrator, designed to increase the solar radiation coupled into the laser rod, was used in these experiments. The results are consistent with predictions based on a simple solar-pumped laser model, which is also presented. Using this model, it is shown that existing laser materials with broad-band absorption characteristics (e.g., alexandrite and Nd:Cr:GSGG) have a potential for better than 10 percent overall conversion efficiency when solar pumped.

  15. Custom Unit Pump Development for the EVA PLSS

    NASA Technical Reports Server (NTRS)

    Schuller, Michael; Kurwitz, Cable; Little, Frank; Oinuma, Ryoji; Larsen, Ben; Goldman, Jeff; Reinis, Filip; Trevino, Luis

    2010-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design and test a pre-flight prototype pump for use in the Extra-vehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump must accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting non-condensable gas without becoming air locked. The chosen pump design consists of a 28 V DC, brushless, seal-less, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES verified that the pump meets the design requirements for range of flow rates, pressure drop, power consumption, working fluid temperature, operating time, gas ingestion, and restart capability under both ambient and vacuum conditions. The pump operated at 40 to 240 lbm/hr flow rate, 35 to 100 oF pump temperature, and 5 to 10 psid pressure rise. Power consumption of the pump controller at the nominal operating point in both ambient and vacuum conditions was 9.5 W, which was less than the 12 W predicted. Gas ingestion capabilities were tested by injecting 100 cc of air into the fluid line; the pump operated normally throughout this test.

  16. Modular pump head design of diffused, metal, and hybrid pump geometry for diode-side-pumped high power Nd:YAG laser.

    PubMed

    Sundar, R; Ranganathan, K; Hedaoo, P; Bindra, K S

    2016-09-20

    In this paper, we present a comparative study on pump heads for a high power diode-side-pumped Nd:YAG laser. The pump head is a modular type, which is in the form of discs, with each disc holding three pump diodes kept at 120° with respect to each other. Unabsorbed pump light from the active medium is reflected by reflectors mounted adjacent to the pump diodes. The performance of a high power pump head made of modular discs mounted with specular or diffused type reflectors was studied. Hybrid pump geometry was also investigated, where the pump head is made up of discs loaded with metal and diffused reflectors, alternately. The discs are loaded around the active medium in such a way that successive discs are rotated by sixty degrees with respect to each other. Fluorescence profiles, thermal lensing, laser output power, and M2 values were studied for pump heads made up of metal, diffused, and hybrid type reflectors. All of the pump heads were studied for three different resonator lengths to maximize the output power with the best beam quality. The experimental results show that the diffused reflector-based geometry in a sixty degree rotated configuration produced the maximum output power and best beam quality in terms of the M2 value.

  17. General-purpose infusion pumps.

    PubMed

    1998-01-01

    General-purpose infusion pumps deliver liquid medications to patients through intravenous or epidural routes at specified flows. They are most often used in hospitals and alternative care settings (e.g., physician' offices, patients' homes) when liquid medications need to be administered with greater accuracy or at higher flows than can be provided through a manually adjusted gravity administration set. In this Update of our February 1997 Evaluation of infusion pumps (Health Devices 26[2]), we tested 3 additional pumps from 3 suppliers. We also rated and ranked them in comparison with the 16 units from the February 1997 study that are still being produced. With a few exceptions, we tested the new pumps against the same criteria and using the same test methods as those in the previous Evaluation. However, for this Update, the focus of our findings has broadened: although we continue to place strong emphasis on the pumps' protection against gravity free-flow, we also give significant weight to their overall safety, performance, and human factors design. As a result, our ratings and rankings scheme has changed, affecting the rankings of some of the previously evaluated units. Of the 19 currently available units that have been evaluated to date, we rated 13 units Acceptable, with 5 of those units ranked above the other 8. A further 5 units were rated Conditionally Acceptable; we consider them Acceptable if they are used with the available free-flow protection. And 1 unit had performance problems that caused us to rate it Unacceptable (this unit has been recalled by its supplier; see the inset on page 162). As always, we caution readers not to base selection and purchasing decisions on our conclusions alone, but on a thorough understanding of the issues behind those conclusions, which can be gained by reading this Evaluation in its entirety and carefully reviewing the February 1997 issue.

  18. Apparatus for Pumping a Fluid

    NASA Technical Reports Server (NTRS)

    Boeyen, Robert Van; Reeh, Jonathan

    2013-01-01

    A fluid pump has been developed for mechanically pumped fluid loops for spacecraft thermal control. Lynntech's technology utilizes a proprietary electrochemically driven pumping mechanism. Conventional rotodynamic and displacement pumps typically do not meet the stringent power and operational reliability requirements of space applications. Lynntech's developmental pump is a highly efficient solid-state pump with essentially no rotating or moving components (apart from metal bellows).

  19. Interchangeability of gas detection tubes and hand pumps.

    PubMed

    Haag, W R

    2001-01-01

    Users of gas detection tubes occasionally seek the convenience of using a single hand pump with different brands of tubes, to avoid the need to carry more than one pump. Several professional organizations recommend against such interchange. However, these recommendations appear to be based on a single study of pump designs that mostly are no longer in use. The present study was undertaken to determine if current hand pumps are interchangeable. Both piston-type and bellows-type hand pumps were evaluated by comparing pump flow profiles and test gas measurements with a variety of tubes. The results demonstrate that three piston hand pumps in common use (Sensidyne/Gastec GV/100, RAE Systems LP-1200, and Matheson-Kitagawa 8104-400A) are fully interchangeable. Two bellows pumps (Draeger Accuro and MSA Kwik-Draw) also are interchangeable with each other. Mixing of bellows and piston systems is often possible, but there are enough exceptions to conclude that such practice should be discouraged because it can give inaccurate readings. It is recommended that technical standards be adopted, such as total volume and an initial pump vacuum or a pump flow curve, to assess hand pump interchangeability. When two manufacturers' pumps meet the same standard and routine leak tests are conducted, interchangeability is scientifically valid and poses no risk to the end user while offering greater convenience.

  20. Control of natural circulation loops by electrohydrodynamic pumping

    NASA Astrophysics Data System (ADS)

    Grassi, W.; Testi, D.; Della Vista, D.

    2014-04-01

    The paper analyses the effect of electrohydrodynamic (EHD) pumping on the control of natural circulation loops (NCLs). The two major objectives of the investigation are: finding the optimal configuration of an EHD pump and demonstrating that the NCL flow direction can be inverted by exploiting the EHD phenomena. In the initial experimental set-up, we measured the static pressure rise given by an EHD pump made of three consecutive modules of point-ring electrodes for different dielectric fluids and electrode materials. When reversing the polarity of the applied DC voltage, we observed opposite pumping directions, suggesting the presence of two distinct EHD phenomena, inducing motion on opposite directions: ion-drag pumping and conduction pumping. The former was identified as a more efficient process compared to the latter. Based on these preliminary experiments, we built a NCL, operating with the fluid HFE-7100. Two oppositely mounted optimised pumping sections could be alternately activated, to promote clockwise or anticlockwise motion. In the first series of tests, alternately, the pumping sections were triggered prior to the heat input. In any case, the circulation followed the EHD pumping direction. In other tests, the electric field was applied when natural circulation was already present and the flow was reversed by means of opposite EHD pumping, at both polarities. Simply inverting the polarity of the applied voltage, we could alternate ion-drag and conduction pumping; in this way, we easily controlled the direction of motion by means of a single EHD pumping device.

  1. Diamagnetic pumping in a rotating convection zone

    NASA Astrophysics Data System (ADS)

    Kitchatinov, L. L.; Nepomnyashchikh, A. A.

    2016-10-01

    Solar dynamo models require some mechanism for magnetic field concentration near the base of the convection zone in order to generate super-kilogauss toroidal fields with sufficiently large (∼ 1024 Mx) magnetic flux. We consider the downward diamagnetic pumping near the base of the convection zone as a possible concentration mechanism and derive the pumping velocities with allowance for the effect of rotation. Transport velocities for poloidal and toroidal fields differ in rotating fluid. The toroidal field is transported downward along the radius only but the pumping velocity for the poloidal field has an equatorward meridional component also. Previous results for cases of slow and rapid rotation are reproduced and the diamagnetic pumping expressions adapted for use in dynamo models are presented.

  2. Pressure charged airlift pump

    DOEpatents

    Campbell, Gene K.

    1983-01-01

    A pumping system is described for pumping fluids, such as water with entrained mud and small rocks, out of underground cavities such as drilled wells, which can effectively remove fluids down to a level very close to the bottom of the cavity and which can operate solely by compressed air pumped down through the cavity. The system utilizes a subassembly having a pair of parallel conduit sections (44, 46) adapted to be connected onto the bottom of a drill string utilized for drilling the cavity, the drill string also having a pair of coaxially extending conduits. The subassembly includes an upper portion which has means for connection onto the drill string and terminates the first conduit of the drill string in a plenum (55). A compressed air-driven pump (62) is suspended from the upper portion. The pump sucks fluids from the bottom of the cavity and discharges them into the second conduit. Compressed air pumped down through the first conduit (46) to the plenum powers the compressed air-driven pump and aerates the fluid in the second conduit to lift it to the earth's surface.

  3. Deep well pump

    SciTech Connect

    Downen, J.L.; Sutliff, W.N.

    1981-06-16

    A pump barrel open at its lower end is coupled at its upper end by a tubular adapter assembly to the lower end of a pump tubing string. This assembly presents an internal bevelled sealing latching annulus, an axially bored pump head being radially expansively spring latched in a fixed axial sealed relation with the annulus to seal the upper end of the pump barrel from the adapter assembly to form a pump compression chamber surrounding a hollow polish rod extending upwardly from a plunger mounted on the lower end of the polish rod for reciprocation in the pump barrel. The plunger carries tandem travelling valves close beneath its connection with the polish rod. The lower valve opening to receive oil through the barrel and plunger on the down stroke and concurrently delivering such oil into the compression chamber. The upper valve closes on the down stroke and opening on the up stroke during which the lower valve closes to expel oil trapped in the compression chamber upward through the upper valve into the lower end of the hollow polish rod which oil is discharged at the upper end thereof into the pump tubing string through the fitting adapting the polish rod to the lower end of the sucker rod.

  4. Fuel injection pump

    SciTech Connect

    Iiyama, A.; Nishimura, T.

    1988-12-06

    This patent describes a fuel injection pump comprising: (a) engageable first and second cam members, the first cam member reciprocating axially as the first cam member moves angularly relative to the second cam member when the first and second cam members are in engagement; (b) means for urging the first cam member toward the second cam member to engage the first and second cam members; (c) a plunger connected to the first cam member for reciprocation with the first cam member, the plunger defining at least a part of a pumping chamber, the pumping chamber contracting and expanding as the plunger reciprocates; (d) means for allowing fuel to move into the pumping chamber as the pumping chamber expands in a fuel intake stroke; (e) means for allowing the fuel to move out of the pumping chamber as the pumping chamber contracts in a fuel compression stroke; and (f) means for resisting movement of the plunger in at least part of the fuel compression stroke and relieving resistance to the movement of the plunger in the fuel intake stroke wherein the resisting means comprises a piston slidably mounted on the plunger, a spring urging the piston to seat the piston on a shoulder on the plunger so that the piston reciprocates as the plunger reciprocates, wherein the piston is seated on the shoulder in the fuel compression stroke and separates from the shoulder against the force of the spring in the fuel intake stroke, a second fluid chamber at least partially defined by the piston.

  5. Variable displacement vane pump

    SciTech Connect

    Tschantz, J.S.; Bisson, B.J.

    1997-12-31

    What has been developed under this program is a pumping system which can vary the amount of fuel delivered according to engine needs, thereby reducing the temperature rise of the fuel to very low levels. This permits the elimination of the air/oil coolers and conserves the vital airflow through the fan. The variable displacement vane pump (VDVP) also permits a substantial simplification of the control system with the elimination of complex metering valves, offering a significant reduction in fuel system cost. This program was initiated to develop a technology that embodied the ruggedness of the gear pump with the efficiency and metering versatility of the variable displacement vane pump. Thick metal vanes emulate the teeth on pumping gears while the simple, elegant swing cam feature provides the variable displacement capability without the unwieldy multiple cam segments found in other concepts. The result is a pumping architecture which is rugged, light in weight and extremely versatile, having demonstrated superb heat management and controllability in extensive bench and engine testing. This paper will report the results that the pumps have achieved to date both in terms of durability and efficiency.

  6. Multiphase pumping - operation & control

    SciTech Connect

    Salis, J. de; Marolies, C. de; Falcimaigne, J.

    1996-12-31

    This paper reviews field issues related to the planning, installation and operation of the helico-axial multiphase pumps. Interest for multiphase production, which leads to simpler and smaller in-field installations, is primarily dictated by the need for more a cost effective production system. Multiphase pumping is essentially a means of adding energy to the unprocessed effluent which enables the liquid/gas mixture to be transported over long distances without the need for prior separation. The Poseidon helico-axial pumps, under normal operating conditions, are largely unaffected by process fluctuations at pump inlet (changes in pressure, liquid or gas flow rate). They have demonstrated a stable behavior (self-adaptive capability with regards to instantaneous changes). A multiphase pump set is designed to operate under changing/fluctuating process conditions. An important issue related to pump operability and flexibility has to do with the driver selection: fixed speed vs. variable speed. In some cases a fixed speed drive provides sufficient operational flexibility. In other cases variable speed can be chosen. Pump operation & control strategies are presented and discussed.

  7. Microfluidic reflow pumps.

    PubMed

    Haslam, Bryan; Tsai, Long-Fang; Anderson, Ryan R; Kim, Seunghyun; Hu, Weisheng; Nordin, Gregory P

    2015-07-01

    A new microfluidic pump, termed a reflow pump, is designed to operate with a sub-μl sample volume and transport it back and forth between two pneumatically actuated reservoirs through a flow channel typically containing one or more sensor surfaces. The ultimate motivation is to efficiently use the small sample volume in conjunction with convection to maximize analyte flux to the sensor surface(s) in order to minimize sensor response time. In this paper, we focus on the operational properties of the pumps themselves (rather than the sensor surfaces), and demonstrate both two-layer and three-layer polydimethylsiloxane reflow pumps. For the three-layer pump, we examine the effects of reservoir actuation pressure and actuation period, and demonstrate average volumetric flow rates as high as 500 μl/min. We also show that the two-layer design can pump up to 93% of the sample volume during each half period and demonstrate integration of a reflow pump with a single-chip microcantilever array to measure maximum flow rate.

  8. Advanced heat pump research and development

    NASA Astrophysics Data System (ADS)

    Kuliasha, M. A.

    The Office of Building Energy Research and Development of the U.S. Department of Energy (DOE), has been funding R&D in advanced heat pumps and appliances since 1976. Much of that research has been managed for DOE by the Oak Ridge National Laboratory (ORNL). The objective of the Building Equipment Research (BER) program at ORNL has been to generate new concepts and develop a technology base for improving the energy efficiency and load characteristics of energy conversion equipment used in residential and commercial buildings. The research being pursued to achieve these objectives falls under three general areas: thermally activated heat pumps (TAHP), refrigeration systems, and building equipment systems. The TAHP work is concentrated on three technologies: (1) absorption heat pumps; (2) Stirling engine-driven heat pumps; and (3) internal combustion (IC) engine-driven heat pumps. Major project areas in refrigeration systems research include electric heat pumps, ground-coupled heat pumps, and refigerant mixtures. In the building equipment systems areas, project areas include advanced distribution systems, advanced insulation for appliances, and commercial building equipment.

  9. spin pumping occurred under nonlinear spin precession

    NASA Astrophysics Data System (ADS)

    Zhou, Hengan; Fan, Xiaolong; Ma, Li; Zhou, Shiming; Xue, Desheng

    Spin pumping occurs when a pure-spin current is injected into a normal metal thin layer by an adjacent ferromagnetic metal layer undergoing ferromagnetic resonance, which can be understood as the inverse effect of spin torque, and gives access to the physics of magnetization dynamics and damping. An interesting question is that whether spin pumping occurring under nonlinear spin dynamics would differ from linear case. It is known that nonlinear spin dynamics differ distinctly from linear response, a variety of amplitude dependent nonlinear effect would present. It has been found that for spin precession angle above a few degrees, nonlinear damping term would present and dominated the dynamic energy/spin-moment dissipation. Since spin pumping are closely related to the damping process, it is interesting to ask whether the nonlinear damping term could be involved in spin pumping process. We studied the spin pumping effect occurring under nonlinear spin precession. A device which is a Pt/YIG microstrip coupled with coplanar waveguide was used. High power excitation resulted in spin precession entering in a nonlinear regime. Foldover resonance lineshape and nonlinear damping have been observed. Based on those nonlinear effects, we determined the values of the precession cone angles, and the maximum cone angle can reach a values as high as 21.5 degrees. We found that even in nonlinear regime, spin pumping is still linear, which means the nonlinear damping and foldover would not affect spin pumping process.

  10. Design of a Bearingless Blood Pump

    NASA Technical Reports Server (NTRS)

    Barletta, Natale; Schoeb, Reto

    1996-01-01

    In the field of open heart surgery, centrifugal blood pumps have major advantages over roller pumps. The main drawbacks to centrifugal pumps are however problems with the bearings and with the sealing of the rotor shaft. In this paper we present a concept for a simple, compact and cost effective solution for a blood pump with a totally magnetically suspended impeller. It is based on the new technology of the 'Bearingless Motor' and is therefore called the 'Bearingless Blood Pump.' A single bearingless slice motor is at the same time a motor and a bearing system and is able to stabilize the six degrees of freedom of the pump impeller in a very simple way. Three degrees of freedom are stabilized actively (the rotation and the radial displacement of the motor slice). The axial and the angular displacement are stabilized passively. The pump itself (without the motor-stator and the control electronics) is built very simply. It consists of two parts only: the impeller with the integrated machine rotor and the housing. So the part which gets in contact with blood and has therefore to be disposable, is cheap. Fabricated in quantities, it will cost less than $10 and will therefore be affordable for the use in a heart-lung-machine.

  11. Pump-turbines. January, 1974-July, 1981 (citations from the BHRA Fluid Engineering Data Base). Report for Jan 74-Jul 81

    SciTech Connect

    Not Available

    1981-08-01

    This bibliography cites reports on pump turbines pertaining to pumped storage, but includes a few references to other applications. The citations cover design, development, testing, operational evaluation and problem areas. Many of the citations reference reports on flow characteristics, including draft tube surges, dynamic loads and forces, vibration, cavitation, and starting problems. Citations cover both the pumping mode and the turbine (generating) mode, for analyses of speed rise, overpressure, overspeed, and general flow investigations. (Contains 178 citations fully indexed and including a title list.)

  12. Variable-Rate Pumping Test Analysis for Aquifer Parameter Evaluation

    NASA Astrophysics Data System (ADS)

    Birdsell, K. H.; Mishra, P. K.

    2011-12-01

    The most common method to infer aquifer properties is based on analysis of drawdown and/or recovery data recorded from pumping tests. The analysis is frequently based on fitting observed pressure responses to appropriate analytical solutions for radial flow towards the pumping well. For mathematical simplicity, analytical solutions are commonly derived for constant-rate pumping conditions. However, often times the pumping rate during the test is varied either intentionally or due to technical difficulties during the test. Using principles of superposition, the constant-rate analytical solutions are frequently applied to analyze pumping tests that are conducted with variable pumping rates. In this study, we propose a novel methodology that approximates a time-varying pumping history as a series of segments with linearly varying pumping rates, and use it to evaluate the effects of pumping variation on aquifer parameter estimation. Our approach is demonstrated using existing analytical solutions for confined aquifers (Mishra and Neuman 2011), but it is also applicable to unconfined and/or leaky aquifers. The methodology is validated using a synthetic pumping test. We also apply our methodology to analyze the pumping test data by inversely estimating the apparent aquifer parameters using the code MADS (http://ees.lanl.gov/staff/monty/codes/mads).

  13. Incoherently pumped continuous wave dye laser

    NASA Astrophysics Data System (ADS)

    Thiel, E.; Zander, C.; Drexhage, K. H.

    1987-05-01

    Continuous wave operation of a dye laser, pumped by an incoherent light source, is reported. A jet of a water-based solution of Rhodamine 6G is used as the laser medium in a spherical cavity with high reflectivity mirrors. Two high pressure arcs generated by electrical discharge between tungsten electrodes serve as pump source. They produce a power density of 0.5-10 kW/cm 2 in the jet causing the dye to lase at 615 nm.

  14. A finite-element-based perturbation model for the rotordynamic analysis of shrouded pump impellers: Part 1: Model development and applications

    NASA Technical Reports Server (NTRS)

    Baskharone, Erian A.

    1993-01-01

    This study concerns the rotor dynamic characteristics of fluid-encompassed rotors, with special emphasis on shrouded pump impellers. The core of the study is a versatile and categorically new finite-element-based perturbation model, which is based on a rigorous flow analysis and what we have generically termed the 'virtually' deformable finite-element approach. The model is first applied to the case of a smooth annular seal for verification purposes. The rotor excitation components, in this sample problem, give rise to a purely cylindrical, purely conical, and a simultaneous cylindrical/conical rotor whirl around the housing centerline. In all cases, the computed results are compared to existing experimental and analytical data involving the same seal geometry and operating conditions. Next, two labyrinth-seal configurations, which share the same tooth-to-tooth chamber geometry but differ in the total number of chambers, were investigated. The results, in this case, are compared to experimental measurements for both seal configurations. The focus is finally shifted to the shrouded-impeller problem, where the stability effects of the leakage flow in the shroud-to-housing secondary passage are investigated. To this end, the computational model is applied to a typical shrouded-impeller pump stage, fabricated and rotor dynamically tested by Sulzer Bros., and the results compared to those of a simplified 'bulk-flow' analysis and Sulzer Bros.' test data. In addition to assessing the computed rotor dynamic coefficients, the shrouded-impeller study also covers a controversial topic, namely that of the leakage-passage inlet swirl, which was previously cited as the origin of highly unconventional (resonance-like) trends of the fluid-exerted forces. In order to validate this claim, a 'microscopic' study of the fluid/shroud interaction mechanism is conducted, with the focus being on the structure of the perturbed flow field associated with the impeller whirl. The conclusions

  15. Mid-infrared rotated image singly resonant twisted rectangle optical parametric oscillator based on HgGa(2)S(4) pumped at 1064 nm.

    PubMed

    Marchev, Georgi; Reza, Manuel; Badikov, Valeriy; Esteban-Martin, Adolfo; Stöppler, Georg; Starikova, Marina; Badikov, Dmitrii; Panyutin, Vladimir; Eichhorn, Marc; Shevyrdyaeva, Galina; Tyazhev, Aleksey; Sheina, Svetlana; Agnesi, Antonio; Fintisova, Anna; Petrov, Valentin

    2014-11-20

    We compare linear, planar ring, and rotated image singly resonant twisted rectangle (RISTRA) type nanosecond optical parametric oscillator cavities using HgGa2S4 nonlinear crystal pumped by 8 ns pulses at 1064 nm from a low beam quality pump source. The input-output characteristics and the output idler beam quality at 6300 nm are compared for two values of the pump beam diameter presenting different cavity Fresnel numbers and magnitudes of the spatial walk-off effect due to birefringence. The RISTRA cavity ensures in all cases a circular output beam profile but is advantageous in terms of beam quality with respect to the planar ring only at a large pump beam diameter.

  16. The Safety of Appropriate Use of Over-the-Counter Proton Pump Inhibitors: An Evidence-Based Review and Delphi Consensus.

    PubMed

    Johnson, David A; Katz, Philip O; Armstrong, David; Cohen, Henry; Delaney, Brendan C; Howden, Colin W; Katelaris, Peter; Tutuian, Radu I; Castell, Donald O

    2017-04-01

    The availability of over-the-counter (OTC) proton pump inhibitors (PPIs) for the short-term (2 weeks) management of frequent heartburn (≥2 days/week) has increased markedly, yet evidence-based recommendations have not been developed. A panel of nine international experts in gastroesophageal reflux disease developed consensus statements regarding the risks and benefits of OTC PPIs using a modified Delphi process. Consensus (based on ≥80% approval) was reached through multiple rounds of remote voting and a final round of live voting. To identify relevant data, the available literature was searched and summarized. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system terminology was used to rate the quality of evidence and strength of recommendations; consensus was based on ≥2/3 agreement. After 4 rounds of review, consensus was achieved for 18 statements. Notably, the available data did not directly reflect OTC use, but instead, prescription use; therefore, extrapolations to the OTC setting were often necessary. This limitation is regrettable, but it justifies performing this exercise to provide evidence-based expert opinion on a widely used class of drugs. The panel determined that using OTC PPIs according to label instructions is unlikely to mask the symptoms of esophageal or gastric cancer or adversely impact the natural history of related precursor conditions. OTC PPIs are not expected to substantially affect micronutrient absorption or bone mineral density or cause community-acquired pneumonia, Clostridium difficile infection, or cardiovascular adverse events. However, OTC PPI use may be associated with slightly increased risks for infectious diarrhea, certain idiosyncratic reactions, and cirrhosis-related spontaneous bacterial peritonitis. The available evidence does not suggest that OTC PPI use consistent with label instructions is associated with substantial health risks. To minimize potential risks, healthcare

  17. [The use experience of enteral nutrition pump (Applix Smart)].

    PubMed

    Kobayashi, Kaoru; Shirai, Atsushi; Uryu, Shinichi; Kikuchi, Shiro; Momozono, Shinobu; Shimizu, Haruyuki

    2006-12-01

    Nutritional management by using enteral feeding method of nutrition is required for patients of gastroenterological disease with functional disorder in digestion-absorption, and for cases where the patients have difficulty in taking food orally. There are many cases where enteral nutrition pumps are used for administration of nutritious medicines. Approximately 150 enteral nutrition pumps (including house use and home rental) have currently been utilized at our facility. The department of ME Center takes care of enteral nutrition pumps for maintenance and control. On the other hand, we needed to conduct a study for a new pump in replacing Frenta System IV due to the pump was no longer available. At this presentation, we are introducing a new pump manufactured by Fresenius as a replacement of the Frenta System IV. In the meantime, we would like to report a comparison examination of the pump based on its functionality, performance and user friendliness from the view from a clinical technologist as well.

  18. Targeting efflux pumps to overcome antifungal drug resistance.

    PubMed

    Holmes, Ann R; Cardno, Tony S; Strouse, J Jacob; Ivnitski-Steele, Irena; Keniya, Mikhail V; Lackovic, Kurt; Monk, Brian C; Sklar, Larry A; Cannon, Richard D

    2016-08-01

    Resistance to antifungal drugs is an increasingly significant clinical problem. The most common antifungal resistance encountered is efflux pump-mediated resistance of Candida species to azole drugs. One approach to overcome this resistance is to inhibit the pumps and chemosensitize resistant strains to azole drugs. Drug discovery targeting fungal efflux pumps could thus result in the development of azole-enhancing combination therapy. Heterologous expression of fungal efflux pumps in Saccharomyces cerevisiae provides a versatile system for screening for pump inhibitors. Fungal efflux pumps transport a range of xenobiotics including fluorescent compounds. This enables the use of fluorescence-based detection, as well as growth inhibition assays, in screens to discover compounds targeting efflux-mediated antifungal drug resistance. A variety of medium- and high-throughput screens have been used to identify a number of chemical entities that inhibit fungal efflux pumps.

  19. Optimal heat pumps for solar-assisted heat-pump systems

    NASA Astrophysics Data System (ADS)

    Catan, M. A.

    Work at Brookhaven National Laboratory (BNL) investigates the design of optimal heat pumps for solar assisted heat pump (SAPH) systems. Heat pump designs suitable for two generic systems, identified in the course of recent analytical work, are being studied. These are series SAHP systems operating at evaporator temperatures in the -5 to 10 C range and those operating at evaporator temperatures in the 10 to 35 C range. A heat pump simulator has been constructed with liquid based source subsystem and two load subsystems, one for testing air cooled condensers and one for testing water cooled condensers. Heat pumps tested were composed of various components including several types of variable and fixed capacity compressors, two types of expansion devices, and heat exchangers varying in size and type.

  20. Liquid Metal Pump Technologies for Nuclear Surface Power

    NASA Technical Reports Server (NTRS)

    Polzin, Kurt A.

    2007-01-01

    Multiple liquid metal pump options are reviewed for the purpose of determining the technologies that are best suited for inclusion in a nuclear reactor thermal simulator intended to test prototypical space nuclear system components. Conduction, induction, and thermoelectric electromagnetic pumps are evaluated based on their performance characteristics and the technical issues associated incorporation into a reactor system. The thermoelectric electromagnetic pump is recommended for inclusion in the present system based on favorable quantitative and qualitative measures relative to the other options under consideration.

  1. Absorption heat pump system

    DOEpatents

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  2. Intelligent pumping system developed

    SciTech Connect

    Not Available

    1983-06-01

    The oil field's first intelligent rod pumping system designed specifically to reduce the cost of pumping oil wells now is a reality. As a plus benefit, the system (called Liftronic) is compact and quiet. The new system combines an efficient mechanical design with a computer control system to reduce pumping costs. The unit stands less than 8 ft high, or approx. one-fourth the height of a comparable beam unit. It also mounts directly on the wellhead. The entire system can be concealed behind a fence or enclosed within a small building to make it a more attractive neighbor in residential, commercial, or recreational areas. It is useful also for agricultural areas where overhead irrigation systems restrict the use of many oil field pumping systems.

  3. Keeping Hearts Pumping

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A collaboration between NASA, Dr. Michael DeBakey, Dr. George Noon, and MicroMed Technology, Inc., resulted in a life-saving heart pump for patients awaiting heart transplants. The MicroMed DeBakey VAD functions as a "bridge to heart transplant" by pumping blood throughout the body to keep critically ill patients alive until a donor heart is available. Weighing less than 4 ounces and measuring 1 inch by 3 inches, the pump is approximately one-tenth the size of other currently marketed pulsatile VADs. This makes it less invasive and ideal for smaller adults and children. Because of the pump's small size, less than 5 percent of the patients implanted developed device-related infections. It can operate up to 8 hours on batteries, giving patients the mobility to do normal, everyday activities.The MicroMed DeBakey VAD is a registered trademark of MicroMed Technology, Inc.

  4. Regenerative Hydride Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  5. Selecting multiphase pumps

    SciTech Connect

    Prang, A.J.

    1997-02-01

    Multiphase pumps in petroleum applications today must handle liquid products containing large amounts of gas, and often including water and sand as well. In the past, gas was commonly separated and flared off at the well head, and only liquid product was piped along for further processing. Using this setup, processing the gas as well as the liquid requires separators, compressors and dual pipelines. Rotary two-screw units are ideal for multiphase use, as they can pump any product that can be introduced into the suction passages of their screws. These devices also effectively handle heat generation from compressed gases. To select units for multiphase applications, an engineer should be familiar with these pumps and how they work. This article discusses rotary-screw pumps and how to effectively select a unit for multiphase service.

  6. Pumping and Breastmilk Storage

    MedlinePlus

    ... by washing your pumping equipment with soap and water and letting the equipment air dry. Storage of breastmilk Store your breastmilk in clean glass or hard BPA-free plastic bottles with tight-fitting lids. You can also use ...

  7. GAS METERING PUMP

    DOEpatents

    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.

  8. Pressurized Vessel Slurry Pumping

    SciTech Connect

    Pound, C.R.

    2001-09-17

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air.

  9. Sliding valve pump

    SciTech Connect

    Rupert, C.L.

    1980-09-09

    A sliding valve pump for oil wells which includes a working barrel having a plurality of apertures located in spaced relationship in the wall thereof and a pair of travelling valves fitted within the working barrel and carried by a plunger rod, the valves also having a plurality of apertures or ports for periodic registration with the ports in the working barrel wall to facilitate pumping of fluid from an oil reservoir or pool to the surface. The pump is designed to pull the oil-gas mixture from the reservoir pool into the lower section of the working barrel on the downward stroke, and to subsequently pump the collected oil through the barrel and tubing upwardly toward the surface on the upward stroke.

  10. Fuel injection pumps

    SciTech Connect

    Howes, P.

    1985-04-02

    A fuel injection pump of the rotary distributor type includes a cam actuated plunger housing in a bore and an adjustable fuel control member which varies the amount of fuel supplied to the bore. The pump also includes a timing piston connected to the cam, the piston being biased by a spring against the action of fuel under pressure. In order to vary the timing under certain conditions a control piston serves as an abutment for the spring and the application of pressure to the control piston is controlled by a valve which has a valve element coupled to a throttle member of the pump the valve having a housing which is secured on the exterior of the pump.

  11. High efficiency centrifugal pump

    SciTech Connect

    Nasvytis, P.J.; Jahrstorfer, G.W.

    1983-10-11

    A high speed fuel pump for a gas turnbine engine has a positively-driven shroud positioned between a main impeller and the wall of a pumping cavity to reduce impeller drag. The shroud is formed by a first disc having a boost impeller connected to its central hub portion and a second disc having a gear carried by its central hub portion. The main drive shaft assembly to which the main impeller is connected, carries a gear which meshes with gear mounted upon a shaft. The shaft also carries a gear which meshes with the gear. The gears are sized so that the shroud is driven at one-half the speed of the main impeller in order to maximize impeller drag reduction and enhance pumping capability when severe inlet conditions are present at the pump inlet.

  12. Absorption heat pump system

    DOEpatents

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  13. Direct nuclear pumped laser

    DOEpatents

    Miley, George H.; Wells, William E.; DeYoung, Russell J.

    1978-01-01

    There is provided a direct nuclear pumped gas laser in which the lasing mechanism is collisional radiated recombination of ions. The gas laser active medium is a mixture of the gases, with one example being neon and nitrogen.

  14. Using a Breast Pump

    MedlinePlus

    ... 15 seconds, then rinse with plenty of warm water. After washing, dry your hands thoroughly with a clean paper towel. You do not need to wash your breasts before you pump unless you have been using a cream, ointment, ...

  15. Underground pumped hydroelectric storage

    NASA Astrophysics Data System (ADS)

    Allen, R. D.; Doherty, T. J.; Kannberg, L. D.

    1984-07-01

    Underground pumped hydroelectric energy storage was conceived as a modification of surface pumped storage to eliminate dependence upon fortuitous topography, provide higher hydraulic heads, and reduce environmental concerns. A UPHS plant offers substantial savings in investment cost over coal-fired cycling plants and savings in system production costs over gas turbines. Potential location near load centers lowers transmission costs and line losses. Environmental impact is less than that for a coal-fired cycling plant. The inherent benefits include those of all pumped storage (i.e., rapid load response, emergency capacity, improvement in efficiency as pumps improve, and capacity for voltage regulation). A UPHS plant would be powered by either a coal-fired or nuclear baseload plant. The economic capacity of a UPHS plant would be in the range of 1000 to 3000 MW. This storage level is compatible with the load-velocity requirements of a greater metropolitan area with population of 1 million or more.

  16. Power scaling of mini-bar-based high-power 780-980nm pump modules at Spectra-Physics

    NASA Astrophysics Data System (ADS)

    Liu, Daming; Cutillas, Serge; Jin, Xu; Park, Sang-Ki; Johnson, Kelly; Li, Hanxuan; Truchan, Tom; Wolak, Ed; Towe, Terry; Chyr, Irving; Miller, Robert; Meissner, Arne; Lenarduzzi, Dino; Bullock, Robert; Mott, Jeff; Harrison, James

    2009-02-01

    Continued advances in high power diode laser technology enable new applications and enhance existing ones. Recently, mini-bar based modules have been demonstrated which combine the advantages of independent emitter failures previously shown in single-stripe architectures with the improved brightness retention enabled by multi-stripe architectures. In this work we highlight advances in a family of compact, environmentally rugged mini-bar based fiber coupled Orion modules. Advances in PCE (power conversion efficiency) and reliable operating power from a 9xx nm wavelength unit are shown from such modules. Additionally, highly reliable fiber coupled operation and performance data is demonstrated in other wavelengths in the 780 - 980 nm range. Data demonstrating the scaling this technology to 25W and higher power levels will be given.

  17. Photo-Thermally Induced Current Switching in Vanadium-Dioxide-Based Devices Using CO2 Laser Pumping.

    PubMed

    Kim, Jihoon; Jo, Songhyun; Park, Kyongsoo; Kim, Bong-Jun; Lee, Yong Wook

    2015-11-01

    By utilizing a CO2 laser as an illumination light source for triggering, we demonstrated bidirectional laser triggering in a two-terminal planar device based on a highly resistive vanadium dioxide (VO2) thin film. Bidirectional laser triggering between 0 and 10 mA was realized by switching the CO2 laser whose focused beam illuminated the VO2 film, and transient responses of laser-triggered devices were investigated when periodical laser pulses excited the VO2-based device at a variety of pulse widths and repetition rates. A switching contrast between off- and on-state currents was evaluated as -3333, and the rising and falling times were measured as -39 and -21 ms in the transient responses obtained by using periodic laser pulses with a pulse width of 100 ms, respectively.

  18. Remotely Adjustable Hydraulic Pump

    NASA Technical Reports Server (NTRS)

    Kouns, H. H.; Gardner, L. D.

    1987-01-01

    Outlet pressure adjusted to match varying loads. Electrohydraulic servo has positioned sleeve in leftmost position, adjusting outlet pressure to maximum value. Sleeve in equilibrium position, with control land covering control port. For lowest pressure setting, sleeve shifted toward right by increased pressure on sleeve shoulder from servovalve. Pump used in aircraft and robots, where hydraulic actuators repeatedly turned on and off, changing pump load frequently and over wide range.

  19. Geothermal irrigation pump

    SciTech Connect

    Matthews, H.B.

    1982-04-20

    A deep well pumping apparatus utilizing a geothermal source of energy is disposed within or above a stratum having a cool irrigating fluid, and an associated heat exchange unit is disposed within a stratum having the geothermal source. An organic working fluid is conveyed under pressure through the heat exchange unit and applied as a gas to a turbine assembly operatively coupled to the pump. The spent working fluid and cool irrigation fluid are then conveyed to the surface.

  20. Blue diode-pumped solid-state-laser based on ytterbium doped laser crystals operating on the resonance zero-phonon transition

    DOEpatents

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

    2001-01-01

    The invention provides an efficient, compact means of generating blue laser light at a wavelength near .about.493+/-3 nm, based on the use of a laser diode-pumped Yb-doped laser crystal emitting on its zero phonon line (ZPL) resonance transition at a wavelength near .about.986+/-6 nm, whose fundamental infrared output radiation is harmonically doubled into the blue spectral region. The invention is applied to the excitation of biofluorescent dyes (in the .about.490-496 nm spectral region) utilized in flow cytometry, immunoassay, DNA sequencing, and other biofluorescence instruments. The preferred host crystals have strong ZPL fluorecence (laser) transitions lying in the spectral range from .about.980 to .about.992 nm (so that when frequency-doubled, they produce output radiation in the spectral range from 490 to 496 nm). Alternate preferred Yb doped tungstate crystals, such as Yb:KY(WO.sub.4).sub.2, may be configured to lase on the resonant ZPL transition near 981 nm (in lieu of the normal 1025 nm transition). The laser light is then doubled in the blue at 490.5 nm.

  1. Addition of clidinium-C to the 14-day proton-pump inhibitor-based triple therapy for Helicobacter pylori eradication

    PubMed Central

    Seyyedmajidi, Mohammadreza; Homapoor, Saba; Zanganeh, Elahe; Dadjou, Mohammad; Eskandari Nejad, Shahab; Tajik Galayeri, Mohammad Hadi; Vafaeimanesh, Jamshid

    2016-01-01

    Background: Triple therapy with a proton pump inhibitor and two antibiotics in Helicobacter pylori (HP) eradication is widely accepted, but this combination fails in a considerable number of cases. The aim of this study was to assess the effect of clidinium-C addition on HP eradication and to investigate the efficacy and safety of clidinium-C in prevention of drugs' side effects. Methods: A total of 200 histopathologically confirmed HP positive peptic ulcer enrolled in this study which were randomly assigned to two treatment groups: OAC (20 mg omeprazole bid, 1000 mg amoxicillin bid and 500 mg clarithromycin bid) and OAC + clidinium-C. The effect of treatment and adverse effects were compared 6 weeks after completion of treatment. A13C-urea breath test was performed to confirm HP eradication. Results: A total of 184 patients (90 in group A and 94 in group B) completed the treatment protocols. HP eradication was achieved in 71.1% in OAC versus 72.3% in OCA+clidinium-C, (P=0.73). The frequencies of abdominal pain and stool abnormality, among the side effects recorded during the therapy period, were significantly lower in group B (OCA+clidinium-C) (P=0.01 and P=0.001, respectively). Conclusion: Addition of clidinium-C to OCA triple therapy decreases abdominal pain and frequency of stool abnormalities without affecting HP eradication rate. Based on these findings addition of clidinium-C may increase patient's compliance. PMID:27386057

  2. Axial pumps for propulsion systems

    NASA Technical Reports Server (NTRS)

    Huppert, M. C.; Rothe, K.

    1974-01-01

    The development of axial flow hydrogen pumps is examined. The design features and the performance data obtained during the course of the development programs are discussed. The problems created by the pump characteristics are analyzed. Graphs of four stage pump performance for various turbine blade configurations are developed. The characteristics and performance of a variety of pumps are included.

  3. The Evolution of Ion Pumps.

    ERIC Educational Resources Information Center

    Maloney, Peter C.; Wilson, T. Hastings

    1985-01-01

    Constructs an evolutionary sequence to account for the diversity of ion pumps found today. Explanations include primary ion pumps in bacteria, features and distribution of ATP-driven pumps, preference for cation transport, and proton pump reversal. The integrated evolutionary hypothesis should encourage new experimental approaches. (DH)

  4. Lattice Boltzmann simulations of lymphatic pumping

    NASA Astrophysics Data System (ADS)

    Kunert, Christian; Padera, Tim P.; Munn, Lance L.

    2012-02-01

    Lymphatic flow plays an important role in the progress of many diseases, including lymphedema and metastasis. However lymphatic pumping and flow is poorly understood. Here, we present a computer model that is based on biological observations of lymphatic pumping. Fluid flow is simulated by a D2Q9 lattice Boltzmann model. The boundary of the vessels moves according to shear-induced nitric oxide production, and wall motion transfers momentum to the fluid to induce flow. Because the model only includes local properties, it can be highly parallelized. In our case we utilize graphic processors (GPU) to achieve high performance computation. We show that the model provides stable pumping over a wide range of parameter values, with optimum flow achieved in the biological ranges. Furthermore, we investigate the efficiency by analyzing the flow rate and pumping frequency in order to compare the behavior of the model with existing in vivo data.

  5. Design considerations for bearingless rotary pumps.

    PubMed

    Kung, R T; Hart, R M

    1997-07-01

    The designs of rotary blood pumps have shown substantial technical progress over recent years, especially contact bearing designs. However, the concern for potential thromboembolism remains and can only be eliminated by the use of bearingless pumps. Bearingless designs can be achieved through the application of magnetic, hydrodynamic, and hydrostatic forces or a proper combination of these forces. Although a purely magnetically suspended, actively controlled system can be designed, judicious use of hydraulic forces can allow simplification of device configuration and control. In this study, bearingless designs were evaluated for both axial and centrifugal pump configurations. Trade-offs between shear rates and bearing leak rates were considered based upon constraints imposed by hemolysis and residence time. These principles were used for determining the design feasibility of a rotary pump using combined magnetic and hydraulic stabilizing forces.

  6. Horizontal pumping system installed at East Texas gas plant

    SciTech Connect

    Lopez, M.; Goodwin, B.

    1998-07-20

    Installation of horizontal, multistage centrifugal pumps in lean-amine service has proven successful and economical at Union Pacific Resources (UPR) East Texas gas plant (ETGP), Carthage, Tex. In the past, UPR had used either vertical can pumps or positive displacement (PD) pumps for amine circulation in gas-treating operations. When the need to replace a PD pump in the No. 4 amine plant arose, UPR solicited bids from both traditional pump suppliers. Additionally, UPR solicited a bid from REDA for its horizontal pumping system (HPS) based on previous success of this type of pump at ETGP for saltwater disposal. The first pump was installed in May 1996 and designed to circulate a maximum of 80 gpm. Since installation of the pump in No. 4 amine-treating unit, UPR has experienced no downtime and realized a significant cost savings on maintenance labor and parts over the previous positive displacement installation. The success of this HPS in amine service has led UPR to invest in five additional HPS pumps for ETGP`s amine service. The paper describes the decision, economics, pumping systems, preventive maintenance, and post installation performance.

  7. Well pump controller

    SciTech Connect

    Pikna, R. G.

    1985-04-02

    A device for automatically controlling the pumping of fluids from a well of the type using a walking beam and positive displacement pump to provide efficient utilization of the pumping equipment and energy required therefor, and to obtain efficient flow rates from the wall. A sensor detects the position of the walking beam at a predetermined position on the up-stroke of its pumping cycle and generates a signal to a control unit. a diaphram detects the pressure differential between the well casing pressure and the fluid delivery tube pressure. The diaphram moves a spring biased plunger which actuates a switch upon a predetermined pressure differential existing between the casing and delivery tube which sends a second signal to the control unit. The control unit upon receiving both signals maintains the pumping unit energizes until the pressure differential on the diaphram drops to a predetermined value preventing the plunger from actuating the switch. The control unit will deenergize the pumping unit if both signals are not received at the appropriate time. The sensitivity of the diaphram actuated switch is adjustable by changing the biasing force of the spring on the plunger.

  8. Pumping a playground swing.

    PubMed

    Post, Auke A; de Groot, Gert; Daffertshofer, Andreas; Beek, Peter J

    2007-04-01

    In mechanical studies of pumping a playground swing, two methods of energy insertion have been identified: parametric pumping and driven oscillation. While parametric pumping involves the systematic raising and lowering of the swinger's center of mass (CM) along the swing's radial axis (rope), driven oscillation may be conceived as rotation of the CM around a pivot point at a fixed distance to the point of suspension. We examined the relative contributions of those two methods of energy insertion by inviting 18 participants to pump a swing from standstill and by measuring and analyzing the swing-swinger system (defined by eight markers) in the sagittal plane. Overall, driven oscillation was found to play a major role and parametric pumping a subordinate role, although the relative contribution of driven oscillation decreased as swinging amplitude increased, whereas that of parametric pumping increased slightly. Principal component analysis revealed that the coordination pattern of the swing-swinger system was largely determined (up to 95%) by the swing's motion, while correlation analysis revealed that (within the remaining 5% of variance) trunk and leg rotations were strongly coupled.

  9. Satellite Propellant Pump Research

    NASA Technical Reports Server (NTRS)

    Schneider, Steven J.; Veres, Joseph P.; Hah, Chunill; Nerone, Anthony L.; Cunningham, Cameron C.; Kraft, Thomas G.; Tavernelli, Paul F.; Fraser, Bryan

    2005-01-01

    NASA Glenn initiated a satellite propellant pump technology demonstration program. The goal was to demonstrate the technologies for a 60 percent efficient pump at 1 gpm flow rate and 500 psia pressure rise. The pump design and analysis used the in-house developed computer codes named PUMPA and HPUMP3D. The requirements lead to a 4-stage impeller type pump design with a tip diameter of 0.54 inches and a rotational speed of 57,000 rpm. Analyses indicated that flow cavitation was not a problem in the design. Since the flow was incompressible, the stages were identical. Only the 2-stage pump was designed, fabricated, assembled, and tested for demonstration. Water was selected as the surrogate fluid for hydrazine in this program. Complete mechanical design including stress and dynamic analyses were conducted. The pump was driven by an electric motor directly coupled to the impellers. Runs up to 57,000 rpm were conducted, where a pressure rise of 200 psia at a flow rate of 0.8 gpm was measured to validate the design effort.

  10. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Benkowski, Robert J. (Inventor); Kiris, Cetin (Inventor); Kwak, Dochan (Inventor); Rosenbaum, Bernard J. (Inventor); Bacak, James W. (Inventor); DeBakey, Michael E. (Inventor)

    1999-01-01

    A blood pump that comprises a pump housing having a blood flow path therethrough, a blood inlet, and a blood outlet; a stator mounted to the pump housing, the stator having a stator field winding for producing a stator magnetic field; a flow straightener located within the pump housing, and comprising a flow straightener hub and at least one flow straightener blade attached to the flow straightener hub; a rotor mounted within the pump housing for rotation in response to the stator magnetic field, the rotor comprising an inducer and an impeller; the inducer being located downstream of the flow straightener, and comprising an inducer hub and at least one inducer blade attached to the inducer hub; the impeller being located downstream of the inducer, and comprising an impeller hub and at least one impeller blade attached to the impeller hub; and preferably also comprising a diffuser downstream of the impeller, the diffuser comprising a diffuser hub and at least one diffuser blade. Blood flow stagnation and clot formation within the pump are minimized by, among other things, providing the inducer hub with a diameter greater than the diameter of the flow straightener hub; by optimizing the axial spacing between the flow straightener hub and the inducer hub, and between the impeller hub and the diffuser hub; by optimizing the inlet angle of the diffuser blades; and by providing fillets or curved transitions between the upstream end of the inducer hub and the shaft mounted therein, and between the impeller hub and the shaft mounted therein.

  11. Pumping system for oil production

    SciTech Connect

    Yamato, I.; Yamata, T.

    1984-05-29

    A pumping system for oil production comprises a hydraulic unit set on the ground and adapted to send out a pressure oil, and a pump unit set in an oil well and adapted to draw up crude oil therefrom. The pump unit comprises a pump cylinder, and a plunger reciprocatingly moved in the pump cylinder. The plunger is provided with a clearance formed between the outer circumferential surface of a lower end portion thereof and the inner circumferential surface of the pump cylinder. The pressure oil supplied from the hydraulic unit is ejected from the clearance along the inner surface of the pump cylinder into a cylinder chamber.

  12. Apparatus for pumping subterranean fluids

    SciTech Connect

    Phillips, E. H.

    1985-11-19

    An apparatus and method for pumping oil or other fluids from the earth is disclosed as using a submersible pump which is suspended in a hole drilled into the earth by means of a flexible cable. Encased in a flexible sheath with the cable are a power cable for the pump and a flexible hose to carry the oil from the pump to the surface of the earth. Control and signal wires may also be encased in the sheath for connection to transducers mounted on the pump. The pump may be easily inserted into or removed from the hole by using a reeling mechanism on the surface of the earth. The pump itself may comprise a submersible motor connected to a rotary to linear motion transducer that causes a pump barrel to reciprocate. The pump barrel moves over a stationary pump plunger, and there are ball check valves in both the barrel and plunger to control the entrance and exit of oil.

  13. Automatic pump for deep wells

    SciTech Connect

    Brown, K.D.

    1981-11-24

    An automatic pump for deep wells comprises a long stroke reciprocating pump having its piston normally in its bottom position and an automatic control dependent upon the collection of a predetermined amount of liquid in the pump cylinder above the piston for actuating the piston to pump the liquid into a production line. The automatic control includes an electric motor driven hydraulic pump and a reservoir of hydraulic fluid which is actuated upon filling of the reciprocating pump chamber to supply hydraulic fluid to a closed chamber below the piston and force the piston upwardly to discharge liquid from the pump cylinder. Gas collected in the top of the pump cylinder results in low starting current and a saving of energy. The hydraulic pump is reversed automatically upon completion of the pumping stroke of the piston.

  14. Intracavity interferometry using synchronously pumped OPO

    NASA Astrophysics Data System (ADS)

    Zavadilová, Alena; Vyhlídal, David; Kubeček, Václav; Šulc, Jan; Navrátil, Petr

    2016-12-01

    The concept of system for intracavity interferometry based on the beat note detection in subharmonic synchronously intracavity pumped optical parametrical oscillator (OPO) is presented. The system consisted of SESAM-modelocked, picosecond, diode pumped Nd:YVO4 laser, operating at wavelength 1.06 μm and tunable linear intracavity pumped OPO based on MgO:PPLN crystal, widely tunable in 1.5 μm able to deliver two independent trains of picosecond pulses. The optical length of the OPO cavity was set to be exactly twice the pumping cavity length. In this configuration the OPO produces signal pulses with the same repetition frequency as the pump laser but the signal consists of two completely independent pulse trains. For purpose of pump probe measurements the setup signal with half repetition rate and scalable amplitude was derived from the OPO signal using RF signal divider, electropotical modulator and fiber amplifier. The impact of one pump beam on the sample is detected by one probing OPO train, the other OPO train is used as a reference. The beat note measured using the intracavity interferometer is proportional to phase modulation caused by the pump beam. The bandwidth of observed beat-note was less than 1 Hz (FWHM), it corresponds to a phase shift measurement error of less than 1.5 × 10-7 rad without any active stabilization. Such compact low-cost system could be used for ultra-sensitive phase-difference measurements (e.g. nonlinear refractive index measurement) for wide range of material especially in spectral range important for telecom applications.

  15. Well-pump alignment system

    DOEpatents

    Drumheller, D.S.

    1998-10-20

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump are disclosed, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping. 6 figs.

  16. New slurry pumps in China

    SciTech Connect

    Li, Z.; Wang, W.; Shi, Z.

    1998-07-01

    Wet parts of centrifugal slurry pumps are naturally subjected to wear, but local wear in pumps could be avoided, at least partly. Through studying the wear phenomenon of slurry pumps in industrial applications, a series of much more advanced slurry pumps was developed in China. Laboratory tests and industrial applications show that the new pumps are high in efficiency when transporting slurries, and uniform wear can be expected from them.

  17. New slurry pumps in China

    SciTech Connect

    Zhengwang Li; Wenlie Wang; Zhongyin Shi

    1998-04-01

    Wet parts of centrifugal slurry pumps are naturally subjected to wear, but local wear in pumps could be avoided, at least partly. Through studying the wear phenomenon of slurry pumps in industrial applications, a series of much more advanced slurry pumps was developed in China. Laboratory tests and industrial applications show that the new pumps are high in efficiency when transporting slurries, and uniform wear can be expected from them.

  18. Thermally Actuated Hydraulic Pumps

    NASA Technical Reports Server (NTRS)

    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

  19. ac electroosmotic pumping induced by noncontact external electrodes.

    PubMed

    Wang, Shau-Chun; Chen, Hsiao-Ping; Chang, Hsueh-Chia

    2007-09-21

    Electroosmotic (EO) pumps based on dc electroosmosis is plagued by bubble generation and other electrochemical reactions at the electrodes at voltages beyond 1 V for electrolytes. These disadvantages limit their throughput and offset their portability advantage over mechanical syringe or pneumatic pumps. ac electroosmotic pumps at high frequency (>100 kHz) circumvent the bubble problem by inducing polarization and slip velocity on embedded electrodes,1 but they require complex electrode designs to produce a net flow. We report a new high-throughput ac EO pump design based on induced-polarization on the entire channel surface instead of just on the electrodes. Like dc EO pumps, our pump electrodes are outside of the load section and form a cm-long pump unit consisting of three circular reservoirs (3 mm in diameter) connected by a 1x1 mm channel. The field-induced polarization can produce an effective Zeta potential exceeding 1 V and an ac slip velocity estimated as 1 mmsec or higher, both one order of magnitude higher than earlier dc and ac pumps, giving rise to a maximum throughput of 1 mulsec. Polarization over the entire channel surface, quadratic scaling with respect to the field and high voltage at high frequency without electrode bubble generation are the reasons why the current pump is superior to earlier dc and ac EO pumps.

  20. Fluid pumping system

    SciTech Connect

    Heath, R.T.; Gerlach, C.R.

    1986-05-13

    A fluid pumping system is described for use with a natural gas dehydrating system or the like having an absorber apparatus for removing water from wet natural gas to produce dry natural gas by use of a dessicant agent such as glycol, and a glycol treater apparatus for producing a source of dry glycol from wet glycol received from the absorber apparatus. The system consists of: a fluid pump means operatively connected between dry glycol source and absorber apparatus for pumping dry glycol from the dry glycol source to the absorber apparatus; a fluid operable piston motor means operatively associated with the pump means for driving the pump means and having fluid inlet passage means for receiving wet glycol from the absorber and fluid outlet passage means for delivering wet glycol to the glycol reboiler means wherein energy derived from the flow of fluid passing through the fluid inlet passage means provides the entire motivating force for the motor means and the pump means; the fluid pump means comprising a first pair of equal diameter chamber portion of a double acting piston means having a piston rod with two oppositely positioned piston heads at terminal ends thereof received within two oppositely positioned cylinders mounted on a fixed central body which slidably supports the piston rod; the fluid operable motor means comprising a second pair of equal diameter chamber portions of the double acting piston means; the effective areas of outwardly directed faces of the piston heads being substantially greater than the effective areas of inwardly directed faces of the piston heads; and a wet glycol passage shifting means associated with the fluid motor means for automatically changing the porting of the fluid motor means at the end of a piston stroke for producing reciprocal piston motion in the fluid motor means including toggle means actuated by the piston rod.