Sample records for eurotrans 150kw cw

  1. Discrete dynamics on noncommutative CW complexes

    Directory of Open Access Journals (Sweden)

    Vida Milani


    Full Text Available The concept of discrete multivalued dynamical systems for noncommutative CW complexes is developed. Stable and unstable manifolds are introduced and their role in geometric and topological configurations of noncommutative CW complexes is studied. Our technique is illustrated by an example on the noncommutative CW complex decomposition of the algebra of continuous functions on two dimensional torus.

  2. CW CO2 Laser Induced Chemical Reactions (United States)

    Pola, Joseph


    CW CO2 laser driven reactions between sulfur hexafluoride and carbon oxide, carbon suboxide, carbonyl sulfide and carbon disulfide proceed at subatmospheric pressures and yield fluorinated carbon compounds and sulfur tetrafluoride. CW CO2 laser driven reactions of organic compounds in the presence of energy-conveying sulfur hexafluoride show reaction course different from that normally observed due to elimination of reactor hot surface effects. The examples concern the decomposition of polychlorohydrocarbons, 2-nitropropane, tert.-butylamine, allyl chloride, spirohexane, isobornyl acetate and the oxidation of haloolefins. CW CO2 laser induced fragmentation of 1-methyl-l-silacyclobutanes and 4-silaspiro(3.4)octane in the presence of sulfur hexafluoride is an effective way for preparation and deposition of stable organosilicon polymers.

  3. New high power CW klystrons at TED

    CERN Document Server

    Beunas, A; Marchesin, R


    Thales Electron Devices (TED) has been awarded a contract by CERN to develop and produce 20 units of the klystrons needed to feed the Large Hadrons Collider (LHC). Each of these delivers 300 kW of CW RF power at 400 MHz. Three klystrons have been delivered to CERN up to now.

  4. Large Scale CW ECRH Systems: Some considerations

    Directory of Open Access Journals (Sweden)

    Turkin Y.


    Full Text Available Electron Cyclotron Resonance Heating (ECRH is a key component in the heating arsenal for the next step fusion devices like W7-X and ITER. These devices are equipped with superconducting coils and are designed to operate steady state. ECRH must thus operate in CW-mode with a large flexibility to comply with various physics demands such as plasma start-up, heating and current drive, as well as configurationand MHD - control. The request for many different sophisticated applications results in a growing complexity, which is in conflict with the request for high availability, reliability, and maintainability. ‘Advanced’ ECRH-systems must, therefore, comply with both the complex physics demands and operational robustness and reliability. The W7-X ECRH system is the first CW- facility of an ITER relevant size and is used as a test bed for advanced components. Proposals for future developments are presented together with improvements of gyrotrons, transmission components and launchers.

  5. Bandwidth reduction in CW fiber Raman lasers (United States)

    Labudde, P.; Weber, H. P.; Stolen, R. H.


    The oscillation linewidth of CW fiber Raman lasers has been reduced from typical uncontrolled values of 200 GHz (approximately 0.2 nm for 528 nm radiation) to 9 GHz by employing prisms, gratings, and etalons in various resonator configurations. Further reduction is limited by four-wave mixing and stimulated Brillouin scattering. Although four-wave mixing limits bandwidth reduction, the results demonstrate the use of this nonlinear process for intensity stabilization.

  6. Prediction of free field heave using CW and CH indices

    Directory of Open Access Journals (Sweden)

    Niedźwiedzka Karina


    Full Text Available Prediction of free field heave using CW and CH indices. In order to predict free heave in expansive silty clays two methods were applied: CLOD test and double-swelling methods. In both methods CW and CH indices are required respectively to determine the soil heave. The CW index is determined as a slope of straight line of shrinkage curve obtained with a use of CLOD test. In case of double-swelling method two oedometer tests were carried out to determine CH index: constantvolume and consolidation-swell oedometer tests. Comparison between heave values calculated using CW and CH indexes indicated slight differences.

  7. Splitting of high power, cw proton beams

    CERN Document Server

    Facco, Alberto; Berkovits, Dan; Yamane, Isao; 10.1103/PhysRevSTAB.10.091001


    A simple method for splitting a high power, continuous wave (cw) proton beam in two or more branches with low losses has been developed in the framework of the EURISOL (European Isotope Separation On-Line adioactive Ion Beam Facility) design study. The aim of the system is to deliver up to 4 MW of H beam to the main radioactive ion beam production target, and up to 100 kWof proton beams to three more targets, simultaneously. A three-step method is used, which includes magnetic neutralization of a fractionof the main H- beam, magnetic splitting of H- and H0, and stripping of H0 to H+. The method allowsslow raising and individual fine adjustment of the beam intensity in each branch.

  8. Two-color CW STED nanoscopy (United States)

    Chen, Xuanze; Liu, Yujia; Yang, Xusan; Wang, Tingting; Alonas, Eric; Santangelo, Philip J.; Ren, Qiushi; Xi, Peng


    Fluorescent microscopy has become an essential tool to study biological molecules, pathways and events in living cells, tissues and animals. Meanwhile even the most advanced confocal microscopy can only yield optical resolution approaching Abbe diffraction limit of 200 nm. This is still larger than many subcellular structures, which are too small to be resolved in detail. These limitations have driven the development of super-resolution optical imaging methodologies over the past decade. In stimulated emission depletion (STED) microscopy, the excitation focus is overlapped by an intense doughnut-shaped spot to instantly de-excite markers from their fluorescent state to the ground state by stimulated emission. This effectively eliminates the periphery of the Point Spread Function (PSF), resulting in a narrower focal region, or super-resolution. Scanning a sharpened spot through the specimen renders images with sub-diffraction resolution. Multi-color STED imaging can present important structural and functional information for protein-protein interaction. In this work, we presented a two-color, synchronization-free STED microscopy with a Ti:Sapphire oscillator. The excitation wavelengths were 532nm and 635nm, respectively. With pump power of 4.6 W and sample irradiance of 310 mW, we achieved super-resolution as high as 71 nm. Human respiratory syncytial virus (hRSV) proteins were imaged with our two-color CW STED for co-localization analysis.

  9. A Stepped Frequency CW SAR for Lightweight UAV Operation

    National Research Council Canada - National Science Library

    Morrison, Keith


    A stepped-frequency continuous wave (SF-CW) synthetic aperture radar (SAR), with frequency-agile waveforms and real-time intelligent signal processing algorithms, is proposed for operation from a lightweight UAV platform...

  10. Analytic Performance Evaluation Design of the MFACP CW Normalizer (United States)


    Gilbert, D. C. - "Algorithm and Software Specification for ACP CW Detection and Tracking," Analysis and Tecnology , Inc., Report no. P-4569-1-91, 31...Dec 91. 3. Gilbert, D. C. - "Automatic Detection Algorithm for ACP CW Processing," Analysis and Tecnology , Inc., Tech. Memo. 90:32/27-34A, 30 Nov 90. 4...J. - "An Analytical Design and Evaluation Methodology for Active SONAR Normalizers (PRELIMINARY),"Analysis and Tecnology , Engineering Technology

  11. First experiments with gasdynamic ion source in CW mode

    Energy Technology Data Exchange (ETDEWEB)

    Skalyga, V., E-mail:; Vodopyanov, A. [Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), 46 Ul‘yanova St., Nizhny Novgorod 603950 (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina St., Nizhny Novgorod 603950 (Russian Federation); Izotov, I.; Golubev, S. [Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), 46 Ul‘yanova St., Nizhny Novgorod 603950 (Russian Federation); Tarvainen, O. [Department of Physics, University of Jyvaskyla, P.O. Box 35 (YFL), 40500 Jyvaskyla (Finland)


    A new type of ECR ion source—a gasdynamic ECR ion source—has been recently developed at the Institute of Applied Physics. The main advantages of such device are extremely high ion beam current with a current density up to 600–700 emA/cm{sup 2} in combination with low emittance, i.e., normalized RMS emittance below 0.1 π mm mrad. Previous investigations were carried out in pulsed operation with 37.5 or 75 GHz gyrotron radiation with power up to 100 kW at SMIS 37 experimental facility. The present work demonstrates the first experience of operating the gasdynamic ECR ion source in CW mode. A test bench of SMIS 24 facility has been developed at IAP RAS. 24 GHz radiation of CW gyrotron was used for plasma heating in a magnetic trap with simple mirror configuration. Initial studies of plasma parameters were performed. Ion beams with pulsed and CW high voltage were successfully extracted from the CW discharge. Obtained experimental results demonstrate that all advantages of the gasdynamic source can be realized also in CW operation.

  12. Noise considerations for vital signs CW radar sensors

    DEFF Research Database (Denmark)

    Jensen, Brian Sveistrup; Jensen, Thomas; Zhurbenko, Vitaliy


    The use of continuous wave (CW) radars for measuring human vital signs have recently received a lot of attention due to its many promising applications like monitoring people at hospitals or infants at home without the need for wired sensors. This paper briefly presents the typical CW radar setup...... and the underlying signal theory for such sensors. Then to point out and especially clarify one of the most important effects aiding the design of vital signs radars (VSR), a more detailed discussion concerning phase noise cancellation (or filtering) by range correlation is given. This discussion leads to some...

  13. CW ND:YAG laser welding of dissimilar sheet metals

    CSIR Research Space (South Africa)

    Theron, M


    Full Text Available A 4kW CW Nd:YAG laser was used for lap welding of three different dissimilar sheet metal combinations, namely 316L S/S - Ti64, 316L S/S - Al 5251 and Al 1200 – Cu (99.85%). A welding matrix of laser power, travel speed and spot sizes...

  14. IOT RF Power Sources for Pulsed and CW Linacs

    CERN Document Server

    Bohlen, H P


    For many years, klystrons have been the preferred RF power amplifiers for both pulsed and CW linacs at UHF and higher frequencies. Their properties have earned them that position. But in recent years in UHF terrestrial television transmitters the earlier predominant klystron has been replaced the Inductive Output Tube (IOT) because the IOT provides higher efficiency and, due to its excellent linearity, can handle the simultaneous amplification of both the vision and the sound signal. Its robustness and life expectancy equals that of a klystron, and it more than compensates its lower gain by a lower price and a smaller size. For linac operation, derivates of UHF TV IOTs, capable of up to 80 kW CW output power, are already available and operating. In L-Band, they are presently joined by recently developed 15 to 30 kW CW IOTs. HOM-IOTs are expected to extend the CW range in UHF to 1 MW and beyond. Pulsed operation of an IOT can be achieved without a high-voltage modulator. Since the beam current is grid-controll...

  15. SAR: A novel application for FM-CW radars

    NARCIS (Netherlands)

    Wit, J.J.M. de; Hoogeboom, P.


    For small-scale earth observation applications, there ia a special interest in low-cost, high-resolution imaging radars small, enough to be operated from small, possibly unmanned aircraft. The combination of FM-CW technology and the high resolution of SAR systems should result in such a small,

  16. Applications of KHZ-CW Lidar in Ecological Entomology (United States)

    Malmqvist, Elin; Brydegaard, Mikkel


    The benefits of kHz lidar in ecological entomology are explained. Results from kHz-measurements on insects, carried out with a CW-lidar system, employing the Scheimpflug principle to obtain range resolution, are presented. A method to extract insect events and analyze the large amount of lidar data is also described.

  17. Singly resonant cw OPO with simple wavelength tuning. (United States)

    Vainio, Markku; Peltola, Jari; Persijn, Stefan; Harren, Frans J M; Halonen, Lauri


    A singly resonant continuous-wave optical parametric oscillator (cw OPO) is described. The OPO contains no intracavity etalon, which makes its wavelength tuning simple and straightforward, including only temperature tuning of the nonlinear crystal and wavelength tuning of the pump laser. The OPO provides watt-level output in the mid-infrared region and operates reliably without mode hops for several hours.

  18. Large scale CW ECRH systems: Meeting a challenge

    NARCIS (Netherlands)

    Erckmann, V.; Kasparek, W.; Plaum, B.; Lechte, C.; Petelin, M.I.; Bruschi, A.; D'Arcangelo, O.; Bin, W.; Braune, H.; Braber, R. van den; Doelman, N.J.; Gantenbein, G.; Laqua, H.P.; Lubiako, L.; Marushchenko, N.B.; Michel, G.; Thumm, M.; Stuttgart, I.


    Electron Cyclotron Resonance Heating (ECRH) systems for next step-fusion devices like W7-X and ITER operate in CW-mode and provide a large flexibility to comply with various physics demands such as plasma start-up, heating and current drive, as well as configuration and MHD control. The request for

  19. Motion Compensation for a High Resolution Ka-Band Airborne FM-CW SAR

    NARCIS (Netherlands)

    Meta, A; Lorga, J.F.M.; Wit, J.J.M. de; Hoogeboom, P.


    Airborne synthetic aperture radar is a promising new application for FM-CW radars. At the IRCTR, an operational demonstrator system has been developed in order to investigate the practicability of FM-CW SAR and to prove that an FM-CW SAR system can be operated in an efficient manner from a small

  20. Performance Analysis of a High Resolution Airborne FM-CW Synthetic Aperture Radar

    NARCIS (Netherlands)

    Wit, J.J.M. de; Hoogeboom, P.


    Compact FM-CW technology combined with high resolution SAR techniques should pave the way for a small and cost effective imaging radar. A research project has been inìtiated to investigate the feasibility of FM-CW SAR. Within the framework of the project an operational airborne FM-CW SAR


    Energy Technology Data Exchange (ETDEWEB)

    Robert Rimmer


    Steady development in SRF accelerator technology combined with the success of large scale installations such as CEBAF at Jefferson Laboratory and the SNS Linac at ORNL gives credibility to the concept of very high average power CW machines for light sources or Proton drivers. Such machines would be powerful tools for discovery science in themselves but could also pave the way to reliable cost effective drivers for such applications as neutrino factories, an energy-frontier muon collider, nuclear waste transmutation or accelerator driven subcritical reactors for energy production. In contrast to machines such as ILC that need maximum accelerating gradient, the challenges in these machines are mainly in efficiency, reliability, beam stability, beam loss and of course cost. In this paper the present state of the art is briefly reviewed and options for a multi-GeV, multi-MW CW linac are discussed.

  2. LOT-G3: Plasma Lamp, Ozonator and CW transmitter

    CERN Document Server

    Gobato, Ricardo; Gobato, Alekssander


    The LOT-G3 is designed to be a versatile equipment that perform several simple experiments for use in helping the physics classes for high school. Easy construction, low cost, using easily accessible materials. Its construction involves simple practices and knowledge of electromagnetism. It has the function of a plasma globe to demonstrate the ionization of a low pressure gas, as well as the formation of magnetic field. Can be used as sanitizer closed environments such as automotive vehicles in ozonator function, demonstrating the ionization of oxygen in the atmosphere, producing ozone, essential to life on earth. And as a sparks transmitter, low power, low frequency modulated continuous wave in (CW), for signals in Morse code. Therefore the equipment here called LOT-G3, has three functions: a plasma lamp, ozonator and CW transmitter.

  3. CW-to-pulse conversion using temporal Talbot array illuminators. (United States)

    Fernández-Pousa, Carlos R; Maram, Reza; Azaña, José


    We report on the linear conversion of continuous-wave (CW) laser light to optical pulses using temporal Talbot array illuminators (TAIs) with fractional orders 1/q(q≤10), implemented by use of multilevel PM and dispersive propagation in a chirped fiber Bragg grating. The generated, sub-nanosecond optical pulse trains have repetition rates in the gigahertz range and show the presence of satellite pulses originated by the finite electrical modulation bandwidth (7.5 GHz). Though this fact impacts the resulting extinction ratio, an experimental comparison with time and Fresnel lenses indicates that temporal TAIs represent compact systems with high light gathering efficiency (>87%) at moderate values of compression (q≤8), which can be tailored in repetition rate, gain, or width, through the fractional Talbot order for its use in pulse compression systems fed by CW light.

  4. Laser Photon Force Measurements using a CW Laser (United States)

    Gray, Perry; Edwards, David L.; Carruth, M. Ralph, Jr.; Munafo, Paul M. (Technical Monitor)


    The photon force resulting from the non-damaging impact of laser derived photons on a metallic target was measured using a vacuum compatible microbalance. This experiment quantitatively verified that the force resulting from laser photons impacting a reflective surface is measurable and predictable. The photon wavelength is 1064 mn and the laser is a multi-mode 30OW Nd YAG continuous wave (CW) laser.

  5. A Variable Energy CW Compact Accelerator for Ion Cancer Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, Carol J. [Fermilab; Taylor, J. [Huddersfield U.; Edgecock, R. [Huddersfield U.; Schulte, R. [Loma Linda U.


    Cancer is the second-largest cause of death in the U.S. and approximately two-thirds of all cancer patients will receive radiation therapy with the majority of the radiation treatments performed using x-rays produced by electron linacs. Charged particle beam radiation therapy, both protons and light ions, however, offers advantageous physical-dose distributions over conventional photon radiotherapy, and, for particles heavier than protons, a significant biological advantage. Despite recognition of potential advantages, there is almost no research activity in this field in the U.S. due to the lack of clinical accelerator facilities offering light ion therapy in the States. In January, 2013, a joint DOE/NCI workshop was convened to address the challenges of light ion therapy [1], inviting more than 60 experts from diverse fields related to radiation therapy. This paper reports on the conclusions of the workshop, then translates the clinical requirements into accelerat or and beam-delivery technical specifications. A comparison of available or feasible accelerator technologies is compared, including a new concept for a compact, CW, and variable energy light ion accelerator currently under development. This new light ion accelerator is based on advances in nonscaling Fixed-Field Alternating gradient (FFAG) accelerator design. The new design concepts combine isochronous orbits with long (up to 4m) straight sections in a compact racetrack format allowing inner circulating orbits to be energy selected for low-loss, CW extraction, effectively eliminating the high-loss energy degrader in conventional CW cyclotron designs.

  6. Design and calibration of a CW coherent laser radar (United States)

    Claesson, T.; Gullberg, K.; Letalick, D.; Renhorn, I.; Steinvall, O.; Widen, A.


    The design, calibration and performance of a CW coherent laser radar testbed system is described. Detector responsiveness and detector noise in a heterodyne system is considered. A detailed evaluation of beam propagation and phase front matching is given. The final system is supplemented with a digital image memory, a galvanometer scanner and a boresighted TV camera. Analysis of images obtained indoors from a diffuse reference target reveal the well known Rayleigh statistics for the signal amplitude and speckle "cells' which on the average have a diameter equal to the tranceiver aperture. The influence of atmospheric turbulence on transmitter beam size and signal fluctuations is studied over a 500 m path.

  7. The CW domain, a structural module shared amongst vertebrates, vertebrate-infecting parasites and higher plants. (United States)

    Perry, Jason; Zhao, Yunde


    A previously undetected domain, named CW for its conserved cysteine and tryptophan residues, appears to be a four-cysteine zinc-finger motif found exclusively in vertebrates, vertebrate-infecting parasites and higher plants. Of the twelve distinct nuclear protein families that comprise the CW domain-containing superfamily, only the microrchida (MORC) family has begun to be characterized. However, several families contain other domains suggesting a relationship between the CW domain and either chromatin methylation status or early embryonic development.

  8. Evaluation of a unique cw laser in radial thermokeratoplasty (United States)

    Smithpeter, Colin L.; Welch, Ashley J.; Rylander, Henry G., III


    A unique continuous wave (cw) holmium laser ((lambda) equals 2.09 micrometers , Rare Earth Medical) has been evaluated as a new heating modality for thermokeratoplasty. Thermokeratoplasty is a refractive surgical procedure for the correction of hyperopia which uses selective heating to reshape the cornea. The holmium laser is highly effective in this procedure due to the high absorption coefficient ((mu) a equals 27.55 cm-1) of the cornea at 2.09 micrometers . The depth of corneal photocoagulation has been evaluated with histological studies of enucleated porcine eyes that were irradiated with the cw Ho:YAG laser. Laser power and exposure time ranged from 300 mW to 800 mW and 100 ms to 800 ms, respectively. The laser was delivered to the eyes via a 600 micrometers low-OH optical fiber. Coagulation depth was determined by birefringence microscopy of the corneal sections. Our studies also compared the effects of contact and non-contact irradiation and found significant advantages with the contact mode. The optimal laser parameters determined from the histology studies were used for in vivo rabbit studies to quantify the refractive correction possible. One coagulation was placed on each of sixteen equiangular rays taken from a central, clear, optical zone in the cornea with a diameter of 7 mm. Refractive changes in the central cornea were quantified with a keratoscope. Initial procedures resulted in refractive changes up to five diopters. The keratoscope results showed a significant regression at three weeks post- operatively.

  9. An Acoustic Demonstration Model for CW and Pulsed Spectrosocopy Experiments (United States)

    Starck, Torben; Mäder, Heinrich; Trueman, Trevor; Jäger, Wolfgang


    High school and undergraduate students have often difficulties if new concepts are introduced in their physics or chemistry lectures. Lecture demonstrations and references to more familiar analogues can be of great help to the students in such situations. We have developed an experimental setup to demonstrate the principles of cw absorption and pulsed excitation - emission spectroscopies, using acoustical analogues. Our radiation source is a speaker and the detector is a microphone, both controlled by a computer sound card. The acoustical setup is housed in a plexiglas box, which serves as a resonator. It turns out that beer glasses are suitable samples; this also helps to keep the students interested! The instrument is controlled by a LabView program. In a cw experiment, the sound frequency is swept through a certain frequency range and the microphone response is recorded simultaneously as function of frequency. A background signal without sample is recorded, and background subtraction yields the beer glass spectrum. In a pulsed experiment, a short sound pulse is generated and the microphone is used to record the resulting emission signal of the beer glass. A Fourier transformation of the time domain signal gives then the spectrum. We will discuss the experimental setup and show videos of the experiments.

  10. Optimal Signal Processing of Frequency-Stepped CW Radar Data (United States)

    Ybarra, Gary A.; Wu, Shawkang M.; Bilbro, Griff L.; Ardalan, Sasan H.; Hearn, Chase P.; Neece, Robert T.


    An optimal signal processing algorithm is derived for estimating the time delay and amplitude of each scatterer reflection using a frequency-stepped CW system. The channel is assumed to be composed of abrupt changes in the reflection coefficient profile. The optimization technique is intended to maximize the target range resolution achievable from any set of frequency-stepped CW radar measurements made in such an environment. The algorithm is composed of an iterative two-step procedure. First, the amplitudes of the echoes are optimized by solving an overdetermined least squares set of equations. Then, a nonlinear objective function is scanned in an organized fashion to find its global minimum. The result is a set of echo strengths and time delay estimates. Although this paper addresses the specific problem of resolving the time delay between the first two echoes, the derivation is general in the number of echoes. Performance of the optimization approach is illustrated using measured data obtained from an HP-X510 network analyzer. It is demonstrated that the optimization approach offers a significant resolution enhancement over the standard processing approach that employs an IFFT. Degradation in the performance of the algorithm due to suboptimal model order selection and the effects of additive white Gaussion noise are addressed.

  11. Variable Power, Short Microwave Pulses Generation using a CW Magnetron

    Directory of Open Access Journals (Sweden)

    CIUPA, R.


    Full Text Available Fine control of microwave power radiation in medical and scientific applications is a challenging task. Since a commercial Continuous Wave (CW magnetron is the most inexpensive microwave device available today on the market, it becomes the best candidate for a microwave power generator used in medical diathermy and hyperthermia treatments or high efficiency chemical reactions using microwave reactors as well. This article presents a new method for driving a CW magnetron with short pulses, using a modified commercial Zero Voltage Switching (ZVS inverter, software driven by a custom embedded system. The microwave power generator designed with this method can be programmed for output microwave pulses down to 1% of the magnetron's power and allows microwave low frequency pulse modulation in the range of human brain electrical activity, intended for medical applications. Microwave output power continuous control is also possible with the magnetron running in the oscillating area, using a dual frequency Pulse Width Modulation (PWM, where the low frequency PWM pulse is modulating a higher resonant frequency required by the ZVS inverter's transformer. The method presented allows a continuous control of both power and energy (duty-cycle at the inverter's output.

  12. Slot-coupled CW standing wave accelerating cavity (United States)

    Wang, Shaoheng; Rimmer, Robert; Wang, Haipeng


    A slot-coupled CW standing wave multi-cell accelerating cavity. To achieve high efficiency graded beta acceleration, each cell in the multi-cell cavity may include different cell lengths. Alternatively, to achieve high efficiency with acceleration for particles with beta equal to 1, each cell in the multi-cell cavity may include the same cell design. Coupling between the cells is achieved with a plurality of axially aligned kidney-shaped slots on the wall between cells. The slot-coupling method makes the design very compact. The shape of the cell, including the slots and the cone, are optimized to maximize the power efficiency and minimize the peak power density on the surface. The slots are non-resonant, thereby enabling shorter slots and less power loss.

  13. Apsidal Motion Study of Close Binary System CW Cephei

    Directory of Open Access Journals (Sweden)

    Wonyong Han


    Full Text Available New observations for the times of minimum lights of a well-known apsidal motion star CW Cephei were made using a 0.6 m wide field telescope at Jincheon station of Chungbuk National University Observatory, Korea during the 2015 observational season. We determined new times of minimum lights from these observations and analyzed O-C diagrams together with collected times of minima to study both the apsidal motion and the Light Time Effect (LTE suggested in the system. The new periods of the apsidal motion and the LTE were calculated as 46.6 and 39.3 years, respectively, which were similar but improved accuracy than earlier ones investigated by Han et al. (2002, Erdem et al. (2004 and Wolf et al. (2006.

  14. Concepts for the JLab Ampere-Class CW Cryomodule

    CERN Document Server

    Rimmer, Robert; Henry, James; Hicks, William R; Preble, Joseph P; Stirbet, Mircea; Wang, Haipeng; Wilson, Katherine; Wu, Genfa


    We describe the concepts and developments underway at JLab as part of the program to develop a new CW cryomodule capable of transporting ampere-level beam currents in a compact FEL. Requirements include real-estate gradient of at least 10 MV/m and very strong HOM damping to push BBU thresholds up by two or more orders of magnitude compared to existing designs. Cavity shape, HOM damping, power couplers, tuners etc. are being designed and optimized for this application. Cavity considerations include a large iris for beam halo, low-RF losses, HOM frequencies and Q's, low peak surface fields, field flatness and microphonics. Module considerations include high packing factor, low static heat leak, image current heating of beam-line components, cost and maintainability. This module is being developed for the next generation ERL based high power FELs but may be useful for other applications such as electron cooling, electron-ion colliders, industrial processing etc.

  15. Operational experience with CW high gradient and high QL cryomodules

    Energy Technology Data Exchange (ETDEWEB)

    Hovater, J. Curt [JLAB; Allison, Trent L. [JLAB; Bachimanchi, Ramakrishna [JLAB; Daly, Edward F. [JLAB; Drury, Michael A. [JLAB; Lahti, George E. [JLAB; Mounts, Clyde I. [JLAB; Nelson, Richard M. [JLAB; Plawski, Tomasz E. [JLAB


    The Continuous Electron Beam Accelerator Facility (CEBAF) energy upgrade from 6 GeV to 12 GeV includes the installation of ten new 100 MV cryomodules (80 cavities). The superconducting RF cavities are designed to operate CW at an accelerating gradient of 19.3 MV/m with a QL of 3×107. The RF system employs single cavity control using new digital LLRF controls and 13 kW klystrons. Recently, all of the new cryomodules and associated RF hardware and software have been commissioned and operated in the CEBAF accelerator. Electrons at linac currents up to 10 ?A have been successfully accelerated and used for nuclear physics experiments. This paper reports on the commissioning and operation of the cryomodules and RF system.

  16. Effect of Nd 3+concentration on CW and pulsed performance of fiber ...

    Indian Academy of Sciences (India)

    The effect of Nd3+ concentration on the CW and Q-switched laser performances at 1064 nm from Nd : YVO4 has been studied under diode laser pumping in identical laser configuration. The Nd3+ concentrations used were 1, 2 and 3 at. % in YVO4 crystals. Under the CW operations we have compared the thermal lensing ...

  17. Airborne FM-CW SAR and Integrated Navigation System Data Fusion

    NARCIS (Netherlands)

    Lorga, J.F.M.; Meta, A.; Wit, J.J.M. de; Mulder, J.A.


    The combination of compact FM-CW radar technology and high resolution SAR pro- cessing techniques should pave the way for the development of a small and cost e®ective imaging radar with high resolution. However, airborne SAR is a very novel application for FM-CW radars. In order to investigate the

  18. Modified Range-Doppler Processing for FM-CW Synthetic Aperture Radar

    NARCIS (Netherlands)

    Wit, J.J.M. de; Meta, A.; Hoogeboom, P.


    The combination of compact frequency-modulated continuous-wave (FM-CW) technology and high-resolution synthetic aperture radar (SAR) processing techniques should pave the way for the development of a lightweight, cost-effective, high-resolution, airborne imaging radar. Regarding FM-CW SAR signal

  19. Development of a High Resolution Airborne Millimeter Wave FM-CW SAR

    NARCIS (Netherlands)

    Meta, A.; Wit, J.J.M. de; Hoogeboom, P.


    The combination of compact FM-CW radar technology and high resolution SAR processing techniques should pave the way for the development of a small, lightweight and cost effective imaging radar. In the field of airborne earth observation, SAR is however a novel application for FM-CW radars. At IRCTR

  20. A new approach to model CW CO2 laser using rate equations

    Indian Academy of Sciences (India)


    Nov 11, 2016 ... assumption of the different modes to be in thermal equilibrium. Moore et al [8] and Tychinskii [9] were the first to independently propose these rate equations for the CW CO2 laser. Tyte [10] used such a model to calculate population densities of the vibration lev- els of a CW CO2 laser, in the non-lasing case.

  1. Data of evolutionary structure change: 1VLCA-1CW1A [Confc[Archive

    Lifescience Database Archive (English)


  2. High-power pulsed and CW diode-pumped mode-locked Nd:YAG lasers (United States)

    Marshall, Larry R.; Hays, A. D.; Kaz, Alex; Kasinski, Jeff; Burnham, R. L.


    The operation of both pulsed and CW diode-pumped mode-locked Nd:YAG lasers are presented. The pulsed laser produced 1.0 mJ with pulsewidths of 90 psec at 20 Hz. The CW pumped laser produced 6 W output at 1.064 microns and 3 W output at 532 nm.

  3. Detailed characterization of CW- and pulsed-pump four-wave mixing in highly nonlinear fibers

    DEFF Research Database (Denmark)

    Lillieholm, Mads; Galili, Michael; Grüner-Nielsen, L.


    We present a quantitative comparison of continuouswave- (CW) and pulsed-pump four-wave mixing (FWM) in commercially available highly nonlinear fibers (HNLFs), and suggest properties for which the CW and pulsed FWM bandwidths are limited in practice. The CWand pulsed-pump parametric gain is charac......We present a quantitative comparison of continuouswave- (CW) and pulsed-pump four-wave mixing (FWM) in commercially available highly nonlinear fibers (HNLFs), and suggest properties for which the CW and pulsed FWM bandwidths are limited in practice. The CWand pulsed-pump parametric gain...... bandwidth. However, an inverse scaling of the TOD with the dispersion fluctuations, leads to different CW-optimized fibers, which depend only on the even dispersion-orders....

  4. Identification of a novel HLA-C allele, Cw*0406, in a Singapore Malay. (United States)

    Ren, E C; Haniff, F; Loh, M T; Chan, S H; Petersdorf, E; Hansen, J


    A novel allele, C*0406, has been identified and is characterised by a single nucleotide substitution at position 196 of exon 3 when compared with its closest related allele, C*0403. The latter is found in 4/69 Chinese and 7/80 Malays while Cw*0406 was found in only one Malay individual within the study populations. The data suggest that Cw*0406 may have arisen as a relatively recent genetic event either by gene conversion or as a simple point mutation variant of Cw*0403.

  5. Design and operation of 140 GHz gyrotron oscillators for power levels up to 1 MW CW

    Energy Technology Data Exchange (ETDEWEB)

    Jory, H.; Bier, R.; Craig, L.J.; Felch, K.; Ives, L.; Lopez, N.; Spang, S.


    Varian has designed and tested 140 GHz gyrotron oscillators that have generated output powers of 100 kW CW and 200 kW for 1 ms pulses. Upcoming tubes will be designed to operate at power levels of 200 kW CW and ultimately up to 1 MW CW. The important design considerations which are addressed in the higher power tubes include the design of the electron gun, interaction circuit, and output window. These issues will be discussed and the results of the earlier 140 GHz gyrotron work at Varian will be summarized.

  6. Eighth CW and High Average Power RF Workshop

    CERN Document Server


    We are pleased to announce the next Continuous Wave and High Average RF Power Workshop, CWRF2014, to take place at Hotel NH Trieste, Trieste, Italy from 13 to 16 May, 2014. This is the eighth in the CWRF workshop series and will be hosted by Elettra - Sincrotrone Trieste S.C.p.A. ( CWRF2014 will provide an opportunity for designers and users of CW and high average power RF systems to meet and interact in a convivial environment to share experiences and ideas on applications which utilize high-power klystrons, gridded tubes, combined solid-state architectures, high-voltage power supplies, high-voltage modulators, high-power combiners, circulators, cavities, power couplers and tuners. New ideas for high-power RF system upgrades and novel ways of RF power generation and distribution will also be discussed. CWRF2014 sessions will start on Tuesday morning and will conclude on Friday lunchtime. A visit to Elettra and FERMI will be organized during the workshop. ORGANIZING COMMITTEE (OC): Al...

  7. First lasing of the Darmstadt cw free electron laser

    CERN Document Server

    Brunken, M; Eichhorn, R; Genz, H; Gräf, H D; Loos, H; Richter, A; Schweizer, B; Stascheck, A; Wesp, T


    The Darmstadt CW FEL designed for wavelengths between 3 and 10 mu m driven by the superconducting electron accelerator S-DALINAC first lased on December 1st, 1996 and has operated thereafter successfully in the wavelength region between 6.6 and 7.8 mu m. The pulsed electron beam employed had a micro pulse length of about 2ps, with a repetition rate of 10 MHz and a peak current of 2.7 A while its energy was varied between 29.6 and 31.5 MeV. A wedged pole hybrid undulator, with 80 periods each of 0.032 m length and a magnetic field strength of 0.15-0.4T, was located in between a 15.01 m long optical cavity equipped with two high reflectivity (99.8) mirrors of 0.05 m diameter. Due to the low beam current special care with respect to the electron and optical beam properties was necessary to meet the stringent conditions in order to reach a minute small signal gain of at least a few percent resulting in amplification. Saturation was obtained after about 2000 repetitions of the photon pulse inside the cavity. The D...

  8. Photoelectric Observations of the Close Eclipsing Binary System CW Cephei

    Directory of Open Access Journals (Sweden)

    Won Yong Han


    Full Text Available Photoelectric observations of the close eclipsing binary system CW Cep, which is well known of its apsidal motion, were made on 20 nights during August and November in 1983 using two 61cm reflectors at the Sobaeksan Observing Station of Korean National Astronomical Observatory and Ilsan Observing Station of Yonsei University Observatory. Standardized new light curves in UBV system are presented with a total of 1,422 individual observations. For the corrections of regional and instrumental differences, same standard stars were observed at the two observatories. Four new times of minimum light were determined with the method of Kwee and van Woerden (1956. With all of the collected times of minima, apsidal motion of this system was checked, but the O-C values calculated by the light elements of Nha (1975 and S derhjelm (1976 did not coincide well with new times of minima. New light elements which satisfy most times of minima better, and are deduced the apsidal period derived by the new light elements turns out to be 43 years, somewhat longer than those of values previously known.

  9. Low threshold, singly-resonant CW OPO pumped by an all-fiber pump source. (United States)

    Henderson, Angus; Stafford, Ryan


    An oscillation threshold of 780mW has been demonstrated in a singly-resonant, continuous-wave optical parametric oscillator (CW SRO) using a fiber-amplified, distributed feedback (DFB) fiber laser as pump source. A linewidth of 1MHz was measured, and the idler frequency was fine-tuned by up to 130GHz by tuning the pump laser. To our knowledge, this is the first example of a single frequency CW SRO pumped by an all-fiber pump source, a reduction in threshold by a factor of three over previous 1- microm-pumped CW SROs, and a reduction by two orders of magnitude in the linewidth of CW SROs pumped by fiber pump sources.

  10. Space-Qualifiable High Reliability Frequency-Stabilized CW Laser Source Project (United States)

    National Aeronautics and Space Administration — We propose the development and space qualification of a high reliability frequency-stabilized CW laser source at 1064 nm wavelength region to satisfy the...

  11. Space-Qualifiable High Reliability Frequency-Stabilized CW Laser Source Project (United States)

    National Aeronautics and Space Administration — We propose the SBIR Phase II effort to develop and space-qualify a 1.06 micron high reliability frequency-stabilized CW laser source that fully satisfies the...

  12. Advances in electronics prompt a fresh look at continuous wave (CW) nuclear magnetic resonance (NMR)


    Newton, MI; Breeds, EA; Morris, RH


    Continuous Wave Nuclear Magnetic Resonance (CW-NMR) was a popular method for sample interrogation at the birth of magnetic resonance but has since been overlooked by most in favor of the now more popular pulsed techniques. CW-NMR requires relatively simple electronics although, for most designs, the execution is critical to the successful implementation and sensitivity of the system. For decades there have been reports in the literature from academic groups showing the potential of magnetic r...

  13. Forensic Application of FM-CW and Pulse Radar

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Koppenjan; R. S. Freeland; M. L. Miller; R. E. Yoder


    Ground-penetrating radar (GPR) technology has supplied vital assistance in criminal investigations. However, law enforcement personnel desire further developments such that the technology is rapidly deployable, and that it provides both a simple user interface and sophisticated target identification. To assist in the development of target identification algorithms, our efforts involve gathering background GPR data for the various site conditions and circumstances that often typify clandestine burials. For this study, forensic anthropologists established shallow-grave plots at The University of Tennessee Anthropological Research Facility (ARF) that are specific to GPR research. These plots contain donated human cadavers lying in various configurations and depths, surrounded by assorted construction material and backfill debris. We scanned the plots using two GPR technologies: (1) a multi-frequency synthetic-aperture FM-CW radar (200-700 MHz) (GPR-X) developed by the U.S. Department of Energy's (DOE) Special Technologies Laboratory (STL), Bechtel Nevada (Koppenjan et al., 2000), and (2) a commercial pulse radar (SIR-20) manufactured by Geophysical Survey Systems, Inc. (400 and 900 MHz)(GSSI). The sweep-frequency data show the large biological mass decomposing within the torso as encircled ''hot spots.'' The 400-MHz pulse radar exhibit major horizontal reflectors above the body, with shadow reflectors (horizontal multiples) occurring beneath the body at 60 cm depth. The 400-MHz antenna was able to discern the grave walls and folded tarp covering the lower body. Under these moist, clay-rich conditions, the 900-MHz antenna was able to penetrate slightly beyond 30 cm beneath the concrete layer. However, neither system was able to penetrate beyond a one meter depth in the moist, clay-rich soil (fine, mixed, thermic Typic Paleudalf). Example scans from each system are provided, along with a discussion of the survey protocol and general performance.

  14. An experimental study on quasi-CW fibre laser drilling of nickel superalloy (United States)

    Marimuthu, S.; Antar, M.; Dunleavey, J.; Chantzis, D.; Darlington, W.; Hayward, P.


    Laser drilling of metals and alloys is extensively used in modern manufacturing industries to produce holes of various size and shape. Currently, most laser drilling of aerospace nickel superalloys is performed using Nd:YAG laser. Over the years, many attempts were made to increase the productivity of Nd:YAG lasers drilling process, but with little success. This paper investigates the fundamental aspects of millisecond-pulsed-Quasi-CW-fibre laser drilling of aerospace nickel superalloy. The main investigation concentrates on understanding the Quasi-CW-fibre laser parameters on trepanning laser drilled hole quality and speed. The principal findings are based on controlling the recast layer, oxide layer, hole surface characteristic and fatigue performance of the laser drilled samples. The results showed that the high average power of the quasi-CW-fibre lasers can be effectively used to achieve increased trepanning drilling speed without undermining the drilling quality, which is not feasible with a free-space Nd:YAG laser. Also, low peak power and high frequency (of quasi-CW-fibre laser) can be effectively used to produce better laser drilled holes than the high peak power and low frequency, which is common with the traditional millisecond Nd:YAG drilling processes. Recast layer thickness of around 30 μm can be achieved with a trepanning speed of up to 500 mm/min with single orbit Quasi-CW fibre laser drilling of 0.75 mm hole over 5 mm thick material.

  15. Status of the development of the EU 170 GHz/1 MW/CW gyrotron

    Energy Technology Data Exchange (ETDEWEB)

    Pagonakis, Ioannis Gr., E-mail: [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Albajar, Ferran [The European Joint Undertaking for ITER and The Development of Fusion Energy, Barcelona (Spain); Alberti, Stefano [École Polytechnique Fédérale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), Lausanne (Switzerland); Avramidis, Konstantinos [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Bonicelli, Tullio [The European Joint Undertaking for ITER and The Development of Fusion Energy, Barcelona (Spain); Braunmueller, Falk [École Polytechnique Fédérale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), Lausanne (Switzerland); Bruschi, Alex [Plasma Physics Institute, National Research Council of Italy, Milano (Italy); Chelis, Ioannis [School of Electrical and Computer Engineering, National Technical University of Athens (Greece); Cismondi, Fabio [The European Joint Undertaking for ITER and The Development of Fusion Energy, Barcelona (Spain); Gantenbein, Gerd [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Hermann, Virgile [Thales Electron Devices (TED), Vélizy-Villacoublay (France); Hesch, Klaus [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Hogge, Jean-Philippe [École Polytechnique Fédérale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), Lausanne (Switzerland); Jelonnek, John; Jin, Jianbo; Illy, Stefan [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Ioannidis, Zisis C. [Faculty of Physics, National and Kapodistrian University of Athens (Greece); Kobarg, Thorsten [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); and others


    The progress in the development of the European 170 GHz, 1 MW/CW gyrotron for electron cyclotron heating & current drive (ECH&CD) on ITER is reported. A continuous wave (CW) prototype is being manufactured by Thales Electron Devices (TED), France, while a short-pulse (SP) prototype gyrotron is in parallel under manufacture at Karlsruhe Institute of Technology (KIT), with the purpose of validating the design of the CW industrial prototype components. The fabrication of most of the sub-assemblies of the SP prototype has been completed. In a first step, an existing magnetron injection gun (MIG) available at KIT was used. Despite this non-ideal configuration, the experiments provided a validation of the design, substantiated by an excellent agreement with numerical simulations. The tube, operated without a depressed collector, is able to produce more than 1 MW of output power with efficiency in excess of 30%, as expected, and compatible with the ITER requirements.

  16. Ultrahigh-resolution Cn2 profiles derived from an FM-CW radar (United States)

    Jordan, Jim R.; McLaughlin, Scott


    The U.S. Army Atmospheric Science Laboratory operates a frequency modulated-continuous wave (FM-CW) radar at White Sands Missile Range, New Mexico. This 10 cm wavelength radar has the unique capability of measuring 2 m resolution Cn2 profiles to 2 km above ground level. At this short wavelength, scattering from point targets, presumably insects, seriously contaminates the turbulence measurements. The ability of the FM-CW radar to resolve individual insects even at two km allows the insect signature to be removed from the turbulent backscatter. Radar calibration, data, and a technique for removing insect contamination are presented.

  17. A new approach to model CW CO2 laser using rate equations

    Indian Academy of Sciences (India)

    The other distinguishing feature of our model is the methodology adopted for carryingout the calculations. For instance, the CW case being a steady state, all the rate equations are thus equated to zero. In the prior works, researchers derived analytical expressions for the vibration level population densities, thatbecomes ...

  18. Design of 57.5 MHz CW RFQ structure for the Rare Isotope ...

    Indian Academy of Sciences (India)

    The principal specifications of the RFQ are: (1) formation of extremely low longitudinal emittance; (2) stable operation over a wide range of voltage for ... CW operation of an accelerating structure leads to a number of requirements for the resonators such as high shunt impedance, efficient water cooling of all parts of the ...

  19. An Airborne Millimeter-Wave FM-CW Radar for Thickness Profiling of Freshwater Ice (United States)


    Processor V silloscope rrg SCSI Card for Bernoulli Atn 80386 CPU ... .. .. ... =. : : . , . . .i : :" .::: .:::: :::. ’::::::Mo 3.5-in: :• !i~Floppy emo...34:::::: : ::::’: ,: Waterproof Aluminum ==== == === === Figure A52. FM-CW radar system implementation. 80386 DOS-based computer. Also included are an 80387 math coprocessor

  20. Independent tunability of the double-mode-locked cw dye laser.

    LENUS (Irish Health Repository)

    Bourkoff, E


    We report a new configuration that enables the double-mode-locked cw dye laser to be independently tunable. In addition, the output coupling at each of the two wavelengths can be independently specified. A series of oscillographs shows some interesting features unique to double mode locking and also shows the effects of varying the two cavity lengths with respect to each other.

  1. Broadly Tunable, Mode-Hop-Tuned cw Optical Parametric Oscillator Based on Periodically Poled Lithium Niobate (United States)

    Bisson, Scott E.; Armstrong, Karla M.; Kulp, Thomas J.; Hartings, Matthew


    We describe a broadly tunable, cw optical parametric oscillator (OPO) based on periodically poled lithium niobate. The OPO can be tuned over a broad region in the mid IR (2900 -3100 cm-1 ) covering the important C -H stretch region while a high spectral resolution ( volatile organic compounds.

  2. Broadly Turnable Pump-Resonant Diode-Pumped CW PPLN OPO

    Energy Technology Data Exchange (ETDEWEB)

    Alford, W.J.; Bowers, Mark S.; Raymond, T.D.; Seamans, J.F.


    We have observed low threshold operation of a broadly tunable (2.18-3.4 µm) pump-resonant cw periodically poled lithium niobate (PPLN) optical parametric oscillator (OPO). When pumped at 806 nm with 410 mW from a custom-built diode laser the OPO generated 20 mW of idler output at 3.3 µm.

  3. Absolute detection of metastable rare gas atoms by a cw laser photoionization method

    NARCIS (Netherlands)

    Schohl, S.; Klar, D.; Kraft, T.; Meijer, H.A.J.; Ruf, M.-W.; Schmitz, U.; Smith, S.J.; Hotop, H.


    A novel, accurate method for the absolute detection of metastable rare gas atoms is described and demonstrated. It involves a direct in situ determination of the electron emission coefficient γ for impact of the respective metastable atom on a conducting surface, γ is reliably obtained by a cw

  4. Beam-splitter mount for efficient monitoring of mode-locked and synchronously pumped CW lasers

    NARCIS (Netherlands)

    Hoek, van A.; Visser, A.J.W.G.


    Monitoring the optical pulses from mode-locked and synchronously pumped continuous wave (cw) lasers, reference beams are taken from the main beams with beam splitters. Depending on the angle with respect to the incident beam and the direction of the rotation axis of the beam splitter, light

  5. Laser and Electron Beam Processing of Semiconductors: CW Beam Processing of Ion Implanted Silicon (United States)


    1000 A) amorphous layers. Both a scanned cw atoms placed on subsitutional lattice sites for a given anneal argon laser 3 and a scanned e-beam 4...dependence ofthe product v, Nc in the prefactor densities decrease monotonically with distance from the sili- of e., ln(e.IT 2) is plotted versus 1/kT

  6. Nonlinear Effects in CW Mode-Locked Solid-State Lasers with Semiconductor Saturable Absorbers


    Kalashnikov, V. L.; Krimer, D.O.


    The influence of nonlinear properties of semiconductor saturable absorbers on ultrashort pulse generation was investigated. It was shown, that linewidth enhancement, quadratic and linear ac Stark effect contribute essentially to the mode locking in cw solid-state lasers, that can increase the pulse stability, decrease pulse duration and reduce the mode locking threshold

  7. Study of plasma formation in CW CO2 laser beam-metal surface interaction (United States)

    Azharonok, V. V.; Vasilchenko, Zh V.; Golubev, Vladimir S.; Gresev, A. N.; Zabelin, Alexandre M.; Chubrik, N. I.; Shimanovich, V. D.


    An interaction of the cw CO2 laser beam and a moving metal surface has been studied. The pulsed and thermodynamical parameters of the surface plasma were investigated by optical and spectroscopical methods. The subsonic radiation wave propagation in the erosion plasma torch has been studied.


    NARCIS (Netherlands)

    Eliel, E.R.; Hogervorst, W.; van Leeuwen, K.A.H.; Post, B.H.


    High resolution laser spectroscopy has been applied to the study of three ultraviolet transitions in Europium at λ = 294.8, 295.1 and 295.8 nm. The tunable narrowband UV has been generated by intracavity frequency doubling in a cw ring dye laser using a temperate tuned, Brewster angled ADA crystal.

  9. Heavy metal removal in an UASB-CW system treating municipal wastewater. (United States)

    de la Varga, D; Díaz, M A; Ruiz, I; Soto, M


    The objective of the present study was to investigate for the first time the long-term removal of heavy metals (HMs) in a combined UASB-CW system treating municipal wastewater. The research was carried out in a field pilot plant constituted for an up-flow anaerobic sludge bed (UASB) digester as a pretreatment, followed by a surface flow constructed wetland (CW) and finally by a subsurface flow CW. While the UASB showed (pseudo) steady state operational conditions and generated a periodical purge of sludge, CWs were characterised by the progressive accumulation and mineralisation of retained solids. This paper analyses the evolution of HM removal from the water stream over time (over a period of 4.7 year of operation) and the accumulation of HMs in UASB sludge and CW sediments at two horizons of 2.7 and 4.0 year of operation. High removal efficiencies were found for some metals in the following order: Sn > Cr > Cu > Pb > Zn > Fe (63-94%). Medium removal efficiencies were registered for Ni (49%), Hg (42%), and Ag (40%), and finally Mn and As showed negative percentage removals. Removal efficiencies of total HMs were higher in UASB and SF units and lower in the last SSF unit. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Highly efficient F-19 heteronuclear decoupling in solid-state NMR spectroscopy using supercycled refocused-CW irradiation

    DEFF Research Database (Denmark)

    Equbal, Asif; Basse, Kristoffer; Nielsen, Niels Christian


    We present heteronuclear F-19 refocused CW (rCW) decoupling pulse sequences for solid-state magic-angle- spinning NMR applications. The decoupling sequences have been designed specifically to ensure suppression of the pertinent C-13-F-19 dipolar coupling interactions while simultaneously suppress......We present heteronuclear F-19 refocused CW (rCW) decoupling pulse sequences for solid-state magic-angle- spinning NMR applications. The decoupling sequences have been designed specifically to ensure suppression of the pertinent C-13-F-19 dipolar coupling interactions while simultaneously...... of which clearly render the new rCW schemes the methods of choice for 19F decoupling in rigid, fluorinated compounds - which is further supported by a Floquet-based theoretical analysis....

  11. Antiviral Potential of a Novel Compound CW-33 against Enterovirus A71 via Inhibition of Viral 2A Protease

    Directory of Open Access Journals (Sweden)

    Ching-Ying Wang


    Full Text Available Enterovirus A71 (EV-A71 in the Picornaviridae family causes hand-foot-and-mouth disease, aseptic meningitis, severe central nervous system disease, even death. EV-A71 2A protease cleaves Type I interferon (IFN-α/β receptor 1 (IFNAR1 to block IFN-induced Jak/STAT signaling. This study investigated anti-EV-A7l activity and synergistic mechanism(s of a novel furoquinoline alkaloid compound CW-33 alone and in combination with IFN-β Anti-EV-A71 activities of CW-33 alone and in combination with IFN-β were evaluated by inhibitory assays of virus-induced apoptosis, plaque formation, and virus yield. CW-33 showed antiviral activities with an IC50 of near 200 µM in EV-A71 plaque reduction and virus yield inhibition assays. While, anti-EV-A71 activities of CW-33 combined with 100 U/mL IFN-β exhibited a synergistic potency with an IC50 of approximate 1 µM in plaque reduction and virus yield inhibition assays. Molecular docking revealed CW-33 binding to EV-A71 2A protease active sites, correlating with an inhibitory effect of CW33 on in vitro enzymatic activity of recombinant 2A protease IC50 = 53.1 µM. Western blotting demonstrated CW-33 specifically inhibiting 2A protease-mediated cleavage of IFNAR1. CW-33 also recovered Type I IFN-induced Tyk2 and STAT1 phosphorylation as well as 2',5'-OAS upregulation in EV-A71 infected cells. The results demonstrated CW-33 inhibiting viral 2A protease activity to reduce Type I IFN antagonism of EV-A71. Therefore, CW-33 combined with a low-dose of Type I IFN could be applied in developing alternative approaches to treat EV-A71 infection.

  12. Experiment for buried pipes by stepped FM-CW radar; Step shiki FM-CW radar ni yoru maisetsukan tansa jikken

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K.; Ito, M. [Kawasaki Geological Engineering, Co. Ltd., Tokyo (Japan); Tanabe, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan)


    The underground radar exploration is adopted to surveys of cavity under the road and buried pipes since the result of high resolution is obtained. However, the explorative depth of the radar is shallow, 2-3m in soil basement, and its applicable field has been limited. The continuous wave radar (FM-CW radar) was devised to get deeper explorative depth, but has been used for the geological structure survey such as the fault survey since it is lower in resolution as compared with the pulse radar. Therefore, to make use of characteristics of the continuous wave radar and enhance resolution in the shallow part, an experiment on buried pipes was conducted for the purpose of assessing and improving the FM-CW radar. In this processing, the wave form treatment used in the reflection method seismic survey was adopted for the radar survey. There are some problems, but it is effective to adopt the same algorithm to that used in the seismic survey to the radar exploration. The explorative depth was discussed from the damping rate of electromagnetic waves and dynamic range of facilities of the experimental site, and 7m was obtained. 5 figs., 1 tab.

  13. Canvas Supports and Grounds in Paintings by C.W. Eckersberg

    DEFF Research Database (Denmark)

    Filtenborg, Troels Folke; Krarup Andersen, Cecil


    The supports and grounds in 43 paintings on canvas by C.W. Eckersberg, dating from throughout his career, were investigated by visual examination, X-radiography, computer assisted automated thread counting and weave mapping, as well as by cross section analysis. The analytical data were complemen......The supports and grounds in 43 paintings on canvas by C.W. Eckersberg, dating from throughout his career, were investigated by visual examination, X-radiography, computer assisted automated thread counting and weave mapping, as well as by cross section analysis. The analytical data were...... complemented by written sources such as Eckersberg’s diaries, accounts and letters. The results show certain patterns in his practice and are discussed in relation to the varying locations and conditions in successive phases of his career and in view of contemporary paint technical treatises and circumstances...

  14. Starting dynamics of a cw passively mode-locked picosecond Ti:sapphire/DDI laser. (United States)

    Pu, N W; Shieh, J M; Lai, Y; Pan, C L


    We show that, for a cw passively mode-locked picosecond Ti:sapphire/DDI laser, the first autocorrelation trace with negligible cw background occurs at a delay time of 20 mu;s, or 1600 round trips from the first relaxationoscillation peak. The trace suggests that the pulse consists of a primary pulse as short as 4.4 ps and of small secondary pulses that form a much wider pedestal of the trace, each containing approximately 50% of the photon energy. Nearly transform-limited approximately 5-ps-wide Gaussian pulses were observed at a delay time of 40 mu;s. After 45 mu;s, the optical spectrum broadened considerably, and the time-bandwidth product increased to 4 in the steady state (after 60 micros).

  15. CW single transverse mode all-fiber Tm3+-doped silica fiber laser (United States)

    Song, E. Z.; Li, W. H.; You, L.


    The CW 25.6 W output power with a slope efficiency of 30.6% respected to the pump power from a CW single transverse mode all-fiber Tm3+-doped Silica Fiber Laser is reported. The all-fiber laser is made up by progressively splicing the pigtail fiber, matched FBG fiber and Tm fiber. The reflective FBG and Tm3+-doped fiber end Fresnel reflection build up the laser resonance cavity. Due to the multi-mode FBG as the reflective mirror, the output laser spectrum is multi-peaks at high output power, but the spectrum width is less than 2 nm at 1.94 μm. We estimate the beam quality to be M 2 = 2.39, clearly indicating nearly diffraction-limited beam propagation.

  16. Interaction of cw CO2 laser radiation with plasma near-metallic substrate surface (United States)

    Azharonok, V. V.; Astapchik, S. A.; Zabelin, Alexandre M.; Golubev, Vladimir S.; Golubev, V. S.; Grezev, A. N.; Filatov, Igor V.; Chubrik, N. I.; Shimanovich, V. D.


    Optical and spectroscopic methods were used in studying near-surface plasma that is formed under the effect CW CO2 laser of (2- 5)x106W/cm2 power density upon stainless steel in He and Ar shielding gases. The variation of plume spatial structure with time has been studied, the outflow of gas-vapor jets from the interaction area has been characterized. The spectra of plasma plume pulsations have been obtained for the frequency range Δf = 0-1 MHz. The temperature and electron concentration of plasma plume have been found under radiation effect upon the target of stainless steel. Consideration has been given to the most probable mechanisms of CW laser radiation-metal non-stationary interaction.

  17. Development of an Airborne MMW FM-CW Radar for Mapping River Ice (United States)


    installed in the33-MHz 80386 DOS- S..1.78 (Cumming 1952). based computer with an 80387 math coprocessor, a conventional 40-megabyte hard-drive and 4 mega...InterfaceI - 33M~836 CPU I x Antennas 1I. M 40 M Bernoull i LKF oppy Drive Hard Di 44 MB Disk Field-hardened Computer System Figure 5. MMWFM-CW radar system

  18. Power characteristics of CW second harmonic generation in periodically poled LiNbO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Bong Hoon; Rhee, Bum Ku [Dept. of Physics, Sogang University, Seoul (Korea, Republic of); Cha, Myoung Sik [Research Center for Dielectric and Advanced Matter Physics. Busan National University, Busan (Korea, Republic of)


    Power characteristics of CW second harmonic generation (SHG) in 0.5-mm-thick periodically poled LiNbO{sub 3} (PPLN) witha 6.5 μm domain period were investigated as a function of crystal length, and confocal parameter which was varied by using a lens of different focal length. We found there is the optimum condition of confocal parameter for SHG for a given intensity.

  19. Investigation of in-vivo skin autofluorescence lifetimes under long-term cw optical excitation

    Energy Technology Data Exchange (ETDEWEB)

    Lihachev, A; Ferulova, I; Vasiljeva, K; Spigulis, J [Institute of Atomic Physics and Spectroscopy, University of Latvia, Riga (Latvia)


    The main results obtained during the last five years in the field of laser-excited in-vivo human skin photobleaching effects are presented. The main achievements and results obtained, as well as methods and experimental devices are briefly described. In addition, the impact of long-term 405-nm cw low-power laser excitation on the skin autofluorescence lifetime is experimentally investigated. (laser biophotonics)

  20. CW laser induced crystallization of thin amorphous silicon films deposited by EBE and PECVD

    Energy Technology Data Exchange (ETDEWEB)

    Said-Bacar, Z., E-mail: [InESS (UMR 7163 CNRS-UDS), 23 rue de Loess, 67037 Strasbourg Cedex 2 (France); Prathap, P. [InESS (UMR 7163 CNRS-UDS), 23 rue de Loess, 67037 Strasbourg Cedex 2 (France); Cayron, C. [CEA, LITEN, DEHT, Minatec, 17 rue des Martyrs, 38054 Cedex 9 (France); Mermet, F. [IREPA LASER, Pole API - Parc d' Innovation, 67400 Illkirch (France); Leroy, Y.; Antoni, F.; Slaoui, A.; Fogarassy, E. [InESS (UMR 7163 CNRS-UDS), 23 rue de Loess, 67037 Strasbourg Cedex 2 (France)


    Highlights: Black-Right-Pointing-Pointer The effect of hydrogen in CW laser crystallization of hydrogenated amorphous silicon thin films has been investigated. Black-Right-Pointing-Pointer Large hydrogen content results in decohesion of the films due to hydrogen effusion. Black-Right-Pointing-Pointer Very low hydrogen content or hydrogen free amorphous silicon film are suitable for crystallization induced by CW laser. Black-Right-Pointing-Pointer Grains of size between 20 and 100 {mu}m in width and about 200 {mu}m in long in scanning direction are obtained with these latter films. - Abstract: This work presents the Continuous Wave (CW) laser crystallization of thin amorphous silicon (a-Si) films deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD) and by Electron Beam Evaporation (EBE) on low cost glass substrate. The films are characterized by Elastic Recoil Detection Analysis (ERDA) and by Fourier-Transform Infrared (FTIR) spectroscopy to evaluate the hydrogen content. Analysis shows that the PECVD films contain a high hydrogen concentration ({approx}10 at.%) while the EBE films are almost hydrogen-free. It is found that the hydrogen is in a bonding configuration with the a-Si network and in a free form, requiring a long thermal annealing for exodiffusion before the laser treatment to avoid explosive effusion. The CW laser crystallization process of the amorphous silicon films was operated in liquid phase regime. We show by Electron Backscatter Diffraction (EBSD) that polysilicon films with large grains can be obtained with EBE as well as for the PECVD amorphous silicon provided that for the latest the hydrogen content is lower than 2 at.%.

  1. A CW 4-rod RFQ for deuterons; Ein Hochleistungs-RFQ-Beschleuniger fuer Deuteronen

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, P.


    A four-rod RFQ accelerator has been built which operates in CW mode with a power consumption of 250 kW. The assembly of a high power RFQ structure requires a precise mechanical alignment and field tuning of the electrode field. The field distribution must be very flat to enable a proper operation with few losses. Adjusting of the field distribution is critical in long structures. (orig.)

  2. Evidence for orbital motion of CW Leonis from ground-based astrometry (United States)

    Sozzetti, A.; Smart, R. L.; Drimmel, R.; Giacobbe, P.; Lattanzi, M. G.


    Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations indicate that CW Leo, the closest carbon-rich asymptotic giant branch star to Sun, might have a low-mass stellar companion. We present archival ground-based astrometric measurements of CW Leo obtained within the context of the Torino Parallax Program and with >6 yr (1995-2001) of time baseline. The residuals to a single-star solution show significant curvature, and they are strongly correlated with the well-known I-band photometric variations due to stellar pulsations. We describe successfully the astrometry of CW Leo with a variability-induced motion (VIM) + acceleration model. We obtain proper motion and parallax of the centre-of-mass of the binary, the former in fair agreement with recent estimates, the latter at the near end of the range of inferred distances based on indirect methods. The VIM + acceleration model results allow us to derive a companion mass in agreement with that inferred by ALMA, they point towards a somewhat longer period than implied by ALMA, but are not compatible with much longer period estimates. These data will constitute a fundamental contribution towards the full understanding of the orbital architecture of the system when combined with Gaia astrometry, providing an ∼25 yr time baseline.

  3. Design of 57.5 MHz cw RFQ for medium energy heavy ion superconducting linac

    Directory of Open Access Journals (Sweden)

    P. N. Ostroumov


    Full Text Available The nuclear science community considers the construction of the Rare Isotope Accelerator (RIA facility as a top priority. The RIA includes a 1.4 GV superconducting linac for production of 400 kW cw heavy ion beams. The initial acceleration of heavy ions delivered from an electron cyclotron resonance ion source can be effectively performed by a 57.5 MHz 4-m long room temperature RFQ. The principal specifications of the RFQ are (i formation of extremely low longitudinal emittance, (ii stable operation over a wide range of voltage for acceleration of various ion species needed for RIA operation, and (iii simultaneous acceleration of two-charge states of uranium ions. cw operation of an accelerating structure leads to a number of requirements for the resonators such as high shunt impedance, efficient water cooling of all parts of the resonant cavity, mechanical stability together with precise alignment, reliable rf contacts, a stable operating mode, and fine tuning of the resonant frequency during operation. To satisfy these requirements a new resonant structure has been developed. This paper discusses the beam dynamics and electrodynamics design of the RFQ cavity, as well as some aspects of the mechanical design of the low-frequency cw RFQ.

  4. Non-invasive optoacoustic temperature determination during retinal cw-laser treatments (United States)

    Kandulla, Jochen; Elsner, Hanno; Sandeau, Julien; Birngruber, Reginald; Brinkmann, Ralf


    In almost all retinal laser treatments the therapeutic effect is initiated by a transient temperature increase. Due to differences in tissue properties and physiology like pigmentation and vascular blood flow an individually different temperature increase might occur with crucial effects on the therapeutic benefit of the treatment. In order to determine the individual retinal temperature increase during cw-laser irradiation in real-time we developed a non-invasive method based on optoacoustics. Simultaneously to the cw-laser irradiation (λ = 810 nm, P contact lens placed on the cornea. The experiments were performed in-vivo on rabbits. Simultaneous measurements with a miniaturized thermocouple showed a similar slope with a maximum local deviation of 0.4 °C for a temperature increase of 5.5 °C. On two rabbits measurements pre and post mortem at the same location were performed. The temperature increase after 60 s was found to raise by 12.0 % and 66.7 % post mortem, respectively. These data were used to calculate the influence of heat convection by blood circulation using a numerical model based on two absorbing layers and assuming a constant perfusion rate for the choriocapillaris and the choroid. Overall the presented optoacoustic method seems feasible for a non-invasive real-time determination of cw-laser induced retinal temperature increases and might serve as a temperature based dosimetry control during retinal laser treatments.

  5. High-power and highly reliable 638-nm band BA-LD for CW operation (United States)

    Nishida, Takehiro; Kuramoto, Kyosuke; Abe, Shinji; Kusunoki, Masatsugu; Miyashita, Motoharu; Yagi, Tetsuya


    High-power laser diodes (LDs) are strongly demanded as light sources of display applications. In multiple spatial light modulator-type projectors or liquid crystal displays, the light source LDs are operated under CW condition. The high-power 638-nm band broad-area LD for CW operation was newly developed. The LD consisted of two stripes with each width of 75 μm to reduce both an optical power density at a front facet and a threshold current. The newly improved epitaxial technology was also applied to the LD to suppress an electron overflow from an active layer. The LD showed superior output characteristics, such as output of 1.77 W at case temperature of 55 °C with wall plug efficiency (WPE) of 23%, which was improved by 40% compared with the current product. The peak WPE at 25 °C reached 40.6% under the output power of 2.37 W, CW, world highest.

  6. Stimulating ammonia oxidizing bacteria (AOB) activity drives the ammonium oxidation rate in a constructed wetland (CW). (United States)

    Su, Yu; Wang, Weidong; Wu, Di; Huang, Wei; Wang, Mengzi; Zhu, Guibing


    An integrated approach to document high ammonium oxidation rate in Guanjinggang constructed wetland (GJG-CW) was performed and the results showed that the substantial ammonium oxidation rate could be obtained by enhancing Ammonia Oxidizing Bacteria (AOB) activity rather than Ammonia Oxidizing Archaea (AOA) activity. In the plant-bed/ditch system, ditch center and plant-bed fringe were two active zones for NH4+-N removal with ammonium oxidation rate peaking at 2.98±0.04 and 2.15±0.02mgNkg-1d-1, respectively. The enhanced AOB activity were achieved by increasing water level fluctuations, extending hydraulic retention time (HRT) and stimulating substrate availability, which subsequently enhanced NH4+-N removal by 34.06% in GJG-CW. However, the high AOB activity was not correlated with high AOB abundance, but was instead mostly determined by specific AOB taxa, particularly Nitrosomonas, which dominated in the active AOB. The increased cell-specific AOA activity and high AOA diversity were also achieved using those engineering measures. Although the AOA activity decreased overall with extended HRT and increased NH4+-N contents in GJG-CW, AOA still played a major role on ammonium oxidation in plant-bed soil. The study illustrated that artificially enhancing AOB activity and certain species in anthropogenically polluted water ecosystems would be an effective strategy to improve NH4+-N removal. Copyright © 2017. Published by Elsevier B.V.

  7. Investigation of radical locations in various sesame seeds by CW EPR and 9-GHz EPR imaging. (United States)

    Nakagawa, K; Hara, H


    We investigated the location of radical in various sesame seeds using continuous-wave (CW) electron paramagnetic resonance (EPR) and 9-GHz EPR imaging. CW EPR detected persistent radicals (single line) for various sesame seeds. The EPR linewidth of black sesame seeds was narrower than that of the irradiated white sesame seeds. A very small signal was detected for the white sesame seeds. Two-dimensional (2D) imaging using a 9-GHz EPR imager showed that radical locations vary for various sesame seeds. The paramagnetic species in black sesame seeds were located on the seed coat (skin) and in the hilum region. The signal with the highest intensity was obtained from the hilum part. A very low-intensity image was observed for the white sesame seeds. In addition, the 2D imaging of the irradiated white sesame seeds showed that free radicals were located throughout the entire seed. For the first time, CW EPR and 9-GHz EPR imaging showed the exact location of radical species in various sesame seeds.

  8. EPR and 55Mn cw-ENDOR study of an antiferrogmagnetically coupled dinuclear manganese (Mn III Mn IV) complex (United States)

    Zweygart, W.; Bittl, R.; Wieghardt, K.; Lubitz, W.


    X- and Q-band EPR and 55Mn cw-ENDOR experiments are reported on a binuclear oxo-bridged dimanganese Mn III Mn IV complex. Consistent simulations of spectra from both frequency bands using one parameter set for the orthorhombic g tensor and Mn III and Mn IV hyperfine tensors are achieved. Information on the manganese hyperfine couplings is independently obtained from 55Mn cw-ENDOR spectroscopy performed on both ions.

  9. Method And System For Examining Biological Materials Using Low Power Cw Excitation Raman Spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Alfano, Robert R. (Bronx, NY); Wang, Wubao (Flushing, NY)


    A method and system for examining biological materials using low-power cw excitation Raman spectroscopy. In accordance with the teachings of the invention, a low-power continuous wave (cw) pump laser beam and a low-power cw Stokes (or anti-Stokes) probe laser beam simultaneously illuminate a biological material and traverse the biological material in collinearity. The pump beam, whose frequency is varied, is used to induce Raman emission from the biological material. The intensity of the probe beam, whose frequency is kept constant, is monitored as it leaves the biological material. When the difference between the pump and probe excitation frequencies is equal to a Raman vibrational mode frequency of the biological material, the weak probe signal becomes amplified by one or more orders of magnitude (typically up to about 10.sup.4 -10.sup.6) due to the Raman emission from the pump beam. In this manner, by monitoring the intensity of the probe beam emitted from the biological material as the pump beam is varied in frequency, one can obtain an excitation Raman spectrum for the biological material tested. The present invention may be applied to in the in vivo and/or in vitro diagnosis of diabetes, heart disease, hepatitis, cancers and other diseases by measuring the characteristic excitation Raman lines of blood glucose, cholesterol, serum glutamic oxalacetic transaminase (SGOT)/serum glutamic pyruvic tansaminase (SGPT), tissues and other corresponding Raman-active body constituents, respectively. For example, it may also be used to diagnose diseases associated with the concentration of Raman-active constituents in urine, lymph and saliva It may be used to identify cancer in the breast, cervix, uterus, ovaries and the like by measuring the fingerprint excitation Raman spectra of these tissues. It may also be used to reveal the growing of tumors or cancers by measuring the levels of nitric oxide in tissue.

  10. Laparoscopic Fluorescent Visualization of the Ureter With Intravenous IRDye800CW. (United States)

    Korb, Melissa L; Huh, Warner K; Boone, Jonathan D; Warram, Jason M; Chung, Thomas K; de Boer, Esther; Bland, Kirby I; Rosenthal, Eben L


    Ureter injury is a serious complication of laparoscopic surgery. Current strategies to identify the ureters, such as placement of a ureteral stent, carry additional risks for patients. We hypothesize that the systemically injected near-infrared (NIR) dye IRDye800CW-CA can be used to visualize ureters intraoperatively. Adult female mixed-breed pigs weighing 24 to 41 kg (n = 2 per dose) were given a 30, 60, or 120 μg/kg systemic injection of IRDye800CW-CA. Using the Food and Drug Administration-cleared Pinpoint laparoscopic NIR system, images of the ureter and bladder were captured every 10 minutes for 60 minutes after injection. To determine the biodistribution of the dye, tissues were collected for ex vivo analysis with the Pearl Impulse system. ImageJ software was used to quantify fluorescence signal and signal-to-background ratio (SBR) for the intraoperative images. The ureter was identified in all pigs at each dose, with peak intensity reached by 30 minutes and remaining elevated throughout the duration of imaging (60 minutes). The 60 μg/kg dose was determined to be optimal for differentiating ureters according to absolute fluorescence (>60 counts/pixel) and SBR (3.1). Urine fluorescence was inversely related to plasma fluorescence (R(2) = -0.82). Ex vivo imaging of kidney, ureter, bladder, and abdominal wall tissues revealed low fluorescence. Systemic administration of IRDye800CW-CA shows promise in providing ureteral identification with high specificity during laparoscopic surgery. The low dose required, rapid time to visualization, and absence of invasive ureteral instrumentation inherent to this technique may reduce complications related to pelvic surgery. Copyright © 2015 AAGL. Published by Elsevier Inc. All rights reserved.

  11. Remote wind sensing with a CW diode laser lidar beyond the coherence regime

    DEFF Research Database (Denmark)

    Hu, Qi; Rodrigo, Peter John; Pedersen, Christian


    We experimentally demonstrate for the first time (to our knowledge) a coherent CW lidar system capable of wind speed measurement at a probing distance beyond the coherence regime of the light source. A side-by-side wind measurement was conducted on the field using two lidar systems with identical...... optical designs but different laser linewidths. While one system was operating within the coherence regime, the other was measuring at least 2.4 times the coherence range. The probing distance of both lidars is 85 m and the radial wind speed correlation was measured to be r2=0.965 between the two lidars...

  12. CW seeded optical parametric amplifier providing wavelength and pulse duration tunable nearly transform limited pulses. (United States)

    Hädrich, S; Gottschall, T; Rothhardt, J; Limpert, J; Tünnermann, A


    An optical parametric amplifier that delivers nearly transform limited pulses is presented. The center wavelength of these pulses can be tuned between 993 nm and 1070 nm and, at the same time, the pulse duration is varied between 206 fs and 650 fs. At the shortest pulse duration the pulse energy was increased up to 7.2 microJ at 50 kHz repetition rate. Variation of the wavelength is achieved by applying a tunable cw seed while the pulse duration can be varied via altering the pump pulse duration. This scheme offers superior flexibility and scaling possibilities.

  13. Fourier-Bessel Field Calculation and Tuning of a CW Annular Array

    DEFF Research Database (Denmark)

    Fox, Paul D.; Cheng, Jiqi; Lu, Jian-yu


    field by linking the quantized surface pressure profile to a set of limited diffraction Bessel beams propagating into the medium. In the limit, these become a known set of nondiffracting Bessel beams satisfying the lossless linear wave equation, which allow us to derive a linear matrix formulation......A 1-D Fourier-Bessel series method for computing and tuning the linear lossless field of flat continuous wave (CW) annular arrays is given and discussed with both numerical simulation and experimental verification. The technique provides a new method for modelling and manipulating the propagated...

  14. Broad-band chopper for a CW proton linac at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Gianfelice-Wendt, E.; Lebedev, V.A.; Solyak, N.; Nagaitsev, S.; Sun, D.; /Fermilab


    The future Fermilab program in the high energy physics is based on a new facility called the Project X [1] to be built in the following decade. It is based on a 3 MW CW linear accelerator delivering the 3 GeV 1 mA H{sup -} beam to a few experiments simultaneously. Small fraction of this beam will be redirected for further acceleration to 8 GeV to be injected to the Recycler/Main Injector for a usage in a neutrino program and other synchrotron based high energy experiments. Requirements and technical limitations to the bunch-by-bunch chopper for the Fermilab Project X are discussed.

  15. Feasibility and conceptual design of a C.W. positron source at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Golge, Serkan [Old Dominion Univ., Norfolk, VA (United States)


    A feasibility study of a CW positron source for the 12 GeV upgrade at Jefferson Lab (JLAB) is provided. The proposed ≥ 100 nA Continuous Wave (CW) positron source at JLAB has several unique and challenging characteristics: high current incident electron beam at 126 MeV with a high beam power (up to a MW); CW e- beam and CW e+ production. The multiple scattering is a dominant process when creating e+ in a target, which results a large phase space area of the emitted positrons. An admittance study was done at CEBAF to find the maximum phase space area, which is tolerated in the machine. The measured geometrical transverse admittance (A) were Ax =10 and Ay = 5 mm∙mrad at the injector. Energy spread measurement was also done at the ARC1. The fractional spread limit in the ARC1 was measured as δ = 3×10-3 at 653 MeV. By using the optimized results and the CEBAF parameters, three positron injector configurations are proposed; Combined Function Magnet, Two-Dipole and Microtron Dipole configurations. With the assumptions made, by using 126 MeV Ⓧ10 mA e- beam impinging on a 2 mm W target with a 100 μm spot size, we can get up to 3 μA useful e+ current at the North Linac connection. One of the biggest challenges is the target design, which the deposited power is about 60 kW. ILC designs project power deposition up to 13 kW, which would allow the creation of a e+ beam of up to 650 nA otherwise. The results of analytic and monte carlo simulations of the positron production, capture and acceleration are presented. For the target design, a review is presented of solutions for the high power production target. Portions of this dissertation work have been published in two conference proceedings.

  16. Use of Multipass Recirculation and Energy Recovery In CW SRF X-FEL Driver Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, David; Akers, Walt; Benson, Stephen V.; Biallas, George; Blackburn, Keith; Boyce, James; Bullard, Donald; Coleman, James; Dickover, Cody; Ellingsworth, Forrest; Evtushenko, Pavel; Fisk, Sally; Gould, Christopher; Gubeli, Joseph; Hannon, Fay; Hardy, David; Hernandez-Garcia, Carlos; Jordan, Kevin; Klopf, John; Kortze, J.; Legg, Robert; Li, Rui; Marchlik, Matthew; Moore, Steven W.; Neil, George; Powers, Thomas; Sexton, Daniel; Shin, Ilkyoung; Shinn, Michelle D.; Tennant, Christopher; Terzic, Balsa; Walker, Richard; Williams, Gwyn P.; Wilson, G.; Zhang, Shukui


    We discuss the use of multipass recirculation and energy recovery in CW SRF drivers for short wavelength FELs. Benefits include cost management (through reduced system footprint, required RF and SRF hardware, and associated infrastructure - including high power beam dumps and cryogenic systems), ease in radiation control (low drive beam exhaust energy), ability to accelerate and deliver multiple beams of differing energy to multiple FELs, and opportunity for seamless integration of multistage bunch length compression into the longitudinal matching scenario. Issues include all those associated with ERLs compounded by the challenge of generating and preserving the CW electron drive beam brightness required by short wavelength FELs. We thus consider the impact of space charge, BBU and other environmental wakes and impedances, ISR and CSR, potential for microbunching, intra-beam and beam-residual gas scattering, ion effects, RF transients, and halo, as well as the effect of traditional design, fabrication, installation and operational errors (lattice aberrations, alignment, powering, field quality). Context for the discussion is provided by JLAMP, the proposed VUV/X-ray upgrade to the existing Jefferson Lab FEL.

  17. Homogeneity and EPR metrics for assessment of regular grids used in CW EPR powder simulations (United States)

    Crăciun, Cora


    CW EPR powder spectra may be approximated numerically using a spherical grid and a Voronoi tessellation-based cubature. For a given spin system, the quality of simulated EPR spectra depends on the grid type, size, and orientation in the molecular frame. In previous work, the grids used in CW EPR powder simulations have been compared mainly from geometric perspective. However, some grids with similar homogeneity degree generate different quality simulated spectra. This paper evaluates the grids from EPR perspective, by defining two metrics depending on the spin system characteristics and the grid Voronoi tessellation. The first metric determines if the grid points are EPR-centred in their Voronoi cells, based on the resonance magnetic field variations inside these cells. The second metric verifies if the adjacent Voronoi cells of the tessellation are EPR-overlapping, by computing the common range of their resonance magnetic field intervals. Beside a series of well known regular grids, the paper investigates a modified ZCW grid and a Fibonacci spherical code, which are new in the context of EPR simulations. For the investigated grids, the EPR metrics bring more information than the homogeneity quantities and are better related to the grids’ EPR behaviour, for different spin system symmetries. The metrics’ efficiency and limits are finally verified for grids generated from the initial ones, by using the original or magnetic field-constraint variants of the Spherical Centroidal Voronoi Tessellation method.

  18. Toward an integrated computational approach to CW-ESR spectra of free radicals. (United States)

    Barone, Vincenzo; Polimeno, Antonino


    Interpretation of structural properties and dynamic behaviour of molecules in solution is of fundamental importance to understand their stability, chemical reactivity and catalytic action. Information can be gained, in principle, by a variety of spectroscopic techniques, magnetic as well as optical. In particular, continuous wave electron spin resonance (CW-ESR) measurements are highly informative. However, the wealth of structural and dynamic information which can be extracted from ESR spectroscopy is, at present, limited by the necessity of employing computationally efficient models, which are increasingly complex as they need to take into account diverse relaxation processes affecting the spectrum. In this paper, we address the basic theoretical tools needed to predict, essentially ab initio, CW-ESR spectra observables according to the stochastic Liouville equation (SLE) approach, combined with quantum mechanical and hybrid methods for the accurate and efficient computation of structural, spectroscopic and magnetic properties of molecular systems. We shall discuss, on one hand, the quantum mechanical calculation of magnetic observables, via density functional theory (DFT), time-dependent DFT (TD-DFT) and application of the polarizable continuum model (PCM) for the description of environmental effects, including anisotropic environments and systems where different regions are characterized by different dielectric constants. One the other hand, the explicit evaluation of dynamical effects will be discussed based on the numerically exact treatment of the SLE in the presence of several relaxation processes, which has been proven to be a challenging task.

  19. Hardness variation of welded boron steel using continuous wave (CW) and pulse wave (PW) mode of fiber laser (United States)

    Yaakob, K. I.; Ishak, M.; Idris, S. R. A.; Aiman, M. H.; Khalil, N. Z.


    Recent car manufacturer requirement in lightweight and optimum safety lead to utilization of boron steel with tailor welded blank approach. Laser welding process in tailor welded blank (TWB) production can be applied in continuous wave (CW) of pulse wave (PW) which produce different thermal experience in welded area. Instead of microstructure identification, hardness properties also can determine the behavior of weld area. In this paper, hardness variation of welded boron steel using PW and CW mode is investigated. Welding process is conducted using similar average power for both welding mode. Hardness variation across weld area is observed. The result shows similar hardness pattern across weld area for both welding mode. Hardness degradation at fusion zone (FZ) is due to ferrite formation existence from high heat input applied. With additional slower cooling rate for CW mode, the hardness degradation is become obvious. The normal variation of hardness behavior with PW mode might lead to good strength.

  20. Experimental evaluation of the cw lasing threshold for a Ce:LiCaAlF6 laser. (United States)

    Alderighi, D; Toci, G; Vannini, M; Parisi, D; Tonelli, M


    We present an experimental technique that allows the direct measurement of the continuous wave (cw) lasing threshold and the slope efficiency of a Ce:LiCaAlF6 (Ce:LiCAF) laser source by means of time-resolved measurement in the pulsed regime. We used a long-pulse-duration source to pump a tunable laser and a high-efficiency nondispersive laser in a quasi-stationary lasing regime. We compare the experimental results with earlier theoretical evaluations, and we demonstrate the feasibility of a cw Ce:LiCAF laser. Under the conditions discussed here, our technique can be applied to all the active media that achieved pulsed laser emission to investigate their potential as cw laser active media.

  1. First Light Curve Analyses of Binary Systems AO Aqr, CW Aqr and ASAS 012206-4924.7


    Ulas, Burak; Ulusoy, Ceren


    Using the data from the public database of the All Sky Automated Survey ({\\tt ASAS}) we performed the very first light curve analyses of the three eclipsing binary systems \\astrobj{AO~Aqr}, \\astrobj{CW~Aqr} and \\astrobj{ASAS~012206-4924.7}. The physical parameters of the systems were determined by the {\\tt PHOEBE} software. From an analysis of the ASAS data it was concluded that AO~Aqr was found to be a contact binary system while CW~Aqr and ASAS~012206-4924.7 were found to be near--contact a...

  2. Variable-wavelength second harmonic generation of CW Yb-fibre laser in partially coupled enhancement cavity. (United States)

    Khripunov, Sergey; Radnatarov, Daba; Kobtsev, Sergey; Skorkin, Aleksey


    This work for the first time proposes and studies a method of frequency doubling of CW non-single-frequency fibre lasers with a high-Q resonator partially coupled to the fibre laser cavity. The proposed new approach resulted in the following parameters: laser's maximal output power 880 mW at 536 nm when pumped with 6.2 W at 976 nm, wavelength tuneability range 521-545 nm with the output power at the extreme ends of this range 420 and 220 mW correspondingly. The proposed configuration allows efficient non-linear transformation of both CW and pulsed radiation in a partially coupled enhancement cavity.

  3. Controlling software development of CW terahertz target scattering properties measurements based on LabVIEW (United States)

    Fan, Chang-Kun; Li, Qi; Zhou, Yi; Zhao, Yong-Peng; Chen, De-Ying


    With the development of terahertz technology and increasing studies on terahertz target scattering properties, research on terahertz target scattering properties measurements attracts more and more attention. In this paper, to solve problems in the detection process, we design a controlling software for Continuous-Wave (CW) terahertz target scattering properties measurements. The software is designed and programmed based on LabVIEW. The software controls the whole system, involving the switch between the target and the calibration target, the rotation of target, collection, display and storage of the initial data and display, storage of the data after the calibration process. The experimental results show that the software can accomplish the expected requirement, enhance the speed of scattering properties measurements and reduce operation errors.

  4. He-Ne and cw CO2 laser long-path systems for gas detection. (United States)

    Grant, W B


    This paper describes the design and testing of a laboratory prototype dual He-Ne laser system for the detection of methane leaks from underground pipelines and solid-waste landfill sites using differential absorption of radiation backscattered from topographic targets. A laboratory-prototype dual cw carbon dioxide laser system also using topographic backscatter is discussed, and measurement results for methanol are given. With both systems, it was observed that the time-varying differential absorption signal was useful in indicating the presence of a gas coming from a nearby source. Limitations to measurement sensitivity, especially the role of speckle and atmospheric turbulence, are described. The speckle results for hard targets are contrasted with those from atmospheric aerosols. The Appendix gives appropriate laser lines and values of absorption coefficients for the hydrazine fuel gases.

  5. Fiber-laser-pumped CW OPO for red, green, blue laser generation. (United States)

    Lin, S T; Lin, Y Y; Tu, R Y; Wang, T D; Huang, Y C


    We report a CW, watt-level, red, green, and blue (RGB) laser pumped by an economical multimode (1-nm linewidth) Yb-fiber laser at 1.064 mum. A singly resonant optical parametric oscillator at 1.56 mum has two intracavity sum-frequency generators for red and blue laser generation. An extracavity second harmonic generator converts the residual pump power into green laser radiation. At 25-W pump power, the laser generated 3.9, 0.456, and 0.49 W at 633, 532, and 450 nm, respectively. The multimode pump laser offers a large temperature bandwidth for operating the RGB OPO without the need of a precision crystal temperature stabilizer.

  6. Optical trapping assembling of clusters and nanoparticles in solution by CW and femtosecond lasers

    KAUST Repository

    Masuhara, Hiroshi


    Laser trapping of molecular systems in solution is classified into three cases: JUST TRAPPING, EXTENDED TRAPPING, and NUCLEATION and GROWTH. The nucleation in amino acid solutions depends on where the 1064-nm CW trapping laser is focused, and crystallization and liquid–liquid phase separation are induced by laser trapping at the solution/air surface and the solution/glass interface, respectively. Laser trapping crystallization is achieved even in unsaturated solution, on which unique controls of crystallization are made possible. Crystal size is arbitrarily controlled by tuning laser power for a plate-like anhydrous crystal of l-phenylalanine. The α- or γ-crystal polymorph of glycine is selectively prepared by changing laser power and polarization. Further efficient trapping of nanoparticles and their following ejection induced by femtosecond laser pulses are introduced as unique trapping phenomena and finally future perspective is presented.

  7. Design of spherical electron gun for ultra high frequency, CW power inductive output tube

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Meenu, E-mail:; Joshi, L. M., E-mail: [Microwave Tubes Division, CSIR-Central Electronics Engineering Research Institute (CEERI), Pilani, Rajasthan (India); Academy of Scientific and Innovative Research (AcSIR), New Delhi (India)


    Inductive Output Tube (IOT) is an amplifier that usually operates in UHF range. It is an electron tube whose basic structure is similar to conventional vacuum devices. This device is widely used in broadcast applications but is now being explored for scientific applications also specifically, particle accelerators and fusion plasma heating purposes. The paper describes the design approach of a spherical gridded electron gun of a 500 MHz, 100 kW CW power IOT. The electron gun structure has been simulated and optimized for operating voltage and current of 40kV and 3.5 A respectively. The electromagnetic analysis of this spherical electron gun has been carried out in CST and TRAK codes.

  8. A 350 MHz, 200 kW CW, Multiple Beam Inductive Output Tube - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    R.Lawrece Ives; George Collins; David Marsden Michael Read; Edward Eisen; Takuchi Kamura, Philipp Borchard


    This program developed a 200 kW CW, 350 MHz, multiple beam inductive output tube (MBIOT) for driving accelerator cavities. The MBIOT operates at 30 kV with a gain of 23 dB. The estimated efficiency is 70%. The device uses seven electron beams, each transmitting 1.4 A of current. The tube is approximately six feet long and weighs approximately 400 lbs. The prototype device will be evaluated as a potential RF source for the Advanced Photon Source at Argonne National Laboratory (ANL). Because of issues related to delivery of the electron guns, it was not possible to complete assembly and test of the MBIOT during the Phase II program. The device is being completed with support from Calabazas Creek Research, Inc., Communications & Power Industries, LLC. and the Naval Surface Weapons Center (NSWC) in Dahlgren, VA. The MBIOT will be initially tested at NSWC before delivery to ANL. The testing at NSWC is scheduled for February 2013.

  9. Operation of a sub-terahertz CW gyrotron with an extremely low voltage (United States)

    Bratman, V. L.; Fedotov, A. E.; Fokin, A. P.; Glyavin, M. Yu.; Manuilov, V. N.; Osharin, I. V.


    Decreasing the operating voltage for medium-power sub-terahertz gyrotrons aimed at industrial and scientific applications is highly attractive, since it allows size and cost reduction of the tubes and power supply units. In this paper, we examine such an opportunity both numerically and experimentally for the fundamental cyclotron resonance operation of an existing gyrotron initially designed for operation at the second cyclotron harmonic with a relatively high voltage. Simulations predict that output power higher than 10 W can be produced at the fundamental harmonic at voltages less than 2 kV. To form a low-voltage helical electron beam with a sufficiently large pitch-factor, a positive voltage was applied to the first anode of the gyrotron three-electrode magnetron-injection gun with a negative voltage at the cathode. CW gyrotron operation at voltages down to 1.5 kV has been demonstrated at a frequency about of 256 GHz.

  10. Surface hardening using cw CO2 laser: laser heat treatment, modelation, and experimental work (United States)

    Muniz, German; Alum, Jorge


    In the present work are given the results of the application of laser metal surface hardening techniques using a cw carbon dioxide laser as an energy source on steel 65 G. The laser heat treatment results are presented theoretically and experimentally. Continuous wave carbon dioxide laser of 0.6, 0.3, and 0.4 kW were used. A physical model for the descriptions of the thermophysical laser metal interactions process is given and a numerical algorithm is used to solve this problem by means of the LHT code. The results are compared with the corresponding experimental ones and a very good agreement is observed. The LHT code is able to do predictions of transformation hardening by laser heating. These results will be completed with other ones concerning laser alloying and cladding presented in a second paper.

  11. Design and testing of a 750MHz CW-EPR digital console for small animal imaging. (United States)

    Sato-Akaba, Hideo; Emoto, Miho C; Hirata, Hiroshi; Fujii, Hirotada G


    This paper describes the development of a digital console for three-dimensional (3D) continuous wave electron paramagnetic resonance (CW-EPR) imaging of a small animal to improve the signal-to-noise ratio and lower the cost of the EPR imaging system. A RF generation board, an RF acquisition board and a digital signal processing (DSP) & control board were built for the digital EPR detection. Direct sampling of the reflected RF signal from a resonator (approximately 750MHz), which contains the EPR signal, was carried out using a band-pass subsampling method. A direct automatic control system to reduce the reflection from the resonator was proposed and implemented in the digital EPR detection scheme. All DSP tasks were carried out in field programmable gate array ICs. In vivo 3D imaging of nitroxyl radicals in a mouse's head was successfully performed. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Revealing statistical properties of quasi-CW fibre lasers in bandwidth-limited measurements. (United States)

    Gorbunov, O A; Sugavanam, S; Churkin, D V


    We introduce a general technique how to reveal in experiments of limited electrical bandwidth which is lower than the optical bandwidth of the optical signal under study, whether the statistical properties of the light source obey Gaussian distribution or mode correlations do exist. To do that one needs to perform measurements by decreasing the measurement bandwidth. We develop a simple model of bandwidth-limited measurements and predict universal laws how intensity probability density function and intensity auto-correlation function of ideal completely stochastic source of Gaussian statistics depend on limited measurement bandwidth and measurement noise level. Results of experimental investigation are in good agreement with model predictions. In particular, we reveal partial mode correlations in the radiation of quasi-CW Raman fibre laser.

  13. Influence of geomagnetic field for continuous wave (CW) laser excited sodium guide stars backward fluorescence intensity (United States)

    Zhang, Shao-peng; Wang, Hong-yan; Hua, Wei-hong; Ning, Yu; Xu, Xiao-jun


    Recent years, benefited from their greater coverage and smaller focus anisoplanatism, sodium laser guide stars are becoming more attractive in providing artificial beacons for adaptive optical (AO) system in large ground telescopes compared to Rayleigh guide stars. And it had been found that the Sodium laser guide stars backward fluorescence intensity is closely related with the local magnetic field intensity and direction. In this paper, we make use of the World Magnetic Model (WMM) 2010 and by considering the geographical differences in Beijing, Nanjing and Kunming we investigate the effects of the light intensity, line-width, polarization of the CW laser and re-pumping conditions on the photon return flux by numerically solving the Rochester et al. Bloch model. So in theory we can get better Sodium guide star in Beijing. In conclusion, according to the simulation results, we can acquire much bright of Sodium guide stars by optimize the parameter of the launched 589 nm laser.

  14. Regional and Global Atmospheric CO2 Measurements Using 1.57 Micron IM-CW Lidar (United States)

    Lin, Bing; Obland, Michael; Nehrir, Amin; Browell, Edward; Harrison, F. Wallace; Dobler, Jeremy; Campbell, Joel; Kooi, Susan; Meadows, Byron; Fan, Tai-Fang; hide


    Atmospheric CO2 is a critical forcing for the Earth's climate, and knowledge of its distribution and variations influences predictions of the Earth's future climate. Accurate observations of atmospheric CO2 are also crucial to improving our understanding of CO2 sources, sinks and transports. To meet these science needs, NASA is developing technologies for the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) space mission, which is aimed at global CO2 observations. Meanwhile an airborne investigation of atmospheric CO2 distributions as part of the NASA Suborbital Atmospheric Carbon and Transport â€" America (ACT-America) mission will be conducted with lidar and in situ instrumentation over the central and eastern United States during all four seasons and under a wide range of meteorological conditions. In preparing for the ASCENDS mission, NASA Langley Research Center and Exelis Inc./Harris Corp. have jointly developed and demonstrated the capability of atmospheric CO2 column measurements with an intensity-modulated continuous-wave (IM-CW) lidar. Since 2005, a total of 14 flight campaigns have been conducted. A measurement precision of approx.0.3 ppmv for a 10-s average over desert and vegetated surfaces has been achieved, and the lidar CO2 measurements also agree well with in-situ observations. Significant atmospheric CO2 variations on various spatiotemporal scales have been observed during these campaigns. For example, around 10-ppm CO2 changes were found within free troposphere in a region of about 200A-300 sq km over Iowa during a summer 2014 flight. Results from recent flight campaigns are presented in this paper. The ability to achieve the science objectives of the ASCENDS mission with an IM-CW lidar is also discussed in this paper, along with the plans for the ACT-America aircraft investigation that begins in the winter of 2016.

  15. Advancing IM-CW Lidar Modulation Techniques for ASCENDS CO2 Column Measurements from Space (United States)

    Campbell, J. F.; Lin, B.; Nehrir, A. R.; Harrison, F. W.; Chen, S.; Obland, M. D.


    Global atmospheric carbon dioxide (CO2) measurements through the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) decadal survey recommended space mission are critical for improving our understanding of CO2 sources and sinks. IM-CW (Intensity Modulated Continuous Wave) lidar techniques are investigated as a means of facilitating CO2 measurements from space to meet the ASCENDS science requirements. In previous laboratory and flight experiments we have successfully used linear swept frequency modulation to discriminate surface lidar returns from intermediate aerosol and cloud contamination. Furthermore, high accuracy and precision ranging to the surface as well as to the top of intermediate clouds, which is a requirement for the inversion of the CO2 column mixing ratio from the instrument optical depth measurements, has been demonstrated with the linear swept frequency modulation technique. We are concurrently investigating advanced techniques to help improve the auto-correlation properties of the transmitted waveform implemented through physical hardware to make cloud rejection more robust in special restricted scenarios. Several different modulation techniques are compared including orthogonal linear swept, orthogonal non-linear swept, time shifted PN, sine wave modulated PN, and sine wave pulsed PN. Different PN code techniques are presented that are appropriate for different types of lidar hardware, including our current ASCENDS IM-CW concept space hardware. These techniques have excellent auto-correlation properties without sidelobes while possessing a finite bandwidth (by way of a new cyclic digital filter), which will reduce bias error in the presence of multiple scatterers. Our analyses show that the studied modulation techniques can increase the accuracy of CO2 column measurements from space.

  16. HLA-Cw Allele Frequency in Definite Meniere’s Disease Compared to Probable Meniere’s Disease and Healthy Controls in an Iranian Sample

    Directory of Open Access Journals (Sweden)

    Sasan Dabiri


    Full Text Available Introduction Several lines of evidence support the contribution of autoimmune mechanisms in the pathogenesis of Meniere’s disease. The aim of this study was determining the association between HLA-Cw Alleles in patients with definite Meniere’s disease and patients with probable Meniere’s disease and a control group.  Materials and Methods: HLA-Cw genotyping was performed in 23 patients with definite Meniere’s disease, 24 with probable Meniere’s disease, and 91 healthy normal subjects, using sequence specific primers polymerase chain reaction technique. The statistical analysis was performed using stata 8 software.  Results: There was a significant association between HLA-Cw*04 and HLA-Cw*16 in both definite and probable Meniere’s disease compared to normal healthy controls. We observed a significant difference in HLA-Cw*12 frequencies between patients with definite Meniere’s disease compared to patients with probable Meniere’s disease (P=0.04. The frequency of HLA-Cw*18 is significantly higher in healthy controls (P=0.002.  Conclusion: Our findings support the rule of HLA-Cw Alleles in both definite and probable Meniere’s disease. In addition, differences in HLA-Cw*12 frequency in definite and probable Meniere’s disease in our study’s population might indicate distinct immune and inflammatory mechanisms involved in each condition.

  17. Controllable generation and manipulation of micro-bubbles in water with absorptive colloid particles by CW laser radiation

    DEFF Research Database (Denmark)

    Angelsky, O. V.; Bekshaev, A. Ya.; Maksimyak, P. P.


    Micrometer-sized vapor-gas bubbles are formed due to local heating of a water suspension containing absorptive pigment particles of 100 nm diameter. The heating is performed by CW near-infrared (980 nm) laser radiation with controllable power, focused into a 100 mu m spot within a 2 mm suspension...

  18. [Effect of cw laser YAG: Nd laser beam on the wall of the urinary bladder taken from cadavers]. (United States)

    Kuzaka, B; Mindak, M; Pykało, R

    The results of irradiation of the urinary bladder wall with cw YAG:Nd laser beam are presented. The use of irradiation times ranging from 02, and 0.8 second destroyed irradiated tissues up to a half of the muscular laser.

  19. Intracavity doubling of CW Ti:sapphire laser to 392.5 nm using BiBO-crystal

    DEFF Research Database (Denmark)

    Mortensen, Jesper Liltorp; Thorhauge, Morten; Tidemand-Lichtenberg, Peter


    In this work we present results obtained for intra-cavity frequency-doubling of a 785 nm CW Ti:sapphire laser utilising BiBO as the non-linear crystal. Intracavity doubling offers several advantages compared to extra-cavity doubling, such as no need to couple to an external resonance cavity, and ...

  20. CW operation of high-power blue laser diodes with polished facets on semi-polar ( 20 2 ¯ 1 ¯ ) GaN substrates

    KAUST Repository

    Pourhashemi, A.


    Continuous wave (CW) operation of high-power blue laser diodes (LDs) with polished facets on semi-polar (202̅1̅) gallium nitride (GaN) substrates is demonstrated. Ridge waveguide LDs were fabricated using indium GaN waveguiding layers and GaN cladding layers. At a lasing wavelength of 452 nm, the peak two-facet CW output power from an LD with uncoated facets was 1.71 W at a current of 3 A, corresponding to an optical power density of 32.04 MW/cm2 on each facet. The dependence of output power on current did not change with repeated CW measurements, indicating that the polished facets did not degrade under high-power CW operation. These results show that polished facets are a viable alternative to cleaved or etched facets for high-power CW semi-polar LDs.

  1. Integrating in silico and in vitro analysis of peptide binding affinity to HLA-Cw*0102: a bioinformatic approach to the prediction of new epitopes.

    Directory of Open Access Journals (Sweden)

    Valerie A Walshe


    Full Text Available Predictive models of peptide-Major Histocompatibility Complex (MHC binding affinity are important components of modern computational immunovaccinology. Here, we describe the development and deployment of a reliable peptide-binding prediction method for a previously poorly-characterized human MHC class I allele, HLA-Cw*0102.Using an in-house, flow cytometry-based MHC stabilization assay we generated novel peptide binding data, from which we derived a precise two-dimensional quantitative structure-activity relationship (2D-QSAR binding model. This allowed us to explore the peptide specificity of HLA-Cw*0102 molecule in detail. We used this model to design peptides optimized for HLA-Cw*0102-binding. Experimental analysis showed these peptides to have high binding affinities for the HLA-Cw*0102 molecule. As a functional validation of our approach, we also predicted HLA-Cw*0102-binding peptides within the HIV-1 genome, identifying a set of potent binding peptides. The most affine of these binding peptides was subsequently determined to be an epitope recognized in a subset of HLA-Cw*0102-positive individuals chronically infected with HIV-1.A functionally-validated in silico-in vitro approach to the reliable and efficient prediction of peptide binding to a previously uncharacterized human MHC allele HLA-Cw*0102 was developed. This technique is generally applicable to all T cell epitope identification problems in immunology and vaccinology.

  2. A computer control system for the PNC high power cw electron linac. Concept and hardware

    Energy Technology Data Exchange (ETDEWEB)

    Emoto, T.; Hirano, K.; Takei, Hayanori; Nomura, Masahiro; Tani, S. [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center; Kato, Y.; Ishikawa, Y.


    Design and construction of a high power cw (Continuous Wave) electron linac for studying feasibility of nuclear waste transmutation was started in 1989 at PNC. The PNC accelerator (10 MeV, 20 mA average current, 4 ms pulse width, 50 Hz repetition) is dedicated machine for development of the high current acceleration technology in future need. The computer control system is responsible for accelerator control and supporting the experiment for high power operation. The feature of the system is the measurements of accelerator status simultaneously and modularity of software and hardware for easily implemented for modification or expansion. The high speed network (SCRAM Net {approx} 15 MB/s), Ethernet, and front end processors (Digital Signal Processor) were employed for the high speed data taking and control. The system was designed to be standard modules and software implemented man machine interface. Due to graphical-user-interface and object-oriented-programming, the software development environment is effortless programming and maintenance. (author)

  3. A 10-watt CW photodissociation laser with IODO perfluoro-tert-butane (United States)

    Tabibi, Bagher; Venable, Demetrius D.


    NASA has been investigating the feasibility of direct solar-pumped laser systems for power beaming in space. Among the various gas, liquid, and solid laser systems being proposed as candidates for solar-pumped lasers, the iodine photodissociation gas laser has demonstrated its potential for space application. Of immediate attention is the determination of system requirements and the choice of lasants to improve the system efficiency. The development of an efficient iodine laser depends on the availability of a suitable iodide which has favorable laser kinetics, chemically reversibility, and solar energy utilization. Among the various alkyliodide lasants comparatively tested in a long-pulse system, perfluoro- tert-butyl iodide, T-C4F9I, was found to be the best. However, the operating conditions for the laser medium in a continuously pumped and continuous-flow iodine laser differ considerably from those in the pulsed regime. The results of the continuous wave (CW)) laser performance from t-C4F9I are reported. Perfluoro- n-propyl iodide, n-C3F7I is used for comparison because of its universal use in photodissociation iodine lasers.

  4. Efficient Low-Voltage Operation of a CW Gyrotron Oscillator at 233 GHz. (United States)

    Hornstein, Melissa K; Bajaj, Vikram S; Griffin, Robert G; Temkin, Richard J


    The gyrotron oscillator is a source of high average power millimeter-wave through terahertz radiation. In this paper, we report low beam power and high-efficiency operation of a tunable gyrotron oscillator at 233 GHz. The low-voltage operating mode provides a path to further miniaturization of the gyrotron through reduction in the size of the electron gun, power supply, collector, and cooling system, which will benefit industrial and scientific applications requiring portability. Detailed studies of low-voltage operation in the TE(2) (,) (3) (,) (1) mode reveal that the mode can be excited with less than 7 W of beam power at 3.5 kV. During CW operation with 3.5-kV beam voltage and 50-mA beam current, the gyrotron generates 12 W of RF power at 233.2 GHz. The EGUN electron optics code describes the low-voltage operation of the electron gun. Using gun-operating parameters derived from EGUN simulations, we show that a linear theory adequately predicts the low experimental starting currents.

  5. Functional role of the additional domains in inulosucrase (IslA from Leuconostoc citreum CW28

    Directory of Open Access Journals (Sweden)

    Munguia Agustin


    Full Text Available Abstract Background Inulosucrase (IslA from Leuconostoc citreum CW28 belongs to a new subfamily of multidomain fructosyltransferases (FTFs, containing additional domains from glucosyltransferases. It is not known what the function of the additional domains in this subfamily is. Results Through construction of truncated versions we demonstrate that the acquired regions are involved in anchoring IslA to the cell wall; they also confer stability to the enzyme, generating a larger structure that affects its kinetic properties and reaction specificity, particularly the hydrolysis and transglycosylase ratio. The accessibility of larger molecules such as EDTA to the catalytic domain (where a Ca2+ binding site is located is also affected as demonstrated by the requirement of 100 times higher EDTA concentrations to inactivate IslA with respect to the smallest truncated form. Conclusion The C-terminal domain may have been acquired to anchor inulosucrase to the cell surface. Furthermore, the acquired domains in IslA interact with the catalytic core resulting in a new conformation that renders the enzyme more stable and switch the specificity from a hydrolytic to a transglycosylase mechanism. Based on these results, chimeric constructions may become a strategy to stabilize and modulate biocatalysts based on FTF activity.

  6. A CW radiofrequency ion source for production of negative hydrogen ion beams for cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Kalvas, T.; Tarvainen, O.; Komppula, J.; Koivisto, H.; Tuunanen, J. [University of Jyväskylä, Department of Physics (Finland); Potkins, D.; Stewart, T.; Dehnel, M. P. [D-Pace, Inc., Nelson, B.C. Canada (Canada)


    A CW 13.56 MHz radiofrequency-driven ion source RADIS for production of H{sup −} and D{sup −} beams is under development for replacing the filament-driven ion source of the MCC30/15 cyclotron. The RF ion source has a 16-pole multicusp plasma chamber, an electromagnet-based magnetic filter and an external planar spiral RF antenna behind an AlN window. The extraction is a 5-electrode system with an adjustable puller electrode voltage for optimizing the beam formation, a water-cooled electron dump electrode and an accelerating einzel lens. At 2650 W of RF power, the source produces 1 mA of H{sup −} (2.6 mA/cm{sup 2}), which is the intensity needed at injection for production of 200 µA H{sup +} with the filament-driven ion source. A simple pepperpot device has been developed for characterizing the beam emittance. Plans for improving the power efficiency with the use of a new permanent magnet front plate is discussed.

  7. Dancing with the Electrons: Time-Domain and CW In Vivo EPR Imaging

    Directory of Open Access Journals (Sweden)

    Murali C. Krishna


    Full Text Available The progress in the development of imaging the distribution of unpaired electrons in living systems and the functional and the potential diagnostic dimensions of such an imaging process, using Electron Paramagnetic Resonance Imaging (EPRI, is traced from its origins with emphasis on our own work. The importance of EPR imaging stems from the fact that many paramagnetic probes show oxygen dependent spectral broadening. Assessment of in vivo oxygen concentration is an important factor in radiation oncology in treatment-planning and monitoring treatment-outcome. The emergence of narrow-line trairylmethyl based, bio-compatible spin probes has enabled the development of radiofrequency time-domain EPRI. Spectral information in time-domain EPRI can be achieved by generating a time sequence of T2* or T2 weighted images. Progress in CW imaging has led to the use of rotating gradients, more recently rapid scan with direct detection, and a combination of all the three. Very low field MRI employing Dynamic Nuclear polarization (Overhauser effect is also employed for monitoring tumor hypoxia, and re-oxygenation in vivo. We have also been working on the co-registration of MRI and time domain EPRI on mouse tumor models at 300 MHz using a specially designed resonator assembly. The mapping of the unpaired electron distribution and unraveling the spectral characteristics by using magnetic resonance in presence of stationary and rotating gradients in indeed ‘dancing with the (unpaired electrons’, metaphorically speaking.

  8. Superconducting Cavity Cryomodule Designs for the Next Generation of CW Linacs: Challenges and Options

    Energy Technology Data Exchange (ETDEWEB)

    Nicol, Thomas [Fermilab; Orlov, Yuriy [Fermilab; Peterson, Thomas [Fermilab; Yakovlev, Vyacheslav [Fermilab


    The designs of nearly all superconducting RF (SRF) linacs over the last several years, with one notable exception being CEBAF at Jefferson Lab, have assumed pulsed beam operation with relatively low duty factors. These include the XFEL at DESY, the ILC, the original configuration for Project X at Fermilab, as well as several others. Recently proposed projects, on the other hand, including the LCLS-II at SLAC, the newly configured low and medium energy sections for Project X, and FRIB at Michigan State, to name a few, assume continuous wave or CW operation on quite a large scale with ambitious gradients and cavity performance requirements. This has implications in the cavity design as well as in many parts of the overall cryomodule due to higher dynamic heat loads in the cavities themselves and higher heat loads in the input and high-order-mode (HOM) couplers. Piping internal to the cryomodule, the effectiveness of thermal intercepts, the size of integrated heat exchangers, and many other aspects of the overall design are also affected. This paper will describe some of these design considerations as we move toward the next generation of accelerator projects.

  9. Production of High Intracavity UV Power From a CW Laser Source (United States)

    David, R. T.; Chyba, T. H.; Keppel, C. E.; Gaskell, D.; Ent, R.


    The goal of this research project is to create a prototype high power CW source of ultraviolet (UV) photons for photon-electron scattering at the Thomas Jefferson National Accelerator Facility (TJNAF), Hall B. The facility will use optical resonant cavities to produce a high photon flux. The technical approach will be to frequency-double the 514.5 mn light from an Argon-Ion Laser to create 0.1 to 1.0 watt in the UV. The produced UV power will be stored in a resonant cavity to generate an high intracavity UV power of 102 to 103 watts. The specific aim of this project is to first design and construct the low-Q doubling cavity and lock it to the Argon-Ion wavelength. Secondly, the existing 514.5 nm high-Q build-up cavity and its locking electronics will be modified to create high intracavity UV power. The entire system will then be characterized and evaluated for possible beam line use.

  10. ARBRES: Light-Weight CW/FM SAR Sensors for Small UAVs

    Directory of Open Access Journals (Sweden)

    Xavier Fabregas


    Full Text Available This paper describes a pair of compact CW/FM airborne SAR systems for small UAV-based operation (wingspan of 3.5 m for low-cost testing of innovative SAR concepts. Two different SAR instruments, using the C and X bands, have been developed in the context of the ARBRES project, each of them achieving a payload weight below 5 Kg and a volume of 13.5 dm3 (sensor and controller. Every system has a dual receiving channel which allows operation in interferometric or polarimetric modes. Planar printed array antennas are used in both sensors for easy system integration and better isolation between transmitter and receiver subsystems. First experimental tests on board a 3.2 m wingspan commercial radio-controlled aircraft are presented. The SAR images of a field close to an urban area have been focused using a back-projection algorithm. Using the dual channel capability, a single pass interferogram and Digital Elevation Model (DEM has been obtained which agrees with the scene topography. A simple Motion Compensation (MoCo module, based on the information from an Inertial+GPS unit, has been included to compensate platform motion errors with respect to the nominal straight trajectory.

  11. Dancing with the Electrons: Time-Domain and CW EPR Imaging

    Directory of Open Access Journals (Sweden)

    Sankaran Subramanian


    Full Text Available The progress in the development of imaging the distribution of unpaired electrons in living systems and the functional and the potential diagnostic dimensions of such an imaging process, using Electron Paramagnetic Resonance Imaging (EPRI, is traced from its origins with emphasis on our own work. The importance of EPR imaging stems from the fact that many paramagnetic probes show oxygen dependent spectral broadening. Assessment of in vivo oxygen concentration is an important factor in radiation oncology in treatment-planning and monitoring treatment-outcome. The emergence of narrow-line trairylmethyl based, bio-compatible spin probes has enabled the development of radiofrequency time-domain EPRI. Spectral information in time-domain EPRI can be achieved by generating a time sequence of T 2 * or T 2 weighted images. Progress in CW imaging has led to the use of rotating gradients, more recently rapid scan with direct detection, and a combination of all the three. Very low field MRI employing Dynamic Nuclear polarization (Overhauser effect is also employed for monitoring tumor hypoxia, and re-oxygenation in vivo . We have also been working on the co-registration of MRI and time domain EPRI on mouse tumor models at 300 MHz using a specially designed resonator assembly. The mapping of the unpaired electron distribution and unraveling the spectral characteristics by using magnetic resonance in presence of stationary and rotating gradients in indeed ‘dancing with the ( unpaired electrons’, metaphorically speaking.

  12. Modeling of a CW Nd:YVO4 laser longitudinally pumped by high power VCSEL modules at 808 nm (United States)

    Alimohammadian, E.; Major, A.


    In this work longitudinal pumping of a continuous wave (CW) Nd:YVO4 laser by high power VCSEL modules was numerically studied. Two VCSEL pump modules (6 W and 15 W) were compared. The maximum output power from a Nd:YVO4 crystal using these pump modules was calculated to be 2.5 W and 6 W, respectively, using a 10 % output coupler. The slope and optical-to-optical efficiencies in both cases were around 47% and 40%, respectively. The performance of Nd:YVO4 crystal was found to be better than that of Nd:YAG crystal. Our numerical results indicate that VCSELs can serve as efficient pump sources for the end-pumped CW Nd:YVO4 lasers.

  13. First light curve analyses of binary systems AO Aqr, CW Aqr and ASAS 012206-4924.7 (United States)

    Ulaş, B.; Ulusoy, C.


    Using the data from the public database of the All Sky Automated Survey (ASAS) we performed the very first light curve analyses of the three eclipsing binary systems AO Aqr, CW Aqr and ASAS 012206-4924.7. The physical parameters of the systems were determined by the PHOEBE (Prša and Zwitter, 2005) software. From an analysis of the ASAS data it was concluded that AO Aqr was found to be a contact binary system while CW Aqr and ASAS 012206-4924.7 were found to be near-contact and detached binaries, respectively. Finally, the locations of the components, corresponding to the estimated physical parameters, in the HR diagram were also discussed.

  14. Self-injection-locking of a CW-OPO by intracavity frequency-doubling the idler wave. (United States)

    Lee, D H; Klein, M; Meyn, J P; Grob, P; Wallenstein, R; Boller, K


    We report on the observation of self-injection-locking of the signal wave of an optical parametric oscillator (OPO) with the intracavity frequency doubled idler wave. The two-mirror OPO is based on a periodically poled LiNbO3 (PPLN) crystal and pumped with a grating stabilized, continuous-wave (CW) single-frequency diode master-oscillator power-amplifier (MOPA) system. Simultaneous quasi-phase-matching (QPM) of OPO and second harmonic generation (SHG) is provided in the same crystal which carries two different domain gratings. The beat of the signal wave and the frequency-doubled idler wave is suppressed within a 500-kHz wide frequency range centered around zero as expected for self-injection- locking. The measurements prove the feasibility of optically phase-stabilized by-three-division of an optical frequency with CW-OPOs using cascaded nonlinearities.

  15. A 700 MHZ, 1 MW CW RF System for a FEL 100mA RF Photoinjector

    CERN Document Server

    Roybal, William; Reass, William; Rees, Daniel; Tallerico, Paul J; Torrez, Phillip A


    This paper describes a 700 MHz, 1 Megawatt CW, high efficiency klystron RF system utilized for a Free Electron Laser (FEL) high-brightness electron photoinjector (PI). The E2V klystron is mod-anode tube that operates with a beam voltage of 95 kV. This tube, operating with a 65% efficiency, requires ~96 watts of input power to produce in excess of 1 MW of output power. This output drives the 3rd cell of a 2½-cell, p-mode PI cavity through a pair of planar waveguide windows. Coupling is via a ridge-loaded tapered waveguide section and "dog-bone" iris. This paper will present the design of the RF, RF transport, coupling, and monitoring/protection systems that are required to support CW operations of the 100 mA cesiated, semi-porous SiC photoinjector.

  16. Evaluation of early rheumatic disorders in PIP joints using a cw-transillumination method: first clinical results (United States)

    Prapavat, Viravuth; Luhmann, Till; Krause, Andreas; Backhaus, Marina; Beuthan, Juergen; Mueller, Gerhard J.


    This paper presents first clinical results of an in vivo experimental study on the detection of early pathological changes of rheumatoid arthritis (RA) using a near IR cw- transillumination method on finger joints (PIP). The inflammation of a joint system when caused by RA leads to changes in the synovial membrane and synovial. Measurements have shown that these rheumatic induced processes results in a variation in optical properties within the joint system. Using a cw system the PIP-joint is transilluminated with diode lasers at the articular cavity in order to use the entire scattered distribution of the transmitted radiation intensity for diagnostic purposes. The study includes results of in vivo measurements on 24 joints with known status and the evaluation of the feasibility of different distribution properties for detection of early RA.

  17. 100 kW CW highly-efficient multi-beam klystron for a future electron-ion collider (United States)

    Teryaev, Vladimir E.; Shchelkunov, Sergey V.; Jiang, Yong; Hirshfield, Jay L.


    Initial results are presented for the development of a CW highly-efficient RF source needed for operation of a future electron-ion collider. The design of this compact multi-beam klystron yields high efficiency (above 70%) for the power output of 125 kW at 952.6 MHz. The klystron is to work for the RF systems for ion acceleration in the polarized Medium-energy Electron Ion Collider as being developed at Thomas Jefferson National Accelerator Facility.

  18. A deep-sea hydrothermal vent isolate, Pseudomonas aeruginosa CW961, requires thiosulfate for Cd tolerance and precipitation. (United States)

    Wang, Clifford L; Ozuna, Samantha C; Clark, Douglas S; Keasling, Jay D


    Pseudomonas aeruginosa CW961, an isolate from the vicinity of a deep-sea hydrothermal vent, grew in the presence of 5 mM Cd(2+) and removed Cd(2+) from solution. Sulfate was sufficient for growth when Cd(2+) was not present in the culture medium; however, thiosulfate was necessary for Cd(2+) precipitation and cell survival in the presence of Cd(2+).

  19. A deep-sea hydrothermal vent isolate, Pseudomonas aeruginosa CW961, requires thiosulfate for Cd2+ tolerance and precipitation (United States)

    Wang, Clifford L.; Ozuna, Samantha C.; Clark, Douglas S.; Keasling, Jay D.


    Pseudomonas aeruginosa CW961, an isolate from the vicinity of a deep-sea hydrothermal vent, grew in the presence of 5 mM Cd2+ and removed Cd2+ from solution. Sulfate was sufficient for growth when Cd2+ was not present in the culture medium; however, thiosulfate was necessary for Cd2+ precipitation and cell survival in the presence of Cd2+. PMID:20725529

  20. Use of monoclonal antibody-IRDye800CW bioconjugates in the resection of breast cancer. (United States)

    Korb, Melissa L; Hartman, Yolanda E; Kovar, Joy; Zinn, Kurt R; Bland, Kirby I; Rosenthal, Eben L


    Complete surgical resection of breast cancer is a powerful determinant of patient outcome, and failure to achieve negative margins results in reoperation in between 30% and 60% of patients. We hypothesize that repurposing Food and Drug Administration-approved antibodies as tumor-targeting diagnostic molecules can function as optical contrast agents to identify the boundaries of malignant tissue intraoperatively. The monoclonal antibodies bevacizumab, cetuximab, panitumumab, trastuzumab, and tocilizumab were covalently linked to a near-infrared fluorescence probe (IRDye800CW) and in vitro binding assays were performed to confirm ligand-specific binding. Nude mice bearing human breast cancer flank tumors were intravenously injected with the antibody-IRDye800 bioconjugates and imaged over time. Tumor resections were performed using the SPY and Pearl Impulse systems, and the presence or absence of tumor was confirmed by conventional and fluorescence histology. Tumor was distinguishable from normal tissue using both SPY and Pearl systems, with both platforms being able to detect tumor as small as 0.5 mg. Serial surgical resections demonstrated that real-time fluorescence can differentiate subclinical segments of disease. Pathologic examination of samples by conventional and optical histology using the Odyssey scanner confirmed that the bioconjugates were specific for tumor cells and allowed accurate differentiation of malignant areas from normal tissue. Human breast cancer tumors can be imaged in vivo with multiple optical imaging platforms using near-infrared fluorescently labeled antibodies. These data support additional preclinical investigations for improving the surgical resection of malignancies with the goal of eventual clinical translation. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Multi-kW cw fiber oscillator pumped by wavelength stabilized fiber coupled diode lasers (United States)

    Becker, Frank; Neumann, Benjamin; Winkelmann, Lutz; Belke, Steffen; Ruppik, Stefan; Hefter, Ulrich; Köhler, Bernd; Wolf, Paul; Biesenbach, Jens


    High power Yb doped fiber laser sources are beside CO2- and disk lasers one of the working horses of industrial laser applications. Due to their inherently given robustness, scalability and high efficiency, fiber laser sources are best suited to fulfill the requirements of modern industrial laser applications in terms of power and beam quality. Pumping Yb doped single-mode fiber lasers at 976nm is very efficient. Thus, high power levels can be realized avoiding limiting nonlinear effects like SRS. However the absorption band of Yb doped glass around 976nm is very narrow. Therefore, one has to consider the wavelength shift of the diode lasers used for pumping. The output spectrum of passively cooled diode lasers is mainly defined by the applied current and by the heat sink temperature. Furthermore the overall emission line width of a high power pump source is dominated by the large number of needed diode laser emitters, each producing an individual spectrum. Even though it is possible to operate multi-kW cw single-mode fiber lasers with free running diode laser pumps, wavelength stabilizing techniques for diode lasers (e.g. volume holographic gratings, VHG) can be utilized in future fiber laser sources to increase the output power level while keeping the energy consumption constant. To clarify the benefits of wavelength stabilized diode lasers with integrated VHG for wavelength locking the performance of a dual side pumped fiber oscillator is discussed in this article. For comparison, different pumping configurations consisting of stabilized and free-running diode lasers are presented.

  2. Synthesis, in vitro evaluation, and in vivo metabolism of fluor/quencher compounds containing IRDye 800CW and Black Hole Quencher-3 (BHQ-3). (United States)

    Linder, Karen E; Metcalfe, Edmund; Nanjappan, Palaniappa; Arunachalam, Thangavel; Ramos, Kimberly; Skedzielewski, Tina Marie; Marinelli, Edmund R; Tweedle, Michael F; Nunn, Adrian D; Swenson, Rolf E


    Protease-cleavable peptides containing a suitable fluor/quencher (Fl/Q) pair are optically dark until cleaved by their target protease, generating fluorescence. This approach has been used with many Fl/Q pairs, but little has been reported with IRDye 800CW, a popular near-infrared (NIR) fluor. We explored the use of the azo-bond-containing Black Hole Quencher 3 (BHQ-3) as a quencher for IRDye 800CW and found that IRDye 800CW/BHQ-3 is a suitable Fl/Q pair, despite the lack of proper spectral overlap for fluorescence resonance energy transfer (FRET) applications. Cleavage of IRDye 800CW-PLGLK(BHQ-3)AR-NH(2) (8) and its D-arginine (Darg) analogue (9) by matrix metalloproteinases (MMPs) in vitro yielded the expected cleavage fragments. In vivo, extensive metabolism was found. Significant decomposition of a "non-cleavable" control IRDye 800CW-(1,13-diamino-4,7,10-trioxatridecane)-BHQ-3 (10) was evident in plasma of normal mice by 3 min post injection. The major metabolite showed a m/z and UV/vis spectrum consistent with azo bond cleavage in the BHQ-3 moiety. Preparation of an authentic standard of this metabolite (11) confirmed the assignment. Although the IRDye 800CW/BHQ-3 constructs showed efficient contact quenching prior to enzymatic cleavage, BHQ-3 should be used with caution in vivo, due to instability of its azo bond.

  3. Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics. (United States)

    Franck, John M; Pavlova, Anna; Scott, John A; Han, Songi


    Liquid state Overhauser effect Dynamic Nuclear Polarization (ODNP) has experienced a recent resurgence of interest. The ODNP technique described here relies on the double resonance of electron spin resonance (ESR) at the most common, i.e. X-band (∼10GHz), frequency and ¹H nuclear magnetic resonance (NMR) at ∼15 MHz. It requires only a standard continuous wave (cw) ESR spectrometer with an NMR probe inserted or built into an X-band cavity. We focus on reviewing a new and powerful manifestation of ODNP as a high frequency NMR relaxometry tool that probes dipolar cross relaxation between the electron spins and the ¹H nuclear spins at X-band frequencies. This technique selectively measures the translational mobility of water within a volume extending 0.5-1.5 nm outward from a nitroxide radical spin probe that is attached to a targeted site of a macromolecule. It allows one to study the dynamics of water that hydrates or permeates the surface or interior of proteins, polymers, and lipid membrane vesicles. We begin by reviewing the recent advances that have helped develop ODNP into a tool for mapping the dynamic landscape of hydration water with sub-nanometer locality. In order to bind this work coherently together and to place it in the context of the extensive body of research in the field of NMR relaxometry, we then rephrase the analytical model and extend the description of the ODNP-derived NMR signal enhancements. This extended model highlights several aspects of ODNP data analysis, including the importance of considering all possible effects of microwave sample heating, the need to consider the error associated with various relaxation rates, and the unique ability of ODNP to probe the electron-¹H cross-relaxation process, which is uniquely sensitive to fast (tens of ps) dynamical processes. By implementing the relevant corrections in a stepwise fashion, this paper draws a consensus result from previous ODNP procedures and then shows how such data can be

  4. Design of the 3.7 GHz, 500 kW CW circulator for the LHCD system of the SST-1 tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Dixit, Harish V., E-mail: [Veermata Jijabai Technological Institute, Mumbai, Maharashtra 400019 (India); Jadhav, Aviraj R. [Veermata Jijabai Technological Institute, Mumbai, Maharashtra 400019 (India); Jain, Yogesh M. [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India); Cheeran, Alice N. [Veermata Jijabai Technological Institute, Mumbai, Maharashtra 400019 (India); Gupta, Vikas [Vidyavardhini' s College of Engineering and Technology, Vasai, Maharashtra 401202 (India); Sharma, P.K. [Institute for Plasma Research, Gandhinagar, Gujarat 382428 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094 (India)


    Highlights: • Design of a 500 kW CW circulator for LHCD system at 3.7 GHz. • Mechanism for thermal management of ferrite tile. • Scheme for uniform magnetisation of the ferrite tiles. • Design of high CW power CW quadrature and 180 ° hybrid coupler. - Abstract: Circulators are used in high power microwave systems to protect the vacuum source against reflection. The Lower Hybrid Current Drive (LHCD) system of SST-1 tokamak commissioned at IPR, Gandhinagar in India comprises of four high power circulators to protect klystrons (supplying 500 kW CW each at 3.7 GHz) which power the system. This paper presents the design of a Differential Phase Shift Circulator (DPSC) capable of handling 500 kW CW power at 3.7 GHz so that four circulators can be used to protect the four available klystrons. As the DPSC is composed by three main components, viz., magic tee, ferrite phase shifter and 3 dB hybrid coupler, the designing of each of the proposed components is described. The design of these components is carried out factoring various multiphysics aspects of RF, heating due to high CW power and magnetic field requirement of the ferrite phase shifter. The primary objective of this paper is to present the complete RF, magnetic and thermal design of a high CW power circulator. All the simulations have been carried out in COMSOL Multiphysics. The designed circulator exhibits an insertion loss of 0.13 dB with a worst case VSWR of 1.08:1. The total length of the circulator is 3 m.

  5. Research on quasi-cw and pulse interaction of strong laser radiation with the military technical materials (United States)

    Rycyk, Antoni; CzyŻ, Krzysztof; Sarzyński, Antoni; Skrzeczanowski, Wojciech; Ostrowski, Roman; Strzelec, Marek; Jach, Karol; Świerczyński, Robert


    The paper describes work connected to the investigation of the interaction of strong laser radiation with selected metals, constituting typical materials applied in military technology, like aluminum, copper, brass and titanium. A special laser experimental stand was designed and constructed to achieve this objective. The system consisted of two Nd:YAG lasers working in the regime of free generation (quasi-cw) and another Nd:YAG laser, generating short pre-pulses in the Qswitching regime. During the concurrent operation of both quasi-cw systems it was possible to obtain pulse energies amounting to 10 J in a time period (pulses) of 1 ms. The synchronized, serial operation resulted in energy amounting to 5 J over a time period (pulse) of 2 ms. Variations of the target's surface reflection coefficient, caused by the interaction of short pre-pulses with high power density were determined. The experiments were performed using a standard Nd:YAG laser with amplifiers, generating output pulses whose duration amounted to 10 ns and energy to 1 J, with near Gaussian profile. Laser induced breakdown spectroscopy (LIBS) was used to analyze the emission spectra of targets under the conditions of the interaction of destructive strong and weak as well as long and short excitation laser pulses. A decay of the spectra in the UV range from 200 to around 350 nm was observed when irradiating the target with a long, quasi-cw destructive pulse. Moreover, in the case of an Al target, some AlO molecular spectra appeared, suggesting a chemical reaction of the aluminum atoms with oxygen.

  6. HLA-Cw*04 allele associated with nevirapine-induced rash in HIV-infected Thai patients

    Directory of Open Access Journals (Sweden)

    Tunthanathip Preecha


    Full Text Available Abstract Background A high incidence of rash has been reported in HIV-1 patients who received the anti-retroviral drug nevirapine. In addition, several studies have suggested that polymorphisms of human leukocyte antigen (HLA genes may play important roles in nevirapine-induced rash. The aim of the present study was to evaluate the effects of different HLA-C alleles on rash associated with nevirapine in patients who started highly active anti-retroviral therapy (HAART containing nevirapine in Thailand. Results A case-control study was carried out involving HIV-1 patients under treatment at Bamrasnaradura Infectious Diseases Institute, Nonthaburi, Thailand between March 2007 and March 2008. The study included all HIV/AIDS patients being treated with nevirapine-containing regimens. The study population comprised 287 HIV/AIDS patients of whom 248 were nevirapine-tolerant and 39 developed rash after nevirapine treatment. From the nevirapine-tolerant patients, 60 were selected as the control group on the basis of age, sex, and therapy history matched for nevirapine-induced rash cases. We observed significantly more HLA-Cw*04 alleles in nevirapine-induced rash cases than in nevirapine-tolerant group, with frequencies of 20.51% and 7.50%, respectively (P = 0.009. There were no significant differences between the rash and tolerant groups for other HLA-C alleles except for HLA-Cw*03 (P = 0.015. Conclusion This study suggests that HLA-Cw*04 is associated with rash in nevirapine treated Thais. Future screening of patients' HLA may reduce the number of nevirapine-induced rash cases, and patients with alleles associated with nevirapine-induced rash should be started on anti-retroviral therapy without nevirapine.

  7. Characterizing fluorescent imaging properties of antibodies conjugated to IRDye800CW for use in imaging of head and neck cancer (United States)

    Foster, Robert C.; Krell, Asher M.; Chung, Thomas K.; Warram, Jason M.; Zinn, Kurt R.; Rosenthal, Eben L.


    Introduction: Proteins conjugated to the near infrared (NIR) moieties for detection of head and neck cancers are being translated to the clinic. However, little is known about the fluorescent properties of IRDye800CW after conjugation to antibodies. We investigated factors that may alter the real-time observed fluorescence of antibody conjugated dye and the rate of fluorescent signal loss. Methods: Signal loss was examined using three FDA approved monoclonal antibodies conjugated to IRDye800CW (LICOR) over a period of 15 days. Temperature effects on fluorescence were examined for conjugated dye in both solution and a mouse tumor model. Samples were cooled to -20°C then warmed to predetermined temperatures up to 60°C with imaging performed using the PEARL Impulse (LI-COR) and LUNA (Novadaq) systems. Results: Short term fluorescent signal loss (< 1 hour) was linear, while long term loss (15 days) was exponential with significant increases in rate observed with light exposure and increased temperatures. Cooling of tumor tissue at -20°C was shown to significantly increase tumor fluorescence on both imaging modalities when compared to room temperature (p=0.008, p=0.019). Concurrently the ratio of tumor to background fluorescent signal (TBR) increased with decreasing temperature with statistically significant increases seen at -20°C and 4°C (p=0.0015, p=0.03). Conclusions: TBR is increased with decreasing sample temperature, suggesting that the clinical exam of fluorescently labeled tissues may be improved at cooler temperatures. Our results indicate that both the rate of signal loss and the change in fluorescence with temperature observed for IRDye800CW are independent of the conjugating antibody.

  8. Development of a Time Synchronized CW-Laser Induced Fluorescence Measurement for Quasi-Periodic Oscillatory Plasma Discharges (United States)

    MacDonald, Natalia; Cappelli, Mark; Hargus, William, Jr.


    An advanced CW laser induced fluorescence diagnostic technique, capable of correlating high frequency current fluctuations to the resulting fluorescence excitation lineshapes, has been developed. This presentation describes this so-called ``Sample-Hold'' method of time-synchronization, and provides the steps taken to validate this technique, including simulations and experimental measurements on a 60 Hz Xe lamp discharge. Initial results for time-synchronized velocity measurements on the quasi-periodic oscillatory mode of a magnetic cusped plasma accelerator are also presented. These results show that the positions of the ionization and peak acceleration regions in the device vary over the course of a discharge current oscillation.

  9. Development of a 200 W CW high efficiency traveling wave tube at 12 GHz. [for use in communication technology satellites (United States)

    Christensen, J. A.; Tammaru, I.


    The design, development, and test results are reported for an experimental PPM focused, traveling-wave tube that produces 235 watts of CW RF power over 85 MHz centered at 12.080 GHz. The tube uses a coupled cavity RF circuit with a velocity taper for greater than 30 percent basic efficiency. Overall efficiency of 51 percent is achieved by means of a nine stage depressed collector designed at NASA Lewis Research Center. This collector is cooled by direct radiation to deep space.

  10. A simple digital system for tuning and long-term frequency stabilisation of a CW Ti:Sapphire laser


    Beterov, I. I.; Markovski, A.; Kobtsev, S. M.; Yakshina, E. A.; Entin, V. M.; Tretyakov, D. B.; Baraulya, V. I.; Ryabtsev, I. I.


    We have implemented a simple and cost-effective digital system for long-term frequency stabilisation and locking to an arbitrary wavelength of the single-frequency ring CW Ti:Sapphire laser. This system is built around two confocal Fabry-Perot cavities, one of which is used to narrow short-term line width of the laser and the other to improve long-term stability of the laser frequency. The second interferometer is also in the path of the radiation from an external-cavity diode laser stabilize...

  11. High-speed high-efficiency 500-W cw CO2 laser hermetization of metal frames of microelectronics devices (United States)

    Levin, Andrey V.


    High-speed, efficient method of laser surface treatment has been developed using (500 W) cw CO2 laser. The principal advantages of CO2 laser surface treatment in comparison with solid state lasers are the basis of the method. It has been affirmed that high efficiency of welding was a consequence of the fundamental properties of metal-IR-radiation (10,6 mkm) interaction. CO2 laser hermetization of metal frames of microelectronic devices is described as an example of the proposed method application.

  12. CW and Q-switched GGG/Er:Pr:GGG/GGG composite crystal laser at 2.7 µm (United States)

    You, Z. Y.; Wang, Y.; Sun, Y. J.; Xu, J. L.; Zhu, Z. J.; Li, J. F.; Wang, H. Y.; Tu, C. Y.


    We report the continuous-wave (CW) and passively Q-switched laser operations of a GGG/Er:Pr:GGG/GGG composite crystal at about 2.7 µm. Owing to the alleviation of the thermal lensing effect, the CW laser with a maximum output power of 463 mW was obtained with a slope efficiency of 15.5%. Based on the broadband saturable absorption property, a graphene saturable absorber (SA) mirror was fabricated and employed for realizing the Q-switched mid-infrared laser. Under an absorbed pump power of 2.47 W, an average output power of 186 mW was generated with a slope efficiency of 12.3%. The pulse width and the repetition rate of the laser were 360 ns and 120.5 kHz, respectively. These results indicate that the Er:Pr:GGG crystal, with the relatively lower upper-level lifetime, shows great promise for generating a short pulsed 2.7 µm mid-infrared laser using the graphene SA.

  13. Design of a 10 MeV normal conducting CW proton linac based on equidistant multi-gap CH cavities (United States)

    Li, Zhi-Hui


    Continuous wave (CW) high current proton linacs have wide applications as the front end of high power proton machines. The low energy part of such a linac is the most difficult and there is currently no widely accepted solution. Based on the analysis of the focusing properties of the CW low energy proton linac, a 10 MeV low energy normal conducting proton linac based on equidistant seven-gap Cross-bar H-type (CH) cavities is proposed. The linac is composed of ten 7-gap CH cavities and the transverse focusing is maintained by quadrupole doublets located between the cavities. The total length of the linac is less than 6 meters and the average acceleration gradient is about 1.2 MeV/m. The electromagnetic properties of the cavities are investigated by Microwave Studio. At the nominal acceleration gradient the maximum surface electric field in the cavities is less than 1.3 times the Kilpatrick limit, and the Ohmic loss of each cavity is less than 35 kW. Multi-particle beam dynamics simulations are performed with Tracewin code, and the results show that the beam dynamics of the linac are quite stable, the linac has the capability to accelerate up to 30 mA beam with acceptable dynamics behavior. Supported by National Natural Science Foundation of China (11375122, 91126003)

  14. Locations of radical species in black pepper seeds investigated by CW EPR and 9 GHz EPR imaging (United States)

    Nakagawa, Kouichi; Epel, Boris


    In this study, noninvasive 9 GHz electron paramagnetic resonance (EPR)-imaging and continuous wave (CW) EPR were used to investigate the locations of paramagnetic species in black pepper seeds without further irradiation. First, lithium phthalocyanine (LiPC) phantom was used to examine 9 GHz EPR imaging capabilities. The 9 GHz EPR-imager easily resolved the LiPC samples at a distance of ∼2 mm. Then, commercially available black pepper seeds were measured. We observed signatures from three different radical species, which were assigned to stable organic radicals, Fe3+, and Mn2+ complexes. In addition, no EPR spectral change in the seed was observed after it was submerged in distilled H2O for 1 h. The EPR and spectral-spatial EPR imaging results suggested that the three paramagnetic species were mostly located at the seed surface. Fewer radicals were found inside the seed. We demonstrated that the CW EPR and 9 GHz EPR imaging were useful for the determination of the spatial distribution of paramagnetic species in various seeds.

  15. High-field CW electron paramagnetic resonance spectroscopy with Gd(III) tags for structure-dynamics studies of proteorhodopsin (United States)

    Clayton, Jessica A.; Han, Chung-Ta; Wilson, C. Blake; Qi, Mian; Godt, Adelheid; Goldfarb, Daniella; Sherwin, Mark S.; Han, Songi

    Proteorhodopsin (PR) is a seven-helical transmembrane protein that functions as a light-activated proton pump. Much of the structure of PR has been mapped by solution-state NMR and X-ray crystallography, however it remains difficult to study protein associations and conformational changes. Here we report development of 240 GHz CW electron paramagnetic resonance (EPR) as a tool to determine inter- and intra-protein distances in the range of 1-4 nm under biologically relevant conditions, using S = 7/2 Gd(III)-based complexes as an EPR-active paramagnetic tag. The dipolar coupling between Gd(III) pairs is determined via the width of the central transition in the CW EPR spectrum, allowing for the inference of an interspin distance. Proof-of-principle experiments are demonstrated on Gd-ruler molecules, from cryogenic temperatures up to room temperature. First results applying this method to inter-protein measurement of Gd(III) tagged PR oligomers reveals distances consistent with the penta- or hexameric organization determined by crystal structure. Finally, we present progress towards development of measurement methods that will enable observation of light-induced conformational changes in the EF-loop region of PR at temperatures above the protein dynamical transition. This work is supported by NSF MCB-1617025 and NSF MCB-1244651.

  16. Pulsed vs. CW low level light therapy on osteoarticular signs and symptoms in limited scleroderma (CREST syndrome) (United States)

    Barolet, Daniel


    Limited cutaneous systemic sclerosis (lcSSc) was formerly known as CREST syndrome in reference to the associated clinical features: Calcinosis, Raynaud's phenomenon, Esophageal dysfunction, Sclerodactyly, and Telangiectasias. The transforming growth factor beta (TGF-β) has been identified has a major player in the pathogenic process, while low level light therapy (LLLT) has been shown to modulate this cytokine superfamily. This case study was conducted to assess the efficacy of 940nm using microsecond domain pulsing and continuous wave mode (CW) on osteoarticular signs and symptoms associated with lcSSc. The patient was treated two to three times a week for 13 weeks, using a sequential pulsing mode on one elbow, and a CW mode on the other. Efficacy assessments included inflammation, symptoms, pain, and health scales, patient satisfaction, clinical global impression, and adverse effects monitoring. Significant functional and morphologic improvements were observed after LLLT, with best results seen with the pulsing mode. No significant adverse effects were noted. Two mechanisms of action may be at play. The 940nm wavelength provides inside-out heating possibly vasodilating capillaries which in turn increases catabolic processes leading to a reduction of in situ calcinosis. LLLT may also improve symptoms by triggering a cascade of cellular reactions, including the modulation of inflammatory mediators.

  17. Effective Fluorescence Lifetime and Stimulated Emission Cross-Section of Nd/Cr:YAG Ceramics under CW Lamplight Pumping (United States)

    Saiki, Taku; Motokoshi, Shinji; Imasaki, Kazuo; Fujioka, Kana; Fujita, Hisanori; Nakatsuka, Masahiro; Izawa, Yasukazu; Yamanaka, Chiyoe


    Remarkable improvements in the lifetime of the Nd upper level and in the effective stimulated emission cross-section of Nd/Cr:YAG ceramics have been theoretically and experimentally studied. Until recently, it had been thought that the long energy transition time from Cr ions to Nd ions of Nd/Cr:YAG adversely affects laser action, degrading optical-optical conversion efficiency under CW and flash lamp pumping. However, current research showed that high-efficiency energy transition has a positive effect on laser action. The effective lifetime is increased from 0.23 to 1.1 ms and the emission cross-section is effectively increased to three times for that of the conventional Nd:YAG. A small signal gain is significantly improved, and the saturation power density is reduced to 1/10 that of the Nd:YAG for the same pumping power density. A CW laser light generated in a laser diode (LD)-pumped 1064 nm Nd:YAG laser oscillator was amplified, and the measured output power was saturated. The output laser power calculated using theoretical saturation power density was consistent with the experimental results.

  18. Photovoltaic concentrator application experiment, Phase I: a 150 KW photovoltaic concentrator power system for load-center applications with feedback into the utility grid. Final report, June 1, 1978--March 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Noel, G T; Alexander, G; Stember, L H; Stickford, G H; Smail, H E; Broehl, J H; Carmichael, D C


    A 150-kW-peak concentrator-type photovoltaic power system to supply a multiple building load application in the Columbus, Ohio area was designed and analyzed by a Battelle-led team. The system will operate in parallel with the utility grid (which provides backup power) to supply either or both of two service/commercial buildings and will feed surplus power into the utility grid. The array consists of fifteen 10-kW carousel-mounted subarrays which are two-axis tracking. The subarrays each consist of 40 passively cooled concentrating modules which incorporate a primary parabolic trough reflector and a secondary compound-elliptic concentrator to achieve a geometric concentration ratio of approx. 26. The power conditioning subsystem is microprocessor controlled, with maximum-power-point tracking and automatic control capabilities. The system performance analysis indicates that the system will supply approximately 147,000 kWh/year to the primary load and an additional 55,000 kWh/year to the utility grid, in the single-load operational mode. The system design and the daily and seasonal match of system output with the load are described in detail. Plans are also discussed for installation and for operational evaluations of performance, economics, and institutional issues.

  19. A method of laser micro-polishing for metallic surface using UV nano-second pulse and CW lasers

    CERN Document Server

    Jang, Pong-Ryol; Ji, Kum-Hyok; Kim, Nam-Chol


    During laser micro-polishing, the constant control of laser energy density is a key technology to improve the surface roughness. In this paper, a method which controls the energy density of UV(ultraviolet) pulse laser in real time with the control of CW(continuous wave) laser spot size in laser micro-polishing for metallic surface was presented. The experimental and analytical considerations of several influence factors such as laser spot size, fusion zone and focal offset were investigated. In addition, using a laser micro-polishing system manufactured with this method, the laser micro-polishing experiments on the two different surface shapes of stainless steel 316L were conducted. For the inclined or curved surface, the surface roughness improvements of up to 56.4% and 57.3% were respectively obtained, and the analysis of the results were discussed.

  20. Progress in Cr and Fe doped ZnS/Se mid-IR CW and femtosecond lasers (United States)

    Vasilyev, Sergey; Moskalev, Igor; Mirov, Mike; Smolski, Viktor; Martyshkin, Dmitry; Fedorov, Vladimir; Mirov, Sergey; Gapontsev, Valentin


    This paper summarizes recent improvements of output characteristics of polycrystalline Cr:ZnS/Se master oscillators in Kerr-Lens-Mode-Locked regime. We developed a flexible design of femtosecond polycrystalline Cr:ZnS and Cr:ZnSe lasers and amplifiers in the spectral range 2-3 μm. We obtained few-optical-cycle pulses with multi-Watt average power in very broad range of repetition rates 0.08-1.2 GHz. We also report on efficient nonlinear frequency conversion directly in the polycrystalline gain elements of ultra-fast lasers and amplifiers. In this work we also report on recent progress in spinning ring gain element technology and report to the best of our knowledge the highest output power of 9.2 W Fe:ZnSe laser operating in CW regime at 4150nm.


    Directory of Open Access Journals (Sweden)

    Mircea UDREA


    Full Text Available Preliminary results obtained in developing a visualisation technique for non-invasive analysis of air flow inside INCAS subsonic wind tunnel and its appendages are presented. The visualisation technique is based on using a green light sheet generated by a continuous wave (cw longitudinally diode pumped and frequency doubled Nd:YAG laser. The output laser beam is expanded on one direction and collimated on rectangular direction. The system is tailored to the requirements of qualitative analysis and vortex tracking requirements inside the INCAS 2.5m x 2.0m subsonic wind tunnel test section, for measurements performed on aircraft models. Also the developed laser techniques is used for non-invasive air flow field analysis into environmental facilities settling room (air flow calming area. Quantitative analysis is enabled using special image processing tools upon movies and pictures obtained during the experiments. The basic experimental layout in the wind tunnel takes advantage of information obtained from the investigation of various aircraft models using the developed visualisation technique. These results are further developed using a Particle Imaging Velocimetry (PIV experimental technique.The focus is on visualisation techniques to be used for wind flow characterization at different altitudes in indus-trial and civil buildings areas using a light sheet generated by a Nd:YAG cw pumped and doubled laser at 532 nm wave-length. The results are important for prevention of biological/chemical disasters such as spreading of extremely toxic pol-lutants due to wind. Numerical simulations of wind flow and experimental visualisation results are compared. A good agreement between these results is observed.

  2. Magnetization transfer effect on the creatine methyl resonance studied by CW off-resonance irradiation in human skeletal muscle on a clinical MR system.

    NARCIS (Netherlands)

    Renema, W.K.J.; Klomp, D.W.J.; Philippens, M.E.P.; Bergh, A.J. van den; Wieringa, B.; Heerschap, A.


    Magnetization transfer (MT) between the mobile (MR-visible) spin pool and immobile (MR-invisible) spin pool of creatine (Cr) was studied on a clinical 1.5 T MR scanner in human skeletal muscle using continuous wave (CW) pre-irradiation as the saturation method for the immobile pool. For this

  3. Intracavity-Pumped Raman Laser Action in a Mid-IR, Continuous-Wave (cw) MgO:PPLN Optical Parametric Oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Okishev, A.V.; Zuegel, J.D.


    Intracavity-pumped Raman laser action in a fiber-laser–pumped, single-resonant, continuous-wave (cw) MgO:PPLN optical parametric oscillator with a high-Q linear resonator has been observed for the first time to our knowledge. Experimental results of this phenomenon investigation will be discussed.

  4. Intracavity-pumped Raman laser action in a mid IR, continuous-wave (cw) MgO:PPLN optical parametric oscillator. (United States)

    Okishev, Andrey V; Zuegel, Jonathan D


    Intracavity-pumped Raman laser action in a fiber-laser-pumped, single-resonant, continuous-wave (cw) MgO:PPLN optical parametric oscillator with a high-Q linear resonator has been observed for the first time to our knowledge. Experimental results of this phenomenon investigation will be discussed.

  5. Demonstration of frequency control and CW diode laser injection control of a titanium-doped sapphire ring laser with no internal optical elements (United States)

    Bair, Clayton H.; Brockman, Philip; Hess, Robert V.; Modlin, Edward A.


    Theoretical and experimental frequency narrowing studies of a Ti:sapphire ring laser with no intracavity optical elements are reported. Frequency narrowing has been achieved using a birefringent filter between a partially reflecting reverse wave suppressor mirror and the ring cavity output mirror. Results of CW diode laser injection seeding are reported.

  6. Effect of corn steep liquor (CSL) and cassava wastewater (CW) on chitin and chitosan production by Cunninghamella elegans and their physicochemical characteristics and cytotoxicity. (United States)

    Berger, Lúcia Raquel Ramos; Stamford, Thayza Christina Montenegro; Stamford-Arnaud, Thatiana Montenegro; de Oliveira Franco, Luciana; do Nascimento, Aline Elesbão; Cavalcante, Horacinna M de M; Macedo, Rui Oliveira; de Campos-Takaki, Galba Maria


    Microbiological processes were used for chitin and chitosan production with Cunninghamella elegans UCP/WFCC 0542 grown in different concentrations of two agro-industrial wastes, corn steep liquor (CSL) and cassava wastewater (CW) established using a 2² full factorial design. The polysaccharides were extracted by alkali-acid treatment and characterized by infrared spectroscopy, viscosity, thermal analysis, elemental analysis, scanning electron microscopy and X-ray diffraction. The cytotoxicity of chitosan was evaluated for signs of vascular change on the chorioallantoic membrane of chicken eggs. The highest biomass (9.93 g/L) was obtained in trial 3 (5% CW, 8% CSL), the greatest chitin and chitosan yields were 89.39 mg/g and 57.82 mg/g, respectively, and both were obtained in trial 2 (10% CW, 4% CSL). Chitin and chitosan showed a degree of deacetylation of 40.98% and 88.24%, and a crystalline index of 35.80% and 23.82%, respectively, and chitosan showed low molecular weight (LMW 5.2 × 10³ Da). Chitin and chitosan can be considered non-irritating, due to the fact they do not promote vascular change. It was demonstrated that CSL and CW are effective renewable agroindustrial alternative substrates for the production of chitin and chitosan.

  7. Effect of vegetation type on treatment performance and bioelectric production of constructed wetland modules combined with microbial fuel cell (CW-MFC) treating synthetic wastewater. (United States)

    Saz, Çağdaş; Türe, Cengiz; Türker, Onur Can; Yakar, Anıl


    An operation of microcosm-constructed wetland modules combined with microbial fuel cell device (CW-MFC) was assessed for wastewater treatment and bioelectric generation. One of the crucial aims of the present experiment is also to determine effect of vegetation on wastewater treatment process and bioelectric production in wetland matrix with microbial fuel cell. Accordingly, CW-MFC modules with vegetation had higher treatment efficiency compared to unplanted wetland module, and average COD, NH4+, and TP removal efficiency in vegetated wetland modules were ranged from 85 to 88%, 95 to 97%, and 95 to 97%, respectively. However, the highest NO3- removal (63%) was achieved by unplanted control module during the experiment period. The maximum average output voltage, power density, and Coulombic efficiency were obtained in wetland module vegetated with Typha angustifolia for 1.01 ± 0.14 V, 7.47 ± 13.7 mWatt/m2, and 8.28 ± 10.4%, respectively. The results suggest that the presence of Typha angustifolia vegetation in the CW-MFC matrix provides the benefits for treatment efficiency and bioelectric production; thus, it increases microbial activities which are responsible for biodegradation of organic compounds and catalyzed to electron flow from anode to cathode. Consequently, we suggest that engineers can use vegetated wetland matrix with Typha angustifolia in CW-MFC module in order to maximize treatment efficiency and bioelectric production.

  8. Characteristics of the evolution of a plasma generated by radiation from CW and repetitively pulsed CO2 lasers in different gases (United States)

    Kanevskii, M. F.; Stepanova, M. A.


    The interaction between high-power CW and repetitively pulsed CO2 laser radiation and a low-threshold optical-breakdown plasma near a metal surface is investigated. The characteristics of the breakdown plasma are examined as functions of the experimental conditions. A qualitative analysis of the results obtained was performed using a simple one-dimensional model for laser combustion waves.

  9. Effect of Corn Steep Liquor (CSL and Cassava Wastewater (CW on Chitin and Chitosan Production by Cunninghamella elegans and Their Physicochemical Characteristics and Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Lúcia Raquel Ramos Berger


    Full Text Available Microbiological processes were used for chitin and chitosan production with Cunninghamella elegans UCP/WFCC 0542 grown in different concentrations of two agro-industrial wastes, corn steep liquor (CSL and cassava wastewater (CW established using a 22 full factorial design. The polysaccharides were extracted by alkali-acid treatment and characterized by infrared spectroscopy, viscosity, thermal analysis, elemental analysis, scanning electron microscopy and X-ray diffraction. The cytotoxicity of chitosan was evaluated for signs of vascular change on the chorioallantoic membrane of chicken eggs. The highest biomass (9.93 g/L was obtained in trial 3 (5% CW, 8% CSL, the greatest chitin and chitosan yields were 89.39 mg/g and 57.82 mg/g, respectively, and both were obtained in trial 2 (10% CW, 4% CSL. Chitin and chitosan showed a degree of deacetylation of 40.98% and 88.24%, and a crystalline index of 35.80% and 23.82%, respectively, and chitosan showed low molecular weight (LMW 5.2 × 103 Da. Chitin and chitosan can be considered non-irritating, due to the fact they do not promote vascular change. It was demonstrated that CSL and CW are effective renewable agroindustrial alternative substrates for the production of chitin and chitosan.

  10. High-effective denitrification of low C/N wastewater by combined constructed wetland and biofilm-electrode reactor (CW-BER). (United States)

    He, Yuan; Wang, Yuhui; Song, Xinshan


    The low denitrification effect on constructed wetlands (CWs) treating low carbon to nitrogen ratio (C/N) wastewater was a problem. In this study, a novel coupled system by installing CW and biofilm-electrode reactor (CW-BER) was developed. In this system, the heterotrophic and autotrophic denitrifying bacteria all played their roles in denitrification process. The system was investigated systematically with simulated wastewater at different C/Ns, electric current intensities (I), hydraulic retention times (HRTs), and pH. Results showed that the optimum running conditions were C/N=0.75-1, I=15 mA, HRT=12 h, and pH=7.5. The highest removal efficiency of NO3-N and TN at the best conditions was respectively 63.03% and 98.11% for CW-BER. Also, the TN and NO3-N enhancive removal efficiency of CW-BER was 23.26% and 24.20%, respectively. No residual organic carbon source was detected in final effluent at the best parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Rietvlei (CW24) and Diep (CW25)

    CSIR Research Space (South Africa)

    Grindley, JR


    Full Text Available . This report is part of a series on Cape Estuaries being published under the general title "The Estuaries of the Cape, Part 2". The report entails available historical information on Rietvlei and Diep estuary and abiotic and biotic characteristics found...

  12. Use of the 2-μm cw laser as addition and/or alternative for the Nd:YAG in urology (United States)

    de Boorder, Tjeerd; Verdaasdonk, Rudolf; Lock, Tycho; Grimbergen, Matthijs; Klaessens, John


    Recently, 2 μm cw laser systems have been introduced for surgery. The 2 μm wavelength is predominantly absorbed by water and enables effective cutting and ablation of tissue similar to the cw CO II laser. In contrast to the CO II laser, the 2 μm wavelength is delivered through fiber optics and available for endoscopic procedures. After many years of experience with the 1.06 μm Nd:YAG laser, we started to use the 2 μm cw laser as alternative for various urological treatments. The treatments strategies and optimal settings were examined in the lab comparing the two 1.06 and 2 μm wavelengths performing thermal measurements. Consequently, the laser was applied for various urological cases. Penile tumors were resected with haemostatic effects and good aesthetic healing comparable with the Nd:YAG laser. Although the Nd:YAG has initially a deeper penetration, the blackening of the fiber during tissue cutting, provides a more superficial effect like the 2 μm laser. Bladder (pre)malignancies were ablated after biopsy. Only with higher stage tumors, coagulation depth of the Nd:YAG might be preferable for adequate treatment. Strictures in the urethra were incised and stents were effectively desobstructed: one patient with a stent implanted after a pelvic trauma, and one patient with catheterizable apedico stoma stenoses. The thermal damage during incision to deeper layers is minimal so recurrence due to scarring is not expected. Also hair grow in patients who underwent urethroplasty was effectively treated and scrotal atheromata cysts were effectively resected without recurrence. Laparoscopic nefrectomies are being considered using the 2 μm cw laser. The 2 μm cw laser has shown to be a versatile instrument for effective treatment of various urological indications. More patients and long term results are needed to prove the clinical significance compared to other treatment modalities

  13. Thermal stability of Cpl-7 endolysin from the streptococcus pneumoniae bacteriophage Cp-7; cell wall-targeting of its CW_7 motifs. (United States)

    Bustamante, Noemí; Rico-Lastres, Palma; García, Ernesto; García, Pedro; Menéndez, Margarita


    Endolysins comprise a novel class of selective antibacterials refractory to develop resistances. The Cpl-7 endolysin, encoded by the Streptococcus pneumoniae bacteriophage Cp-7, consists of a catalytic module (CM) with muramidase activity and a cell wall-binding module (CWBM) made of three fully conserved CW_7 repeats essential for activity. Firstly identified in the Cpl-7 endolysin, CW_7 motifs are also present in a great variety of cell wall hydrolases encoded, among others, by human and live-stock pathogens. However, the nature of CW_7 receptors on the bacterial envelope remains unknown. In the present study, the structural stability of Cpl-7 and the target recognized by CW_7 repeats, relevant for exploitation of Cpl-7 as antimicrobial, have been analyzed, and transitions from the CM and the CWBM assigned, using circular dichroism and differential scanning calorimetry. Cpl-7 stability is maximum around 6.0-6.5, near the optimal pH for activity. Above pH 8.0 the CM becomes extremely unstable, probably due to deprotonation of the N-terminal amino-group, whereas the CWBM is rather insensitive to pH variation and its structural stabilization by GlcNAc-MurNAc-l-Ala-d-isoGln points to the cell wall muropeptide as the cell wall target recognized by the CW_7 repeats. Denaturation data also revealed that Cpl-7 is organized into two essentially independent folding units, which will facilitate the recombination of the CM and the CWBM with other catalytic domains and/or cell wall-binding motifs to yield new tailored chimeric lysins with higher bactericidal activities or new pathogen specificities.

  14. Thermal stability of Cpl-7 endolysin from the streptococcus pneumoniae bacteriophage Cp-7; cell wall-targeting of its CW_7 motifs.

    Directory of Open Access Journals (Sweden)

    Noemí Bustamante

    Full Text Available Endolysins comprise a novel class of selective antibacterials refractory to develop resistances. The Cpl-7 endolysin, encoded by the Streptococcus pneumoniae bacteriophage Cp-7, consists of a catalytic module (CM with muramidase activity and a cell wall-binding module (CWBM made of three fully conserved CW_7 repeats essential for activity. Firstly identified in the Cpl-7 endolysin, CW_7 motifs are also present in a great variety of cell wall hydrolases encoded, among others, by human and live-stock pathogens. However, the nature of CW_7 receptors on the bacterial envelope remains unknown. In the present study, the structural stability of Cpl-7 and the target recognized by CW_7 repeats, relevant for exploitation of Cpl-7 as antimicrobial, have been analyzed, and transitions from the CM and the CWBM assigned, using circular dichroism and differential scanning calorimetry. Cpl-7 stability is maximum around 6.0-6.5, near the optimal pH for activity. Above pH 8.0 the CM becomes extremely unstable, probably due to deprotonation of the N-terminal amino-group, whereas the CWBM is rather insensitive to pH variation and its structural stabilization by GlcNAc-MurNAc-l-Ala-d-isoGln points to the cell wall muropeptide as the cell wall target recognized by the CW_7 repeats. Denaturation data also revealed that Cpl-7 is organized into two essentially independent folding units, which will facilitate the recombination of the CM and the CWBM with other catalytic domains and/or cell wall-binding motifs to yield new tailored chimeric lysins with higher bactericidal activities or new pathogen specificities.

  15. SU-F-T-85: Energy Modulated Electron Postmastectomy Unreconstructed (PU) Chest Wall (CW) Irradiation Technique to Achieve Heart Sparing

    Energy Technology Data Exchange (ETDEWEB)

    Hong, L; Ballangrud, A; Mechalakos, J [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); McCormick, B [Memerial Sloan-Kettering Cancer Center, New York, NY (United States)


    Purpose: For left-sided PU patients requiring CW and nodal irradiation, sometimes partial wide tangents (PWT) are not feasible due to abnormal chest wall contour or heart position close to the anterior chest wall or unusual wide excision scar. We developed an energy modulated electron chest wall irradiation technique that will achieve heart sparing. Methods: Ten left-sided PU patients were selected for this dosimetry study. If PWT were used, the amount of the ipsilateral lung would be ranged 3.4 to 4.4 cm, and the amount of heart would be ranged 1.3 to 3.8 cm. We used electron paired fields that matched on the skin to achieve dose conformity to the chest wall. The enface electron fields were designed at extended SSD from a single isocenter and gantry angle with different energy beams using different cutout. Lower energy was used in the central chest wall part and higher energy was used in the periphery of the chest wall. Bolus was used for the electron fields to ensure adequate skin dose coverage. The electron fields were matched to the photon supra-clavicle field in the superior region. Daily field junctions were used to feather the match lines between all the fields. Target volumes and normal tissues were drawn according to institutional protocols. Prescription dose was 2Gy per fraction for a total 50Gy. Dose calculations were done with Eclipse EMC-11031 for Electron and AAA-11031 for photons. Results: Six patients were planned using 6/9MeV, three using 9/12MeV and one 6/12MeV. Target volumes achieved adequate coverage. For heart, V30Gy, V20Gy and Mean Dose were 0.6%±0.6%, 2.7%±1.7%, and 3.0Gy±0.8Gy respectively. For ipsilateral lung, V50Gy, V20Gy, V10Gy and V5Gy were 0.9%±1.1%, 34.3%±5.1%, 51.6%±6.3% and 64.1%±7.5% respectively. Conclusion: For left-sided PU patients with unusual anatomy, energy modulated electron CW irradiation technique can achieve heart sparing with acceptable lung dose.

  16. Intact anthracene inhibits photosynthesis in algal cells: a fluorescence induction study on Chlamydomonas reinhardtii cw92 strain. (United States)

    Aksmann, Anna; Tukaj, Zbigniew


    Short-term (24h) experiments were performed to examine the effect of anthracene (ANT) on Chlamydomonas reinhardtii cw92 grown in a batch culture system aerated with 2.5% CO(2). At concentrations ranging from 0.7 to 5.6 microM, ANT inhibited the growth of population in a concentration-dependent manner and EC(50) calculated amounted to 1.6 microM. At concentrations from 0.7 to 4.2 microM ANT stimulated respiration and inhibited the intensity of photosynthesis but did not affect chlorophyll content in the cells. ANT influenced chlorophyll a fluorescence parameters, measured by OJIP test (O, J, I and P are the different steps of fluorescence induction curve). ANT diminished the performance index (PI), the yield of primary photochemistry (phi(Po)), the yield of electron transport (phi(Epsilonomicron), the efficiency of moving the electron beyond Qa(-) (Psi(0)) and the fraction of active oxygen evolving complexes (OEC). The fraction of active PS II reaction centres in the treated samples dramatically dropped. The most pronounced changes in ANT-treated cells were observed in the stimulation of energy dissipation parameter (DI(0)/RC). The only OJIP parameter that was not influenced by ANT was energy absorption by photosynthetic antennae (ABS). The results lead to a conclusion that the inhibition of photosynthesis may be a consequence of unspecific ANT-membrane interaction, resulting from hydrophobic character of this hydrocarbon.

  17. Three new bands of 18O16O18O by CW-CRDS between 6340 and 6800 cm-1 (United States)

    Starikova, E.; Barbe, A.; De Backer, M.-R.; Tyuterev, Vl. G.; Mondelain, D.; Kassi, S.; Campargue, A.


    Three very weak bands of the 18O16O18O isotopologue of ozone have been detected by high sensitivity CW-Cavity Ring Down Spectroscopy between 6340 and 6800 cm-1. They are vibrationally assigned as 2ν1+5ν3, ν1+4ν2+3ν3 and 3ν2+5ν3 and correspond to the highest frequency bands of this isotopologue detected so far. A total of 464, 318 and 194 transitions were rovibrationally assigned, respectively. The good agreement with theoretical values achieved for the derived band centres and rotational constants confirms the accuracy of the potential energy surface recently obtained via extensive ab initio calculations. A set of line intensities was measured and fitted to derive the first transition moment parameter of the three bands. The determined sets of effective Hamiltonian parameter and transition moment operators, as well as the experimental energy levels, were used to generate a complete list of 1526 transitions, provided as Supplementary materials. The calculated line-list allows generating a synthetic spectrum which reproduces satisfactorily the experimental spectrum.

  18. Numerical simulation and experimental investigation of Ti-6Al-4V melted by CW fiber laser at different pressures (United States)

    Tabassum, Aasma; Zhou, Jie; Han, Bing; Ni, Xiao-wu; Sardar, Maryam


    The interaction of continuous wave (CW) fiber laser with Ti-6Al-4V alloy is investigated numerically and experimentally at different laser fluence values and ambient pressures of N2 atmosphere to determine the melting time threshold of Ti-6Al-4V alloy. A 2D-axisymmetric numerical model considering heat transfer and laminar flow is established to describe the melting process. The simulation results indicate that material melts earlier at lower pressure (8.0 Pa) than at higher pressure (8.8×104 Pa) in several milliseconds with the same laser fluence. The experimental results demonstrate that the melting time threshold at high laser fluence (above 1.89×108 W/m2) is shorter for lower pressure (vacuum), which is consistent with the simulation. While the melting time threshold at low laser fluence (below 1.89×108 W/m2) is shorter for higher pressure. The possible aspects which can affect the melting process include the increased heat loss induced by the heat conduction between the metal surface and the ambient gas with the increased pressure, and the absorption variation of the coarse surface resulted from the chemical reaction.

  19. Heat-sink free CW operation of injection microdisk lasers grown on Si substrate with emission wavelength beyond 1.3  μm. (United States)

    Kryzhanovskaya, Natalia; Moiseev, Eduard; Polubavkina, Yulia; Maximov, Mikhail; Kulagina, Marina; Troshkov, Sergey; Zadiranov, Yury; Guseva, Yulia; Lipovskii, Andrey; Tang, Mingchu; Liao, Mengya; Wu, Jiang; Chen, Siming; Liu, Huiyun; Zhukov, Alexey


    High-performance injection microdisk (MD) lasers grown on Si substrate are demonstrated for the first time, to the best of our knowledge. Continuous-wave (CW) lasing in microlasers with diameters from 14 to 30 μm is achieved at room temperature. The minimal threshold current density of 600  A/cm2 (room temperature, CW regime, heatsink-free uncooled operation) is comparable to that of high-quality MD lasers on GaAs substrates. Microlasers on silicon emit in the wavelength range of 1320-1350 nm via the ground state transition of InAs/InGaAs/GaAs quantum dots. The high stability of the lasing wavelength (dλ/dI=0.1  nm/mA) and the low specific thermal resistance of 4×10-3°C×cm2/W are demonstrated.

  20. CW blue-green light emission from GaN and SiC by sum-frequency generation and second harmonic generation (United States)

    Chao, L. C.; Steckl, A. J.


    Continuous wave (CW) back-scattered sum-frequency generation (SFG) and second harmonic generation (SHG) have been obtained from GaN and SiC. GaN samples were obtained from GaN films grown by molecular-beam epitaxy (MBE), metalorganic chemical-vapor deposition and hydride vapor-phase epitaxy. The SiC samples were obtained from 3C SiC/Si grown by chemical vapor deposition (CVD), 4H and 6H single crystal SiC substrates. The samples were optically excited with two CW lasers at the red (840 nm) and the infrared (1.0 µm). SHG at 420 nm and 500 nm and SFG at 455 nm were observed. SFG and SHG were verified by measuring their relative intensities against the pumping laser power. The SHG signals from GaN and SiC samples are compared with that from KH2PO4 (KDP).

  1. Characterization of the optical beam emitted by high-power phase-locked arrays of diode lasers (P = 1 W CW) (United States)

    Sobczak, Grzegorz; Dabrowska, ElŻbieta; Teodorczyk, Marian; Kalbarczyk, Joanna; Malag, Andrzej


    The quality of the beam emitted by high-power laser diodes is still the main disadvantage of these devices. One of the ways to improve it is to design diode as a matrix of narrow active stripes - so called: phase-locked arrays. The optical coupling which is occurs in such devices causes the emission in the form of a few almost diffraction limited beams (lobes). Unfortunately, because of temperature dependence of refractive indices this coupling often disappears at high drive currents. In this paper the CW operation (up to 4Ith) of the phase-locked semiconductor laser arrays is reported. The devices are based on asymmetric heterostructure which is designed for improving thermal and electrical resistances. The single supermode operation is obtained and the lasers are emitted up to 1 W of the optical power in CW.

  2. 2-GHz band CW and W-CDMA modulated radiofrequency fields have no significant effect on cell proliferation and gene expression profile in human cells. (United States)

    Sekijima, Masaru; Takeda, Hiroshi; Yasunaga, Katsuaki; Sakuma, Noriko; Hirose, Hideki; Nojima, Toshio; Miyakoshi, Junji


    We investigated the mechanisms by which radiofrequency (RF) fields exert their activity, and the changes in both cell proliferation and the gene expression profile in the human cell lines, A172 (glioblastoma), H4 (neuroglioma), and IMR-90 (fibroblasts from normal fetal lung) following exposure to 2.1425 GHz continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) RF fields at three field levels. During the incubation phase, cells were exposed at the specific absorption rates (SARs) of 80, 250, or 800 mW/kg with both CW and W-CDMA RF fields for up to 96 h. Heat shock treatment was used as the positive control. No significant differences in cell growth or viability were observed between any test group exposed to W-CDMA or CW radiation and the sham-exposed negative controls. Using the Affymetrix Human Genome Array, only a very small (CDMA RF fields for up to 96 h did not act as an acute cytotoxicant in either cell proliferation or the gene expression profile. These results suggest that RF exposure up to the limit of whole-body average SAR levels as specified in the ICNIRP guidelines is unlikely to elicit a general stress response in the tested cell lines under these conditions.

  3. Pulsed and CW adjustable 1942 nm single-mode all-fiber Tm-doped fiber laser system for surgical laser soft tissue ablation applications. (United States)

    Huang, Yize; Jivraj, Jamil; Zhou, Jiaqi; Ramjist, Joel; Wong, Ronnie; Gu, Xijia; Yang, Victor X D


    A surgical laser soft tissue ablation system based on an adjustable 1942 nm single-mode all-fiber Tm-doped fiber laser operating in pulsed or CW mode with nitrogen assistance is demonstrated. Ex vivo ablation on soft tissue targets such as muscle (chicken breast) and spinal cord (porcine) with intact dura are performed at different ablation conditions to examine the relationship between the system parameters and ablation outcomes. The maximum laser average power is 14.4 W, and its maximum peak power is 133.1 W with 21.3 μJ pulse energy. The maximum CW power density is 2.33 × 106 W/cm2 and the maximum pulsed peak power density is 2.16 × 107 W/cm2. The system parameters examined include the average laser power in CW or pulsed operation mode, gain-switching frequency, total ablation exposure time, and the input gas flow rate. The ablation effects were measured by microscopy and optical coherence tomography (OCT) to evaluate the ablation depth, superficial heat-affected zone diameter (HAZD) and charring diameter (CD). Our results conclude that the system parameters can be tailored to meet different clinical requirements such as ablation for soft tissue cutting or thermal coagulation for future applications of hemostasis.

  4. CW EPR and 9 GHz EPR imaging investigation of stable paramagnetic species and their antioxidant activities in dry shiitake mushroom (Lentinus edodes). (United States)

    Nakagawa, Kouichi; Hara, Hideyuki


    We investigated the antioxidant activities and locations of stable paramagnetic species in dry (or drying) shiitake mushroom (Lentinus edodes) using continuous wave (CW) electron paramagnetic resonance (EPR) and 9 GHz EPR imaging. CW 9 GHz EPR detected paramagnetic species (peak-to-peak linewidth (ΔHpp) = 0.57 mT) in the mushroom. Two-dimensional imaging of the sharp line using a 9 GHz EPR imager showed that the species were located in the cap and shortened stem portions of the mushroom. No other location of the species was found in the mushroom. However, radical locations and concentrations varied along the cap of the mushroom. The 9 GHz EPR imaging determined the exact location of stable paramagnetic species in the shiitake mushroom. Distilled water extracts of the pigmented cap surface and the inner cap of the mushroom showed similar antioxidant activities that reduced an aqueous solution of 0.1 mM 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl. The present results suggest that the antioxidant activities of the edible mushroom extracts are much weaker than those of ascorbic acid. Thus, CW EPR and EPR imaging revealed the location and distribution of stable paramagnetic species and the antioxidant activities in the shiitake mushroom for the first time.

  5. Simultaneous oscillations of twelve wavelengths around 1.3 μm in quasi-CW Nd:YAG laser (United States)

    Saha, Ardhendu; Debnath, Ruma; Hada, Digvijay Singh; Beda, Susheel Kumar


    In this work, a simple cavity configuration for simultaneous observation of twelve oscillating wavelengths around 1.3 μm in a quasi-CW side pumped Nd:YAG laser is proposed and demonstrated experimentally. The experiment has been studied in free running condition and by placing a position tunable Brewster plate within a linear cavity where new wavelengths viz. 1318.71 nm, 1338.14 nm, 1338.16 nm, 1338.18 nm, 1338.21 nm, 1338.23 nm, 1338.25 nm and 1338.27 nm have been observed. By introducing a Brewster plate within the cavity it is possible to maintain almost equal spectral contributions around 1318 nm and 1338 nm wavelength's regions at the highest as well as lowest pump power levels. The maximum average output power of 20 W and 13.87 W at slope efficiencies of 42.22% and 35.37% are obtained in both conditions respectively. In this work it is also possible to measure the average output powers around 1319 nm and 1338 nm regions simultaneously at different average pump powers. The experimental results indicate the higher and better stability of power contributions of observed oscillating wavelengths around 1.3 μm. The beam quality factor varies from 1.11 to 1.44 with the rise in average pump power simultaneously. The proposed work may enhance the application of 1.3 μm laser in spectroscopic field and tunable laser generation. Moreover, by difference frequency mixing within these closely spaced wavelengths this configuration may also be a good source of coherent THz generation.

  6. Determination of optical properties of turbid medium from relative interstitial CW radiance measurements using the incomplete P3 approximation. (United States)

    Liu, Lingling; Wan, Wenbo; Qin, Zhuanping; Zhang, Limin; Jiang, Jingying; Wang, Yihan; Gao, Feng; Zhao, Huijuan


    Interstitial determination of the tissue optical properties is important in biomedicine, especially for interstitial laser therapies. Continuous wave (CW) radiance techniques which examine light from multiple directions have been proposed as minimally invasive methods for determining the optical properties under an interstitial probe arrangement. However, both the fitting algorithm based on the P3 approximation and the analytical method based on the diffusion approximation (DA), which are currently used recovery algorithms, cannot extract the optical properties of tissue with low transport albedos accurately from radiance measurements. In this paper, we proposed an incomplete P3 approximation for the radiance, the P3in for short, which is the asymptotic part of the solution for the P3 approximation. The relative differences between the P3in and the P3 were within 0.48% over a wide range of clinically relevant optical properties for measurements at source detector separations (SDS) from 5 mm to 10 mm and angles from 0° to 160°. Based on the P3in, we developed an analytical method for extracting the optical properties directly using simple expressions constructed from the radiance measurements at only two SDSs and four angles. The developed recovery algorithm was verified by simulated and experimental radiance data. The results show that both the absorption and reduced scattering coefficients were recovered accurately with relative errors within 5.28% and 3.86%, respectively, from the simulated data and with relative errors within 10.82% and 10.67%, respectively, from the experimental data over a wide range of albedos from 0.5 to 0.99. Since the developed P3in-based radiance technique can obtain the optical properties rapidly from the measurements at only two SDSs and four angles, it is expected to be used for in vivo and in situ determination of the optical properties in online treatment planning during laser therapies.

  7. Room temperature CW and QCW operation of Ho:CaF2 laser pumped by Tm:fiber laser (United States)

    Jelínek, Michal; Cvrček, Jan; Kubeček, Václav; Zhao, Beibei; Ma, Weiwei; Jiang, Dapeng; Su, Liangbi


    Laser radiation in the wavelength range around 2 μm is required for its specific properties - it is very suitable for medical applications, remote sensing, or pumping of optical parametric oscillators to generate ultrafast pulses in the mid-IR region further exploited in nonlinear optics. Crystals as YLF, YAG, LLF, and GdVO4 doped by holmium were already investigated and found suitable for the tunable laser generation around 2.1 mμ. Only a few works are devoted to the laser operation of holmium-doped fluorides as CaF2. In this work, pulsed and continuous-wave laser operation of a modified- Bridgman-grown Ho:CaF2 active crystal at room temperature is reported. A commercial 50 W 1940 nm Tm-fiber laser was used to pump a laser oscillator based on a novel 10 mm long 0.5 at.% Ho:CaF2 active crystal placed in the Peltiercooled holder. In the pulsed regime (10 ms, 10 Hz), the laser slope efficiency of 53 % with respect to the absorbed pump power was achieved. The laser generated at the central wavelength of 2085 nm with the maximum mean output power of 365 mW corresponding to the power amplitude of 3.65 W. In the continuous wave regime, the maximum output power was 1.11 W with the slope efficiency of 41 % with respect to the absorbed pump power. To our best knowledge this is the first demonstration of this laser active material operating in the CW regime at room temperature. The tuning range over 60 nm from 2034 to 2094 nm was achieved using a birefringent filter showing the possibility to develop a mode-locked laser system generating pulses in the sub-picosecond range.

  8. A Comparison of Potential IM-CW Lidar Modulation Techniques for ASCENDS CO2 Column Measurements From Space (United States)

    Campbell, Joel F.; Lin, Bing; Nehrir, Amin R.; Harrison, F. Wallace; Obland, Michael D.; Ismail, Syed


    Global atmospheric carbon dioxide (CO2) measurements through the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) Decadal Survey recommended space mission are critical for improving our understanding of CO2 sources and sinks. IM-CW (Intensity Modulated Continuous Wave) lidar techniques are investigated as a means of facilitating CO2 measurements from space to meet the ASCENDS science requirements. In previous laboratory and flight experiments we have successfully used linear swept frequency modulation to discriminate surface lidar returns from intermediate aerosol and cloud contamination. Furthermore, high accuracy and precision ranging to the surface as well as to the top of intermediate clouds, which is a requirement for the inversion of the CO2 column-mixing ratio from the instrument optical depth measurements, has been demonstrated with the linear swept frequency modulation technique. We are concurrently investigating advanced techniques to help improve the auto-correlation properties of the transmitted waveform implemented through physical hardware to make cloud rejection more robust in special restricted scenarios. Several different carrier based modulation techniques are compared including orthogonal linear swept, orthogonal non-linear swept, and Binary Phase Shift Keying (BPSK). Techniques are investigated that reduce or eliminate sidelobes. These techniques have excellent auto-correlation properties while possessing a finite bandwidth (by way of a new cyclic digital filter), which will reduce bias error in the presence of multiple scatterers. Our analyses show that the studied modulation techniques can increase the accuracy of CO2 column measurements from space. A comparison of various properties such as signal to noise ratio (SNR) and time-bandwidth product are discussed.

  9. Use of Resting Cells of Native Screened Rhodotorula sp. CW03 in Biotransformation of Caffeine to Theophylline and Paraxanthine

    Directory of Open Access Journals (Sweden)

    M. Ashengroph


    Full Text Available Introduction & Objective: In recent years, microorganisms have been applied as biocatalysts for making pharmaceutically natural products. Microbial biotransformation of caffeine suggests a dual approach for biodegradation of toxic caffeine from polluted environments and a method for the production of medically and pharmaceutically valuable dimethylxanthines. The present work describes the identification of native yeasts capable of biotransformation of caffeine into theophylline and paraxanthine. Materials & Methods: In this experimental study fourteen yeast strains which were able to de-grade caffeine isolated based on their morphology were selected as biocatalysts for biotrans-formation of caffeine as a low-cost substrate to high value added dimethylxanthines such as theophylline and theobromine. The selected strains were characterized based on phenotypic and genetic tests. Screening was performed by Thin Layer Chromatography (TLC and High Performance Liquid Chromatography (HPLC analyses. Results: The results obtained using TLC and HPLC analyses suggest formation of two main metabolites of theophylline and paraxanthine from biotransformation of caffeine under resting cells of Rhodotorula sp. CW03 (GenBank accession number KF414531. The results showed that under resting cell conditions a maximum concentration of theophylline 380 mg/l (molar yield of 16.4% and paraxanthine 880 mg/l (molar yield of 37.9% were obtained after 72 h and 120 h of conversion time, respectively. Conclusion: In the current investigation, done for the first time in Iran, we describe the isola-tion and identification of yeast strains with caffeine degradation ability which can be proposed as safe and cost-effective biocatalysts in production of value added dimethylxanthines from caffeine as a low-cost substrate.(Sci J Hamadan Univ Med Sci 2015; 22 (2: 83-92

  10. QEPAS based ppb-level detection of CO and N2O using a high power CW DFB-QCL. (United States)

    Ma, Yufei; Lewicki, Rafał; Razeghi, Manijeh; Tittel, Frank K


    An ultra-sensitive and selective quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor platform was demonstrated for detection of carbon monoxide (CO) and nitrous oxide (N2O). This sensor used a state-of-the art 4.61 μm high power, continuous wave (CW), distributed feedback quantum cascade laser (DFB-QCL) operating at 10°C as the excitation source. For the R(6) CO absorption line, located at 2169.2 cm(-1), a minimum detection limit (MDL) of 1.5 parts per billion by volume (ppbv) at atmospheric pressure was achieved with a 1 sec acquisition time and the addition of 2.6% water vapor concentration in the analyzed gas mixture. For the N2O detection, a MDL of 23 ppbv was obtained at an optimum gas pressure of 100 Torr and with the same water vapor content of 2.6%. In both cases the presence of water vapor increases the detected CO and N2O QEPAS signal levels as a result of enhancing the vibrational-translational relaxation rate of both target gases. Allan deviation analyses were performed to investigate the long term performance of the CO and N2O QEPAS sensor systems. For the optimum data acquisition time of 500 sec a MDL of 340 pptv and 4 ppbv was obtained for CO and N2O detection, respectively. To demonstrate reliable and robust operation of the QEPAS sensor a continuous monitoring of atmospheric CO and N2O concentration levels for a period of 5 hours were performed.

  11. Impact of preformed donor-specific antibodies against HLA class I on kidney graft outcomes: Comparative analysis of exclusively anti-Cw vs anti-A and/or -B antibodies (United States)

    Santos, Sofia; Malheiro, Jorge; Tafulo, Sandra; Dias, Leonídio; Carmo, Rute; Sampaio, Susana; Costa, Marta; Campos, Andreia; Pedroso, Sofia; Almeida, Manuela; Martins, La Salete; Henriques, Castro; Cabrita, António


    AIM To analyze the clinical impact of preformed antiHLA-Cw vs antiHLA-A and/or -B donor-specific antibodies (DSA) in kidney transplantation. METHODS Retrospective study, comparing 12 patients transplanted with DSA exclusively antiHLA-Cw with 23 patients with preformed DSA antiHLA-A and/or B. RESULTS One year after transplantation there were no differences in terms of acute rejection between the two groups (3 and 6 cases, respectively in the DSA-Cw and the DSA-A-B groups; P = 1). At one year, eGFR was not significantly different between groups (median 59 mL/min in DSA-Cw group, compared to median 51 mL/min in DSA-A-B group, P = 0.192). Moreover, kidney graft survival was similar between groups at 5-years (100% in DSA-Cw group vs 91% in DSA-A-B group, P = 0.528). The sole independent predictor of antibody mediated rejection (AMR) incidence was DSA strength (HR = 1.07 per 1000 increase in MFI, P = 0.034). AMR was associated with shortened graft survival at 5-years, with 75% and 100% grafts surviving in patients with or without AMR, respectively (Log-rank P = 0.005). CONCLUSION Our data indicate that DSA-Cw are associated with an identical risk of AMR and impact on graft function in comparison with “classical” class I DSA. PMID:28058219

  12. Spoeg (CW5)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research


    Full Text Available deposition. The state of knowledge of the Spoeg is largely limited to the information obtained during the ECRU survey of 17/18 October 1980. This report provides historical information on Spoeg river but the flood history, in particular is lacking....

  13. Bitter (CW6)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research Unit, RCRU


    Full Text Available The nature of the Bitter surface sediments in the mouth region suggest that the river flows intermittently but probably only for short periods. This is to be expected from the nature of the rainfall and the small size of the catchment. Sediments...

  14. Verlorenvlei (CW13)

    CSIR Research Space (South Africa)

    Sinclair, SA


    Full Text Available in South Africa which provide the opportunity to combine conversation of the natural environment with the culture which developed in association with it. Furthermore, the rich archaeological resources of the region provide an insight into the pre...

  15. Swartlintjies (CW4)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research


    Full Text Available . The Swartlintjies is approximately 30 km long from the mouth up to where it splits into a number of unnamed tributaries. The lower part of the Estuary consists of a flat, wide sandy riverbed which indicates that substantial flooding and concomitant silt deposition...

  16. Ellipticus CW Illumination System (United States)


    3.2.1 Wormhole feed concept ................................................................................................5 3.2.2 Resistive Loading... Wormhole Feed concept for Ellipticus .....................................................................5 Figure 7. Ellipticus Resistive Loading...Illuminator at Patuxent River NAS. 3.2.1 Wormhole feed concept. The method chosen for driving the radiat- ing gap at the top of the antenna was what Dr

  17. Buffels (CW3)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research Unit, ECRU


    Full Text Available This report entails available historical information on Buffels estuary and abiotic and biotic characteristics found in the estuary are presented. Although the Buffels River has a relatively large catchment compared with most other major rivers...

  18. Olifants (CW10)

    CSIR Research Space (South Africa)

    Morant, PD


    Full Text Available In this report available historical information on Olifants estuary and abiotic and biotic characteristics found in the estuary are presented. The Olifants River system was explored early in the colonization of the Cape by European settlers...

  19. Holgat (CW2)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research Unit, ECRU


    Full Text Available The Holgat is not an estuary in the true sense, due to a combination of factors. Although the catchment has an area of 1500 km2, the Holgat last flowed in 1925. The main reason for this appears to be the low rainfall in the catchment and the dune...

  20. Hout Bay (CW27)

    CSIR Research Space (South Africa)

    Grindley, SA


    Full Text Available convenient and, in the short-term, cheap conduit for stormwater from new development should be halted. More effective means of conducting stormwater to the sea from new developments on both sides of the valley should be investigated. To allow new developments...

  1. Groen (CW7)

    CSIR Research Space (South Africa)

    Estuarine and Coastal


    Full Text Available The state of knowledge of the Groen is poor. The area, being remote, has received little attention in the past and the bulk of information in this report originates from the Estuarine and Coastal Research Unit (ECRU) survey. Although the Groen flows...

  2. Carbonated water (CW) process waste reuse for ammonium-uranyl-carbonate (AUC) production and its gains on the environmental, economic and social aspects

    Energy Technology Data Exchange (ETDEWEB)

    Carnaval, Joao Paulo R.; Santos, Rafael D. dos; Barbosa, Rodrigo A.; Lauer, Sergio, E-mail:, E-mail:, E-mail:, E-mail: [Industias Nucleares do Brasil S.A. (INB), Resende, RJ (Brazil)


    In the INB nuclear fuel cycle, the pellets production is based on UO{sub 2} powder made by AUC (Ammonium-Uranyl-Carbonate) route. AUC formation occurs by fluidising of UF{sub 6}, NH{sub 3} and CO{sub 2} in a vase containing usually pure water, and this exothermal reaction has AUC as direct product. The mass formed is filtered, washed with CW, washed again with methano solution, dried with air and conducted to the fluidized bed furnace, to be converted to UO{sub 2} powder. At this point, the dried AUC decompounds to UO{sub 3}, NH{sub 3} and C0{sub 2}, these 2 gases are absorbed at the gases washer, formin go the carbonated water (CW), whit is basically a (NH{sub 4}){sub 2}CO{sub 3} solution. The UO{sub 2+x} is reduced and stabilized to UO{sub 2} powder, which is conducted to pellets production. During the process, a considerable amount of this aqueous waste is generated and goes for effluent treatment. After that, the solution is sent for spray-dryer for power formation, and stock. This treatment demands equipment, energy and time, representing considerable costs of the company beyond the human risks involved on the drying step. The purpose of this work is to present a study of the carbonated water use as substitute of pure water in the AUC formation step. At this point, tests were made varying the CW loads for the AUC precipitation, and the control was made by the UO{sub 2} powder properties. The carbonated water used for AUC precipitation has been tested at several levels and the results has demonstrated full viability to become a definitive process step (INB, Resende site). It has been demonstrated the great resources economy caused by the waste reuse and the guarantee product quality. This represents such an environmental gain and also economic and social aspects got improved. (author)

  3. Soil Aquifer Treatment (SAT) and Constructed Wetlands (CW) Applications for Nutrients and Organic Micropollutants (OMPs) Attenuation Using Primary and Secondary Wastewater Effluents

    KAUST Repository

    Hamadeh, Ahmed F.


    Constructed wetlands (CW) and soil aquifer treatment (SAT) represent natural wastewater treatment systems (NWTSs). The high costs of conventional wastewater treatment techniques encourage more studies to investigate lower cost treatment methods which make these appropriate for developing and also in developed countries. The main objective of this research was to investigate the removals of nutrients and organic micropollutants (OMPs) through SAT, CW and the CW-SAT hybrid system. CWs are an efficient technology to purify and remove different nutrients as well as OMPs from wastewater. They removed most of the dissolved organic matter (DOC), total nitrogen (TN), ammonium and phosphate. Furthermore, CWs aeration could be used as one of the alternatives to reduce CWs footprint by around 10%. The vegetation in CWs plays an essential role in the treatment especially for nitrogen and phosphate removals, it is responsible for the removal of 15%, 55%, 38%, and 22% for TN, dissolved organic nitrogen (DON), nitrate and phosphate, respectively. CWs achieved a very high removal for some OMPs; they attenuated acetaminophen, caffeine, fluoxetine and trimethoprim (>90%) under different redox conditions. Moreover, it was found that increasing temperature (up to 36 C) could enhance the removals of atenolol, caffeine, DEET and trimethoprim by 17%, 14%, 28% and 45%, respectively. On the other hand, some OMPs, were found to be removed by vegetation such as: acetaminophen, caffeine, fluoxetine, sulfamethoxazole, and trimethoprim. Moreover, atenolol, caffeine, fluoxetine and trimethoprim, showed high removal (>80%) through SAT system. It was also found that, temperature increasing and using primary instead of secondary effluent could enhance the removal of some OMPs. The CWs performance study showed that these systems are adapted to the prevailing extreme arid conditions and the average percent removals are about, 88%, 96%, 98%, 98% and 92%, for COD, BOD and TSS, ammonium and phosphate

  4. 28 W CW linearly polarized single mode all-fiber thulium-doped fiber laser operating at 1.95 μm (United States)

    Wang, Jiachen; Yeom, Dong-il; Lee, Sang Bae; Lee, Kwanil


    An all-fiber type, CW, linearly polarized thulium-doped fiber laser is reported. Highly linear polarization was achieved by a special management of fiber Bragg gratings, which performs as the laser cavity reflectors. The laser generated 28 W signal output at 1949 nm with a slope efficiency of 47.3%. The polarization extinction ratio of the laser was measured to be around 20 dB. The beam quality of the laser was near diffraction-limited, with M2 of 1.1. The laser's output features make it to be a potential light source for some important applications such as for pumping holmium-doped solid state lasers.

  5. Bone marrow transplantation with unrelated donors: what is the probability of identifying an HLA-A/B/Cw/DRB1/B3/B5/DQB1-matched donor? (United States)

    Tiercy, J M; Bujan-Lose, M; Chapuis, B; Gratwohl, A; Gmür, J; Seger, R; Kern, M; Morell, A; Roosnek, E


    Patients transplanted with marrow from an HLA-ABDR serologically matched unrelated donor suffer from more post-transplant complications than those who are transplanted with marrow from an HLA-identical sibling. This is most likely due to either HLA-ABDR incompatibilities not resolved by standard techniques and/or HLA polymorphisms not tested for by routine tissue typing (HLA-Cw,-DQ). By resolving these incompatibilities by molecular techniques combined with the in vitro cytotoxic T lymphocyte precursor frequency (CTLpf) test, we have shown that a high degree of HLA compatibility is associated with increased patient survival. However, higher requirements for HLA matching decrease the number of available donors. We have estimated the probability of finding an HLA-A/B/Cw/DRB1/DRB3/DRB5/DQB1 compatible donor based on 104 consecutive unrelated bone marrow donor searches initiated between January 1995 and December 1997, with December 1998 as the endpoint. For 96 patients (92.3%), one or more ABDR-identical donors were listed in the Bone Marrow Donor Worldwide Registry (BMDW). After contacting the registries, we obtained at least one (mean, 5.36; range, 1-20; total, 461) blood sample for 86 patients. A highly compatible donor was identified for 33/86 patients (38.4%), after testing an average number of 4.5 donors/patients (range, 1-13). However, by accepting an HLA-DRB3 or -DQB1 or -Cw incompatibility, this number would be as high as 68.6%. Approximately half of the patients (n = 40) for whom a search had been initiated have been transplanted: 22 patients with a perfectly matched donor, 15 patients with an HLA-DRB3 or -DQB1 or -Cw mismatch and three with other mismatches. The average time needed to identify the most compatible donor was 4 months. Extremely long searches seemed to be less useful, because after testing the first seven, a more compatible donor was seldom found. These results show that even when requirements for compatibility are high, the chances of finding

  6. Further Characterization of 394-GHz Gyrotron FU CW GII with Additional PID Control System for 600-MHz DNP-SSNMR Spectroscopy (United States)

    Ueda, Keisuke; Matsuki, Yoh; Fujiwara, Toshimichi; Tatematsu, Yoshinori; Ogawa, Isamu; Idehara, Toshitaka


    A 394-GHz gyrotron, FU CW GII, has been designed at the University of Fukui, Japan, for dynamic nuclear polarization (DNP)-enhanced solid-state nuclear magnetic resonance (SSNMR) experiments at 600-MHz 1H resonant frequency. After installation at the Institute for Protein Research (IPR), Osaka University, Japan, a PID feedback control system was equipped to regulate the electron gun heater current for stabilization of the electron beam current, which ultimately achieved stabilization of output power when operating in continuous wave (CW) mode. During exploration to further optimize operating conditions, a continuous tuning bandwidth of approximately 1 GHz was observed by varying the operating voltage at a fixed magnetic field. In the frequency range required for positive DNP enhancement, the output power was improved by increasing the magnetic field and the operating voltage from their initial operational settings. In addition, fine tuning of output frequency by varying the cavity cooling water temperature was demonstrated. These operating conditions and ancillary enhancements are expected to contribute to further enhancement of SSNMR signal.

  7. Monitoring Tumor Targeting and Treatment Effects of IRDye 800CW and GX1-Conjugated Polylactic Acid Nanoparticles Encapsulating Endostar on Glioma by Optical Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Yaqian Li


    Full Text Available Molecular imaging used in cancer diagnosis and therapeutic response monitoring is important for glioblastoma (GBM research. Antiangiogenic therapy currently is one of the emerging approaches for GBM treatment. In this study, a multifunctional nanoparticle was fabricated that can facilitate the fluorescence imaging of tumor and deliver a therapeutic agent to the tumor region in vivo and therefore possesses broad application in cancer diagnosis and treatment. This particle was polylactic acid (PLA nanoparticles encapsulating Endostar, which was further conjugated with GX1 peptide and the near-infrared (NIR dye IRDye 800CW (IGPNE. We demonstrated noninvasive angiogenesis targeting and therapy of IGPNE on U87MG xenografts in vivo using dual-modality optical molecular imaging including NIR fluorescence molecular imaging (FMI and bioluminescence imaging (BLI. The NIR FMI results demonstrated that IGPNE had more accumulation to the tumor site compared to free IRDye 800CW. To further evaluate the antitumor treatment efficacy of IGPNE, BLI and immunohistochemistry analysis were performed on tumor-bearing mice. With the aid of molecular imaging, the results confirmed that IGPNE enhanced antitumor treatment efficacy compared to free Endostar. In conclusion, IGPNE realizes real-time imaging of U87MG tumors and improves the antiangiogenic therapeutic efficacy in vivo.

  8. Room-temperature CW operation of a nitride-based vertical-cavity surface-emitting laser using thick GaInN quantum wells (United States)

    Furuta, Takashi; Matsui, Kenjo; Horikawa, Kosuke; Ikeyama, Kazuki; Kozuka, Yugo; Yoshida, Shotaro; Akagi, Takanobu; Takeuchi, Tetsuya; Kamiyama, Satoshi; Iwaya, Motoaki; Akasaki, Isamu


    We demonstrated a room-temperature (RT) continuous-wave (CW) operation of a GaN-based vertical-cavity surface-emitting laser (VCSEL) using a thick GaInN quantum well (QW) active region and an AlInN/GaN distributed Bragg reflector. We first investigated the following two characteristics of a 6 nm GaInN 5 QWs active region in light-emitting diode (LED) structures. The light output power at a high current density (∼10 kA/cm2) from the 6 nm GaInN 5 QWs was the same or even higher than that from standard 3 nm 5 QWs. In addition, we found that hole injection into the farthest QW from a p-layer was sufficient. We then demonstrated a GaN-based VCSEL with the 6 nm 5 QWs, resulting in the optical confinement factor of 3.5%. The threshold current density under CW operation at RT was 7.5 kA/cm2 with a narrow (0.4 nm) emission spectrum of 413.5 nm peak wavelength.

  9. Measurements of carbon monoxide mixing ratios in Houston using a compact high-power CW DFB-QCL-based QEPAS sensor (United States)

    Stefański, Przemysław; Lewicki, Rafał; Sanchez, Nancy P.; Tarka, Jan; Griffin, Robert J.; Razeghi, Manijeh; Tittel, Frank K.


    Measurements of carbon monoxide (CO) mixing ratios in Houston, Texas, during the period from May 16, 2013 to May 28, 2013 were performed using a sensitive, selective, compact, and portable quartz-enhanced photoacoustic spectroscopy (QEPAS)-based CO sensor employing a high-power continuous wave (CW) distributed feedback quantum cascade laser (DFB-QCL). The minimum detectable CO concentration was 3 ppbv for the strong, interference-free R(6) absorption line at 2,169.2 cm-1 and a 5 s data acquisition time. The average CO concentration during the measurement period was 299.1 ± 81.4 ppb with observed minimum and maximum values of 210.5 and 4,307.9 ppb, respectively. A commercially available electrochemical sensor was employed in-line for simultaneous measurements to confirm the response of the CW DFB-QCL-based QEPAS sensor to variations of the CO mixing ratios. Moderate agreement (R 2 = 0.7) was found between both sets of CO measurements.

  10. Manufacture of IRDye800CW-coupled Fe3O4 nanoparticles and their applications in cell labeling and in vivo imaging

    Directory of Open Access Journals (Sweden)

    Chen Zhongping


    Full Text Available Abstract Background In recent years, near-infrared fluorescence (NIRF-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area. Results This study manufactured 12-nm DMSA-coated Fe3O4 nanoparticles labeled with a near-infrared fluorophore, IRDye800CW (excitation/emission, 774/789 nm, to investigate their applicability in cell labeling and in vivo imaging. The mouse macrophage RAW264.7 was labeled with IRDye800CW-labeled Fe3O4 nanoparticles at concentrations of 20, 30, 40, 50, 60, 80 and 100 μg/ml for 24 h. The results revealed that the cells were efficiently labeled by the nanoparticles, without any significant effect on cell viability. The nanoparticles were injected into the mouse via the tail vein, at dosages of 2 or 5 mg/kg body weight, and the mouse was discontinuously imaged for 24 h. The results demonstrated that the nanoparticles gradually accumulated in liver and kidney regions following injection, reaching maximum concentrations at 6 h post-injection, following which they were gradually removed from these regions. After tracing the nanoparticles throughout the body it was revealed that they mainly distributed in three organs, the liver, spleen and kidney. Real-time live-body imaging effectively reported the dynamic

  11. Feasibility of in vivo three-dimensional T 2* mapping using dicarboxy-PROXYL and CW-EPR-based single-point imaging. (United States)

    Kubota, Harue; Komarov, Denis A; Yasui, Hironobu; Matsumoto, Shingo; Inanami, Osamu; Kirilyuk, Igor A; Khramtsov, Valery V; Hirata, Hiroshi


    The aim of this study was to demonstrate the feasibility of in vivo three-dimensional (3D) relaxation time T 2* mapping of a dicarboxy-PROXYL radical using continuous-wave electron paramagnetic resonance (CW-EPR) imaging. Isotopically substituted dicarboxy-PROXYL radicals, 3,4-dicarboxy-2,2,5,5-tetra(2H3)methylpyrrolidin-(3,4-2H2)-(1-15N)-1-oxyl (2H,15N-DCP) and 3,4-dicarboxy-2,2,5,5-tetra(2H3)methylpyrrolidin-(3,4-2H2)-1-oxyl (2H-DCP), were used in the study. A clonogenic cell survival assay was performed with the 2H-DCP radical using squamous cell carcinoma (SCC VII) cells. The time course of EPR signal intensities of intravenously injected 2H,15N-DCP and 2H-DCP radicals were determined in tumor-bearing hind legs of mice (C3H/HeJ, male, n = 5). CW-EPR-based single-point imaging (SPI) was performed for 3D T 2* mapping. 2H-DCP radical did not exhibit cytotoxicity at concentrations below 10 mM. The in vivo half-life of 2H,15N-DCP in tumor tissues was 24.7 ± 2.9 min (mean ± standard deviation [SD], n = 5). The in vivo time course of the EPR signal intensity of the 2H,15N-DCP radical showed a plateau of 10.2 ± 1.2 min (mean ± SD) where the EPR signal intensity remained at more than 90% of the maximum intensity. During the plateau, in vivo 3D T 2* maps with 2H,15N-DCP were obtained from tumor-bearing hind legs, with a total acquisition time of 7.5 min. EPR signals of 2H,15N-DCP persisted long enough after bolus intravenous injection to conduct in vivo 3D T 2* mapping with CW-EPR-based SPI.

  12. Measurements of linestrengths, N2-, Ar-, He- and self-broadening coefficients of acetylene in the ν4+ν5 combination band using a cw quantum cascade laser

    KAUST Repository

    Sajid, Muhammad Bilal


    Linestrengths, N2-, Ar-, He- and self-broadening coefficients of acetylene have been measured at 296K in the P branch of the ν4+ν5 combination band for 25 rotational transitions. The effect of gas temperature is studied over 296-683K for five transitions to allow the determination of the temperature dependent exponent n for N2- and Ar-broadening coefficients. These measurements were performed using a continuous-wave quantum cascade laser (cw-QCL) operating over 1253-1310cm-1. Spectroscopic parameters were obtained by fitting absorption spectra using Voigt, Galatry and Rautian profiles. Linestrength and broadening results are compared with previous studies available in literature for the ν4+ν5 combination band and other vibrational bands of acetylene. © 2014 Elsevier Ltd.

  13. Measurements of linestrengths, N2-, Ar-, He- and self-broadening coefficients of acetylene in the ν4+ν5 combination band using a cw quantum cascade laser (United States)

    Sajid, Muhammad Bilal; Es-sebbar, Et-touhami; Farooq, Aamir


    Linestrengths, N2-, Ar-, He- and self-broadening coefficients of acetylene have been measured at 296 K in the P branch of the ν4+ν5 combination band for 25 rotational transitions. The effect of gas temperature is studied over 296-683 K for five transitions to allow the determination of the temperature dependent exponent n for N2- and Ar-broadening coefficients. These measurements were performed using a continuous-wave quantum cascade laser (cw-QCL) operating over 1253-1310 cm-1. Spectroscopic parameters were obtained by fitting absorption spectra using Voigt, Galatry and Rautian profiles. Linestrength and broadening results are compared with previous studies available in literature for the ν4+ν5 combination band and other vibrational bands of acetylene.

  14. Up to 30 mW of broadly tunable CW green-to-orange light, based on sum-frequency mixing of Cr4+:forsterite and Nd:YVO4 lasers

    DEFF Research Database (Denmark)

    Mortensen, Jesper Liltorp; McWilliam, Allan; G. Leburn, Christopher


    Efficient generation of continuous-wave (CW) tunable light in the yellow region is reported. The method is based on sum-frequency mixing of a tunable Cr4+:forsterite laser with a Nd:YVO4 laser. A periodically poled lithium niobate crystal was placed intra-cavity in a Nd:YVO4 laser, and the Cr4...

  15. Up to 30 mW of broadly tunable CW green-to-orange light, based on sum-frequency mixing of Cr4+:forsterite and Nd:YVO4 lasers

    DEFF Research Database (Denmark)

    Mortensen, Jesper Liltorp; McWilliam, Alan; Leburn, Christopher G


    +:forsterite laser was single-passed through the non-linear media. With this setup, it was possible to generate up to 3 mW of yellow light smoothly tunable from 573 to 587 nm. This is the highest output demonstrated to date for a tunable diode pumped solid-state CW laser in this wavelength region. The ways...

  16. Comportamiento en fluencia de un material compuesto de matriz metálica Al6061-15 vol % SiCw pulvimetalúrgico

    Directory of Open Access Journals (Sweden)

    González-Doncel, G.


    Full Text Available The creep behavior of a powder metallurgy (PM Al6061-15 vol % SiCw metal matrix composite has been studied. This behavior has been compared to that of 6061Al cast alloy and 6061Al PM alloy. The creep response of the PM unreinforced alloy is better than that of the cast 6061Al alloy. Similarly, the behavior of the composite is better than that of the PM unreinforced alloy. Two microstructural factors have been considered the responsible ones of this improvement. The first one is the dispersion of Al2O3 oxide particles of nanometric scale. The second one, is the presence of the SiC whisker reinforcement of micrometric scale. Despite the similar strengthening effect, the intrinsic nature of the reinforcing mechanism is, however, different for each type of particle due to the different microstructural scale.Se ha realizado un estudio de las propiedades en fluencia del material compuesto pulvimetalúrgico Al6061-15 vol % SiCw. Su comportamiento se ha comparado con el de la aleación Al6061 pulvimetalúrgica y la aleación Al6061 de colada. El comportamiento del material pulvimetalúrgico sin reforzar mejora respecto al del material de colada. Al mismo tiempo, el del material compuesto mejora respecto al comportamiento del material pulvimetalúrgico sin reforzar. Se consideran dos factores microestructurales como los principales responsables de la mejora de las propiedades en fluencia de este material compuesto. Por un lado, las partículas de Al2O3 de tamaño nanométrico y, por otro, las partículas de fibra corta cerámicas de SiC de tamaño micrométrico. Aunque ambos tipos de partículas dan lugar a un efecto de refuerzo similar, los mecanismos intrínsecos asociados a la presencia de estas partículas tienen una naturaleza diferente debido a la diferencia en la escala microestructural.

  17. A tunable general purpose Q-band resonator for CW and pulse EPR/ENDOR experiments with large sample access and optical excitation (United States)

    Reijerse, Edward; Lendzian, Friedhelm; Isaacson, Roger; Lubitz, Wolfgang


    We describe a frequency tunable Q-band cavity (34 GHz) designed for CW and pulse Electron Paramagnetic Resonance (EPR) as well as Electron Nuclear Double Resonance (ENDOR) and Electron Electron Double Resonance (ELDOR) experiments. The TE 011 cylindrical resonator is machined either from brass or from graphite (which is subsequently gold plated), to improve the penetration of the 100 kHz field modulation signal. The (self-supporting) ENDOR coil consists of four 0.8 mm silver posts at 2.67 mm distance from the cavity center axis, penetrating through the plunger heads. It is very robust and immune to mechanical vibrations. The coil is electrically shielded to enable CW ENDOR experiments with high RF power (500 W). The top plunger of the cavity is movable and allows a frequency tuning of ±2 GHz. In our setup the standard operation frequency is 34.0 GHz. The microwaves are coupled into the resonator through an iris in the cylinder wall and matching is accomplished by a sliding short in the coupling waveguide. Optical excitation of the sample is enabled through slits in the cavity wall (transmission ˜60%). The resonator accepts 3 mm o.d. sample tubes. This leads to a favorable sensitivity especially for pulse EPR experiments of low concentration biological samples. The probehead dimensions are compatible with that of Bruker flexline Q-band resonators and it fits perfectly into an Oxford CF935 Helium flow cryostat (4-300 K). It is demonstrated that, due to the relatively large active sample volume (20-30 μl), the described resonator has superior concentration sensitivity as compared to commercial pulse Q-band resonators. The quality factor ( Q L) of the resonator can be varied between 2600 (critical coupling) and 1300 (over-coupling). The shortest achieved π/2-pulse durations are 20 ns using a 3 W microwave amplifier. ENDOR (RF) π-pulses of 20 μs ( 1H @ 51 MHz) were obtained for a 300 W amplifier and 7 μs using a 2500 W amplifier. Selected applications of the

  18. Design and construction of a 500 KW CW, 400 MHz klystron to be used as RF power source for LHC/RF component tests

    CERN Document Server

    Frischholz, Hans; Pearson, C


    A 500 kW cw klystron operating at 400 MHz was developed and constructed jointly by CERN and SLAC for use as a high-power source at CERN for testing LHC/RF components such as circulators, RF absorbers and superconducting cavities with their input couplers. The design is a modification of the 353 MHz SLAC PEP-I klystron. More than 80% of the original PEP-I tube parts could thus be incorporated in the LHC test klystron which resulted in lower engineering costs as well as reduced development and construction time. The physical length between cathode plane and upper pole plate was kept unchanged so that a PEP-I tube focusing solenoid, available at CERN, could be re-used. With the aid of the klystron simulation codes JPNDISK and CONDOR, the design of the LHC tube was accomplished, which resulted in a tube with noticeably higher efficiency than its predecessor, the PEP-I klystron. The integrated cavities were redesigned using SUPERFISH and the output coupling circuit, which also required redesigning, was done with t...

  19. Theory of CW lidar aerosol backscatter measurements and development of a 2.1 microns solid-state pulsed laser radar for aerosol backscatter profiling (United States)

    Kavaya, Michael J.; Henderson, Sammy W.; Frehlich, R. G.


    The performance and calibration of a focused, continuous wave, coherent detection CO2 lidar operated for the measurement of atmospheric backscatter coefficient, B(m), was examined. This instrument functions by transmitting infrared (10 micron) light into the atmosphere and collecting the light which is scattered in the rearward direction. Two distinct modes of operation were considered. In volume mode, the scattered light energy from many aerosols is detected simultaneously, whereas in the single particle mode (SPM), the scattered light energy from a single aerosol is detected. The analysis considered possible sources of error for each of these two cases, and also considered the conditions where each technique would have superior performance. The analysis showed that, within reasonable assumptions, the value of B(m) could be accurately measured by either the VM or the SPM method. The understanding of the theory developed during the analysis was also applied to a pulsed CO2 lidar. Preliminary results of field testing of a solid state 2 micron lidar using a CW oscillator is included.

  20. Design-support and performance estimation using HYDRUS/CW2D: a horizontal flow constructed wetland for polishing SBR effluent. (United States)

    Pálfy, Tamás Gábor; Gribovszki, Zoltán; Langergraber, Günter


    The 4,000 PE (700 m(3)/d) wastewater treatment plant at Balf, Hungary was based on sequencing batch reactor technology with phosphorus precipitation as the tertiary step. Its effluent met quality thresholds on average, with above-threshold peaks mainly in winter. The HYDRUS/CW2D model package (PC Progress s.r.o.) was used to simulate the treatment performance of a horizontal flow constructed wetland for polishing effluent. The goal of this study was to provide design-supportive information about the suitability of the proposed wetland and to prove the applicability of the computational tool used to gain that information. The simulations showed that the wetland with the proposed layout could not tackle peaks in NH4-N. Other effluent thresholds could be met, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total nitrogen, total inorganic nitrogen and total phosphorus. The tool was unable to simulate COD and BOD5 removal in periods when the electron acceptors were depleted because anaerobic processes are not modelled. Using a tool of such complexity for designing carries excessive work demands and involves many uncertainties. The simulation study highlighted that the model used could still facilitate the design of an effective system by showing the weaknesses of a test scenario as it was demonstrated.

  1. The microalga Chlamydomonas reinhardtii CW-15 as a solar cell for hydrogen peroxide photoproduction. Comparison between free and immobilized cells and thylakoids for energy conversion efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, W.; Galvan, F.; Rosa, F.F. de la [Instituto de Bioquimica Vegetal y Fotosintesis, Universidad de Sevilla y CSIC, Sevilla (Spain)


    Immobilized cells and thylakoid vesicles of the microalga Chlamydomonas reinhardtii CW-15 have been developed as a solar cell because of their capabilities of producing hydrogen peroxide. This compound is an efficient and clean fuel used for rocket propulsion, motors and for heating. Hydrogen peroxide is produced by the photosystem in a catalyst cycle in which a redox mediator (methyl viologen) is reduced by electrons obtained from water by the photosynthetic apparatus of the microalga and it is re-oxidized by the oxygen dissolved in the solution. The photoproduction has been investigated using a discontinuous system with whole cells, or thylakoid vesicles, free or immobilized on alginate. The stimulation by azide as an inhibitor of catalase has also been analyzed. Under determined optimum conditions, the photoproduction by Ca-alginate entrapped cells, with a rate of 33 {mu}mol H{sub 2}O{sub 2}/mg Chl.h, was maintained for several hours with an energy conversion efficiency of 0.25%

  2. Endoscopic endonasal transsphenoidal exposure of circle of Willis (CW); can it be applied in vascular neurosurgery in the near future? A cadaveric study of 26 cases. (United States)

    Chowdhury, Forhad H; Haque, Mohammod R; Kawsar, Khandkar A; Ara, Shamim; Mohammod, Quazi Deen; Sarker, Mainul H; Goel, Atul H


    Endonasal transsphenoidal approaches are getting rapidly popular in removing many midline skullbase lesions from crista galli to foramen magnum. For safe removal of these lesions, familiarity with endoscopic endonasal anatomy of circle of Willis is very important. Furthermore, for safe development of this approach in vascular neurosurgery in the near future, endoscopic endonasal exposure of circle of Willis is a fundamental step. The goals in this study were to dissect the circle of Willis completely through the endoscopic endonasal approach and to become more familiar with the views and skills associated with the technique by using fresh cadaveric specimens. After obtaining ethical clearance, 26 fresh cadaver heads were used without any preparation. Using a neuroendoscope, complete exposure of the circle of Willis was done endonasaly, and various observations including relation of circle of Willis was recorded. Complete exposure of the circle of Willis was made through an endonasal approach in all cases without injuring surrounding structures. Endoscopic endonasal extended transsphenoidal exposure of CW can make the surgeon more efficient in removing midline skullbase lesions with safe handling of different parts of circle of Willis and it may help in development of endonasal endoscopic vascular neurosurgery in the near future.

  3. Optical features of Ca{sub 4}NdO(BO{sub 3}){sub 3}:Yb single crystals under CW laser illumination

    Energy Technology Data Exchange (ETDEWEB)

    Wojciechowski, A. [Electrical Engineering Department, Czestochowa Technological University, Armii Krajowej Av. 17/19, Czestochowa (Poland); Swirkowicz, M.; Karas, A. [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); Jaroszewicz, L.R.; Majchrowski, A. [Institute of Applied Physics, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw (Poland); Gondek, E. [Institute of Physics, Cracow University of Technology, Podchorazych St. 1, Cracow 30-084 (Poland); Ozga, K. [Public Health, Czestochowa Technological University, Armii Krajowej Av. 36B, 42-200 Czestochowa (Poland); Kityk, I.V., E-mail: ikityk@el.pcz.czest.p [Electrical Engineering Department, Czestochowa Technological University, Armii Krajowej Av. 17/19, Czestochowa (Poland)


    Optical treatment of Ca{sub 4}NdO(BO{sub 3}){sub 3}:Yb under continuous laser illumination at different wavelengths led to substantial changes of optical absorption and optical second harmonic generation. The treatment was performed successively by infrared (780 nm), red (650 nm), green (532 nm) and blue (405 nm) laser wavelengths with powers varying within the 200-400 mW range. We demonstrated enhancement of the optical second harmonic generation in the Ca{sub 4}NdO(BO{sub 3}){sub 3}:Yb (1.9% in weighting unit) crystals under the influence of the green cw laser at 532 nm. The principal changes were observed after 15 min of the treatment. A correlation between the occurrence of the hyperfine structure in the absorption spectra and the enhancement of the optical second harmonic generation was found. The additional treatment by the blue laser led to disappearance of appeared photo-induced changes of absorption and decrease of the optical second harmonic generation. It is principal that the effect is non-reversible in time and it does not depend on the photo-inducing light polarization. The principal origin of the observed photo-induced optical second harmonic generation is photo-polarization of the particular rare earth localized levels and formation of the stable polarized states due to the presence of Yb ions, playing crucial role. No such effects were observed in pure Ca{sub 4}NdO(BO{sub 3}){sub 3}.

  4. Validation of an SPME method, using PDMS, PA, PDMS-DVB, and CW-DVB SPME fiber coatings, for analysis of organophosphorus insecticides in natural waters. (United States)

    Lambropoulou, D A; Sakkas, V A; Albanis, T A


    Solid-phase microextraction (SPME) has been optimized and applied to the determination of the organophosphorus insecticides diazinon, dichlofenthion, parathion methyl, malathion, fenitrothion, fenthion, parathion ethyl, bromophos methyl, bromophos ethyl, and ethion in natural waters. Four types of SPME fiber coated with different stationary phases (PDMS, PA, PDMS-DVB, and CW-DVB) were used to examine their extraction efficiencies for the compounds tested. Conditions that might affect the SPME procedure, such as extraction time and salt content, were investigated to determine the analytical performance of these fiber coatings for organophosphorus insecticides. The optimized procedure was applied to natural waters - tap, sea, river, and lake water - spiked in the concentration range 0.5 to 50 micro g L(-1) to obtain the analytical characteristics. Recoveries were relatively high - >80% for all types of aqueous sample matrix - and the calibration plots were reproducible and linear (R(2)>0.982) for all analytes with all the fibers tested. The limits of detection ranged from 2 to 90 ng L(-1), depending on the detector and the compound investigated, with relative standard deviations in the range 3-15% at all the concentration levels tested. The SPME partition coefficients (K(f)) of the organophosphorus insecticides were calculated experimentally for all the polymer coatings. The effect of organic matter such as humic acids on extraction efficiency was also studied. The analytical performance of the SPME procedure using all the fibers in the tested natural waters proved effective for the compounds.

  5. Investigation of the C2H2-CO2 van der Waals complex in the overtone range using cw cavity ring-down spectroscopy (United States)

    Lauzin, C.; Didriche, K.; Liévin, J.; Herman, M.; Perrin, A.


    A slit nozzle supersonic expansion containing acetylene [492 SCCM (SCCM denotes cubic centimeter per minute at STP)] and carbon dioxide (740 SCCM) seeded into Ar (837 SCCM) is investigated using cw-cavity ring-down spectroscopy, in the 1.5 μm range. The C2H2-CO2 van der Waals complex is observed around the ν1+ν3 acetylenic band. The rotational temperature is estimated to be close to 60 K from the comparison between observed and simulated spectra. The analysis of the main, perturbed B-type band centered near 6 549.280 cm-1, is performed. It is attributed to a dimer with the known planar, C2v geometry. The present overtone data, involving ground state levels with higher J /K states (J ≤35 and Ka≤20) than previously reported, are combined to 3 μm data [D. G. Prichard, R. N. Nandi, J. S. Muenter, and B. J. Howard, J. Chem. Phys. 89, 1245 (1988); Z. S. Huang and R. E. Miller, Chem. Phys. 132, 185 (1989)] to determine improved ground state parameters. The major perturbations affecting the upper state are accounted for through C-type Coriolis resonances involving one dark state, whose symmetry must therefore be A1. Upper state constants are obtained for the bright and dark states. The dependence upon vibrational excitation is demonstrated to arise from excitation in the acetylene unit, only, for the former, but cannot be unravelled for the latter.

  6. Topotactic changes on η-Mo{sub 4}O{sub 11} caused by biased atomic force microscope tip and cw-laser

    Energy Technology Data Exchange (ETDEWEB)

    Borovšak, Miloš, E-mail: [Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Faculty for Mathematics and Physics, Jadranska ulica 19, 1000 Ljubljana (Slovenia); Šutar, Petra; Goreshnik, Evgeny [Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Mihailovic, Dragan [Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); International Postgraduate School Jožef Stefan, Jamova cesta 39, 1000 Ljubljana (Slovenia)


    Highlights: • We report influencing electronic properties of η-Mo{sub 4}O{sub 11}. • With the biased AFM tip we induce the surface potential changes on η-Mo{sub 4}O{sub 11}. • We used cw-laser to induced similar effect on surface potential on η-Mo{sub 4}O{sub 11}. • We do not influence the surface and topography of the samples. • No change in topography of samples indicates the topotactic transformation. - Abstract: We present topotactic changes on Mo{sub 4}O{sub 11} crystals induced by a biased atomic force microscope tip and continuous laser. The transformation does not change the topography of the samples, while the surface potential shows remarkable changes on areas where the biased AFM tip was applied. No structural changes were observed by Raman spectroscopy, but AFM scans revealed changes to surface potential due to laser illumination. The observed phenomenon could be potentially useful for memristive memory devices considering the fact that properties of other molybdenum oxides vary from metallic to insulators.

  7. DNA strand breaks are not induced in human cells exposed to 2.1425 GHz band CW and W-CDMA modulated radiofrequency fields allocated to mobile radio base stations. (United States)

    Sakuma, N; Komatsubara, Y; Takeda, H; Hirose, H; Sekijima, M; Nojima, T; Miyakoshi, J


    We conducted a large-scale in vitro study focused on the effects of low level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system in order to test the hypothesis that modulated RF fields may act as a DNA damaging agent. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced different levels of DNA damage. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts from fetal lungs were exposed to mobile communication frequency radiation to investigate whether such exposure produced DNA strand breaks in cell culture. A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 2 and 24 h, while IMR-90 cells were exposed to both W-CDMA and CW radiations at a SAR of 80 mW/kg for the same time periods. Under the same RF field exposure conditions, no significant differences in the DNA strand breaks were observed between the test groups exposed to W-CDMA or CW radiation and the sham exposed negative controls, as evaluated immediately after the exposure periods by alkaline comet assays. Our results confirm that low level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.

  8. EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Characteristics of the evolution of a plasma formed by cw and pulse-periodic CO2 laser radiation in various gases (United States)

    Kanevskiĭ, M. F.; Stepanova, M. A.


    An investigation was made of the interaction between high-power cw and pulse-periodic CO2 laser radiation and a low-threshold optical breakdown plasma near a metal surface. Characteristics of the breakdown plasma were studied as a function of the experimental conditions. A qualitative analysis was made of the results using a simple one-dimensional model for laser combustion waves.

  9. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Spectroscopic investigation of thermodynamic parameters of a plasma plume formed by the action of cw CO2 laser radiation on a metal substrate (United States)

    Vasil'chenko, Zh V.; Azharonok, V. V.; Filatova, I. I.; Shimanovich, V. D.; Golubev, V. S.; Zabelin, A. M.


    Emission spectroscopy methods were used in an investigation of thermodynamic parameters of a surface plasma formed by the action of cw CO2 laser radiation of (2-5)×106 W cm-2 intensity on stainless steel in a protective He or Ar atmosphere. The spatiotemporal structure and pulsation characteristics of the plasma plume were used to determine the fields of the plasma electron density and temperature.

  10. Acute exposure to low-level CW and GSM-modulated 900 MHz radiofrequency does not affect Ba 2+ currents through voltage-gated calcium channels in rat cortical neurons. (United States)

    Platano, Daniela; Mesirca, Pietro; Paffi, Alessandra; Pellegrino, Monica; Liberti, Micaela; Apollonio, Francesca; Bersani, Ferdinando; Aicardi, Giorgio


    We have studied the non-thermal effects of radiofrequency (RF) electromagnetic fields (EMFs) on Ba(2+) currents (I Ba 2+) through voltage-gated calcium channels (VGCC), recorded in primary cultures of rat cortical neurons using the patch-clamp technique. To assess whether low-level acute RF field exposure could modify the amplitude and/or the voltage-dependence of I Ba 2+, Petri dishes containing cultured neurons were exposed for 1-3 periods of 90 s to 900 MHz RF-EMF continuous wave (CW) or amplitude-modulated according to global system mobile communication standard (GSM) during whole-cell recording. The specific absorption rates (SARs) were 2 W/kg for CW and 2 W/kg (time average value) for GSM-modulated signals, respectively. The results obtained indicate that single or multiple acute exposures to either CW or GSM-modulated 900 MHz RF-EMFs do not significantly alter the current amplitude or the current-voltage relationship of I Ba 2+, through VGCC. (c) 2007 Wiley-Liss, Inc.

  11. Rapid Sintering of Silica Xerogel Ceramic Derived from Sago Waste Ash Using Sub-millimeter Wave Heating with a 300 GHz CW Gyrotron (United States)

    Aripin, Haji; Mitsudo, Seitaro; Sudiana, I. Nyoman; Tani, Shinji; Sako, Katsuhide; Fujii, Yutaka; Saito, Teruo; Idehara, Toshitaka; Sabchevski, Sliven


    In this paper, we present and discuss experimental results from a microwave sintering of a silica-glass ceramic, produced from a silica xerogel extracted from a sago waste ash. As a radiation source for the microwave heating a sub-millimeter wave gyrotron (Gyrotron FU CW I) with an output frequency of 300 GHz has been used. The powders of silica xerogel have been dry pressed and then sintered at temperatures ranging from 300°C to 1500°C. The influence of the sintering temperature on the technological properties such as porosity and bulk density was studied in detail. Furthermore, X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy have been used in order to study the structure of the produced silica glass-ceramics. It has been found that the silica xerogel crystallizes at a temperature of 800°C, which is about 200°C lower than the one observed in the conventional process. The silica xerogel samples sintered by their irradiation with a sub-millimeter wave at 900°C for 18 minutes are fully crystallized into a silica glass-ceramic with a density of about 2.2 g/cm3 and cristobalite as a major crystalline phase. The results obtained in this study allow one to conclude that the microwave sintering with sub-millimeter waves is an appropriate technological process for production of silica glass-ceramics from a silica xerogel and is characterized with such advantages as shorter times of the thermal cycle, lower sintering temperatures and higher quality of the final product.

  12. HUNDSONAR (CW2015, ES60) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — HUDSONAR is a bioacoustic survey of the Hudson River Estuary being conducted aboard the Hudson River Sloop Clearwater by the Acoustic Laboratory for Ecology Studies...

  13. HUDSONAR (CW2013, EK60) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — HUDSONAR is a bioacoustic survey of the Hudson River Estuary being conducted aboard the Hudson River Sloop Clearwater by the Acoustic Laboratory for Ecology Studies...

  14. Wildevoelvlei/Noordhoek (CW28)

    CSIR Research Space (South Africa)

    Heinecken, TJE


    Full Text Available . Furthermore because of the inter-relationship between a high water table and the vleis and pans in the Noordehoek and Kommetjie basin, the two Wildevoelvlei cannot be considered in isolation from the other water bodies in the basin. Although, there does...

  15. HUDSONAR (CW2014, EK60) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — HUDSONAR is a bioacoustic survey of the Hudson River Estuary being conducted aboard the Hudson River Sloop Clearwater by the Acoustic Laboratory for Ecology Studies...

  16. The near infrared spectrum of ozone by CW-cavity ring down spectroscopy between 5850 and 7000 cm(-1): new observations and exhaustive review. (United States)

    Campargue, A; Barbe, A; De Backer-Barilly, M-R; Tyuterev, Vl G; Kassi, S


    Weak vibrational bands of (16)O(3) could be detected in the 5850-7030 cm(-1) spectral region by CW-cavity ring down spectroscopy using a set of fibered DFB diode lasers. As a result of the high sensitivity (noise equivalent absorption alpha(min) approximately 3 x 10(-10) cm(-1)), bands reaching a total of 16 upper vibrational states have been previously reported in selected spectral regions. In the present report, the analysis of the whole investigated region is completed by new recordings in three spectral regions which have allowed: (i) a refined analysis of the nu(1) + 3nu(2) + 3nu(3) band from new spectra in the 5850-5900 cm(-1) region; (ii) an important extension of the assignments of the 2nu(1)+5nu(3) and 4nu(1) + 2nu(2) + nu(3) bands in the 6500-6600 cm(-1) region, previously recorded by frequency modulation diode laser spectroscopy. The rovibrational assignments of the weak 4nu(1) + 2nu(2) + nu(3) band were fully confirmed by the new observation of the 4nu(1) + 2nu(2) + nu(3)- nu(2) hot band near 5866.9 cm(-1) reaching the same upper state; (iii) the observation and modelling of three A-type bands at 6895.51, 6981.87 and 6990.07 cm(-1) corresponding to the highest excited vibrational bands of ozone detected so far at high resolution. The upper vibrational states were assigned by comparison of their energy values with calculated values obtained from the ground state potential energy surface of (16)O(3). The vibrational mixing and consequently the ambiguities in the vibrational labelling are discussed. For each band or set of interacting bands, the spectroscopic parameters were determined from a fit of the corresponding line positions in the frame of the effective Hamiltonian (EH) model. A set of selected absolute line intensities was measured and used to derive the parameters of the effective transition moment operator. The exhaustive review of the previous observations gathered with the present results is presented and discussed. It leads to a total number

  17. Highly efficient 2  μm CW and Q-switched Tm3+:Lu2O3 ceramics lasers in-band pumped by a Raman-shifted erbium fiber laser at 1670  nm. (United States)

    Antipov, Oleg; Novikov, Anton; Larin, Sergey; Obronov, Ivan


    Highly efficient laser oscillations at 2 μm were investigated in Tm:Lu2O3 ceramics in-band pumped at 1670 nm by a Raman-shifted erbium fiber laser. Both 23 W CW and 15 W active Q-switched oscillations with 40 ns pulse duration and 15-30 kHz repetition rate were achieved in a high-quality beam. The evolution of two generated waves at 1966 and 2064 nm in dependence on pump power was studied.

  18. Molecular cloning of kman coding for mannanase from Klebsiella oxytoca KUB-CW2-3 and its hybrid mannanase characters. (United States)

    Pongsapipatana, Nawapan; Damrongteerapap, Piyanat; Chantorn, Sudathip; Sintuprapa, Wilawan; Keawsompong, Suttipun; Nitisinprasert, Sunee


    Gene encoding for β-mannanase (E.C from Klebsiella oxytoca KUB-CW2-3 was cloned and expressed by an E. coli system resulting in 400 times higher mannanase activities than the wild type. A 3314bp DNA fragment obtained revealed an open reading frame of 1164bp, namely kman-2, which encoded for 387 amino acids with an estimated molecular weight of 43.2kDa. It belonged to the glycosyl hydrolase family 26 (GH26) exhibited low similarity of 50-71% to β-mannanase produced by other microbial sources. Interestingly, the enzyme had a broad range of substrate specificity of homopolymer of ivory nut mannan (6%), carboxymethyl cellulose (30.6%) and avicel (5%), and heteropolymer of konjac glucomannan (100%), locust bean gum (92.6%) and copra meal (non-defatted 5.3% and defatted 7%) which would be necessary for in vivo feed digestion. The optimum temperature and pH were 30-50°C and 4-6, respectively. The enzyme was still highly active over a low temperature range of 10-40°C and over a wide pH range of 4-10. The hydrolysates of konjac glucomannan (H-KGM), locust bean gum (H-LBG) and defatted copra meal (H-DCM) composed of compounds which were different in their molecular weight range from mannobiose to mannohexaose and unknown oligosaccharides indicating the endo action of mannanase. Both H-DCM and H-LBG enhanced the growth of lactic acid bacteria and some pathogens except Escherichia coli E010 with a specific growth rate of 0.36-0.83h(-1). H-LBG was more specific to 3 species of Weissella confusa JCM 1093, Lactobacillus reuteri KUB-AC5, Lb salivarius KL-D4 and E. coli E010 while both H-KGM and H-DCM were to Lb. reuteri KUB-AC5 and Lb. johnsonii KUNN19-2. Based on the nucleotide sequence of kman-2 containing two open reading frames of 1 and 2at 5' end of the +1 and +43, respectively, removal of the first open reading frame provided the recombinant clone E. coli KMAN-3 resulting in the mature protein of mannanase composing of 345 amino acid residues confirmed by 3D

  19. EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Dynamics of a plasma formed by a surface optical-discharge in a metal vapour interacting with a cw CO2 laser beam (United States)

    Zaikin, A. E.; Levin, A. V.; Petrov, A. L.


    A surface optical-discharge plasma was formed in a metal vapour under normal conditions by steady-state irradiation with a cw CO2 laser delivering radiation of moderate (2-4.5 MW cm-2) intensity. This plasma strongly screened the irradiated surface. Under the selected experimental conditions the optical discharge was not a continuous (steady-state) process. The plasma cloud was displaced along the beam out of the waist to a region where the laser radiation intensity was almost an order of magnitude less than the threshold for excitation of the optical-discharge plasma in the vapour. A strong screening of the metal surface, which could even completely stop evaporation of the metal, was observed. Self-oscillations of the optical-discharge plasma were observed for the first time in a vapour interacting with cw CO2 radiation: this was attributed to screening of the target surface. Within one period of the self-oscillations there were additional hf plasma pulsations which led to stratification of the plasma cloud. The results obtained were interpreted.

  20. Phosphorylation and gene expression of p53 are not affected in human cells exposed to 2.1425 GHz band CW or W-CDMA modulated radiation allocated to mobile radio base stations. (United States)

    Hirose, H; Sakuma, N; Kaji, N; Suhara, T; Sekijima, M; Nojima, T; Miyakoshi, J


    A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields induce apoptosis or other cellular stress response that activate p53 or the p53-signaling pathway. First, we evaluated the response of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and wideband code division multiple access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced apoptosis or any signs of stress. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg, and CW radiation at 80 mW/kg for 24 or 48 h. Human IMR-90 fibroblasts from fetal lungs were exposed to both W-CDMA and CW radiation at a SAR of 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the percentage of apoptotic cells were observed between the test groups exposed to RF signals and the sham-exposed negative controls, as evaluated by the Annexin V affinity assay. No significant differences in expression levels of phosphorylated p53 at serine 15 or total p53 were observed between the test groups and the negative controls by the bead-based multiplex assay. Moreover, microarray hybridization and real-time RT-PCR analysis showed no noticeable differences in gene expression of the subsequent downstream targets of p53 signaling involved in apoptosis between the test groups and the negative controls. Our results confirm that exposure to low-level RF signals up to 800 mW/kg does not induce p53-dependent apoptosis, DNA damage, or other stress response in human

  1. Far-infrared cw difference-frequency generation using vertically integrated and planar low temperature grown GaAs photomixers: application to H2S rotational spectrum up to 3 THz (United States)

    Mouret, G.; Matton, S.; Bocquet, R.; Hindle, F.; Peytavit, E.; Lampin, J. F.; Lippens, D.


    The generation of continuous coherent THz radiation by mixing two cw Ti:Sa laser beams with a well-controlled frequency separation for a new scheme of vertically integrated low temperature grown GaAs (LTG-GaAs) spiral photomixer is reported. For this new photomixer device used in THz emission, the LTG-GaAs active layer is sandwiched between the two parallel metal plates of a high-speed photodetector loaded by a broadband spiral antenna. We have exploited the advantage of a higher delivered power in the low part of the spectrum (detector was used at the upper frequency. The performances of the spectroscopic setup in terms of spectral resolution (5 MHz), tunability and frequency capability are assessed by measurements of the pure rotational spectra of hydrogen sulfide (H2S) up to 3000 GHz.

  2. Side-pumped Nd:YVO{sub 4} cw laser with grazing-incidence small angle configuration; Laser de Nd:YVO{sub 4} bombeado transversalmente em configuracao com angulo rasante interno

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, Fabiola de Almeida


    Within the existing variety of laser cavity geometries and gain materials there is one combination that is particularly interesting because of its reduced complexity and high efficiency: the edge-pumped slab-laser using grazing-incidence geometry and a gain media with a very high pump absorption cross-section. In this work we studied a diode side-pumped Nd:YVO{sub 4} cw laser. We describe a single and a multiple bounce laser configurations. We demonstrate 22 W of multimode output power for 35 watts of pump power with a single pass through the gain media. A high optical-to-optical conversion efficiency of 63% and a slope efficiency of 74% with a very compact and simple Nd:YVO{sub 4} cavity that uses joint stability zones was achieved. The beam quality was M{sup 2} = 26 x 11 in the horizontal and vertical direction, respectively. With a double pass configuration we achieved 17 watts with a better beam quality of M{sup 2} = 3,4 x 3,7, in the horizontal and vertical direction, respectively. (author)

  3. CW Energy Recovery Operation of XFELs

    Energy Technology Data Exchange (ETDEWEB)

    Jacek Sekutowicz; S. Bogacz; Dave Douglas; Peter Kneisel; Gwyn P. Wiliams; Massimo Ferrario; Luca Serafini; Ilan Ben-Zvi; James Rose; Triveni Srinivasan-Rao; Patrick Colestock; Wolf-Dietrich Moeller; Bernd Petersen; Dieter Proch; S. Simrock; James B. Rosenzweig


    Commissioning of two large coherent light facilities at SLAC and DESY should begin in 2008 and in 2011 respectively. In this paper we look further into the future, hoping to answer, in a very preliminary way, two questions. First: What will the next generation of the XFEL facilities look like ? Believing that super-conducting technology offers several advantages over room-temperature technology, such as high quality beams with highly populated bunches and the possibility of energy recovery or higher overall efficiency, we focus this preliminary study on the superconducting option. From this belief the second question arises: ''What modifications in superconducting technology and in machine design are needed, as compared to the present DESY XFEL, and what kind of R&D program is required over the next few years to arrive at a technically feasible solution with even higher brilliance and increased overall conversion of AC power to photon beam power. In this paper we will very often refer to and profit from the DESY XFEL design, acknowledging its many technically innovative solutions.

  4. Design of multi-frequency CW radars

    CERN Document Server

    Jankiraman, Mohinder


    This book deals with the basic theory for design and analysis of Low Probability of Intercept (LPI) radar systems. The design of one such multi-frequency high resolution LPI radar, PANDORA, is covered.

  5. CW ESR studies on endohedral fullerenes (United States)

    Bartl, Anton; Dunsch, Lothar; Kirbach, Uwe


    Electron spin resonance (ESR) spectroscopy is used in this study in connection with the mass spectrometry one of the most promising method to characterize the state of endohedral fullerenes. The aim of this contribution is to study scandium, yttrium, lanthanum, cerium, praseodymium, samarium, europium, holmium, thulium and lutetium containing fullerenes in dependence on the production and handling conditions with respect to their electronic structure. For the most metallofullerenes both single filled and double filled fullerenes were measured. The mass spectrometric signals of single filled fullerenes are much larger than the signals of double and higher filled metallofullerenes. ESR spectroscopic properties were followed especially in solution of isolated metallofullerenes of high purity characterized by well resolved ESR spectra but also of the solid soot extract resulting in low resolved ESR spectra. In this way new information on the electronic states and the influence of oxygen on endohedral metallofullerene were obtained. The interaction of the lanthanofullerence with oxygen is studied in detail. Different stabilities in different solvents in the presence of oxygen were found for La at C82 molecules. For scandium, yttrium and lanthanum containing fullerenes ESR spectra with hyperfine structure splittings corresponding to the nuclear spin of the metal ion were found. Experiments with lanthanoides results in fullerenes, showing mass spectra with lines equivalent to the corresponding endohedral compounds with single and double filed cages, but no ESR spectra due to the interaction of an unpaired electron with the nuclear spin of the lanthanoide ion could be detected in the magnetic field range of 0 to 800 mT.

  6. Seventeenth "CW" Survey of Audiovisual Materials (United States)

    Seittelman, Elizabeth E.


    This survey is an annotated list of films, filmstrips, slides, transparencies, pictures and prints, posters and charts, maps, replicas and models, coloring books and puzzles, jewelry, recordings and catalogs dealing with classical history and languages. Addresses of producers and suppliers are included. (CK)

  7. On the possibility of developing quasi-CW high-power high-pressure laser on 4p–4s transition of ArI with electron beam—optical pumping: quenching of 4s (3P2) lower laser level (United States)

    Ionin, A. A.; Kholin, I. V.; L’dov, A. Yu; Seleznev, L. V.; Ustinovskii, N. N.; Zayarnyi, D. A.


    A new electron beam-optical procedure is proposed for quasi-cw pumping of high-pressure large-volume He–Ar laser on the 4p[1/2]1–4s[3/2]20 argon atom transition at the wavelength of 912.5 nm. It consists of creation and maintenance of a necessary density of the 4s[3/2]20 metastable state in the gain medium by a fast electron beam and subsequent optical pumping of the upper laser level via the classical three-level scheme using a laser diode. Absorption probing is used to study collisional quenching of Ar* metastable in electron-beam-excited high-pressure He–Ar mixtures with a low content of argon. The rate constants for plasma-chemical reactions Ar*  +  He  +  Ar  >  Ar2*   +  He (3.6  ±  0.4)  ×  10‑33 cm6 s‑1, Ar*  +  2He  >  HeAr*  +  He (4.4  ±  0.9)  ×  10‑36 cm6 s‑1 and Ar*  +  He  >  Products  +  He (2.4  ±  0.3)  ×  10‑15 cm3 s‑1 were for the first time measured.

  8. Production of CW and mode-locked atom lasers (United States)

    Bouyer, P.; Rangwala, S. A.; Thywissen, J. H.; Le Coq, Y.; Gerbier, F.; Richard, S.; Delannoy, G.; Aspect, A.


    Nous étudions les propriétés des faisceaux cohérents atomique à partir d'un condensat de Bose Einstein. Grâce à un contrôle précis du coupleur de sortie, il est possible, comme en optique, de produire des faisceaux laser monomodes, multiples ou mode-lockés. De plus, on peut montrer que la propagation du faisceau peut être décrite par des matrices ABCD similaires à celles qui sont utilisées en optique. Néanmoins, les interactions entre atomes, qui sont inexistantes entre les photons, conduisent quelques différences entre les propriétés de collimation des lasers atomes et photoniques.

  9. High Power CW Superconducting Linacs for EURISOL and XADS

    CERN Document Server

    Biarrotte, J L


    A multi-MW superconducting proton linac is proposed as the baseline solution for the EURISOL and the XADS driver accelerators. In the EURISOL project, which studies the design of the next-generation European ISOL facility, it is used to produce both neutron-deficient and neutron-rich exotic nuclei far from the valley of stability. In the PDS-XADS project, which aims to the demonstration of the feasibility of an ADS system for nuclear waste transmutation, it is used to produce the neutron flux required by the associated sub-critical reactor. In this paper, we report the main results and conclusions reached within these preliminary design studies. A special emphasis is given on the on-going and future R&D to be done to accomplish the demonstration of the full technology.

  10. [CW bio-radar vital sign detector and experiment study]. (United States)

    Hu, Wei; Wang, Yunfeng; Zhao, Zhangyan; Zhang, Haiying


    Non-contact vital sign detection technique provides an effective usage in health monitoring applications. A vital sign detector was designed based on microwave bio-radar technique. Using Doppler principle, continuous wave bioradar was designed for tiny body movement detection, short-time Fourier transform and interpolation algorithm were adopted for heart and respiration rate extraction, embedded system was used for system integration, real-time signal processing software was designed on it. Experiments were done by using simulation device and human body for research and performance evaluation. The result shows that the proposed prototype can be used for single target vital signs detection at the distance of 90 cm, and the heart rate result shows a 96% recognition rate.

  11. Processing of dual-orthogonal cw polarimetric radar signals

    NARCIS (Netherlands)

    Babur, G.


    The thesis consists of two parts. The first part is devoted to the theory of dual-orthogonal polarimetric radar signals with continuous waveforms. The thesis presents a comparison of the signal compression techniques, namely correlation and de-ramping methods, for the dual-orthogonal sophisticated

  12. Decontamination of Casualties from Battlefield Under CW and BW Attack (United States)


    dichromate, peroxyacid , and hypochlorite did not react with EEMPT and reacted with DECP only if the film was moist. The colored films from permanganate... peroxyacid films were wetted and then treated with CEES (Tables XX, XXI and XXII). 3. Detector Films Several of the films were colorless because of the

  13. CW 100MW microwave power transfer in space

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, K. (Houston Univ., TX (United States). Inst. for Beam Particle Dynamics National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan) Texas Accelerator Center, The Woodlands, TX (United States)); Hiramatsu, S. (National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)); Shiho, M. (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan))


    A proposal is made for high-power microwave transfer in space. The concept consists in a microwave power station integrating a multistage microwave free-electron laser and asymmetric dual-reflector system. Its use in space is discussed. 9 refs., 2 figs., 1 tab.

  14. FM-CW Based Miniature SAR System for Small UAVs

    NARCIS (Netherlands)

    Hoogeboom, P.; Wit, J.J.M. de; Meta, A.; Figueras, J.


    In some earth observation applications there is a requirement for low cost, high performance imaging radar systems small enough to be operated from small, even unmanned, aircraft. The existing pulse radars are non-cost effective complex systems. Therefore they are not suited for these applications.

  15. Parametric Four-Wave Mixing Using a Single cw Laser (United States)

    Brekke, Erik; Herman, Emily; Alderson, Laura


    We present progress in using parametric four-wave mixing in a rubidium cell for the generation of coherent emission at 420 nm and 5.4 μm. A simple system using a single external cavity diode laser at 778 nm and a tapered amplifier supplies the needed optical beams. The efficiency is limited by absorption of the 420 nm beam, with single pass outputs of 40 μW. Optical pumping presents a possibility for increased output powers, but radiation trapping must be overcome at high densities. Several methods for increasing the effectiveness of the process are currently underway. The resulting beam at 420 nm presents an intriguing alternative method of exciting Rydberg states in Rubidium atoms.

  16. AM-CW Integrated Path Differential Absorption Lidar Project (United States)

    National Aeronautics and Space Administration — This proposal addresses NASA's science objectives with innovative lidar architecture for atmospheric CO2 measurements. Specifically, the proposed work can support...

  17. Generation conditions of CW Diode Laser Sustained Plasma (United States)

    Nishimoto, Koji; Matsui, Makoto; Ono, Takahiro


    Laser sustained plasma was generated using 1 kW class continuous wave diode laser. The laser beam was focused on the seed plasma generated by arc discharge in 1 MPa xenon lamp. The diode laser has advantages of high energy conversion efficiency of 80%, ease of maintenance, compact size and availability of conventional quartz based optics. Therefore, it has a prospect of further development compared with conventional CO2 laser. In this study, variation of the plasma shape caused by laser power is observed and also temperature distribution in the direction of plasma radius is measured by optical emission spectroscopy.

  18. Nonlinear optical studies of curcumin metal derivatives with cw laser

    Energy Technology Data Exchange (ETDEWEB)

    Henari, F. Z., E-mail:; Cassidy, S. [Department of Basic Medical Sciences, Royal College of Surgeons in Ireland, Medical University of Bahrain (Bahrain)


    We report on measurements of the nonlinear refractive index and nonlinear absorption coefficients for curcumin and curcumin metal complexes of boron, copper, and iron at different wavelengths using the Z-scan technique. These materials are found to be novel nonlinear media. It was found that the addition of metals slightly influences its nonlinearity. These materials show a large negative nonlinear refractive index of the order of 10{sup −7} cm{sup 2}/W and negative nonlinear absorption of the order of 10{sup −6} cm/W. The origin of the nonlinearity was investigated by comparison of the formalism that is known as the Gaussian decomposition model with the thermal lens model. The optical limiting behavior based on the nonlinear refractive index was also investigated.

  19. Tunable cw UV laser with spectroscopy of Sr Rydberg states. (United States)

    Bridge, Elizabeth M; Keegan, Niamh C; Bounds, Alistair D; Boddy, Danielle; Sadler, Daniel P; Jones, Matthew P A


    We present a solid-state laser system that generates over 200 mW of continuous-wave, narrowband light, tunable from 316.3 nm - 317.7 nm and 318.0 nm - 319.3 nm. The laser is based on commercially available fiber amplifiers and optical frequency doubling technology, along with sum frequency generation in a periodically poled stoichiometric lithium tantalate crystal. The laser frequency is stabilized to an atomic-referenced high finesse optical transfer cavity. Using a GPS-referenced optical frequency comb we measure a long term frequency instability of spectroscopy of Sr Rydberg states from n = 37 - 81, demonstrating mode-hop-free scans of 24 GHz. In a cold atomic sample we measure Doppler-limited linewidths of 350 kHz.

  20. A Passive Multistatic CW Radar System using Geostationary Illuminators


    Thölert, Steffen; Hounam, David


    In this paper a new passive radar system using a geostationary TV satellite as an illuminator and ground-based receivers is presented. The system can be operated as a monostatic or multistatic radar and can be used for target detection or reflectivity measurements. Full polarimetric operation is possible. The measurement technique and the system hardware of an experimental system are described, particular attention being paid to the methods of signal synchronization. The results of experiment...

  1. CW STED nanoscopy with a Ti:Sapphire oscillator (United States)

    Liu, Yujia; Xie, Hao; Alonas, Eric; Santangelo, Philip J.; Jin, Dayong; Xi, Peng


    Fluorescence microscopy has become an essential tool to study biological molecules, pathways and events in living cells, tissues and animals. Meanwhile, the conventional optical microscopy is limited by the wavelength of the light. Even the most advanced confocal microscopy or multiphoton microscopy can only yield optical resolution approaching the diffraction limit of ~200 nm. This is still larger than many subcellular structures, which are too small to be resolved in detail. These limitations have driven the development of super-resolution optical imaging methodologies over the past decade. The stimulated emission depletion (STED) microscopy was the first and most direct approach to overcoming the diffraction limit for far-field nanoscopy. Typically, the excitation focus is overlapped by an intense doughnut-shaped spot to instantly de-excite markers from their fluorescent state to the ground state by stimulated emission. This effectively eliminates the periphery of the Point Spread Function (PSF), resulting in a narrower focal region, or super-resolution. Scanning a sharpened spot through the specimen renders images with sub-diffraction resolution. Multi-color STED imaging can present important structural and functional information for protein-protein interaction. In this work, we presented a dual color, synchronization-free STED stimulated emission depletion (STED) microscopy with a Ti:Sapphire oscillator. The excitation wavelengths were 532nm and 635nm, respectively. With pump power of 4.6 W and sample irradiance of 310 mW, we achieved super-resolution as high as 71 nm. We also imaged 200 nm nanospheres as well as all three cytoskeletal elements (microtubules, intermediate filaments, and actin filaments), clearly demonstrating the super-resolution resolving power over conventional diffraction limited imaging. It also allowed us to discover that, Dylight 650, exhibits improved performance over ATTO647N, a fluorophore frequently used in STED. Furthermore, we applied synchronization-free STED to image fluorescently-labeled intracellular viral RNA granules, which otherwise cannot be differentiated by confocal microscopy. Thanks to the widely available Ti:Sapphire oscillators in multiphoton imaging system, this work suggests easier access to setup super-resolution microscope via the synchronization-free STED A series of biological specimens were imaged with our dual-color STED.


    The preparation of Adams’ most active tetrehydrocannabinol analog (Formula I, R=1,2-dimethylheptyl), and of synthetic tetrahydrocannabinol (I, R=n...beta-(3,5-dimethoxyphenyl) ethylanine. The pyrons related to tetrahydrocannabinol (II, R=n-amyl) has been reaction with aqueous ammonia to produce a high...amylphenol. An attempt will be made to condense this aminophenol with pulegone to give a nitrogen analog of tetrahydrocannabinol . The synthesis of pulegone from isopulegol has been accomplished.

  3. ARRA NEPA Quarterly Report- First Report: USACE-CW (United States)

    Council on Environmental Quality, Executive Office of the President — Reports prepared by the Departments and Agencies on status of NEPA progress for activities and projects funded under Division A of the American Recovery and...

  4. Selective control of HOD photodissociation using CW lasers

    Indian Academy of Sciences (India)


    noted by reaction coordinate ri, with H + O–D chan- nel labelled as 1 and H–O + D channel as 2. The expressions for the total flux J in the H + O–D and. H–O + D channels are given by,. 2. 2. 1. 2. 1. 2. 0 0 cos. ˆ. ˆ. *( , , ) d r T. H O D o. J. r r t j j m μ θ. + −. ⎛. ⎞. = Ψ. +. ⎜. ⎟. ⎝. ⎠. ∫ ∫. 1. 2. 2. ( , , ). ,. r r t drdt. Ψ. (5). 1. 1. H O+D.

  5. Adaptación de la metodología de procesos ITIL V2 de una empresa a ITIL V3


    González Ortiz, Andrés Francisco


    The main objective of this project is to adapt and improve Eurotrans process methodology from ITIL V2 to ITIL V3. For this I have used previous knowledge of the company Eurotrans and have worked based on the processes implemented in previous project. Some shortcomings present in ITIL V2 have been identified and have been corrected with the ITIL V3 implementation. For this purpose, all ITIL V2 processes implanted in Eurotrans has been analized and some improvements has been proposed following ...

  6. Comparison of the influence of acoustically enhanced pulsating water jet on selected surface integrity characteristics of CW004A copper and CW614N brass

    Czech Academy of Sciences Publication Activity Database

    Lehocká, D.; Klichová, Dagmar; Foldyna, Josef; Hloch, Sergej; Hvizdoš, P.; Fides, M.; Botko, F.


    Roč. 110, November 2017 (2017), s. 230-238 ISSN 0263-2241 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : pulsating water jet * surface integrity * mass material removal * copper * nanoindentation Subject RIV: JQ - Machines ; Tools Impact factor: 2.359, year: 2016

  7. Keyhole depth instability in case of CW CO2 laser beam welding of ...

    Indian Academy of Sciences (India)

    MS received 5 August 2009; revised 27 November 2009; accepted 30 November. 2009. Abstract. The study of keyhole (KH) instability in deep penetration laser beam welding (LBW) is essential to understand welding process and appearance of weld seam defects. The main cause of keyhole collapse is the instability in KH.

  8. High CW power, phase and amplitude modulatorrealized with fast ferrite phase-shifters

    CERN Document Server

    Valuch, D


    Superconducting cavity resonators are suffering from detuning effects caused by high internal electromagnetic fields (Lorentz force detuning). For classical resonators working with continuous wave signals, this detuning is static and compensated by the slow mechanical tuning system. However, pulsing of superconducting cavities, an operational mode only recently considered, results in dynamic detuning effects. New ways to handle this effect have to be found and worked out. A way to supply several superconducting cavities in the particle accelerator by one large transmitter while keeping the possibility of controlling the field in each individual cavity is shown. By introducing a fast phase and amplitude modulator into each cavity feeder line, the individual deviations of each cavity with respect to the average can be compensated in order to equalize their behaviour for the main control loop, which will compensate the global detuning of all cavities. Several types of phase and amplitude modulators suitable for ...

  9. A CW normal-conductive RF gun for free electron laser and energy recovery linac applications

    Energy Technology Data Exchange (ETDEWEB)

    Baptiste, Kenneth; Corlett, John; Kwiatkowski, Slawomir; Lidia, Steven; Qiang, Ji; Sannibale, Fernando; Sonnad, Kiran; Staples, John; Virostek, Steven; Wells, Russell


    Currently proposed energy recovery linac and high average power free electron laser projects require electron beam sources that can generate up to {approx} 1 nC bunch charges with less than 1 mmmrad normalized emittance at high repetition rates (greater than {approx} 1 MHz). Proposed sources are based around either high voltage DC or microwave RF guns, each with its particular set of technological limits and system complications. We propose an approach for a gun fully based on mature RF and mechanical technology that greatly diminishes many of such complications. The concepts for such a source as well as the present RF and mechanical design are described. Simulations that demonstrate the beam quality preservation and transport capability of an injector scheme based on such a gun are also presented.

  10. CW-EPR study of 2,2,4,4-tetramethyl-3-pentanone oxime single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sayin, Ulku; Yuksel, Huseyin; Ozmen, Ayhan [Physics Department, Selcuk University, Konya (Turkey); Birey, Mehmet, E-mail: [Physics Department, Ankara University, Ankara (Turkey)


    The electron paramagnetic resonance (EPR) spectra of gamma irradiated single crystals of 2,2,4,4-tetramethyl-3-pentanone oxime (TPO) have been examined between temperatures of 125 and 450 K. The spectra were found to be both dependent on temperature and orientation of single crystals with magnetic field. We attributed radiation damage centers to iminoxy radicals (RC=N{sup {center_dot}}O). There are two similar group of splitting in the spectra because of conformational isomers (R1, R2) of iminoxy radicals produced by gamma irradiation of TPO. Determined g-factor and hyperfine coupling constants for R1 and R2 conformers were found anisotropic with the average values (g{sub iso}){sub R1}=2.01057, (g{sub iso}){sub R2}=2.009337, [(a{sub N}){sub iso}]{sub R1}=28.09 G, [(a{sub N}){sub iso}]{sub R2}=36.34 G, [(a{sub H}){sub iso}]{sub R2}=9.15 G, respectively.

  11. Applications of cw quantum cascade laser near 8 μm in gas sensing research

    KAUST Repository

    Sajid, Muhammad Bilal


    Quantum cascade laser based sensors operating near 8 μm to detect H2O2, C2H2, CH4, N2O and H2O are discussed and demonstrated for applications in chemical kinetics, combustion and spectroscopic measurements.

  12. Permeation Studies of CW Agents with Fabric Treated with 8-Hydroxyquinoline (United States)


    4 Fabrics that were tested in this series are given in Table 6, with the additional sample of Sigmaversatech ( SVT ) fabric, a sample that was... SVT fabrics were not significantly different from the untreated fabrics. However, the SVT fabrics were heated to apply the omniphobic coating, and the...5 30 ug GD 1191 474 untr #1 594 272 291 346 285 untr #2 660 377 374 388 289 untr #3 632 372 327 291 182 SVT #1 339 317 343 373 318 SVT #2 277

  13. CW-pumped telecom band polarization entangled photon pair generation in a Sagnac interferometer. (United States)

    Li, Yan; Zhou, Zhi-Yuan; Ding, Dong-Sheng; Shi, Bao-Sen


    Polarization entangled photon pair source is widely used in many quantum information processing applications such as teleportation, quantum communications, quantum computation and high precision quantum metrology. We report on the generation of a continuous-wave pumped 1550 nm polarization entangled photon pair source at telecom wavelength using a type-II periodically poled KTiOPO(4) (PPKTP) crystal in a Sagnac interferometer. Hong-Ou-Mandel (HOM) interference measurement yields signal and idler photon bandwidth of 2.4 nm. High quality of entanglement is verified by various kinds of measurements, for example two-photon interference fringes, Bell inequality and quantum states tomography. The source can be tuned over a broad range against temperature or pump power without loss of visibilities. This source will be used in our future experiments such as generation of orbital angular momentum entangled source at telecom wavelength for quantum frequency up-conversion, entanglement based quantum key distributions and many other quantum optics experiments at telecom wavelengths.

  14. CW-pumped telecom band polarization entangled photon pair generation in a Sagnac interferometer


    Li, Yan; Zhou, Zhi-Yuan; Ding, Dong-Sheng; Shi, Bao-Sen


    A polarization entangled photon pair source is widely used in many quantum information processing applications such as teleportation, quantum swapping, quantum computation and high precision quantum metrology. Here, we report on the generation of a continuous-wave pumped degenerated 1550 nm polarization entangled photon pair source at telecom wavelength using a type-II phase-matched periodically poled KTiOPO4 crystal in a Sagnac interferometer. Hong-Ou-Mandel-type interference measurement sho...

  15. Laser sources for polarized electron beams in cw and pulsed accelerators

    CERN Document Server

    Hatziefremidis, A; Fraser, D; Avramopoulos, H


    We report the characterization of a high power, high repetition rate, mode-locked laser system to be used in continuous wave and pulsed electron accelerators for the generation of polarized electron beams. The system comprises of an external cavity diode laser and a harmonically mode-locked Ti:Sapphire oscillator and it can provide up to 3.4 W average power, with a corresponding pulse energy exceeding 1 nJ at 2856 MHz repetition rate. The system is tunable between 770-785 and 815-835 nm with two sets of diodes for the external cavity diode laser. (author)

  16. Photo-generated metamaterials induce modulation of CW terahertz quantum cascade lasers (United States)

    Mezzapesa, Francesco P.; Columbo, Lorenzo L.; Rizza, Carlo; Brambilla, Massimo; Ciattoni, Alessardro; Dabbicco, Maurizio; Vitiello, Miriam S.; Scamarcio, Gaetano


    Periodic patterns of photo-excited carriers on a semiconductor surface profoundly modifies its effective permittivity, creating a stationary all-optical quasi-metallic metamaterial. Intriguingly, one can tailor its artificial birefringence to modulate with unprecedented degrees of freedom both the amplitude and phase of a quantum cascade laser (QCL) subject to optical feedback from such an anisotropic reflector. Here, we conceive and devise a reconfigurable photo-designed Terahertz (THz) modulator and exploit it in a proof-of-concept experiment to control the emission properties of THz QCLs. Photo-exciting sub-wavelength metastructures on silicon, we induce polarization-dependent changes in the intra-cavity THz field, that can be probed by monitoring the voltage across the QCL terminals. This inherently flexible approach promises groundbreaking impact on THz photonics applications, including THz phase modulators, fast switches, and active hyperbolic media.

  17. Physics design of a CW high-power proton Linac for accelerator ...

    Indian Academy of Sciences (India)

    The accelerator for ADS should have high efficiency and reliability and very low beam losses to allow hands-on maintenance. With these criteria, the beam dynamics simulations for a 1 GeV, 30 mA proton Linac has been done. The Linac consists of normal-conducting radio-frequency quadrupole (RFQ), drift tube linac (DTL) ...

  18. Green bright squeezed light from a cw periodically poled KTP second harmonic generator

    DEFF Research Database (Denmark)

    Andersen, Ulrik Lund; Buchhave, Preben


    We present the experimental observation of bright amplitude squeezed light from a singly resonant second harmonic generator (SHG) based on a periodically poled potassium titanyl phosphate (KTP) crystal. Contrary to conventional SHG, the interacting waves in this device couple efficiently using...... quasi phase matching (QPM) and more importantly QPM allows access to higher valued elements of the nonlinear tensor than is possible under the constraint of birefringence phase matching. We observe a noise reduction of 13% below the shot noise limit in the generated second harmonic field. This noise...

  19. Keyhole depth instability in case of CW CO2 laser beam welding of ...

    Indian Academy of Sciences (India)

    LBW) is essential to understand welding process and appearance of weld seam defects. The main cause of keyhole collapse is the instability in KH dynamics during the LBW process. This is mainly due to the surface tension forces associated with ...

  20. Real time diagnostic for operation at a CW low voltage FEL

    Energy Technology Data Exchange (ETDEWEB)

    Balfour, C.; Shaw, A.; Mayhew, S.E. [and others


    At Liverpool University, a system for single user control of an FEL has been designed to satisfy the low voltage FEL (ie 200kV) operational requirements. This system incorporates many aspects of computer automation for beam diagnostics, radiation detection and vacuum system management. In this paper the results of the development of safety critical control systems critical control systems are reported.

  1. Functional imaging of muscle oxygenation using a 200-channel cw NIRS system (United States)

    Yamamoto, Katsuyuki; Niwayama, Masatsugu; Kohata, Daisuke; Kudo, Nobuki; Hamaoka, Takatumi; Kime, Ryotaro; Katsumura, Toshihito


    Functional imaging of muscle oxygenation using NIRS is a promising technique for evaluation of the heterogeneity of muscle function and diagnosis of peripheral vascular disease or muscle injury. We have developed a 200-channel imaging system that can measure the changes in oxygenation and blood volume of muscles and that covers wider area than previously reported systems. Our system consisted of 40 probes, a multiplexer for switching signals to and from the probes, and a personal computer for obtaining images. In each probe, one two-wavelength LED (770 and 830 nm) and five photodiodes were mounted on a flexible substrate. In order to eliminate the influence of a subcutaneous fat layer, a correction method, which we previously developed, was also used in imaging. Thus, quantitative changes in concentrations of oxy- and deoxy-hemoglobin were obtained. Temporal resolution was 1.5 s and spatial resolution was about 20 mm, depending on probe separations. Exercise tests (isometric contraction of 50% MVC) on the thigh with and without arterial occlusion were conducted, and changes in muscle oxygenation were imaged using the developed system. Results showed that the heterogeneity of deoxygenation and reoxygenation during exercise and recovery periods, respectively, were clearly observed. These results suggest that optical imaging of dynamic change in muscle oxygenation using NIRS would be useful not only for basic physiological studies but also for clinical applications with respect to muscle functions.

  2. Food foraging of honey bees in a microwave field (2. 45 GHz CW)

    Energy Technology Data Exchange (ETDEWEB)

    Gary, N.E.; Westerdahl, B.B.


    Honey bees were trained to fly 400 m from their colony to an indoor laboratory foraging arena exposed to 2.45 GHz continuous wave microwaves at 5 power densities (0, 5, 10, 20, and 40 mW/cm/sup 2/). Foraging behavior did not differ from controls foraging within an unexposed sham arena in (1) number of round trips completed during a 3-h exposure session, (2) round trip time between the colony and the foraging arena, and (3) the length of time required to navigate the illuminated foraging arena. This study indicates that honey bees would not be adversely affected by foraging within a similar microwave field that would exist in future receiving antennae for the proposed solar power satellite energy transmission system in which power levels are expected to range from 23 mW/cm/sup 2/ at the antenna center to 1 mW/cm/sup 2/ at the edge.

  3. Estimation of physiological sub-millimeter displacement with CW Doppler radar. (United States)

    Jia Xu; Xiaomeng Gao; Padasdao, Bryson E; Boric-Lubecke, Olga


    Doppler radar physiological sensing has been studied for non-contact detection of vital signs including respiratory and heartbeat rates. This paper presents the first micrometer resolution Wi-Fi band Doppler radar for sub-millimeter physiological displacement measurement. A continuous-wave Doppler radar working at 2.4GHz is used for the measurement. It is intended for estimating small displacements on the body surface resulting from physiological activity. A mechanical mover was used as target, and programmed to conduct sinusoidal motions to simulate pulse motions. Measured displacements were compared with a reference system, which indicates a superior performance in accuracy for having absolute errors less than 10μm, and relative errors below 4%. It indicates the feasibility of highly accurate non-contact monitoring of physiological movements using Doppler radar.

  4. Development of a CW Superconducting RF Booster Cryomodule for Future Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, Terry L; Bogle, Andrew; Deimling, Brian; Hollister, Jerry; II, Randall Jecks; Kolka, Ahren; Romel, Chandra


    Future light sources based on seeded free electron lasers (FEL) have the potential to increase the soft xray flux by several orders of magnitude with short bunch lengths to probe electron structure and dynamics. A low emittance, high rep-rate radio frequency (RF) photocathode electron gun will generate the electron beam that will require very stringent beam control and manipulation through the superconducting linear accelerator to maintain the high brightness required for an x-ray FEL. The initial or booster cavities of the superconducting radio frequency (SRF) linear accelerator will require stringent control of transverse kicks and higher order modes (HOM) during the beam manipulation and conditioning that is needed for emittance exchange and bunch compression. This SBIR proposal will develop, fabricate and test a continuous-wave SRF booster cryomodule specifically for this application. Phase I demonstrated the technical feasibility of the project by completing the preliminary SRF cavity and cryomodule design and its integration into an R&D test stand for beam studies at Lawrence Berkeley National Laboratory (LBNL). The five-cell bulk niobium cavities operate at 750 MHz, and generate 10 MV each with strong HOM damping and special care to eliminate transverse kicks due to couplers. Due to continuous-wave operation at fairly modest beam currents and accelerating gradients the complexity of the two cavity cryomodule is greatly reduced compared to an ILC type system. Phase II will finalize the design, and fabricate and test the booster cryomodule. The cryomodule consists of two five-cell cavities that will accelerate megahertz bunch trains with nano-coulomb charge. The accelerating gradient is a very modest 10 MV/m with peak surface fields of 20 MV/m and 42.6 mT. The cryogenic system operates at 2 K with a design dynamic load of 20 W and total required cryogenic capacity of 45 W. The average beam current of up to 1 mA corresponds to a beam power of 10 kW per 5- cell cavity and will require 20 kW of RF power for transmission, control and regulation. The RF power will be supplied by a commercial tetrode. Cryogenic tests will be carried out at LBNL to make use of their test facilities, cryogenics and laser systems, and for future use with beam. Demonstration of this new type of booster cryomodule will open many new applications of SRF linear accelerators.

  5. Improving the resolution of a stepped frequency cw ground-penetrating radar (United States)

    Langman, Alan; Inggs, Michael R.; Flores, Benjamin C.


    One of the major problems in sub-surface radar is the compromise between resolution and penetration depth. Stepped frequency continuous wave radars (SFCW) have improved the penetration depth of sub-surface radars by achieving greater sensitivity, instantaneous dynamic range, and better spectral control than conventional pulsed systems. However, the resolution in SFCW radar systems is limited by the fast Fourier transform (FFT) processing required to extract depth (i.e., range) information from the vector frequency data. This paper investigates the potential use of the extended prony method for range extraction in a SFCW ground penetrating radar (GPR). This method fits data to a complex exponential model, without placing the restriction on the data that the targets are constrained to definite range bins. This allows for the resolution of the system to go beyond the limitations set by the bandwidth of the waveform. Simulations are presented to examine the effects of the signal-to-noise ratio (SNR) on performance, when applying the extended prony method to a simple GPR model. At all times the results are compared with the standard FFT processing. A prototype radar system has been constructed at the University of Cape Town using standard laboratory equipment, a computer and additional digital and rf circuitry. The antennas used are two ridged wideband horns. Targets were buried in a sandpit and measurements were taken over a 2 GHz bandwidth with a center frequency of 3 GHz. Comparisons ware made between the FFT and the extended prony method for different portions of the system bandwidth, showing the extended prony method can achieve high resolution using a reduced bandwidth.

  6. Natural Hypolignification Is Associated with Extensive Oligolignol Accumulation in Flax Stems1[C][W (United States)

    Huis, Rudy; Morreel, Kris; Fliniaux, Ophélie; Lucau-Danila, Anca; Fénart, Stéphane; Grec, Sébastien; Neutelings, Godfrey; Chabbert, Brigitte; Mesnard, François; Boerjan, Wout; Hawkins, Simon


    Flax (Linum usitatissimum) stems contain cells showing contrasting cell wall structure: lignified in inner stem xylem tissue and hypolignified in outer stem bast fibers. We hypothesized that stem hypolignification should be associated with extensive phenolic accumulation and used metabolomics and transcriptomics to characterize these two tissues. 1H nuclear magnetic resonance clearly distinguished inner and outer stem tissues and identified different primary and secondary metabolites, including coniferin and p-coumaryl alcohol glucoside. Ultrahigh-performance liquid chromatography-Fourier transform ion cyclotron resonance-mass spectrometry aromatic profiling (lignomics) identified 81 phenolic compounds, of which 65 were identified, to our knowledge, for the first time in flax and 11 for the first time in higher plants. Both aglycone forms and glycosides of monolignols, lignin oligomers, and (neo)lignans were identified in both inner and outer stem tissues, with a preponderance of glycosides in the hypolignified outer stem, indicating the existence of a complex monolignol metabolism. The presence of coniferin-containing secondary metabolites suggested that coniferyl alcohol, in addition to being used in lignin and (neo)lignan formation, was also utilized in a third, partially uncharacterized metabolic pathway. Hypolignification of bast fibers in outer stem tissues was correlated with the low transcript abundance of monolignol biosynthetic genes, laccase genes, and certain peroxidase genes, suggesting that flax hypolignification is transcriptionally regulated. Transcripts of the key lignan genes Pinoresinol-Lariciresinol Reductase and Phenylcoumaran Benzylic Ether Reductase were also highly abundant in flax inner stem tissues. Expression profiling allowed the identification of NAC (NAM, ATAF1/2, CUC2) and MYB transcription factors that are likely involved in regulating both monolignol production and polymerization as well as (neo)lignan production. PMID:22331411

  7. Isotopically selective RIMS of rare radionuclides by double-resonance excitation with cw lasers

    Energy Technology Data Exchange (ETDEWEB)

    Bushaw, B.A.; Munley, J.T.


    Double-resonance, Resonance Ionization Mass Spectroscopy (RIMS) using two single-frequency dye lasers and a CO{sub 2} laser for photoionization has been shown to be both extremely sensitive and highly selective. Measurements on the radioisotope {sup 210}Pb have demonstrated optical selectivity in excess of 10{sup 9} and detection limits of less than 1 femtogram.

  8. The Effects of CW (Chemical Warfare)-Related Chemicals on Social Behavior and Performance (United States)


    is the hierarchy of matriarchies , such that each female and her daughters are a social unit and each such unit has a social rank within the troop. The...females and the members of their matriarchies show the highest frequncies of these behaviors. Agonistic behavior within matriarchies and between lower...ranking matriarchies is less frequent. Subadult and the older juvenile males tend to interact largely with each other and with young juveniles rather

  9. The Effects of CW-Related Chemicals on Social Behavior and Performance (United States)


    while the second consists of a social hierarchy of the matriarchies present in the group. In a matriarchy , an old female, her daughters, her daughters...accompanied by a corresponding change in the status of the members of her matriarchy (Angst, 1975). The two kinds of hierarchies function to promote cohesion... matriarchies seem to function more or less independently within the group. Males tend to interact with other adult males in the hierarchy and with 19

  10. Crystalline magnetic carbon nanoparticle assisted photothermal delivery into cells using CW near-infrared laser beam. (United States)

    Gu, Ling; Koymen, Ali R; Mohanty, Samarendra K


    Efficient and targeted delivery of impermeable exogenous material such as small molecules, proteins, and plasmids into cells in culture as well as in vivo is of great importance for drug, vaccine and gene delivery for different therapeutic strategies. Though advent of optoporation by ultrafast laser microbeam has allowed spatial targeting in cells, the requirement of high peak power to create holes on the cell membrane is not practical and also challenging in vivo. Here, we report development and use of uniquely non-reactive crystalline magnetic carbon nanoparticles (CMCNPs) for photothermal delivery (PTD) of impermeable dyes and plasmids encoding light-sensitive proteins into cells using low power continuous wave near-infrared (NIR) laser beam. Further, we utilized the magnetic nature of these CMCNPs to localize them in desired region by external magnetic field, thus minimizing the required number of nanoparticles. We discovered that irradiation of the CMCNPs near the desired cell(s) with NIR laser beam leads to temperature rise that not only stretch the cell-membrane to ease delivery, it also creates fluid flow to allow mobilization of exogenous substances to the delivery. Due to significant absorption properties of the CMCNPs in the NIR therapeutic window, PTD under in vivo condition is highly possible.

  11. Effect of Nd 3+concentration on CW and pulsed performance of fiber ...

    Indian Academy of Sciences (India)

    pump radiation absorption inside the crystal. It must be kept in mind that in OEM pack- aged laser diodes there is some thermal resistance between .... refractive index profile results in a variation of the phase front. The phase profile induced by the pumping beam creates a positive lensing effect due to the positive thermal- ...

  12. The Effects of CW (Chemical Warfare)-Related Chemicals on Social Behavior and Performance (United States)


    and some studies which used peroral cafeine found their subjects (rats or monkeys) sometimes refus~ed the drug even when it was given in fruit juice...After 11 days of exposure to caffeine, play fighting incrzeased in animals that ingested an average of 19.6 or 3’.9 mg/kg cafeine /day but was the...Physiological Psychology, 1965, 59, 18-24. Bossier, J. R. & Simon, P. Influence de la cafeine sur le comportment en situation libre de la sour-is. Archives

  13. A superconducting CW-LINAC for heavy ion acceleration at GSI (United States)

    Barth, Winfried; Aulenbacher, Kurt; Basten, Markus; Dziuba, Florian; Gettmann, Viktor; Miski-Oglu, Maksym; Podlech, Holger; Yaramyshev, Stepan


    Recently the Universal Linear Accelerator (UNILAC) serves as a powerful high duty factor (25%) heavy ion beam accelerator for the ambitious experiment program at GSI. Beam time availability for SHE (Super Heavy Element)-research will be decreased due to the limitation of the UNILAC providing Uranium beams with an extremely high peak current for FAIR simultaneously. To keep the GSI-SHE program competitive on a high level and even beyond, a standalone superconducting continuous wave (100% duty factor) LINAC in combination with the upgraded GSI High Charge State injector is envisaged. In preparation for this, the first LINAC section (financed by HIM and GSI) will be tested with beam in 2017, demonstrating the future experimental capabilities. Further on the construction of an extended cryo module comprising two shorter Crossbar-H cavities is foreseen to test until end of 2017. As a final R&D step towards an entire LINAC three advanced cryo modules, each comprising two CH cavities, should be built until 2019, serving for first user experiments at the Coulomb barrier.

  14. FM-CW radar sensors for vital signs and motor activity monitoring

    Directory of Open Access Journals (Sweden)

    Octavian Adrian Postolache


    Full Text Available The article summarizes on-going research on vital signs and motor activity monitoring based on radar sensors embedded in wheelchairs, walkers and crutches for in home rehabilitation. Embedded sensors, conditioning circuits, real-time platforms that perform data acquisition, auto-identification, primary data processing and data communication contribute to convert daily used objects in home rehabilitation into smart objects that can be accessed by caregivers during the training sessions through human–machine interfaces expressed by the new generation of smart phones or tablet computers running Android OS or iOS operating systems. The system enables the management of patients in home rehabilitation by providing more accurate and up-to-date information using pervasive computing of vital signs and motor activity records.

  15. A Passively Q-Switched, CW-Pumped Fe:ZnSe Laser (United States)


    5023, Dec. 2012. [4] V. Fedorov , D. Martyshkin, M. Mirov, I. S. Moskalev, S. Vasilyev, J. Peppers, et al., “Fe-doped II–VI mid-infrared laser materials...crystal in the 85–255 K temperature range,” Quantum Electron., vol. 35, no. 9, pp. 809–812, 2005. [8] N. Myoung, V. V. Fedorov , S. B. Mirov, and L. E

  16. Discrimination of radiation quality through second harmonic out-of-phase cw-ESR detection. (United States)

    Marrale, Maurizio; Longo, Anna; Brai, Maria; Barbon, Antonio; Brustolon, Marina


    The ability to discriminate the quality of ionizing radiation is important because the biological effects produced in tissue strongly depends on both absorbed dose and linear energy transfer (LET) of ionizing particles. Here we present an experimental electron spin resonance (ESR) analysis aimed at discriminating the effective LETs of various radiation beams (e.g., 19.3 MeV protons, (60)Co photons and thermal neutrons). The measurement of the intensities of the continuous wave spectrometer signal channel first harmonic in-phase and the second harmonic out-of-phase components are used to distinguish the radiation quality. A computational analysis, was carried out to evaluate the dependence of the first harmonic in-phase and second harmonic out-of-phase components on microwave power, modulation amplitude and relaxation times, and highlights that these components could be used to point out differences in the relaxation times. On the basis of this numerical analysis the experimental results are discussed. The methodology described in this study has the potential to provide information on radiation quality.

  17. Uniaxial magnetic anisotropy of cobalt thin films on different substrates using CW-MOKE technique

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, Vijay, E-mail: [Laser Physics Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Mukherjee, C. [Mechanical and Optical Support Section, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Chari, R. [Laser Physics Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Rai, S. [Indus Synchrotron Utilization Division, Raja Ramnna Centre for Advanced Technology, Indore 452013 (India); Bindra, K.S. [Solid State Laser Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Banerjee, A. [BARC training school at RRCAT and Homi Bhabha National Institute, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)


    Cobalt thin films were deposited on GaAs, Si and Glass substrates by RF-magnetron sputtering. The structure was studied using atomic force microscopy, X-ray reflectivity and grazing incidence X-ray diffraction. Magnetic properties were determined with the magneto-optic Kerr effect. The deposited films have in-plane uniaxial anisotropy and after annealing the anisotropy reduces. The reduction in anisotropy may be due to release of stress and the remaining anisotropy after annealing may be due to shape anisotropy of the particulates. - Highlights: • Deposited cobalt thin films on different substrates and annealed at 300 °C. • Characterized as-grown and annealed films by GIXRD, AFM and MOKE. • Uniaxial magnetic anisotropy observed for all the samples. • Decrease in anisotropy on annealing may be due to release of stress during deposition.

  18. Scavenging Iron: A Novel Mechanism of Plant Immunity Activation by Microbial Siderophores1[C][W (United States)

    Aznar, Aude; Chen, Nicolas W.G.; Rigault, Martine; Riache, Nassima; Joseph, Delphine; Desmaële, Didier; Mouille, Grégory; Boutet, Stéphanie; Soubigou-Taconnat, Ludivine; Renou, Jean-Pierre; Thomine, Sébastien; Expert, Dominique; Dellagi, Alia


    Siderophores are specific ferric iron chelators synthesized by virtually all microorganisms in response to iron deficiency. We have previously shown that they promote infection by the phytopathogenic enterobacteria Dickeya dadantii and Erwinia amylovora. Siderophores also have the ability to activate plant immunity. We have used complete Arabidopsis transcriptome microarrays to investigate the global transcriptional modifications in roots and leaves of Arabidopsis (Arabidopsis thaliana) plants after leaf treatment with the siderophore deferrioxamine (DFO). Physiological relevance of these transcriptional modifications was validated experimentally. Immunity and heavy-metal homeostasis were the major processes affected by DFO. These two physiological responses could be activated by a synthetic iron chelator ethylenediamine-di(o-hydroxyphenylacetic) acid, indicating that siderophores eliciting activities rely on their strong iron-chelating capacity. DFO was able to protect Arabidopsis against the pathogenic bacterium Pseudomonas syringae pv tomato DC3000. Siderophore treatment caused local modifications of iron distribution in leaf cells visible by ferrocyanide and diaminobenzidine-H2O2 staining. Metal quantifications showed that DFO causes a transient iron and zinc uptake at the root level, which is presumably mediated by the metal transporter iron regulated transporter1 (IRT1). Defense gene expression and callose deposition in response to DFO were compromised in an irt1 mutant. Consistently, plant susceptibility to D. dadantii was increased in the irt1 mutant. Our work shows that iron scavenging is a unique mechanism of immunity activation in plants. It highlights the strong relationship between heavy-metal homeostasis and immunity. PMID:24501001

  19. Strigolactones Stimulate Internode Elongation Independently of Gibberellins1[C][W (United States)

    de Saint Germain, Alexandre; Ligerot, Yasmine; Dun, Elizabeth A.; Pillot, Jean-Paul; Ross, John J.; Beveridge, Christine A.; Rameau, Catherine


    Strigolactone (SL) mutants in diverse species show reduced stature in addition to their extensive branching. Here, we show that this dwarfism in pea (Pisum sativum) is not attributable to the strong branching of the mutants. The continuous supply of the synthetic SL GR24 via the root system using hydroponics can restore internode length of the SL-deficient rms1 mutant but not of the SL-response rms4 mutant, indicating that SLs stimulate internode elongation via RMS4. Cytological analysis of internode epidermal cells indicates that SLs control cell number but not cell length, suggesting that SL may affect stem elongation by stimulating cell division. Consequently, SLs can repress (in axillary buds) or promote (in the stem) cell division in a tissue-dependent manner. Because gibberellins (GAs) increase internode length by affecting both cell division and cell length, we tested if SLs stimulate internode elongation by affecting GA metabolism or signaling. Genetic analyses using SL-deficient and GA-deficient or DELLA-deficient double mutants, together with molecular and physiological approaches, suggest that SLs act independently from GAs to stimulate internode elongation. PMID:23943865

  20. Rapid spontaneous Raman light sheet microscopy using cw-lasers and tunable filters. (United States)

    Rocha-Mendoza, Israel; Licea-Rodriguez, Jacob; Marro, Mónica; Olarte, Omar E; Plata-Sanchez, Marcos; Loza-Alvarez, Pablo


    We perform rapid spontaneous Raman 2D imaging in light-sheet microscopy using continuous wave lasers and interferometric tunable filters. By angularly tuning the filter, the cut-on/off edge transitions are scanned along the excited Stokes wavelengths. This allows obtaining cumulative intensity profiles of the scanned vibrational bands, which are recorded on image stacks; resembling a spectral version of the knife-edge technique to measure intensity profiles. A further differentiation of the stack retrieves the Raman spectra at each pixel of the image which inherits the 3D resolution of the host light sheet system. We demonstrate this technique using solvent solutions and composites of polystyrene beads and lipid droplets immersed in agar and by imaging the C-H (2800-3100cm(-1)) region in a C. elegans worm. The image acquisition time results in 4 orders of magnitude faster than confocal point scanning Raman systems, allowing the possibility of performing fast spontaneous Raman·3D-imaging on biological samples.

  1. Advancement of High Power Quasi-CW Laser Diode Arrays For Space-based Laser Instruments (United States)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, nathaniel R.; Baggott, Renee S.; Singh, Upendra N.; Kavaya, Michael J.


    Space-based laser and lidar instruments play an important role in NASA s plans for meeting its objectives in both Earth Science and Space Exploration areas. Almost all the lidar instrument concepts being considered by NASA scientist utilize moderate to high power diode-pumped solid state lasers as their transmitter source. Perhaps the most critical component of any solid state laser system is its pump laser diode array which essentially dictates instrument efficiency, reliability and lifetime. For this reason, premature failures and rapid degradation of high power laser diode arrays that have been experienced by laser system designers are of major concern to NASA. This work addresses these reliability and lifetime issues by attempting to eliminate the causes of failures and developing methods for screening laser diode arrays and qualifying them for operation in space.

  2. Power Scaling of CW and Pulsed IR and Mid-IR OPSLs (Postprint) (United States)


    slope efficiency. The device contains ten InGaAs - wells between strain compensating and pump absorbing GaAsP barriers. The barrier thickness has been...VECSELs consist of InGaAs QWs with GaAsP barriers, grown as bottom emitters on a GaAs substrate. Section 2 details our progress in utilizing the quantum ...and experimentally measured (black) reflectivity at 295K. ‘Absorption peak’ marks the wavelength of the quantum well excitonic absorption edge

  3. Polarization-stable dual-color DFB fibre laser system for CW terahertz generation

    DEFF Research Database (Denmark)

    Eichhorn, Finn; Petersen, Jens Engholm; Jepsen, Peter Uhd

    The terahertz, or THz, frequency range represents a gap in technology as well as knowledge in the electromagnetic spectrum. The THz spectral range is here loosely defined as frequencies between 100 GHz and 10 THz. Electromagnetic waves at THz frequencies interact strongly with metals, ceramics...

  4. Reactions of CW Agents HD And GD with the Polymer Fabrics PVAM and CHEMCAT 41 (United States)


    Textile ) is sold by Stedfast (Stedfast, Inc., Granby, Quebec, Canada, or Stedfast USA, Piney Flats, TN). This report includes results on the testing...Multiple NMR spectra were acquired at known time points from the same fabric sample. Textile Properties Current Threshold (Acceptable) Objective (Desired...G-3 History Office U.S. Army RDECOM ATTN: Smart , J. ECBC Technical Library RDCB-DRB-BL ATTN: Foppiano, S. Stein, J

  5. DCS Hydrology Submission for RM-FY09-MI-Alcona County-O-CW (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Hydrology data include spatial datasets and data tables necessary for documenting the hydrologic procedures for estimating flood discharges for a flood insurance...

  6. Physics design of a CW high-power proton Linac for accelerator ...

    Indian Academy of Sciences (India)

    [7] T P Wangler, Principles of RF linear accelerators (John Wiley & Sons Inc., 1998). [8] K Shepard et al, Proceedings of the XIX International Linac Conference (Chicago, Illinois) p. 956. [9] C Pagani et al, Design criteria for elliptical cavities, SRF, 2001. [10] P Singh, S V L S Rao, Rajni Pande, T Basak, Shweta Roy, M Aslam, ...

  7. A simple transformation for converting CW-OSL curves to LM-OSL curves

    DEFF Research Database (Denmark)

    Bulur, E.


    A simple mathematical transformation is introduced to convert from OSL decay curves obtained in the conventional way to those obtained using a linear modulation technique based on a linear increase of the stimulation light intensity during OSL measurement. The validity of the transformation...... was tested by the IR-stimulated luminescence curves from feldspars, recorded using both the conventional and the linear modulation techniques. The transformation was further applied to green-light-stimulated OSL from K and Na feldspars. (C) 2000 Elsevier Science Ltd. All rights reserved....

  8. Precision Locking and Control of CW Lasers in Support of ASCENDS Project (United States)

    National Aeronautics and Space Administration — Vescent Photonics proposes to design and build significantly improved laser frequency locking and control systems that will be suitable for ASCENDS and other NASA...

  9. Design of 57.5 MHz CW RFQ structure for the Rare Isotope ...

    Indian Academy of Sciences (India)

    Input particle velocity. 0.00507 c. Design charge to mass ratio. 28.5/238. Charge to mass ratio of accelerated ions. 28/238; 29/238. Length of the RFQ vanes. 4 m ... describing potential distribution in a cell with given shape of the electrodes are calculated: U(r,ψ,z) .... Transmission as function of the input transverse emittance.

  10. A stepped FM/CW lidar system using a dual parallel Mach-Zehnder modulator (United States)

    Yang, Cheng-hua; Zhang, Yong; Shen, Zhi-qiang; Xu, Lu; Yang, Xu; Liu, Yue-hao; Jin, Chen-fei; Zhao, Yuan


    A stepped frequency-modulated continuous-wave lidar system using a dual parallel Mach-Zehnder modulator with heterodyne detection is demonstrated. The lidar transmitter utilizes a modulation loop circuit composed of an electro-optic dual parallel Mach-Zehnder modulator and a fiber amplifier, as well as a tunable Fabry-Perot filter to generate a bandwidth-enhanced stepped frequency-modulated signal. In addition, a centroid algorithm is used in the receiver to process the signal with both high precision and high accuracy. The simulation results demonstrated that the ranging precision of the proposed lidar was 2.09 cm and the ranging accuracy was 0.16 cm. A validation experiment verified that the data obtained in the simulation had a modulation bandwidth of 4 GHz using a 200-MHz signal source. The improvements resulted in a frequency-modulated continuous-wave lidar system with high precision and accuracy by operating a modulated signal with a wider modulation bandwidth using signal sources with low bandwidth in a low-cost and compact structure.

  11. Development of a 2 MW CW Waterload for Electron Cyclotron Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    R. Lawrence,Ives; Maxwell Mizuhara; George Collins; Jeffrey Neilson; Philipp Borchard


    Calabazas Creek Research, Inc. developed a load capable of continuously dissipating 2 MW of RF power from gyrotrons. The input uses HE11 corrugated waveguide and a rotating launcher to uniformly disperse the power over the lossy surfaces in the load. This builds on experience with a previous load designed to dissipate 1 MW of continuous RF power. The 2 MW load uses more advanced RF dispersion to double the capability in the same size device as the 1 MW load. The new load reduces reflected power from the load to significantly less than 1 %. This eliminates requirements for a preload to capture reflected power. The program updated control electronics that provides all required interlocks for operation and measurement of peak and average power. The program developed two version of the load. The initial version used primarily anodized aluminum to reduce weight and cost. The second version used copper and stainless steel to meet specifications for the ITER reactor currently under construction in France. Tests of the new load at the Japanese Atomic Energy Agency confirmed operation of the load to a power level of 1 MW, which is the highest power currently available for testing the load. Additional tests will be performed at General Atomics in spring 2013. The U.S. ITER organization will test the copper/stainless steel version of the load in December 2012 or early in 2013. Both loads are currently being marketed worldwide.

  12. Modeling and simulation of two-step resonance ionization processes using CW and pulsed lasers

    CERN Document Server

    de Groote, Ruben; Flanagan, Kieran

    This thesis derives and discusses equations that describe the evolution of atomic systems subjected to two monochromatic and coherent radiation fields and treats both continuous and temporally pulsed irradiation. This theoretical description is de- veloped mainly to understand the influence of the photon field intensities on experimental ionization spectra. The primary ap- plication of this theoretical framework is on methods that rely on resonant laser excitation and non-resonant laser ionization to extract information on the hyperfine structure of atomic systems. In particular, qualitative and quantitative discussions on the laser-related changes in hyperfine splitting extracted from ion- ization spectra are presented. Also, a method for increasing the resolution of resonance ionization techniques (potentially up un- til the natural linewidth of the electronic transitions) is discussed and theoretically justified. Both topics are illustrated with exper- imental data.

  13. Novel OSNR Monitoring Technique in Dense WDM Systems using Inherently Generated CW Monitoring Channels

    DEFF Research Database (Denmark)

    Petersen, Martin Nordal


    We present a simple, yet effective OSNR monitoring technique based on an inherent effect in the optical modulator. Highly accurate OSNR monitoring is demonstrated in a 40 Gb/s dense WDM system with 50 GHz channel spacing.......We present a simple, yet effective OSNR monitoring technique based on an inherent effect in the optical modulator. Highly accurate OSNR monitoring is demonstrated in a 40 Gb/s dense WDM system with 50 GHz channel spacing....

  14. SSPARAMA: A Nonlinear, Wave Optics Multipulse (and CW) Steady-State Propagation Code with Adaptive Coordinates (United States)


    provided In the calculation along with a listing of thi, colmputer pro~ gram , DD~M 1473 EDITION 0OP 1 NOV 55 11 ONSOLETE sECUp-RIY CLASSIFICATION OF...transverse scale lengths are adapted to the amount of thermal blooming induced on the pulse train by tlh negativo lensing influence of the heated


    Directory of Open Access Journals (Sweden)

    Zulfaidah Ariany


    Full Text Available This article titled is equipment load factor on cargo ship LCT type by taking a case study on Lestari Abadi ship03, the study aims to predict electric consumption calculation of LCT ship’s type which concerning with thenumber and type of generator; effective and efficience power consumption, safe and effective electric instalationand existing panel. So, minimum required output electric installed to Kapal Lestari Abadi 03 has to 150KW, asspecification performed by caterpillar C9TA 150KW, 188KVA, 1500rpm, 50Hz and 0.8.

  16. Study of a power coupler for superconducting RF cavities used in high intensity proton accelerator; Etude et developpement d'un coupleur de puissance pour les cavites supraconductrices destinees aux accelerateurs de protons de haute intensite

    Energy Technology Data Exchange (ETDEWEB)

    Souli, M


    The coaxial power coupler needed for superconducting RF cavities used in the high energy section of the EUROTRANS driver should transmit 150 kW (CW operation) RF power to the protons beam. The calculated RF and dielectric losses in the power coupler (inner and outer conductor, RF window) are relatively high. Consequently, it is necessary to design very carefully the cooling circuits in order to remove the generated heat and to ensure stable and reliable operating conditions for the coupler cavity system. After calculating all type of losses in the power coupler, we have designed and validated the inner conductor cooling circuit using numerical simulations results. We have also designed and optimized the outer conductor cooling circuit by establishing its hydraulic and thermal characteristics. Next, an experiment dedicated to study the thermal interaction between the power coupler and the cavity was successfully performed at CRYOHLAB test facility. The critical heat load Qc for which a strong degradation of the cavity RF performance was measured leading to Q{sub c} in the range 3 W-5 W. The measured heat load will be considered as an upper limit of the residual heat flux at the outer conductor cold extremity. A dedicated test facility was developed and successfully operated for measuring the performance of the outer conductor heat exchanger using supercritical helium as coolant. The test cell used reproduces the realistic thermal boundary conditions of the power coupler mounted on the cavity in the cryo-module. The first experimental results have confirmed the excellent performance of the tested heat exchanger. The maximum residual heat flux measured was 60 mW for a 127 W thermal load. As the RF losses in the coupler are proportional to the incident RF power, we can deduce that the outer conductor heat exchanger performance is continued up to 800 kW RF power. Heat exchanger thermal conductance has been identified using a 2D axisymmetric thermal model by comparing

  17. Root plasma membrane transporters controlling K+/Na+ homeostasis in salt-stressed bBarley1[C][W

    DEFF Research Database (Denmark)

    Chen, Zhonghua; Pottosin, Igor I.; Cuin, Tracey A.


    are well combined to withstand saline conditions. These mechanisms include: (1) better control of membrane voltage so retaining a more negative membrane potential; (2) intrinsically higher H1 pump activity; (3) better ability of root cells to pump Na1 from the cytosol to the external medium; and (4) higher...

  18. Development of a Time Synchronized CW-Laser Induced Fluorescence Measurement for Quasi-Periodic Oscillatory Plasma Discharges (United States)


    fluorescence signal with oscillating discharge current Two methods considered Boxcar Averager Adds signals in time domain when chopper is open, subtracts... Boxcar Averager Boxcar averager method is more similar to previous studies, including measurements of velocity or energy distributions in: Hall...hold on a Stanford Research Systems SR-250 Boxcar Averager Other SR-250 inputs/settings: Raw emission plus fluorescence from PMT Gate width

  19. CW laser etching of Ba/sub 2/YCu/sub 3/O/sub 7/ films

    Energy Technology Data Exchange (ETDEWEB)

    Fisanick, G.J.; Brasen, D.; Opila, R.; Moore, R.; Mankiewich, P.; Skocpol, W.; Howard, R.E.; Hong, M.; O' Bryan, H.M.


    Laser induced etching has been used to pattern 2000--7000 A thick films of the superconducting perovskite Ba/sub 2/YCu/sub 3/O/sub 7/ and its amorphous precursor. A 5145 A Ar/sup +/ laser beam, focused to a 1.0 beam diameter, with incident intensities of 5--250 mW, scanned at rates of 20--200 in air locally heated the optically absorbing films to induce reaction. Local melting was observed during the laser scans, indicating temperatures in excess of 950/sup 0/C induced in predominantly perovskite phase films. Ablated grooves 1.5--3.0 wide were generated, with destruction of the superconducting phase verified by optical microscopy over a wide range of laser parameters. Scanning Auger and energy dispersive x-ray analyses were used to monitor local chemical composition near the cuts. A wide range of behavior was found for etching of the amorphous precursor films, ranging from simple ablation, to multiple phase segregation, to generation of periodic morphological structure characteristic of local plasma formation in the ejected plume. In contrast, the more optically absorbing perovskite phase showed far less variation in microstructure with laser power, with morphological changes confined to a 0.5 range about the cut. Green and sintered polycrystalline ceramic tapes have also been successfully eteched.

  20. Phase sensitive amplification with noise figure below the 3 dB quantum limit using CW pumped PPLN waveguide. (United States)

    Asobe, Masaki; Umeki, Takeshi; Tadanaga, Osamu


    The noise figure (NF) of a phase sensitive amplifier (PSA) based on a periodically poled LiNbO3 (PPLN) waveguide was evaluated in the optical and electrical domains. Phase sensitive amplification was realized using degenerate parametric amplification in the PPLN waveguide, which was pumped by the second harmonic frequency of the signal. Second harmonic pumping enables direct observation of the intrinsic amplified spontaneous emission (ASE), which determined the NF of the PSA. An NF below the 3 dB quantum limit was obtained by observing the intrinsic ASE. The low NF was also confirmed via the noise floor measurement of a cascaded PSA and erbium doped fiber amplifier in the electrical domain. The PSA was used as a preamplifier for detecting a 40 Gbit/s phase shift keying signal. The low noise characteristics were confirmed by the improved sensitivity.

  1. CW and ultrafast properties of GaAs-AlGaAs core-shell nanowire lasers on silicon (Conference Presentation) (United States)

    Mayer, Benedikt; Koblmueller, Gregor; Regler, Armin; Sterzl, Sabrina; Stettner, Tom; Kaniber, Michael; Lingnau, Benjamin; Lüdge, Kathy; Finley, Jonathan J.


    Wavelength scale coherent optical sources are vital for a wide range of applications in nanophotonics ranging from metrology and sensing to nonlinear frequency generation and optical switching. In these respects, semiconductor nanowires (NWs) are of particular interest since they represent the ultimate limit of downscaling for photonic lasers with dielectric resonators. By virtue of their unique one-dimensional geometry NW-lasers combine ultra-high modal gain, support low-loss guided modes and facilitate low threshold lasing tuneable across the UV, visible and near infra-red spectral regions. Recently, optically pumped NW lasers have been demonstrated at room temperature and they can now be site-selectively integrated onto silicon substrates. While the fundamental carrier relaxation and gain dynamics of NW-lasers have been explored, the coherent dynamics have hitherto received comparatively little attention. In this contribution, we demonstrate that GaAs-AlGaAs core-shell nanowire lasers grown on silicon are capable of emitting pairs of phase-locked picosecond laser pulses when subject to incoherent pulsed optical excitation. By probing the two-pulse interference that emerges within the homogeneously broadened laser emission, we show that pulse pairs remain mutually coherent over timescales extending beyond 30ps, much longer than the emitted laser pulse duration ( 3 ps). Simulations performed by solving the optical Bloch equations produce good quantitative agreement with experiments, revealing how the phase information is stored in the gain medium close to transparency.

  2. Nondestructive evaluation of mechanically stabilized earth walls with frequency-modulated continuous wave (FM-CW) radar. (United States)


    Effective techniques for a nondestructive evaluation of mechanically stabilized earth (MSE) walls during normal operation : or immediately after an earthquake event are yet to be developed. MSE walls often have a rough surface finishing for the : pur...

  3. Power-scalable, polarization-stable, dual-colour DFB fibre laser system for CW terahertz imaging

    DEFF Research Database (Denmark)

    Eichhorn, Finn; Pedersen, Jens Engholm; Jepsen, Peter Uhd

    Imaging with electromagnetic radiation in the terahertz (THz) range has received a large amount of attention during recent years. THz imaging systems have diverse potential application areas such as security screening, medical diagnostics and non-destructive testing. We will discuss a power...

  4. 1.9 W yellow, CW, high-brightness light from a high efficiency semiconductor laser-based system

    DEFF Research Database (Denmark)

    Hansen, Anders Kragh; Christensen, Mathias; Noordegraaf, Danny


    , imaging, flow cytometry, and cancer treatment. However, direct generation of yellow light from semiconductors with sufficient beam quality and power has so far eluded researchers. Meanwhile, tapered semiconductor lasers at near-infrared wavelengths have recently become able to provide neardiffraction...

  5. A tunable CW UV laser with <35 kHz absolute frequency instability for precision spectroscopy of Sr Rydberg states

    CERN Document Server

    Bridge, Elizabeth M; Bounds, Alistair D; Boddy, Danielle; Sadler, Daniel P; Jones, Matthew P A


    We present a solid-state laser system that generates over 200 mW of continuous-wave, narrowband light, tunable between 316.3 nm and 319.3 nm. The laser is based on commercially available fiber amplifiers and optical frequency doubling technology, along with sum frequency generation in a periodically poled stoichiometric lithium tantalate crystal. The laser frequency is stabilized to an atomic-referenced high finesse optical transfer cavity. Using a GPS-referenced optical frequency comb we measure a long term frequency instability of <35 kHz. As an application we perform spectroscopy of Sr Rydberg states from n = 37 - 81, demonstrating mode-hop-free scans of 24 GHz. In a cold atomic sample we measure Doppler-limited linewidths of 350 kHz.

  6. Comparison of Complementary Sequences in Hybrid Phase and Frequency Shift Keying CW Radar Using Periodic Ambiguity Analysis (United States)


    43–45, 1963. [19] B. L. Lewis , F. F. Kretshmer and W. W. Shelton, Aspects of Radar Signal Processing, Norwood, MA: Artech House, 1986. [20] M...Systems Tel Aviv University Tel Aviv, Israel 7. Commander Oscar D. Tascon COTECMAR Cartagena, Colombia

  7. Evaluation of 405nm CW visible blue light as a means of inactivating Tulane Virus on Blueberries (United States)

    Introduction: Visible blue light (405nm) is effective against bacteria but its potential as a nonthermal intervention for viruses on foods, such as berries that are prone to norovirus contamination has not been evaluated. Tulane virus (TV) is now a common human norovirus surrogate that can be propa...

  8. Myocardial temperature distribution under cw Nd:YAG laser irradiation in in vitro and in vivo situations: theory and experiment (United States)

    Splinter, Robert; Littmann, Laszlo; Tuntelder, Jan R.; Svenson, Robert H.; Chuang, Chi Hui; Tatsis, George P.; Semenov, Serguei Y.; Nanney, Glenn A.


    Tissue samples ranging from 2 to 16 mm in thickness were irradiated at 1064 nm with energies ranging from 40 to 2400 J. Coagulation lesions of in vitro and in vivo experiments were subjected to temperature profiling and submitted for histology. Irreversible damage was calculated with the damage integral formalism, following the bioheat equation solved with Monte Carlo computer light-distribution simula-tions. Numerical temperature rise and coagulation depth compared well with the in vitro results. The in vivo data required a change in the optical properties based on integrating sphere measurements for high irradiance to make the experimental and numerical data converge. The computer model has successfully solved several light-tissue interaction situations in which scattering dominates over absorption.

  9. A Nostoc punctiforme Sugar Transporter Necessary to Establish a Cyanobacterium-Plant Symbiosis1[C][W (United States)

    Ekman, Martin; Picossi, Silvia; Campbell, Elsie L.; Meeks, John C.; Flores, Enrique


    In cyanobacteria-plant symbioses, the symbiotic nitrogen-fixing cyanobacterium has low photosynthetic activity and is supplemented by sugars provided by the plant partner. Which sugars and cyanobacterial sugar uptake mechanism(s) are involved in the symbiosis, however, is unknown. Mutants of the symbiotically competent, facultatively heterotrophic cyanobacterium Nostoc punctiforme were constructed bearing a neomycin resistance gene cassette replacing genes in a putative sugar transport gene cluster. Results of transport activity assays using 14C-labeled fructose and glucose and tests of heterotrophic growth with these sugars enabled the identification of an ATP-binding cassette-type transporter for fructose (Frt), a major facilitator permease for glucose (GlcP), and a porin needed for the optimal uptake of both fructose and glucose. Analysis of green fluorescent protein fluorescence in strains of N. punctiforme bearing frt::gfp fusions showed high expression in vegetative cells and akinetes, variable expression in hormogonia, and no expression in heterocysts. The symbiotic efficiency of N. punctiforme sugar transport mutants was investigated by testing their ability to infect a nonvascular plant partner, the hornwort Anthoceros punctatus. Strains that were specifically unable to transport glucose did not infect the plant. These results imply a role for GlcP in establishing symbiosis under the conditions used in this work. PMID:23463784

  10. Conformational Changes Represent the Rate-Limiting Step in the Transport Cycle of Maize SUCROSE TRANSPORTER1[C][W (United States)

    Derrer, Carmen; Wittek, Anke; Bamberg, Ernst; Carpaneto, Armando; Dreyer, Ingo; Geiger, Dietmar


    Proton-driven Suc transporters allow phloem cells of higher plants to accumulate Suc to more than 1 M, which is up to ∼1000-fold higher than in the surrounding extracellular space. The carrier protein can accomplish this task only because proton and Suc transport are tightly coupled. This study provides insights into this coupling by resolving the first step in the transport cycle of the Suc transporter SUT1 from maize (Zea mays). Voltage clamp fluorometry measurements combining electrophysiological techniques with fluorescence-based methods enable the visualization of conformational changes of SUT1 expressed in Xenopus laevis oocytes. Using the Suc derivate sucralose, binding of which hinders conformational changes of SUT1, the association of protons to the carrier could be dissected from transport-associated movements of the protein. These combined approaches enabled us to resolve the binding of protons to the carrier and its interrelationship with the alternating movement of the protein. The data indicate that the rate-limiting step of the reaction cycle is determined by the accessibility of the proton binding site. This, in turn, is determined by the conformational change of the SUT1 protein, alternately exposing the binding pockets to the inward and to the outward face of the membrane. PMID:23964025

  11. Tm3+-doped CW fiber laser based on a highly GeO2-doped dispersion-shifted fiber


    Dvoyrin, Vladislav; Sorokina, Irina T; Mashinsky, Valery M.; Ischakova, Lyudmila D.; Dianov, Evgenii M; Kalashnikov, Valdimir L; Yashkov, Mikhail V.; Khopin, Vladimir F.; Guryanov, Aleksey N.


    A novel all-fiber laser based on a highly GeO2-doped dispersion-shifted Tm-codoped fiber, pumped at 1.56 µm wavelength and lasing at 1.862 µm wavelength with a slope efficiency up to 37% was demonstrated. The single-mode Tm-doped fiber with the 55GeO2-45SiO2 core was fabricated for the first time by MCVD technique. The laser produces spectral side bands, resulting from the four-wave mixing owing to the shift of the zero-dispersion-wavelength of the fiber to the laser wavelength, thus, making ...

  12. Time-dependent analytical thermal model to investigate thermally induced stresses in quasi-CW-pumped laser rods

    CSIR Research Space (South Africa)

    Bernhardi, EH


    Full Text Available One of the main problems that limit the power scaling of diode-end-pumped solid-state lasers is the generation of heat inside the laser gain medium which can ultimately cause fracture. In this paper a time-dependent analytical thermal model...

  13. Laser Spectroscopy of CW Optical-Optical Double Resonance and All-Optical Triple Resonance in Diatomic Sodium Molecules (United States)

    Whang, Thou-Jen

    The sodium dimer is one of the most interesting molecules studied since the last century due to its simplicity both in theory and in experiment. In this study the Na _2 2^1 Pi _ {rm g} state has been extensively studied through the intermediate A^1Sigma _sp{rm u}{+} state by optical-optical double resonance (OODR) spectroscopy and the 2^3Delta_{rm g}, 3^3Sigma_sp {rm g}{+}, 1^3 Delta_{rm g}, 2 ^3Pi_{rm g}, and 4^3Sigma_sp{rm g}{+} states have been either newly observed or extensively studied through the intermediate perturbed A^1Sigma_sp{ rm u}{+} ~ b^3Pi_{rm u}nuclear hyperfine structures. For these states, most of the Dunham coefficients, RKR potential curves, and absolute vibrational numberings have been determined and are presented in tables and figures. The second part of this work is the spectroscopic study in the Na_2 b^3 Pi_{rm u} state by the perturbation-facilitated optical-optical double resonance -stimulated emission pumping technique (PFOODR-SEP). Because of the spin-forbidden transition from the thermally populated ground state to the b^3Pi_ {rm u} state, it is difficult to investigate the b state except for those levels perturbed by the A^1Sigma_sp{rm u}{+} state due to the spin-orbit interaction. In this study the b^3Pi _{Omega u} state (Omega = 0, 1, and 2 components) has been reached in the region of lower vibrational levels and of higher vibrational levels, most of which are unperturbed. The resultant Dunham coefficients have been obtained from deperturbed molecular constants of each vibrational level. The value of this newly developed technique (all-optical triple resonance) is, however, not only that it can detect unperturbed levels in the b state inaccessible from single photon transition but also that it can generally reduce restrictions imposed by the Franck-Condon principle or by symmetry selection rules. Thus, for example, one can now investigate the long-range molecules such as in the A^1 Sigma_sp{rm u}{+} state and state-selected photodissociation of the B^1Pi_{rm u} state in the alkali dimer systems.

  14. The Cotton Transcription Factor TCP14 Functions in Auxin-Mediated Epidermal Cell Differentiation and Elongation1[C][W (United States)

    Wang, Miao-Ying; Zhao, Pi-Ming; Cheng, Huan-Qing; Han, Li-Bo; Wu, Xiao-Min; Gao, Peng; Wang, Hai-Yun; Yang, Chun-Lin; Zhong, Nai-Qin; Zuo, Jian-Ru; Xia, Gui-Xian


    Plant-specific TEOSINTE-BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors play crucial roles in development, but their functional mechanisms remain largely unknown. Here, we characterized the cellular functions of the class I TCP transcription factor GhTCP14 from upland cotton (Gossypium hirsutum). GhTCP14 is expressed predominantly in fiber cells, especially at the initiation and elongation stages of development, and its expression increased in response to exogenous auxin. Induced heterologous overexpression of GhTCP14 in Arabidopsis (Arabidopsis thaliana) enhanced initiation and elongation of trichomes and root hairs. In addition, root gravitropism was severely affected, similar to mutant of the auxin efflux carrier PIN-FORMED2 (PIN2) gene. Examination of auxin distribution in GhTCP14-expressing Arabidopsis by observation of auxin-responsive reporters revealed substantial alterations in auxin distribution in sepal trichomes and root cortical regions. Consistent with these changes, expression of the auxin uptake carrier AUXIN1 (AUX1) was up-regulated and PIN2 expression was down-regulated in the GhTCP14-expressing plants. The association of GhTCP14 with auxin responses was also evidenced by the enhanced expression of auxin response gene IAA3, a gene in the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) family. Electrophoretic mobility shift assays showed that GhTCP14 bound the promoters of PIN2, IAA3, and AUX1, and transactivation assays indicated that GhTCP14 had transcription activation activity. Taken together, these results demonstrate that GhTCP14 is a dual-function transcription factor able to positively or negatively regulate expression of auxin response and transporter genes, thus potentially acting as a crucial regulator in auxin-mediated differentiation and elongation of cotton fiber cells. PMID:23715527

  15. Temporal characterization of plasma cw high-power CO2 laser-matter interaction: contribution to the welding process control (United States)

    Engel, Thierry; Kane, M.; Fontaine, Joel


    During high-power laser welding, gas ionization occurs above the sample. The resulting plasma ignition threshold is related to ionization potential of metallic vapors from the sample, and shielding gases used in the process. In this work, we have characterized the temporal behavior of the radiation emitted by the plasma during laser welding in order to relate the observed signals to the process parameters.

  16. Optical Sensitizing of Photorefractive Sn2P2S6 With CW and Pulsed Pre-Exposure (Preprint) (United States)


    nonlinear scattering, and recovery to the initial transmission, respectively. 1 Distribution A. Approved for public release (PA): distribution... antimony doping. The second conclusion is in line with our published data on the identification of secondary centers in Sn2P2S6:Sb using the EPR...optical sensitizing of photorefraction in antimony doped Sn2P2S6 crystals. AKNOWLEDGMENTS The financial support of the European Office of

  17. CW-THz vector spectroscopy and imaging system based on 1.55-µm fiber-optics. (United States)

    Kim, Jae-Young; Song, Ho-Jin; Yaita, Makoto; Hirata, Akihiko; Ajito, Katsuhiro


    We present a continuous-wave terahertz (THz) vector spectroscopy and imaging system based on a 1.5-µm fiber optic uni-traveling-carrier photodiode and InGaAs photo-conductive receiver. Using electro-optic (EO) phase modulators for THz phase control with shortened optical paths, the system achieves fast vector measurement with effective phase stabilization. Dynamic ranges of 100 dB · Hz and 75 dB · Hz at 300 GHz and 1 THz, and phase stability of 1.5° per minute are obtained. With the simultaneous measurement of absorbance and relative permittivity, we demonstrate non-destructive analyses of pharmaceutical cocrystals inside tablets within a few minutes.

  18. Generation of sub-100-fs pulses from a CW mode-locked chromium-doped forsterite laser (United States)

    Seas, A.; Petricevic, V.; Alfano, R. R.


    Generation of femtosecond pulses from a continuous-wave mode-locked chromium-doped forsterite laser is reported. The forsterite laser was actively mode locked by using an acoustooptic modulator operating at 78 MHz with two Brewster high-dispersion glass prisms for intracavity chirp compensation. Transform-limited sub-100-fs pulses were routinely generated in the TEM(00) mode with 85 mW of continuous power (with 1 percent output coupler), tunable over 1230-1280 nm. The shortest pulses measured had a 60-fs pulse width.

  19. Analysis of the feed-forward method for the referencing of a CW laser to a frequency comb. (United States)

    Gatti, D; Sala, T; Gambetta, A; Coluccelli, N; Conti, G Nunzi; Galzerano, G; Laporta, P; Marangoni, M


    We report on a comprehensive theoretical and experimental analysis of the feed-forward method for external frequency stabilization of a continuous wave laser against a frequency comb. Application of the method to a distributed feedback diode laser at 1.55 μm allows line narrowing from 800 to 10 kHz, with frequency noise reduction by more than 2 decades up to a Fourier frequency of 100 kHz and a maximum control bandwidth of 0.8 MHz. The results are consistent with a relative phase fluctuation of 1.4 rad rms, as limited by uncompensated high-frequency noise of the slave laser.

  20. Simultaneous measurements of velocity, temperature, and pressure using rapid CW wavelength-modulation laser-induced fluorescence of OH (United States)

    Chang, A. Y.; Battles, B. E.; Hanson, R. K.


    In high speed flows, laser induced fluorescence (LIF) on Doppler shifted transitions is an attractive technique for velocity measurement. LIF velocimetry was applied to combined single-point measurements of velocity, temperature, and pressure and 2-D imaging of velocity and pressure. Prior to recent research using NO, LIF velocimetry in combustion related flows relied largely on the use of seed molecules. Simultaneous, single-point LIF measurements is reported of velocity, temperature, and pressure using the naturally occurring combustion species OH. This experiment is an extension of earlier research in which a modified ring dye laser was used to make time resolved temperature measurements behind reflected shock waves by using OH absorption an in postflame gases by using OH LIF. A pair of fused-silica rhombs mounted on a single galvanonmeter in an intracavity-doubled Spectra-Physics 380 ring laser permit the UV output to be swept continuously over a few wave numbers at an effective frequency of 3kHz.

  1. Military Use of Drugs Not Yet Approved by the FDA for CW/BW Defense. Lessons from the Gulf War

    National Research Council Canada - National Science Library

    Rettig, Richard


    .... It deals with the Interim Rule, adopted in December 1990, which established the authority of the Commissioner of Food and Drugs to waive informed consent for using investigational drugs in certain...

  2. Fabrication and stability of fiber bragg gratings for WDM applications using a 266 nm cw-laser

    DEFF Research Database (Denmark)

    Deyerl, Hans-Jürgen; Sørensen, Henrik Rokkjær; Jensen, Jesper Bo Damm


    Diode pumped continuous wave all solid state UV-lasers operating at 266 nm offer an interesting alternative to frequency doubled argon ion lasers. We compare photosensitivity, UV-writing of Bragg gratings and thermal decay at 244, 257 and 266 nm....

  3. Quartz-enhanced photoacoustic spectroscopy-based sensor system for sulfur dioxide detection using a CW DFB-QCL (United States)

    Waclawek, J. P.; Lewicki, R.; Moser, H.; Brandstetter, M.; Tittel, F. K.; Lendl, B.


    Sulfur dioxide (SO2) trace gas detection based on quartz-enhanced photoacoustic spectroscopy (QEPAS) using a continuous wave, distributed feedback quantum cascade laser operating at 7.24 μm was performed. Influence of water vapor addition on monitored QEPAS SO2 signal was also investigated. A normalized noise equivalent absorption coefficient of NNEA (1 σ) = 1.21 × 10-8 cm-1 W Hz-1/2 was obtained for the ν 3 SO2 line centered at 1,380.93 cm-1 when the gas sample was moisturized with 2.3 % H2O. This corresponds to a minimum detection limit (1 σ) of 63 parts per billion by volume for a 1 s lock-in time constant.

  4. Monolithic ring resonator with PPLN crystal for efficient cw SHG of 976 nm emitted by a diode laser (United States)

    Skoczowsky, Danilo; Jechow, Andreas; Stürmer, Herbert; Poßner, Torsten; Stry, Sandra; Sacher, Joachim; Menzel, Ralf


    A new setup for efficient blue light generation that consists of two passively coupled optical resonators is presented. The first resonator is based on a broad area laser diode (BAL) in a Littrow external cavity with a special off-axis design. This external cavity diode laser provides more than 450 mW diffraction limited and narrow bandwidth emission at 976 nm. A compact cavity design with 40 mm length could be realized. The second resonator is a monolithic high finesse ring cavity containing a 10 mm bulk periodically poled lithium niobate (PPLN) crystal for resonant second harmonic generation. This ring resonator consists of four small mirrors with appropriate reflectivities and two GRIN lenses for stability reasons. All parts of this ring cavity are mounted monolithically on a glass substrate with a size of 19.5 mm x 8.5 mm. First experiments showed good passive matching of both cavities without any active closed-loop control. With this setup efficient SHG was achieved. A maximum optical output power of 70 mW blue light at 488 nm was obtained. The conversion efficiency was better than 15%.

  5. QEPAS based detection of broadband absorbing molecules using a widely tunable, cw quantum cascade laser at 8.4 mum. (United States)

    Lewicki, Rafal; Wysocki, Gerard; Kosterev, Anatoliy A; Tittel, Frank K


    Detection of molecules with wide unresolved rotationa-lvibrational absorption bands is demonstrated by using Quartz Enhanced Photoacoustic Spectroscopy and an amplitude modulated, high power, thermoelectrically cooled quantum cascade laser operating at 8.4 mum in an external cavity configuration. The laser source exhibits single frequency tuning of 135 cm-1 with a maximum optical output power of 50 mW. For trace-gas detection of Freon 125 (pentafluoroethane) at 1208.62 cm-1 a normalized noise equivalent absorption coefficient of NNEA=2.64x10(-9) cm?(-1)W/Hz(1/2)was obtained. Noise equivalent sensitivity at ppbv level as well as spectroscopic chemical analysis of a mixture of two broadband absorbers (Freon 125 and acetone) with overlapping absorption spectra were demonstrated.

  6. N-Acyl-Homoserine Lactone Confers Resistance toward Biotrophic and Hemibiotrophic Pathogens via Altered Activation of AtMPK61[C][W (United States)

    Schikora, Adam; Schenk, Sebastian T.; Stein, Elke; Molitor, Alexandra; Zuccaro, Alga; Kogel, Karl-Heinz


    Pathogenic and symbiotic bacteria rely on quorum sensing to coordinate the collective behavior during the interactions with their eukaryotic hosts. Many Gram-negative bacteria use N-acyl-homoserine lactones (AHLs) as signals in such communication. Here we show that plants have evolved means to perceive AHLs and that the length of acyl moiety and the functional group at the γ position specify the plant’s response. Root treatment with the N-3-oxo-tetradecanoyl-L-homoserine lactone (oxo-C14-HSL) reinforced the systemic resistance to the obligate biotrophic fungi Golovinomyces orontii in Arabidopsis (Arabidopsis thaliana) and Blumeria graminis f. sp. hordei in barley (Hordeum vulgare) plants. In addition, oxo-C14-HSL-treated Arabidopsis plants were more resistant toward the hemibiotrophic bacterial pathogen Pseudomonas syringae pv tomato DC3000. Oxo-C14-HSL promoted a stronger activation of mitogen-activated protein kinases AtMPK3 and AtMPK6 when challenged with flg22, followed by a higher expression of the defense-related transcription factors WRKY22 and WRKY29, as well as the PATHOGENESIS-RELATED1 gene. In contrast to wild-type Arabidopsis and mpk3 mutant, the mpk6 mutant is compromised in the AHL effect, suggesting that AtMPK6 is required for AHL-induced resistance. Results of this study show that AHLs commonly produced in the rhizosphere are crucial factors in plant pathology and could be an agronomic issue whose full impact has to be elucidated in future analyses. PMID:21940998

  7. Creating Minimum Harm Practice (MiHaP: a concept for continuous improvement [v1; ref status: indexed,

    Directory of Open Access Journals (Sweden)

    Ranjit Singh


    Full Text Available The author asks for the attention of leaders and all other stakeholders to calls of the World Health Organization (WHO, the Institute of Medicine (IOM, and the UK National Health Service (NHS to promote continuous learning to reduce harm to patients. This paper presents a concept for structured bottom-up methodology that enables and empowers all stakeholders to identify, prioritize, and address safety challenges. This methodology takes advantage of the memory of the experiences of all persons involved in providing care. It respects and responds to the uniqueness of each setting by empowering and motivating all team members to commit to harm reduction. It is based on previously published work on “Best Practices Research (BPR” and on “Systematic Appraisal of Risk and Its Management for Error Reduction (SARAIMER”. The latter approach, has been shown by the author (with Agency for Healthcare Research and Quality (AHRQ support, to reduce adverse events and their severity through empowerment, ownership and work satisfaction. The author puts forward a strategy for leaders to implement, in response to national and international calls for Better health, Better care, and Better value (the 3B’s of healthcare in the US Patient Protection and Affordable Care Act.  This is designed to enable and implement “A promise to learn- a commitment to act”.  AHRQ has recently published “A Toolkit for Rapid-Cycle Patient Safety and Quality Improvement” that includes an adapted version of SARAIMER.

  8. Dual-wavelength mid-infrared CW and Q-switched laser in diode end-pumped Tm,Ho:GdYTaO4 crystal (United States)

    Wang, Beibei; Gao, Congcong; Dou, Renqin; Nie, Hongkun; Sun, Guihua; Liu, Wenpeng; Yu, Haijuan; Wang, Guoju; Zhang, Qingli; Lin, Xuechun; He, Jingliang; Wang, Wenjun; Zhang, Bingyuan


    Dual-wavelength continuous-wave and Q-switched lasers are demonstrated in a Tm,Ho:GdYTaO4 crystal under 790 nm laser diode end pumping for the first time to the best of our knowledge. The laser operates with a dual wavelength at 1949.677 nm and 2070 nm for continuous-wave with a spacing of about 120 nm. The maximum output power is 0.332 W with a pump power of 3 W. By using graphene as the saturable absorber, a passively Q-switched operation is performed with a dual-wavelength at 1950.323 nm and 2068.064 nm with a wavelength interval of about 118 nm. The maximum average output power of the Q-switched laser goes up to 200 mW with a minimum pulse duration of 1.2 µs and a maximum repetition rate of 34.72 kHz.

  9. Random-modulation CW lidar system for space-borne carbon dioxide remote sensing based on a high-brightness semiconductor laser (United States)

    Esquivias, I.; Pérez-Serrano, A.; Tijero, J. M. G.; Faugeron, M.; Van Dijk, F.; Krakowski, M.; Kochem, G.; Traub, M.; Barbero, J.; Adamiec, P.; Ai, X.; Rarity, J.; Quatrevalet, M.; Ehret, G.


    The accurate determination of the atmospheric distribution of carbon dioxide (CO2) on planetary scale is a key requirement for setting up modeling tools able to make reliable predictions of Earth climate dynamics which are essential for the understanding of such important issues as climate change and global warming. Nowadays, the concentrations of CO2 are mainly measured in-situ at a number of surface stations that are unevenly distributed over the planet. Air-borne and space-borne missions have the potential to provide a denser and better distributed set of observations to complement those provided by the surface network.

  10. Terpene Down-Regulation in Orange Reveals the Role of Fruit Aromas in Mediating Interactions with Insect Herbivores and Pathogens1[C][W (United States)

    Rodríguez, Ana; San Andrés, Victoria; Cervera, Magdalena; Redondo, Ana; Alquézar, Berta; Shimada, Takehiko; Gadea, José; Rodrigo, María Jesús; Zacarías, Lorenzo; Palou, Lluís; López, María M.; Castañera, Pedro; Peña, Leandro


    Plants use volatile terpene compounds as odor cues for communicating with the environment. Fleshy fruits are particularly rich in volatiles that deter herbivores and attract seed dispersal agents. We have investigated how terpenes in citrus fruit peels affect the interaction between the plant, insects, and microorganisms. Because limonene represents up to 97% of the total volatiles in orange (Citrus sinensis) fruit peel, we chose to down-regulate the expression of a limonene synthase gene in orange plants by introducing an antisense construct of this gene. Transgenic fruits showed reduced accumulation of limonene in the peel. When these fruits were challenged with either the fungus Penicillium digitatum or with the bacterium Xanthomonas citri subsp. citri, they showed marked resistance against these pathogens that were unable to infect the peel tissues. Moreover, males of the citrus pest medfly (Ceratitis capitata) were less attracted to low limonene-expressing fruits than to control fruits. These results indicate that limonene accumulation in the peel of citrus fruit appears to be involved in the successful trophic interaction between fruits, insects, and microorganisms. Terpene down-regulation might be a strategy to generate broad-spectrum resistance against pests and pathogens in fleshy fruits from economically important crops. In addition, terpene engineering may be important for studying the basic ecological interactions between fruits, herbivores, and pathogens. PMID:21525333

  11. Arabidopsis snc2-1D Activates Receptor-Like Protein-Mediated Immunity Transduced through WRKY70[C][W (United States)

    Zhang, Yaxi; Yang, Yuanai; Fang, Bin; Gannon, Patrick; Ding, Pingtao; Li, Xin; Zhang, Yuelin


    Plant immune receptors belonging to the receptor-like protein (RLP) family contain extracellular leucine-rich repeats (LRRs) and a short cytoplasmic tail linked by a single transmembrane motif. Here, we report the identification of snc2-1D (for suppressor of npr1-1, constitutive 2), a semidominant Arabidopsis thaliana mutant with constitutively activated defense responses. Map-based cloning of snc2-1D showed that it encodes an RLP. The point mutation in snc2-1D leads to substitution of the second Gly for Arg in the conserved GXXXG motif of the transmembrane helix, suggesting that this residue is important for negative regulation of the protein. Epistasis analysis revealed that the snc2-1D mutant phenotype is not affected by mutations in genes known to be required for the nucleotide binding (NB)-LRR Resistance (R) protein signaling. A suppressor screen of snc2-1D was performed, and map-based cloning of one suppressor revealed that mutations in WRKY70 suppress the constitutive defense responses in snc2-1D, suggesting that WRKY70 functions downstream of snc2-1D. The identification of snc2-1D provides us with a unique system for genetic analysis of resistance pathways downstream of RLPs, which may be distinct from those downstream of NB-LRR type R proteins. PMID:20841424

  12. Simple model, including recoil, for the brightness of sodium guide stars created from CW single frequency fasors and comparison to measurements (United States)

    Hillman, Paul D.; Drummond, Jack D.; Denman, Craig A.; Fugate, Robert Q.


    Using a stable single frequency (Δυ fasor we have characterized the guide star radiance under several conditions, including routinely measuring the radiance at various launch powers and simultaneously illuminating the same spot with a second fasor with a range of different frequency separations. Making use of sodium's hyperfine energy diagram and allowed transitions it is shown that some transitions do not contribute to the radiance after a short time period thus greatly reducing the number of states whose populations need to be tracked in a simple rate equation model. An offshoot of this view is the importance of the pump source's spectral content for efficient sodium scattering. Accounting for atomic recoil, which causes atoms to be Doppler shifted out of resonance, we obtain model curves for photon return flux versus launch power for both linear and circular polarization, both agree with measurements; the only free parameter being the sodium column density on the single night both sets of data were taken. We attempted to measure the sodium velocity distribution due to recoil using two Fasors in a pump-probe arrangement. We have measured some subtle phenomena that this simple model does not explain and these will be discussed. These may imply the importance of understanding the collision rates for sodium atoms to re-equilibrate through velocity changing collisions, spin relaxation and coherent beam propagation under various atmospheric conditions.

  13. Ultraviolet-B-Induced Stomatal Closure in Arabidopsis Is Regulated by the UV RESISTANCE LOCUS8 Photoreceptor in a Nitric Oxide-Dependent Mechanism1[C][W (United States)

    Tossi, Vanesa; Lamattina, Lorenzo; Jenkins, Gareth I.; Cassia, Raúl O.


    UV RESISTANCE LOCUS8 (UVR8) signaling involves CONSTITUTIVELY PHOTOMORPHOGENIC1, the ELONGATED HYPOCOTYL5 (HY5) transcription factor, and the closely related HY5 HOMOLOG. Some UV-B responses mediated by UVR8 are also regulated by nitric oxide (NO), a bioactive molecule that orchestrates a wide range of processes in plants. In this study, we investigated the participation of the UVR8 pathway and its interaction with NO in UV-B-induced stomatal movements in Arabidopsis (Arabidopsis thaliana). Stomata in abaxial epidermal strips of Arabidopsis ecotype Landsberg erecta closed in response to increasing UV-B fluence rates, with maximal closure after 3-h exposure to 5.46 μmol m–2 s–1 UV-B. Both hydrogen peroxide (H2O2) and NO increased in response to UV-B, and stomatal closure was maintained by NO up to 24 h after the beginning of exposure. Stomata of plants expressing bacterial NO dioxygenase, which prevents NO accumulation, did not close in response to UV-B, although H2O2 still increased. When the uvr8-1 null mutant was exposed to UV-B, stomata remained open, irrespective of the fluence rate. Neither NO nor H2O2 increased in stomata of the uvr8-1 mutant. However, the NO donor S-nitrosoglutathione induced closure of uvr8-1 stomata to the same extent as in the wild type. Experiments with mutants in UVR8 signaling components implicated CONSTITUTIVELY PHOTOMORPHOGENIC1, HY5, and HY5 HOMOLOG in UV-B-induced stomatal closure. This research provides evidence that the UVR8 pathway regulates stomatal closure by a mechanism involving both H2O2 and NO generation in response to UV-B exposure. PMID:24586043

  14. Insect abundance over Chinese rice fields in relation to environmental parameters, studied with a polarization-sensitive CW near-IR lidar system (United States)

    Zhu, Shiming; Malmqvist, Elin; Li, Wansha; Jansson, Samuel; Li, Yiyun; Duan, Zheng; Svanberg, Katarina; Feng, Hongqiang; Song, Ziwei; Zhao, Guangyu; Brydegaard, Mikkel; Svanberg, Sune


    Effective monitoring of flying insects is of major societal importance in view of the role of insects as indispensable pollinators, destructive disease vectors and economically devastating agricultural pests. The present paper reports on monitoring of flying agricultural pests using a continuous-wave lidar system in a rice-field location in Southern China. Using a Scheimpflug arrangement, range resolution over several 100 m long observational paths was achieved. The system operates with two perpendicularly polarized near-infrared lasers, which are activated intermittently, and back-scattered radiation from insects was recorded by a linear array detector placed after a linear polarizer. Our polarization sensitive system was used to monitor the flying insect diurnal activity and also the influence of changes in weather conditions, e.g., the occurrence of rain. Activity strongly peaked at dusk and rose again, although to a lower extent, just before dawn. At the onset of rainfall, a strong increase in insect counts occurred which was interpreted as the rain-induced bringing down of high-altitude migrant insects.

  15. CW DFB RT diode laser-based sensor for trace-gas detection of ethane using a novel compact multipass gas absorption cell (United States)

    Krzempek, Karol; Jahjah, Mohammad; Lewicki, Rafał; Stefański, Przemysław; So, Stephen; Thomazy, David; Tittel, Frank K.


    The development of a continuous wave, thermoelectrically cooled (TEC), distributed feedback diode laser-based spectroscopic trace-gas sensor for ultra-sensitive and selective ethane (C2H6) concentration measurements is reported. The sensor platform used tunable diode laser absorption spectroscopy (TDLAS) and wavelength modulation spectroscopy as the detection technique. TDLAS was performed using an ultra-compact 57.6 m effective optical path length innovative spherical multipass cell capable of 459 passes between two mirrors separated by 12.5 cm and optimized for the 2.5-4 μm range TEC mercury-cadmium-telluride detector. For an interference-free C2H6 absorption line located at 2,976.8 cm-1, a 1 σ minimum detection limit of 740 pptv with a 1 s lock-in amplifier time constant was achieved.

  16. A Change in SHATTERPROOF Protein Lies at the Origin of a Fruit Morphological Novelty and a New Strategy for Seed Dispersal in Medicago Genus1[C][W (United States)

    Fourquin, Chloé; del Cerro, Carolina; Victoria, Filipe C.; Vialette-Guiraud, Aurélie; de Oliveira, Antonio C.; Ferrándiz, Cristina


    Angiosperms are the most diverse and numerous group of plants, and it is generally accepted that this evolutionary success owes in part to the diversity found in fruits, key for protecting the developing seeds and ensuring seed dispersal. Although studies on the molecular basis of morphological innovations are few, they all illustrate the central role played by transcription factors acting as developmental regulators. Here, we show that a small change in the protein sequence of a MADS-box transcription factor correlates with the origin of a highly modified fruit morphology and the change in seed dispersal strategies that occurred in Medicago, a genus belonging to the large legume family. This protein sequence modification alters the functional properties of the protein, affecting the affinities for other protein partners involved in high-order complexes. Our work illustrates that variation in coding regions can generate evolutionary novelties not based on gene duplication/subfunctionalization but by interactions in complex networks, contributing also to the current debate on the relative importance of changes in regulatory or coding regions of master regulators in generating morphological novelties. PMID:23640757

  17. Tunable All-Optical Wavelength Conversion Based on Cascaded SHG/DFG in a Ti:PPLN Waveguide Using a Single CW Control Laser

    DEFF Research Database (Denmark)

    Hu, Hao; Nouroozi, Rahman; Wang, Wenrui


    Tunable all-optical wavelength conversion (AOWC) of a 40-Gb/s RZ-OOK data signal based on cascaded second-harmonic generation (SHG) and difference-frequency generation (DFG) in a Ti:PPLN waveguide is demonstrated. Error-free performances with negligible power penalty are achieved for the wavelength...

  18. Arabidopsis Class I and Class II TCP Transcription Factors Regulate Jasmonic Acid Metabolism and Leaf Development Antagonistically1[C][W (United States)

    Danisman, Selahattin; van der Wal, Froukje; Dhondt, Stijn; Waites, Richard; de Folter, Stefan; Bimbo, Andrea; van Dijk, Aalt DJ; Muino, Jose M.; Cutri, Lucas; Dornelas, Marcelo C.; Angenent, Gerco C.; Immink, Richard G.H.


    TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR1 (TCP) transcription factors control developmental processes in plants. The 24 TCP transcription factors encoded in the Arabidopsis (Arabidopsis thaliana) genome are divided into two classes, class I and class II TCPs, which are proposed to act antagonistically. We performed a detailed phenotypic analysis of the class I tcp20 mutant, showing an increase in leaf pavement cell sizes in 10-d-old seedlings. Subsequently, a glucocorticoid receptor induction assay was performed, aiming to identify potential target genes of the TCP20 protein during leaf development. The LIPOXYGENASE2 (LOX2) and class I TCP9 genes were identified as TCP20 targets, and binding of TCP20 to their regulatory sequences could be confirmed by chromatin immunoprecipitation analyses. LOX2 encodes for a jasmonate biosynthesis gene, which is also targeted by class II TCP proteins that are under the control of the microRNA JAGGED AND WAVY (JAW), although in an antagonistic manner. Mutation of TCP9, the second identified TCP20 target, resulted in increased pavement cell sizes during early leaf developmental stages. Analysis of senescence in the single tcp9 and tcp20 mutants and the tcp9tcp20 double mutants showed an earlier onset of this process in comparison with wild-type control plants in the double mutant only. Both the cell size and senescence phenotypes are opposite to the known class II TCP mutant phenotype in JAW plants. Altogether, these results point to an antagonistic function of class I and class II TCP proteins in the control of leaf development via the jasmonate signaling pathway. PMID:22718775

  19. Plantation Forestry under Global Warming: Hybrid Poplars with Improved Thermotolerance Provide New Insights on the in Vivo Function of Small Heat Shock Protein Chaperones1[C][W (United States)

    Merino, Irene; Contreras, Angela; Jing, Zhong-Ping; Gallardo, Fernando; Cánovas, Francisco M.; Gómez, Luis


    Climate-driven heat stress is a key factor affecting forest plantation yields. While its effects are expected to worsen during this century, breeding more tolerant genotypes has proven elusive. We report here a substantial and durable increase in the thermotolerance of hybrid poplar (Populus tremula × Populus alba) through overexpression of a major small heat shock protein (sHSP) with convenient features. Experimental evidence was obtained linking protective effects in the transgenic events with the unique chaperone activity of sHSPs. In addition, significant positive correlations were observed between phenotype strength and heterologous sHSP accumulation. The remarkable baseline levels of transgene product (up to 1.8% of total leaf protein) have not been reported in analogous studies with herbaceous species. As judged by protein analyses, such an accumulation is not matched either by endogenous sHSPs in both heat-stressed poplar plants and field-grown adult trees. Quantitative real time-polymerase chain reaction analyses supported these observations and allowed us to identify the poplar members most responsive to heat stress. Interestingly, sHSP overaccumulation was not associated with pleiotropic effects that might decrease yields. The poplar lines developed here also outperformed controls under in vitro and ex vitro culture conditions (callus biomass, shoot production, and ex vitro survival), even in the absence of thermal stress. These results reinforce the feasibility of improving valuable genotypes for plantation forestry, a field where in vitro recalcitrance, long breeding cycles, and other practical factors constrain conventional genetic approaches. They also provide new insights into the biological functions of the least understood family of heat shock protein chaperones. PMID:24306533

  20. Development, preclinical safety, formulation, and stability of clinical grade bevacizumab-800CW, a new near infrared fluorescent imaging agent for first in human use

    NARCIS (Netherlands)

    ter Weele, Eva J.; Terwisscha Van Scheltinga, Anton; Linssen, Matthijs D.; Nagengast, Wouter B.; Lindner, Ingo; Jorritsma-Smit, Annelies; Vries, de Elisabeth G. E.; Kosterink, Jos G. W.; Lub-de Hooge, Marjolijn N.

    There is a dire need for better visualization of cancer and analysis of specific targets in vivo. Molecular imaging with fluorescence is gaining more and more attention, as it allows detection of these targets and has advantages over radioactivity, such as no radiation dose, and lower costs. A key

  1. Deciphering the Physalis floridana Double-Layered-Lantern1 Mutant Provides Insights into Functional Divergence of the GLOBOSA Duplicates within the Solanaceae1[C][W (United States)

    Zhang, Ji-Si; Li, Zhichao; Zhao, Jing; Zhang, Shaohua; Quan, Hui; Zhao, Man; He, Chaoying


    Physalis spp. develop the “Chinese lantern” trait, also known as inflated calyx syndrome, that is a morphological novelty. Here, we identified the double-layered-lantern1 (doll1) mutant, a recessive and monofactorial mutation, in Physalis floridana; its corolla and androecium were transformed into the calyx and gynoecium, respectively. Two GLOBOSA-like MADS-box paralogous genes PFGLO1 and PFGLO2 were found in Physalis floridana, while the mutated phenotype was cosegregated with a large deletion harboring PFGLO1 and was complemented by the PFGLO1 genomic locus in transgenic plants, and severe PFGLO1 knockdowns phenocopied doll1. Thus, DOLL1 encodes the PFGLO1 protein and plays a primary role in determining corolla and androecium identity. However, specific PFGLO2 silencing showed no homeotic variation but rather affected pollen maturation. The two genes featured identical floral expression domains, but the encoding proteins shared 67% identity in sequences. PFGLO1 was localized in the nucleus when expressed in combination with a DEFICIENS homolog from Physalis floridana, whereas PFGLO2 was imported to the nucleus on its own. The two proteins were further found to have evolved different interacting partners and regulatory patterns, supporting the hypothesis that PFGLO2 is functionally separated from organ identity. Such a divergent pattern of duplicated GLO genes is unusual within the Solanaceae. Moreover, the phenotypes of the PFGLO1PFGLO2 double silencing mutants suggested that PFGLO2, through genetically interacting with PFGLO1, also exerts a role in the control of organ number and tip development of the second floral whorl. Our results, therefore, shed new light on the functional evolution of the duplicated GLO genes. PMID:24390390

  2. 80-W cw TEM{sub 00} IR beam generation by use of a laser-diode-side-pumped Nd:YAG rod laser

    Energy Technology Data Exchange (ETDEWEB)

    Konno, Susumu; Fujikawa, Shuichi; Yasui, Koji [Mitsubishi Electric Corp. Amagasaki, Hyogo (Japan). Advanced Technology R and D Center


    We have demonstrated high-efficient and high-power operation of a diode-side-pumped Nd:YAG rod laser. The laser has a simple and scalable configuration consisting of a diffusive pumping reflector and an advanced cavity configuration for polarization-dependent bifocusing compensation. (author)

  3. Development of Materials for a Military Overgarment for Protection Against CW Agents and Studies of New Fluorochemicals for Use as Finishes. (United States)


    and most solvents absorbency good wet and dry tensile and tear strengths :’ softness and good drape heat sealability ,4 Typical Masslinn papers...Toluene 50 :f the Good-rite Plasticizer GP 3 better ’ibr thoplex B-15 25 negligible kraft kraft LAe Solids add-on was determined by extraction of the...fair good fair good Ifwedie good good harsh soft a Treated to apply 25% Rhoplex B-15, 2% FC-2’- and 0. o5% Phobotex FTC siids on weight of paper

  4. An Ancient Duplication of Apple MYB Transcription Factors Is Responsible for Novel Red Fruit-Flesh Phenotypes1[C][W (United States)

    Chagné, David; Lin-Wang, Kui; Espley, Richard V.; Volz, Richard K.; How, Natalie M.; Rouse, Simon; Brendolise, Cyril; Carlisle, Charmaine M.; Kumar, Satish; De Silva, Nihal; Micheletti, Diego; McGhie, Tony; Crowhurst, Ross N.; Storey, Roy D.; Velasco, Riccardo; Hellens, Roger P.; Gardiner, Susan E.; Allan, Andrew C.


    Anthocyanin accumulation is coordinated in plants by a number of conserved transcription factors. In apple (Malus × domestica), an R2R3 MYB transcription factor has been shown to control fruit flesh and foliage anthocyanin pigmentation (MYB10) and fruit skin color (MYB1). However, the pattern of expression and allelic variation at these loci does not explain all anthocyanin-related apple phenotypes. One such example is an open-pollinated seedling of cv Sangrado that has green foliage and develops red flesh in the fruit cortex late in maturity. We used methods that combine plant breeding, molecular biology, and genomics to identify duplicated MYB transcription factors that could control this phenotype. We then demonstrated that the red-flesh cortex phenotype is associated with enhanced expression of MYB110a, a paralog of MYB10. Functional characterization of MYB110a showed that it was able to up-regulate anthocyanin biosynthesis in tobacco (Nicotiana tabacum). The chromosomal location of MYB110a is consistent with a whole-genome duplication event that occurred during the evolution of apple within the Maloideae family. Both MYB10 and MYB110a have conserved function in some cultivars, but they differ in their expression pattern and response to fruit maturity. PMID:23096157

  5. Additional Amphivasal Bundles in Pedicel Pith Exacerbate Central Fruit Dominance and Induce Self-Thinning of Lateral Fruitlets in Apple1[C][W (United States)

    Celton, Jean-Marc; Dheilly, Emmanuelle; Guillou, Marie-Charlotte; Simonneau, Fabienne; Juchaux, Marjorie; Costes, Evelyne; Laurens, François; Renou, Jean-Pierre


    Apple (Malus × domestica) trees naturally produce an excess of fruitlets that negatively affect the commercial value of fruits brought to maturity and impact their capacity to develop flower buds the following season. Therefore, chemical thinning has become an important cultural practice, allowing the selective removal of unwanted fruitlets. As the public pressure to limit the use of chemical agents increases, the control of thinning becomes a major issue. Here, we characterized the self-thinning capacity of an apple hybrid genotype from the tree scale to the molecular level. Additional amphivasal vascular bundles were identified in the pith of pedicels supporting the fruitlets with the lowest abscission potential (central fruitlet), indicating that these bundles might have a role in the acquisition of dominance over lateral fruitlets. Sugar content analysis revealed that central fruitlets were better supplied in sorbitol than lateral fruitlets. Transcriptomic profiles allowed us to identify genes potentially involved in the overproduction of vascular tissues in central pedicels. In addition, histological and transcriptomic data permitted a detailed characterization of abscission zone development and the identification of key genes involved in this process. Our data confirm the major role of ethylene, auxin, and cell wall-remodeling enzymes in abscission zone formation. The shedding process in this hybrid appears to be triggered by a naturally exacerbated dominance of central fruitlets over lateral ones, brought about by an increased supply of sugars, possibly through additional amphivasal vascular bundles. The characterization of this genotype opens new perspectives for the selection of elite apple cultivars. PMID:24550240

  6. AlGaAs-On-Insulator Nanowire with 750 nm FWM Bandwidth, -9 dB CW Conversion Efficiency, and Ultrafast Operation Enabling Record Tbaud Wavelength Conversion

    DEFF Research Database (Denmark)

    Pu, Minhao; Ottaviano, Luisa; Semenova, Elizaveta


    We present an AlGaAs-on-insulator platform for integrated nonlinear photonics. We demonstrate the highest reported conversion efficiency/length/pump-power, ultra-broadband fourwave mixing, and first-ever wavelength conversion of 1.28-Tbaud serial data signals in a 3-mm long dispersion-engineered AlGaAs...

  7. Frequency-Tracking CW Doppler Radar Solving Small-Angle Approximation and Null Point Issues in Non-Contact Vital Signs Monitoring. (United States)

    Mercuri, Marco; Liu, Yao-Hong; Lorato, Ilde; Torfs, Tom; Bourdoux, Andre; Van Hoof, Chris


    A Doppler radar operating as a Phase-Locked-Loop (PLL) in frequency demodulator configuration is presented and discussed. The proposed radar presents a unique architecture, using a single channel mixer, and allows to detect contactless vital signs parameters while solving the null point issue and without requiring the small angle approximation condition. Spectral analysis, simulations, and experimental results are presented and detailed to demonstrate the feasibility and the operational principle of the proposed radar architecture.

  8. Mechanism of CW Nd:YAG laser recanalization with modified fiber tips: influence of temperature and axial force on tissue penetration in vitro. (United States)

    Verdaasdonk, R M; Jansen, E D; Holstege, F C; Borst, C


    Modified fiber tips are used for laser angioplasty of totally occluded peripheral arteries. It has not been established, however, to what extent the mechanism of action of various laser probes is optical, thermal, or mechanical. We examined transparant contact probes (hemispherical contact probes and ball-shaped fibers) and metal laser probes, coupled to a continuous-wave Nd-YAG laser. By using homogeneous thick porcine fatty tissue samples submerged in blood plasma, tissue penetration was measured in relation to the temperature of the probe and the axial force exerted on the tissue. By using 15 W, 1 s laser pulses, the surface of transparent contact probes had to be first contaminated by carbonized tissue particles to achieve tissue penetration. Penetration increased from 1 to 10 mm per pulse when axial force increased from 20 to 100 g. Metal probes had to be sufficiently insulated from the liquid environment by water vapour entrapped in a denatured protein layer to exceed the threshold temperature of 225 degrees C for tissue penetration. When axial force increased from 20 to 80 g at 10 W continuous exposure, the velocity of tissue penetration increased in the range from 1 to 4 mm/s. Tissue penetration by modified fiber tips is attributed to both remodeling and vaporization of tissue. With transparent contact probes, tissue is heated partly by direct light absorption and partly by a hot probe surface. Axially directed force is necessary to displace lateral non-ablated tissue and to overcome mechanical resistance. We conclude that mechanical dilation due to axial catherization force (Dotter effect) contributes substantially to tissue penetration by transparent contact probes.

  9. CW-OSL measurement protocols using optical fibre Al2O3:C dosemeters

    DEFF Research Database (Denmark)

    Edmund, J.M.; Andersen, C.E.; Marckmann, C.J.


    A new system for in vivo dosimetry during radiotherapy has been introduced. Luminescence signals from a small crystal of carbon-doped aluminium oxide (Al2O3:C) are transmitted through an optical fibre cable to an instrument that contains optical filters, a photomultiplier tube and a green (532 nm...

  10. Compact, high-power, high-beam-quality quasi-CW microsecond five-pass zigzag slab 1319  nm amplifier. (United States)

    Guo, Chuan; Zuo, Junwei; Bian, Qi; Xu, Chang; Zong, Qinshuang; Bo, Yong; Shen, Yu; Zong, Nan; Gao, Hongwei; Lin, Yanyong; Yuan, Lei; Liu, Yang; Cui, Dafu; Peng, Qinjun; Xu, Zuyan


    We demonstrate a compact, high-power, quasi-continuous-wave (QCW) end-pumped 1319 nm Nd:YAG slab amplifier laser with good beam quality. The laser is based on a QCW pulse Nd:YAG master oscillator and Nd:YAG slab amplifier with multi-pass zigzag architecture. The amplifier operates at a pulse repetition frequency of 500 Hz and pulse width of ∼105  μs, delivering a maximum output power of 51.5 W under absorbed pump power of 217.8 W and corresponding to an extraction efficiency of 14.2%. The beam quality factor is measured to be Mx2=1.61 and My2=1.81 in the orthogonal directions. To the best of our knowledge, this is the first compact, high-power, high-beam-quality QCW Nd:YAG amplifier at 1319 nm based on a multi-pass zigzag slab structure.

  11. Highly Efficient, Compact, Wavelength Converters for Pulsed and CW Laser Sources Used in Lidar-Based Remote Sensing and Ranging Systems Project (United States)

    National Aeronautics and Space Administration — AdvR, Inc. proposes the development of a highly efficient, fiber pigtailed, waveguide-based UV frequency converter module. This UV module will be an important...

  12. Laticifer-Specific cis-Prenyltransferase Silencing Affects the Rubber, Triterpene, and Inulin Content of Taraxacum brevicorniculatum12[C][W (United States)

    Post, Janina; van Deenen, Nicole; Fricke, Julia; Kowalski, Natalie; Wurbs, David; Schaller, Hubert; Eisenreich, Wolfgang; Huber, Claudia; Twyman, Richard M.; Prüfer, Dirk; Gronover, Christian Schulze


    Certain Taraxacum species, such as Taraxacum koksaghyz and Taraxacum brevicorniculatum, produce large amounts of high-quality natural rubber in their latex, the milky cytoplasm of specialized cells known as laticifers. This high-molecular mass biopolymer consists mainly of poly(cis-1,4-isoprene) and is deposited in rubber particles by particle-bound enzymes that carry out the stereospecific condensation of isopentenyl diphosphate units. The polymer configuration suggests that the chain-elongating enzyme (rubber transferase; EC is a cis-prenyltransferase (CPT). Here, we present a comprehensive analysis of transgenic T. brevicorniculatum plants in which the expression of three recently isolated CPTs known to be associated with rubber particles (TbCPT1 to -3) was heavily depleted by laticifer-specific RNA interference (RNAi). Analysis of the CPT-RNAi plants by nuclear magnetic resonance, size-exclusion chromatography, and gas chromatography-mass spectrometry indicated a significant reduction in rubber biosynthesis and a corresponding 50% increase in the levels of triterpenes and the main storage carbohydrate, inulin. Transmission electron microscopy revealed that the laticifers in CPT-RNAi plants contained fewer and smaller rubber particles than wild-type laticifers. We also observed lower activity of hydroxymethylglutaryl-coenzyme A reductase, the key enzyme in the mevalonate pathway, reflecting homeostatic control of the isopentenyl diphosphate pool. To our knowledge, this is the first in planta demonstration of latex-specific CPT activity in rubber biosynthesis. PMID:22238421

  13. Hydrogen Sulfide Generated by l-Cysteine Desulfhydrase Acts Upstream of Nitric Oxide to Modulate Abscisic Acid-Dependent Stomatal Closure1[C][W (United States)

    Scuffi, Denise; Álvarez, Consolación; Laspina, Natalia; Gotor, Cecilia; Lamattina, Lorenzo; García-Mata, Carlos


    Abscisic acid (ABA) is a well-studied regulator of stomatal movement. Hydrogen sulfide (H2S), a small signaling gas molecule involved in key physiological processes in mammals, has been recently reported as a new component of the ABA signaling network in stomatal guard cells. In Arabidopsis (Arabidopsis thaliana), H2S is enzymatically produced in the cytosol through the activity of l-cysteine desulfhydrase (DES1). In this work, we used DES1 knockout Arabidopsis mutant plants (des1) to study the participation of DES1 in the cross talk between H2S and nitric oxide (NO) in the ABA-dependent signaling network in guard cells. The results show that ABA did not close the stomata in isolated epidermal strips of des1 mutants, an effect that was restored by the application of exogenous H2S. Quantitative reverse transcription polymerase chain reaction analysis demonstrated that ABA induces DES1 expression in guard cell-enriched RNA extracts from wild-type Arabidopsis plants. Furthermore, stomata from isolated epidermal strips of Arabidopsis ABA receptor mutant pyrabactin-resistant1 (pyr1)/pyrabactin-like1 (pyl1)/pyl2/pyl4 close in response to exogenous H2S, suggesting that this gasotransmitter is acting downstream, although acting independently of the ABA receptor cannot be ruled out with this data. However, the Arabidopsis clade-A PROTEIN PHOSPHATASE2C mutant abscisic acid-insensitive1 (abi1-1) does not close the stomata when epidermal strips were treated with H2S, suggesting that H2S required a functional ABI1. Further studies to unravel the cross talk between H2S and NO indicate that (1) H2S promotes NO production, (2) DES1 is required for ABA-dependent NO production, and (3) NO is downstream of H2S in ABA-induced stomatal closure. Altogether, data indicate that DES1 is a unique component of ABA signaling in guard cells. PMID:25266633

  14. Rapid Ammonia Gas Transport Accounts for Futile Transmembrane Cycling under NH3/NH4+ Toxicity in Plant Roots1[C][W (United States)

    Coskun, Devrim; Britto, Dev T.; Li, Mingyuan; Becker, Alexander; Kronzucker, Herbert J.


    Futile transmembrane NH3/NH4+ cycling in plant root cells, characterized by extremely rapid fluxes and high efflux to influx ratios, has been successfully linked to NH3/NH4+ toxicity. Surprisingly, the fundamental question of which species of the conjugate pair (NH3 or NH4+) participates in such fluxes is unresolved. Using flux analyses with the short-lived radioisotope 13N and electrophysiological, respiratory, and histochemical measurements, we show that futile cycling in roots of barley (Hordeum vulgare) seedlings is predominately of the gaseous NH3 species, rather than the NH4+ ion. Influx of 13NH3/13NH4+, which exceeded 200 µmol g–1 h–1, was not commensurate with membrane depolarization or increases in root respiration, suggesting electroneutral NH3 transport. Influx followed Michaelis-Menten kinetics for NH3 (but not NH4+), as a function of external concentration (Km = 152 µm, Vmax = 205 µmol g–1 h–1). Efflux of 13NH3/13NH4+ responded with a nearly identical Km. Pharmacological characterization of influx and efflux suggests mediation by aquaporins. Our study fundamentally revises the futile-cycling model by demonstrating that NH3 is the major permeating species across both plasmalemma and tonoplast of root cells under toxicity conditions. PMID:24134887

  15. Transient Transcriptional Regulation of the CYS-C1 Gene and Cyanide Accumulation upon Pathogen Infection in the Plant Immune Response1[C][W (United States)

    García, Irene; Rosas, Tábata; Bejarano, Eduardo R.; Gotor, Cecilia; Romero, Luis C.


    Cyanide is produced concomitantly with ethylene biosynthesis. Arabidopsis (Arabidopsis thaliana) detoxifies cyanide primarily through the enzyme β-cyanoalanine synthase, mainly by the mitochondrial CYS-C1. CYS-C1 loss of function is not toxic for the plant and leads to an increased level of cyanide in cys-c1 mutants as well as a root hairless phenotype. The classification of genes differentially expressed in cys-c1 and wild-type plants reveals that the high endogenous cyanide content of the cys-c1 mutant is correlated with the biotic stress response. Cyanide accumulation and CYS-C1 gene expression are negatively correlated during compatible and incompatible plant-bacteria interactions. In addition, cys-c1 plants present an increased susceptibility to the necrotrophic fungus Botrytis cinerea and an increased tolerance to the biotrophic Pseudomonas syringae pv tomato DC3000 bacterium and Beet curly top virus. The cys-c1 mutation produces a reduction in respiration rate in leaves, an accumulation of reactive oxygen species, and an induction of the alternative oxidase AOX1a and pathogenesis-related PR1 expression. We hypothesize that cyanide, which is transiently accumulated during avirulent bacterial infection and constitutively accumulated in the cys-c1 mutant, uncouples the respiratory electron chain dependent on the cytochrome c oxidase, and this uncoupling induces the alternative oxidase activity and the accumulation of reactive oxygen species, which act by stimulating the salicylic acid-dependent signaling pathway of the plant immune system. PMID:23784464

  16. Evolutionary Conserved Function of Barley and Arabidopsis 3-KETOACYL-CoA SYNTHASES in Providing Wax Signals for Germination of Powdery Mildew Fungi1[C][W (United States)

    Weidenbach, Denise; Jansen, Marcus; Franke, Rochus B.; Hensel, Goetz; Weissgerber, Wiebke; Ulferts, Sylvia; Jansen, Irina; Schreiber, Lukas; Korzun, Viktor; Pontzen, Rolf; Kumlehn, Jochen; Pillen, Klaus; Schaffrath, Ulrich


    For plant pathogenic fungi, such as powdery mildews, that survive only on a limited number of host plant species, it is a matter of vital importance that their spores sense that they landed on the right spot to initiate germination as quickly as possible. We investigated a barley (Hordeum vulgare) mutant with reduced epicuticular leaf waxes on which spores of adapted and nonadapted powdery mildew fungi showed reduced germination. The barley gene responsible for the mutant wax phenotype was cloned in a forward genetic screen and identified to encode a 3-KETOACYL-CoA SYNTHASE (HvKCS6), a protein participating in fatty acid elongation and required for synthesis of epicuticular waxes. Gas chromatography-mass spectrometry analysis revealed that the mutant has significantly fewer aliphatic wax constituents with a chain length above C-24. Complementation of the mutant restored wild-type wax and overcame germination penalty, indicating that wax constituents less present on the mutant are a crucial clue for spore germination. Investigation of Arabidopsis (Arabidopsis thaliana) transgenic plants with sense silencing of Arabidopsis REQUIRED FOR CUTICULAR WAX PRODUCTION1, the HvKCS6 ortholog, revealed the same germination phenotype against adapted and nonadapted powdery mildew fungi. Our findings hint to an evolutionary conserved mechanism for sensing of plant surfaces among distantly related powdery mildews that is based on KCS6-derived wax components. Perception of such a signal must have been evolved before the monocot-dicot split took place approximately 150 million years ago. PMID:25201879

  17. Bacteria-Triggered Systemic Immunity in Barley Is Associated with WRKY and ETHYLENE RESPONSIVE FACTORs But Not with Salicylic Acid1[C][W (United States)

    Dey, Sanjukta; Wenig, Marion; Langen, Gregor; Sharma, Sapna; Kugler, Karl G.; Knappe, Claudia; Hause, Bettina; Bichlmeier, Marlies; Babaeizad, Valiollah; Imani, Jafargholi; Janzik, Ingar; Stempfl, Thomas; Hückelhoven, Ralph; Kogel, Karl-Heinz; Mayer, Klaus F.X.


    Leaf-to-leaf systemic immune signaling known as systemic acquired resistance is poorly understood in monocotyledonous plants. Here, we characterize systemic immunity in barley (Hordeum vulgare) triggered after primary leaf infection with either Pseudomonas syringae pathovar japonica (Psj) or Xanthomonas translucens pathovar cerealis (Xtc). Both pathogens induced resistance in systemic, uninfected leaves against a subsequent challenge infection with Xtc. In contrast to systemic acquired resistance in Arabidopsis (Arabidopsis thaliana), systemic immunity in barley was not associated with NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 or the local or systemic accumulation of salicylic acid. Instead, we documented a moderate local but not systemic induction of abscisic acid after infection of leaves with Psj. In contrast to salicylic acid or its functional analog benzothiadiazole, local applications of the jasmonic acid methyl ester or abscisic acid triggered systemic immunity to Xtc. RNA sequencing analysis of local and systemic transcript accumulation revealed unique gene expression changes in response to both Psj and Xtc and a clear separation of local from systemic responses. The systemic response appeared relatively modest, and quantitative reverse transcription-polymerase chain reaction associated systemic immunity with the local and systemic induction of two WRKY and two ETHYLENE RESPONSIVE FACTOR (ERF)-like transcription factors. Systemic immunity against Xtc was further associated with transcriptional changes after a secondary/systemic Xtc challenge infection; these changes were dependent on the primary treatment. Taken together, bacteria-induced systemic immunity in barley may be mediated in part by WRKY and ERF-like transcription factors, possibly facilitating transcriptional reprogramming to potentiate immunity. PMID:25332505

  18. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: The mechanism of the drilling of holes in vertical metallic plates by cw CO2 laser radiation (United States)

    Likhanskii, V. V.; Loboiko, A. I.; Antonova, G. F.; Krasyukov, A. G.; Sayapin, V. P.


    The possibility of making a hole in a vertical plate with the aid of laser radiation at a surface temperature not exceeding the boiling point is analysed neglecting the vapour pressure. The mechanism of the degradation of the liquid layer involving a reduction of its thickness, as a result of the redistribution of the molten mass owing to the operation of the force of gravity and of thermocapillary convection, is examined. The theoretical dependence of the critical size of the molten zone on the plate thickness is obtained and a comparison is made with experimental data.

  19. Highly Efficient, Compact, Wavelength Converters for Pulsed and CW Laser Sources Used in Lidar-Based Remote Sensing and Ranging Systems Project (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will demonstrate the feasibility of fabricating waveguides in stoichiometric lithium tantalite (SLT) for...

  20. A PIP1 Aquaporin Contributes to Hydrostatic Pressure-Induced Water Transport in Both the Root and Rosette of Arabidopsis1[C][W (United States)

    Postaire, Olivier; Tournaire-Roux, Colette; Grondin, Alexandre; Boursiac, Yann; Morillon, Raphaël; Schäffner, Anton R.; Maurel, Christophe


    Aquaporins are channel proteins that facilitate the transport of water across plant cell membranes. In this work, we used a combination of pharmacological and reverse genetic approaches to investigate the overall significance of aquaporins for tissue water conductivity in Arabidopsis (Arabidopsis thaliana). We addressed the function in roots and leaves of AtPIP1;2, one of the most abundantly expressed isoforms of the plasma membrane intrinsic protein family. At variance with the water transport phenotype previously described in AtPIP2;2 knockout mutants, disruption of AtPIP1;2 reduced by 20% to 30% the root hydrostatic hydraulic conductivity but did not modify osmotic root water transport. These results document qualitatively distinct functions of different PIP isoforms in root water uptake. The hydraulic conductivity of excised rosettes (Kros) was measured by a novel pressure chamber technique. Exposure of Arabidopsis plants to darkness increased Kros by up to 90%. Mercury and azide, two aquaporin inhibitors with distinct modes of action, were able to induce similar inhibition of Kros by approximately 13% and approximately 25% in rosettes from plants grown in the light or under prolonged (11–18 h) darkness, respectively. Prolonged darkness enhanced the transcript abundance of several PIP genes, including AtPIP1;2. Mutant analysis showed that, under prolonged darkness conditions, AtPIP1;2 can contribute to up to approximately 20% of Kros and to the osmotic water permeability of isolated mesophyll protoplasts. Therefore, AtPIP1;2 can account for a significant portion of aquaporin-mediated leaf water transport. The overall work shows that AtPIP1;2 represents a key component of whole-plant hydraulics. PMID:20034965

  1. Conserved and Divergent Rhythms of Crassulacean Acid Metabolism-Related and Core Clock Gene Expression in the Cactus Opuntia ficus-indica1[C][W (United States)

    Mallona, Izaskun; Egea-Cortines, Marcos; Weiss, Julia


    The cactus Opuntia ficus-indica is a constitutive Crassulacean acid metabolism (CAM) species. Current knowledge of CAM metabolism suggests that the enzyme phosphoenolpyruvate carboxylase kinase (PPCK) is circadian regulated at the transcriptional level, whereas phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), NADP-malic enzyme (NADP-ME), and pyruvate phosphate dikinase (PPDK) are posttranslationally controlled. As little transcriptomic data are available from obligate CAM plants, we created an expressed sequence tag database derived from different organs and developmental stages. Sequences were assembled, compared with sequences in the National Center for Biotechnology Information nonredundant database for identification of putative orthologs, and mapped using Kyoto Encyclopedia of Genes and Genomes Orthology and Gene Ontology. We identified genes involved in circadian regulation and CAM metabolism for transcriptomic analysis in plants grown in long days. We identified stable reference genes for quantitative polymerase chain reaction and found that OfiSAND, like its counterpart in Arabidopsis (Arabidopsis thaliana), and OfiTUB are generally appropriate standards for use in the quantification of gene expression in O. ficus-indica. Three kinds of expression profiles were found: transcripts of OfiPPCK oscillated with a 24-h periodicity; transcripts of the light-active OfiNADP-ME and OfiPPDK genes adapted to 12-h cycles, while transcript accumulation patterns of OfiPEPC and OfiMDH were arrhythmic. Expression of the circadian clock gene OfiTOC1, similar to Arabidopsis, oscillated with a 24-h periodicity, peaking at night. Expression of OfiCCA1 and OfiPRR9, unlike in Arabidopsis, adapted best to a 12-h rhythm, suggesting that circadian clock gene interactions differ from those of Arabidopsis. Our results indicate that the evolution of CAM metabolism could be the result of modified circadian regulation at both the transcriptional and posttranscriptional levels. PMID:21677095

  2. A Pair of Tabersonine 16-Hydroxylases Initiates the Synthesis of Vindoline in an Organ-Dependent Manner in Catharanthus roseus1[C][W (United States)

    Besseau, Sébastien; Kellner, Franziska; Lanoue, Arnaud; Thamm, Antje M.K.; Salim, Vonny; Schneider, Bernd; Geu-Flores, Fernando; Höfer, René; Guirimand, Grégory; Guihur, Anthony; Oudin, Audrey; Glevarec, Gaëlle; Foureau, Emilien; Papon, Nicolas; Clastre, Marc; Giglioli-Guivarc’h, Nathalie; St-Pierre, Benoit; Werck-Reichhart, Danièle; Burlat, Vincent; De Luca, Vincenzo; O’Connor, Sarah E.; Courdavault, Vincent


    Hydroxylation of tabersonine at the C-16 position, catalyzed by tabersonine 16-hydroxylase (T16H), initiates the synthesis of vindoline that constitutes the main alkaloid accumulated in leaves of Catharanthus roseus. Over the last decade, this reaction has been associated with CYP71D12 cloned from undifferentiated C. roseus cells. In this study, we isolated a second cytochrome P450 (CYP71D351) displaying T16H activity. Biochemical characterization demonstrated that CYP71D12 and CYP71D351 both exhibit high affinity for tabersonine and narrow substrate specificity, making of T16H, to our knowledge, the first alkaloid biosynthetic enzyme displaying two isoforms encoded by distinct genes characterized to date in C. roseus. However, both genes dramatically diverge in transcript distribution in planta. While CYP71D12 (T16H1) expression is restricted to flowers and undifferentiated cells, the CYP71D351 (T16H2) expression profile is similar to the other vindoline biosynthetic genes reaching a maximum in young leaves. Moreover, transcript localization by carborundum abrasion and RNA in situ hybridization demonstrated that CYP71D351 messenger RNAs are specifically located to leaf epidermis, which also hosts the next step of vindoline biosynthesis. Comparison of high- and low-vindoline-accumulating C. roseus cultivars also highlights the direct correlation between CYP71D351 transcript and vindoline levels. In addition, CYP71D351 down-regulation mediated by virus-induced gene silencing reduces vindoline accumulation in leaves and redirects the biosynthetic flux toward the production of unmodified alkaloids at the C-16 position. All these data demonstrate that tabersonine 16-hydroxylation is orchestrated in an organ-dependent manner by two genes including CYP71D351, which encodes the specific T16H isoform acting in the foliar vindoline biosynthesis. PMID:24108213

  3. Broad-Spectrum Suppression of Innate Immunity Is Required for Colonization of Arabidopsis Roots by the Fungus Piriformospora indica1[C][W (United States)

    Jacobs, Sophie; Zechmann, Bernd; Molitor, Alexandra; Trujillo, Marco; Petutschnig, Elena; Lipka, Volker; Kogel, Karl-Heinz; Schäfer, Patrick


    Piriformospora indica is a root-colonizing basidiomycete that confers a wide range of beneficial traits to its host. The fungus shows a biotrophic growth phase in Arabidopsis (Arabidopsis thaliana) roots followed by a cell death-associated colonization phase, a colonization strategy that, to our knowledge, has not yet been reported for this plant. P. indica has evolved an extraordinary capacity for plant root colonization. Its broad host spectrum encompasses gymnosperms and monocotyledonous as well as dicotyledonous angiosperms, which suggests that it has an effective mechanism(s) for bypassing or suppressing host immunity. The results of our work argue that P. indica is confronted with a functional root immune system. Moreover, the fungus does not evade detection but rather suppresses immunity triggered by various microbe-associated molecular patterns. This ability to suppress host immunity is compromised in the jasmonate mutants jasmonate insensitive1-1 and jasmonate resistant1-1. A quintuple-DELLA mutant displaying constitutive gibberellin (GA) responses and the GA biosynthesis mutant ga1-6 (for GA requiring 1) showed higher and lower degrees of colonization, respectively, in the cell death-associated stage, suggesting that P. indica recruits GA signaling to help establish proapoptotic root cell colonization. Our study demonstrates that mutualists, like pathogens, are confronted with an effective innate immune system in roots and that colonization success essentially depends on the evolution of strategies for immunosuppression. PMID:21474434

  4. Cytokinin Antagonizes Abscisic Acid-Mediated Inhibition of Cotyledon Greening by Promoting the Degradation of ABSCISIC ACID INSENSITIVE5 Protein in Arabidopsis1[C][W (United States)

    Guan, Chunmei; Wang, Xingchun; Feng, Jian; Hong, Sulei; Liang, Yan; Ren, Bo; Zuo, Jianru


    In higher plants, seed germination is followed by postgerminative growth. One of the key developmental events during postgerminative growth is cotyledon greening, which enables a seedling to establish photosynthetic capacity. The plant phytohormone abscisic acid (ABA) plays a vital role by inhibiting seed germination and postgerminative growth in response to dynamically changing internal and environmental cues. It has been shown that ABSCISIC ACID INSENSITIVE5 (ABI5), a basic leucine zipper transcription factor, is an important factor in the regulation of the ABA-mediated inhibitory effect on seed germination and postgerminative growth. Conversely, the phytohormone cytokinin has been proposed to promote seed germination by antagonizing the ABA-mediated inhibitory effect. However, the underpinning molecular mechanism of cytokinin-repressed ABA signaling is largely unknown. Here, we show that cytokinin specifically antagonizes ABA-mediated inhibition of cotyledon greening with minimal effects on seed germination in Arabidopsis (Arabidopsis thaliana). We found that the cytokinin-antagonized ABA effect is dependent on a functional cytokinin signaling pathway, mainly involved in the cytokinin receptor gene CYTOKININ RESPONSE1/ARABIDOPSIS HISTIDINE KINASE4, downstream histidine phosphotransfer protein genes AHP2, AHP3, and AHP5, and a type B response regulator gene, ARR12, which genetically acts upstream of ABI5 to regulate cotyledon greening. Cytokinin has no apparent effect on the transcription of ABI5. However, cytokinin efficiently promotes the proteasomal degradation of ABI5 in a cytokinin signaling-dependent manner. These results define a genetic pathway through which cytokinin specifically induces the degradation of ABI5 protein, thereby antagonizing ABA-mediated inhibition of postgerminative growth. PMID:24443524

  5. Observation of dust particles ejected from the tungsten surface by transient heat flux with small-angle scattering of cw laser light

    Directory of Open Access Journals (Sweden)

    L.N. Vyacheslavov


    Full Text Available A new test facility for experimental simulation of transient heat load expected in the ITER divertor during unmitigated events is developed. Application of a long-pulse (0.1–0.3ms wide-aperture (up to 2cm2 electron beam as a heating device provides powerful energy loads at a tungsten target with FHF> 250MJm−2s−0.5. Dynamics of tungsten particles in the ablation plume is investigated with a novel for PSI experiments small-angle laser light scattering technique. The threshold of intense droplet generation and dynamics of particles sizes are estimated.

  6. Mrt, a Gene Unique to Fungi, Encodes an Oligosaccharide Transporter and Facilitates Rhizosphere Competency in Metarhizium robertsii1[C][W (United States)

    Fang, Weiguo; St. Leger, Raymond J.


    The symbiotic associations between rhizospheric fungi and plants have enormous environmental impact. Fungi are crucial to plant health as antagonists of pathogens and herbivores and facilitate the uptake of soil nutrients. However, little is known about the plant products obtained by fungi in exchange or how they are transported through the symbiotic interface. Here, we demonstrate that sucrose and raffinose family oligosaccharides in root exudates are important for rhizosphere competence in the insect pathogen Metarhizium robertsii (formerly known as Metarhizium anisopliae). We identified mutants in the Metarhizium raffinose transporter (Mrt) gene of M. robertsii that grew poorly in root exudate and were greatly reduced in rhizosphere competence on grass roots. Studies on sugar uptake, including competition assays, revealed that MRT was a sucrose and galactoside transporter. Disrupting MRT resulted in greatly reduced or no growth on sucrose and galactosides but did not affect growth on monosaccharides or oligosaccharides composed entirely of glucose subunits. Consistent with this, expression of Mrt is exclusively up-regulated by galactosides and sucrose. Expressing a green fluorescent protein gene under the control of the Mrt promoter confirmed that MRT was expressed by germlings in the vicinity of grass roots but not in surrounding bulk soil. Disrupting Mrt did not reduce virulence to insects, demonstrating that Mrt is exclusively involved in M. robertsii’s interactions with plants. To our knowledge, MRT is the first oligosaccharide transporter identified and characterized in a fungus and is unique to filamentous fungi, but homologous genes in Magnaporthe, Ustilago, Aspergillus, Fusarium, Epichloe, and Penicillium species indicate that oligosaccharide transport is of widespread significance. PMID:20837701

  7. 100 mW of blue light at 405 nm from intracavity doubling of CW Ti:Sapphire laser utilising BiBO-crystal

    DEFF Research Database (Denmark)

    Thorhauge, Morten; Mortensen, Jesper Liltorp; Tidemand-Lichtenberg, Peter


    100 mW of coherent blue light with a wavelength of 405 nm was generated utilising a BiB3O6 (BiBO) nonlinear crystal to frequency double a Ti:Sapphire laser. Phase match curves as well as sensitivity to angular misalignment was calculated. The BiBO crystal was found to be excellent...... for this application. Temperature dependance was uncritical for this crystal, while power stability was good. The pump-to-blue optical conversion efficiency was approximately 2%. Unfortunately catastrophic coating damage was observed...

  8. The GUINEVERE Project for Accelerator Driven System Physics


    Billebaud, A.; Baeten, P.; Aït Abderrahim, H.; Ban, G.; Baylac, M.; Bergmans, G.; Bondoux, D.; Bouvier, J.; Chabod, S.; De Conto, J.M.; Dessagne, P.; Gaudiot, G; Gautier, J. M.; Granget, G.; Heitz, G


    paper 9414; International audience; The GUINEVERE project is part of the EUROTRANS Integrated Project of the 6th EURATOM Framework Programme. It is mainly devoted to ADS on-line reactivity monitoring validation, sub-criticality determination and operational procedures (loading, start-up, shut-down, ...) as a follow-up of the MUSE experiments. The project consists in coupling a fast lead core, set-up in the VENUS reactor at SCK*CEN Mol (B), with a GENEPI neutron source under construction by CN...

  9. Particle accelerators and nuclear energy: the challenge of reliability; Acceleradores de particulas y energia nuclear: el desafio de la fiabilidad

    Energy Technology Data Exchange (ETDEWEB)

    Brucker, R.; Fernandez Ramos, P.


    High energy particle accelerators, that used to serve a purpose only in fundamental research, will soon be used in industrial applications of nuclear energy. In this context, they will be submitted to unprecedented (as far as such machines are concerned) reliability requirements. In order to meet them, reliability studies need to be carried out. This article describes the experience gained by Empresarios Agrupados in that field (with the Eurotrans and Ifmif projects) and presents their future activities in the framework of the Myrrha project, that is aimed at building the first ADS reactor in the world. (Author)

  10. AcEST: BP912185 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 2 OS=Myxococ... 33 9.0 >tr|Q1CW29|Q1CW29_MYXXD CRISPR-associated protein Crm2 OS=Myxococcus xanthus (strain DK 1622) GN=crm...9 Definition tr|Q1CW29|Q1CW29_MYXXD CRISPR-associated protein Crm2 OS=Myxococcus ...g significant alignments: (bits) Value tr|Q1CW29|Q1CW29_MYXXD CRISPR-associated protein Crm

  11. The GUINEVERE project at the VENUS facility

    Energy Technology Data Exchange (ETDEWEB)

    Baeten, P.; Ait Abderrahim, H.; Bergmans, G.; Heyse, J.; Maes, D.; Verboomen, B.; Vermeersch, F.; Vittiglio, G. [SCK.CEN, Boeretang 200, 2400 Mol (Belgium); Aoust, T.; Baylac, M.; Billebaud, A.; Bondoux, D.; Bouvier, J.; De Conto, J.M.; Grondin, D.; Marchand, D.; Micoud, R.; Planet, M. [LPSC-CNRS-IN2P3/UJF/INPG, 53 Avenue des Martyrs. 38026 Grenoble cedex (France); Ban, G.; Gautier, J.M.; Lecolley, F.R.; Lecouey, J.L.; Marie, N.; Merrer, Y.; Steckmeyer, J.C. [LPC Caen, ENSICAEN/Universite de Caen/ CNRS-IN2P3, Caen (France); Dessagne, P.; Gaudiot, G.; Heitz, G.; Kerveno, M.; Ruescas, C. [IPHC-DRS/ULP/CNRS-IN2P3, Strasbourg (France); Laune, B.; Reynet, D. [IPNO, CNRS-IN2P3/UPS, Orsay (France); Granget, G.; Mellier, F.; Rimpault, G. [CEA-Cadarache, 13108 Saint Paul lez Durance (France)


    The GUINEVERE project is an international project in the framework of IP-EUROTRANS, the FP6 program which aims at addressing the main issues for ADS development in the framework of partitioning and transmutation for nuclear waste volume and radiotoxicity reduction. The GUINEVERE project is carried out in the context of domain 2 of IP-EUROTRANS, ECATS, devoted to specific experiments for the coupling of an accelerator, a target and a subcritical core. These experiments should provide an answer to the questions of online reactivity monitoring, sub-criticality determination and operational procedures (loading, start-up, shutdown,...) in an ADS by 2009-2010. The project has the objective to couple a fast lead core, within the VENUS building operated by the SCK.CEN, with a neutron generator able to work in three different modes: pulsed, continuous and continuous with beam interruptions at the millisecond scale. In order to achieve this goal, the VENUS facility has to be adapted and a modified GENEPI-3C accelerator has to be designed and constructed. The paper describes the main modifications to the reactor core and facility and to the accelerator, which will be executed during the years 2008 and 2009, and the experimental programme which will start in 2009. (authors)

  12. Linac design for intense hadron beams

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chuan


    Based on the RFQ and H-type DTL structures, this dissertation is dedicated to study the beam dynamics in the presence of significantly strong space-charge effects while accelerating intense hadron beams in the low- and medium-{beta} region. Besides the 5 mA/30 mA, 17 MeV proton injector (RFQ+DTL) and the 125 mA, 40 MeV deuteron DTL of the EUROTRANS and IFMIF facilities, a 200 mA, 700 keV proton RFQ has been also intensively studied for a small-scale but ultra-intense neutron source FRANZ planned at Frankfurt University. The most remarkable properties of the FRANZ RFQ and the IFMIF DTL are the design beam intensities, 200 mA and 125 mA. A new design approach, which can provide a balanced and accelerated beam bunching at low energy, has been developed for intense beams. To design the IFMIF DTL and the injector DTL part of the EUROTRANS driver linac, which have been foreseen as the first real applications of the novel superconducting CH-DTL structure, intensive attempts have been made to fulfill the design goals under the new conditions. For the IFMIF DTL, the preliminary IAP design has been considerably improved with respect to the linac layout as well as the beam dynamics. By reserving sufficient drift spaces for the cryosystem, diagnostic devices, tuner and steerer, introducing SC solenoid lenses and adjusting the accelerating gradients and accordingly other configurations of the cavities, a more realistic, reliable and efficient linac system has been designed. On the other hand, the specifications and positions of the transverse focusing elements as well as the phase- and energy-differences between the bunch-center particle and the synchronous particle at the beginning of the {phi}{sub s}=0 sections have been totally redesigned. For the EUROTRANS injector DTL, in addition to the above-mentioned procedures, extra optimization concepts to coordinate the beam dynamics between two intensities have been applied. In the beam transport simulations for both DTL designs

  13. Removal of nutrients from septic tank effluent with baffle subsurface-flow constructed wetlands (United States)

    Lihu Cui; Ying Ouyang; Weizhi Yang; Zhujian Huang; Qiaoling Xu; Guangwei Yu


    Three new baffle flow constructed wetlands (CWs), namely the baffle horizontal flow CW (Z1), baffle vertical flow CW (Z2) and baffle hybrid flow CW (Z3), along with one traditional horizontal subsurface flow CW (Z4) were designed to test the removal efficiency of nitrogen (N) and phosphorus (P) from the septic tank effluent under varying hydraulic retention times (HRTs...

  14. Research on an FM/cw ladar system using a 64 × 64 InGaAs metal-semiconductor-metal self-mixing focal plane array of detectors. (United States)

    Gao, Jian; Sun, Jianfeng; Cong, Mingyu


    Frequency-modulated/continuous-wave imaging systems are a focal plane array (FPA) ladar architecture that is applicable to smart munitions, reconnaissance, face recognition, robotic navigation, etc. In this paper, we report a 64×64 pixel FPA ladar system we built using a 1550 nm amplified laser diode transmitter and an InAlAs/InGaAs metal-semiconductor-metal self-mixing detector array and the test results attained over the years it was constructed. Finally, we gained 4D imaging (3D range + 1D intensity) of the target with the range of 220 m.

  15. The Ma Gene for Complete-Spectrum Resistance to Meloidogyne Species in Prunus Is a TNL with a Huge Repeated C-Terminal Post-LRR Region1[C][W (United States)

    Claverie, Michel; Dirlewanger, Elisabeth; Bosselut, Nathalie; Van Ghelder, Cyril; Voisin, Roger; Kleinhentz, Marc; Lafargue, Bernard; Abad, Pierre; Rosso, Marie-Noëlle; Chalhoub, Boulos; Esmenjaud, Daniel


    Root-knot nematode (RKN) Meloidogyne species are major polyphagous pests of most crops worldwide, and cultivars with durable resistance are urgently needed because of nematicide bans. The Ma gene from the Myrobalan plum (Prunus cerasifera) confers complete-spectrum, heat-stable, and high-level resistance to RKN, which is remarkable in comparison with the Mi-1 gene from tomato (Solanum lycopersicum), the sole RKN resistance gene cloned. We report here the positional cloning and the functional validation of the Ma locus present at the heterozygous state in the P.2175 accession. High-resolution mapping totaling over 3,000 segregants reduced the Ma locus interval to a 32-kb cluster of three Toll/Interleukin1 Receptor-Nucleotide Binding Site-Leucine-Rich Repeat (LRR) genes (TNL1–TNL3), including a pseudogene (TNL2) and a truncated gene (TNL3). The sole complete gene in this interval (TNL1) was validated as Ma, as it conferred the same complete-spectrum and high-level resistance (as in P.2175) using its genomic sequence and native promoter region in Agrobacterium rhizogenes-transformed hairy roots and composite plants. The full-length cDNA (2,048 amino acids) of Ma is the longest of all Resistance genes cloned to date. Its TNL structure is completed by a huge post-LRR (PL) sequence (1,088 amino acids) comprising five repeated carboxyl-terminal PL exons with two conserved motifs. The amino-terminal region (213 amino acids) of the LRR exon is conserved between alleles and contrasts with the high interallelic polymorphisms of its distal region (111 amino acids) and of PL domains. The Ma gene highlights the importance of these uncharacterized PL domains, which may be involved in pathogen recognition through the decoy hypothesis or in nuclear signaling. PMID:21482634

  16. Non-Invasive Assessment of Left Ventricular End-Diastolic Pressure in Patients with Chronic Aortic Regurgitation, Comparison of the Sensitivity and Specificity of CW Doppler Echocardiography with Angiography

    Directory of Open Access Journals (Sweden)

    M Esmaeilzadeh


    Full Text Available Background: Left ventricular end diastolic pressure could be estimated collectively using various measures of mitral valve and pulmonary venous flow velocities. In patients with aortic regurgitation, the AR velocity reflects the diastolic pressure difference between the aorta and the left ventricle. We sought to predict the left ventricular end diastolic pressure by a new Doppler index as aortic regurgitation peak early to late diastolic pressure gradient ratio.Patients and Methods: Fifty three patients with at least moderate aortic regurgitation were enrolled in this study. Physical examination, electrocardiography and echocardiography were performed one day before cardiac catheterization. The severity of AR was graded according to the recommendations of American society for echocardiography. The pressure half time, aortic regurgitation early diastolic velocity , aortic regurgitation early diastolic pressure gradient , aortic regurgitation end diastolic velocity, aortic regurgitation end diastolic pressure gradient, and early diastolic to end diastolic pressure gradient ratio of averaged three beats were measured and recorded. The results from cardiac catheterization and echocardiography were compared.Result: The early diastolic to end diastolic pressure gradient ratio was very accurate (80% for determining the left ventricular end diastolic pressure (P =0.01. An early diastolic to end diastolic pressure gradient ratio of 1.5 has a sensitivity of 96% and a specificity of 32% for left ventricular end diastolic pressure ≤12 mmHg. The best cutoff value of early diastolic to end diastolic pressure gradient ratio for the prediction of left ventricular end diastolic pressure >12 mmHg was higher than 2.0, with a sensitivity of 71% and specificity of 96% We found no significant correlation between the left ventricular end diastolic pressure with either left ventricular ejection fraction or aortic regurgitation severity in cardiac catheterization (P =0.5.Conclusion: Doppler echocardiography is a viable alternative of cardiac catheterization for determination of the left ventricular end diastolic pressure. The early diastolic to end diastolic pressure gradient ratio is a simple, easy and new method for assessment of the LVEDP in patients with severe chronic aortic regurgitation.

  17. High-power actively Q-switched single-mode 1342 nm Nd:YVO4 ring laser, injection-locked by a cw single-frequency microchip laser. (United States)

    Koch, Peter; Bartschke, Juergen; L'huillier, Johannes A


    In this paper we report on the realization of a single-mode Q-switched Nd:YVO4 ring laser at 1342 nm. Unidirectional and single-mode operation of the ring laser is achieved by injection-locking with a continuous wave Nd:YVO4 microchip laser, emitting a single-frequency power of up to 40 mW. The ring laser provides a single-mode power of 13.9 W at 10 kHz pulse repetition frequency with a pulse duration of 18.2 ns and an excellent beam quality (M2 laser, a power of 8.7 W at 671 nm with a pulse duration of 14.8 ns and a beam propagation factor of M2 < 1.1 is obtained. The 671 nm radiation features a long-term spectral width of 75 MHz.

  18. Generation of 6.8 W of CW output power at 1550 nm using small mode field diameter Er:Yb co-doped double clad fiber in laser oscillator configuration (United States)

    Gurram, Srikanth; Kuruvilla, A.; Singh, Rajpal; Bindra, K. S.


    We report studies on erbium:ytterbium doped fiber laser, that uses a commercially available off-the-shelf Er:Yb co-doped single mode fiber with small mode field diameter of 7 µm, which is compatible with single mode fibers used in most of the communication systems. In a FBG based laser oscillator configuration pumped at 976 nm, the single transverse mode fiber laser emitted more than 6.87 Watts of output power at 1550 nm with a conversion efficiency of ~32% over a narrow line width. The pump radiation is coupled into active fiber using free-space optics. To the best of our knowledge, this is the highest power reported in the 1.55 µm region by using commercially available off-the-shelf active fiber of small mode field diameter (~7 µm) in a simple laser oscillator configuration with 9×× nm pumping. We also observed the effect of weak secondary grating structure in FBGs on the spectral characteristics of EYDFLs and explained its significance for co-doped fiber lasers such as erbium-ytterbium fiber lasers.

  19. Multiband space time processing for torpedo alert sonar (United States)

    Chen, Yang; Zhao, Anbang


    A space time processing technology using harmonic CW wave is introduced to enhance the detecting performance of motion target based on active towed sonar based on CW wave. The detecting ability of CW wave and harmonic CW wave in multi-path channel is analyzed comparatively. The simulation results indicate that in multi-path channel harmonic CW wave is provided with a better performance.

  20. The feasibility of using complex wastewater from a monosodium glutamate factory to cultivate Spirulina subsalsa and accumulate biochemical composition. (United States)

    Jiang, Liqun; Pei, Haiyan; Hu, Wenrong; Ji, Yan; Han, Lin; Ma, Guixia


    This paper is mainly observations on the growth and biomass accumulation of Spirulina subsalsa in modified Zarrouk medium supplemented with complex wastewater (CW, from a monosodium glutamate factory) in different concentrations. High ammonia in 75% and 100% CW inhibits algae growth, but maximum biomass production (2.86mgL(-1)) was obtained in 25% CW (concentration of CW in medium was 25%). Different CW concentration promoted biomass composition accumulation at different degrees, 41% of protein content in 25% CW and 18% of carbohydrate in 50% CW. In terms of economy, a concentration of 25% CW was suitable for protein production and 50% for lipid and carbohydrate production. These results suggested that CW is a feasible replacement in part for cultivation of S. subsalsa to economize input of water and nutrients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Influences of plant type on bacterial and archaeal communities in constructed wetland treating polluted river water. (United States)

    Long, Yan; Yi, Hao; Chen, Sili; Zhang, Zhengke; Cui, Kai; Bing, Yongxin; Zhuo, Qiongfang; Li, Bingxin; Xie, Shuguang; Guo, Qingwei


    Both bacteria and archaeal communities can play important roles in biogeochemical processes in constructed wetland (CW) system. However, the influence of plant type on microbial community in surface water CW remains unclear. The present study investigated bacterial and archaeal communities in five surface water CW systems with different plant species. The abundance, richness, and diversity of both bacterial and archaeal communities considerably differed in these five CW systems. Compared with the other three CW systems, the CW systems planted with Vetiveria zizanioides or Juncus effusus L. showed much higher bacterial abundance but lower archaeal abundance. Bacteria outnumbered archaea in each CW system. Moreover, the CW systems planted with V. zizanioides or J. effusus L. had relatively lower archaeal but higher bacterial richness and diversity. In each CW system, bacterial community displayed much higher richness and diversity than archaeal community. In addition, a remarkable difference of both bacterial and archaeal community structures was observed in the five studied CW systems. Proteobacteria was the most abundant bacterial group (accounting for 33-60 %). Thaumarchaeota organisms (57 %) predominated in archaeal communities in CW systems planted with V. zizanioides or J. effusus L., while Woesearchaeota (23 or 24 %) and Euryarchaeota (23 or 15 %) were the major archaeal groups in CW systems planted with Cyperus papyrus or Canna indica L. Archaeal community in CW planted with Typha orientalis Presl was mainly composed of unclassified archaea. Therefore, plant type exerted a considerable influence on microbial community in surface water CW system.

  2. Mesures de taux de production d'éléments gazeux et volatiles lors de réactions induites par des protons de 1 et 1,4 GeV sur des cibles épaisses de plomb-bismuth liquides

    CERN Document Server

    Tall, Yoro


    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6th Euratom Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target which one molten lead-bismuth concept is studied by the SUBATECH (physique SUBAtomique et des TECHnologies associées) laboratory in Nantes. The irradiation of molten lead-bismuth target with energetic proton beam generates volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-b...

  3. Measurement of the fission cross-section of $^{240}$Pu and $^{242}$Pu at CERN's n_TOF Facility

    CERN Multimedia

    Pavlik, A F; Gonzalez romero, E M

    The n_TOF Collaboration proposes to continue the fission program, already started in 2002-2004, taking advantage of the newly constructed Work Sector Type A, with the measurement of the two isotopes : $^{240}$ Pu and $^{242}$ Pu. They are both of major importance for reactor physics applications and are included in the Nuclear Energy Agency (NEA) High Priority List [1], in the NEA WPEC Subgroup 26 Report on the accuracy of nuclear data for advanced reactor designe [2] and in the EU 6$^{th}$ Framework Programme IP-EUROTRANS/NUDATRA reports [3]. Based on those requests, the measurement of the fission cross-section of the two Pu isotopes is one of the objectives of the project ANDES of the FP7 EURATOM program [4].

  4. A randomised controlled trial of the resistive heating blanket versus the convective warming system for preventing hypothermia during major abdominal surgery. (United States)

    Tanaka, Noriyoshi; Ohno, Yuko; Hori, Megumi; Utada, Mai; Ito, Kenji; Suzuki, Toshiyasu


    We compared resistive heating (RH) and upper-body convective warming (CW) in 70 patients (RH 33, CW 31, 6 excluded) undergoing major abdominal surgery. The effect of RH was not inferior to that of CW for the time-weighted average core temperature, and the lower limit of 95% CW was greater than -0.5 degrees C. Resistive heating showed no inferiority in maintaining core temperature compared with convective warming.

  5. A complementary bioinformatics approach to identify potential plant cell wall glycosytransferase encoding genes

    DEFF Research Database (Denmark)

    Egelund, Jack; Skjøt, Michael; Geshi, Naomi


    . Although much is known with regard to composition and fine structures of the plant CW, only a handful of CW biosynthetic GT genes-all classified in the CAZy system-have been characterized. In an effort to identify CW GTs that have not yet been classified in the CAZy database, a simple bioinformatics...

  6. Three pectin methylesterase inhibitors protect cell wall integrity for arabidopsis immunity to Botrytis

    DEFF Research Database (Denmark)

    Lionetti, Vincenzo; Fabri, Eleonora; Caroli, Monica De


    Infection by necrotrophs is a complex process that starts with the breakdown of the cell wall (CW) matrix initiated by CW-degrading enzymes and results in an extensive tissue maceration. Plants exploit induced defense mechanisms based on biochemical modification of the CW components to protect...

  7. Wastewater polishing by a channelized macrophyte-dominated wetland and anaerobic digestion of the harvested phytomass (United States)

    : Constructed wetlands (CW) offer a mechanism to meet regulatory standards for wastewater treatment while minimizing energy inputs. To optimize CW wastewater polishing activities and investigate integration of CW with energy production from anaerobic digestion we constructed a pair of three-tier ch...

  8. Determination of the effectiveness of two methods for usability evaluation using a CPOE medication ordering system

    NARCIS (Netherlands)

    Khajouei, R.; Hasman, A.; Jaspers, M. W. M.


    Objectives: To assess the effectiveness of two usability evaluation methods, cognitive walkthrough (CW) and think aloud (TA), for identifying usability problems and to compare the performance of CW and TA in identifying different types of usability problems. Methods: A CW was performed by two

  9. A comparison of charcoal- and slag-based constructed wetlands for ...

    African Journals Online (AJOL)

    Subsurface-flow constructed wetlands (CW) with charcoal- or slag-based bed matrices were investigated for their potential use in remediating acid mine drainage (AMD). A CW is effectively a reactor in which some components of the wastewater are broken down by the organisms occurring within the CW, whilst others may ...

  10. Literacy skills in primary school-aged children with pragmatic language impairment: a comparison with children with specific language impairment. (United States)

    Freed, Jenny; Adams, Catherine; Lockton, Elaine


    Children with pragmatic language impairment (CwPLI) are characterized by difficulties with the interpersonal use of language in social contexts and they possess a range of language difficulties that affect their educational attainment. Since literacy skills are central to this attainment, one way of identifying appropriate support needs for CwPLI would be to profile their reading and writing skills as a group. To investigate the word reading, non-word reading, reading comprehension, and written expression skills of CwPLI and a comparison group of children with specific language impairment (CwSLI). CwSLI were recruited in order to examine any overlaps in literacy impairments for the two groups. Primary school-aged CwPLI (n= 59) and CwSLI (n= 12) were recruited from speech and language therapists. Children completed standardized assessments of literacy skills. The level of impairment for each component literacy skill was examined for CwPLI and CwSLI. For the CwPLI, group mean scores on each of the literacy skills were at the lower end of the normal range compared with population norms. The range of individual scores was large, with some children scoring near floor level and others scoring up to 2 SDs (standard deviations) above the mean, illustrating the heterogeneity of literacy skills within the group. For the CwSLI, group mean scores on each of the literacy skills were between 1 SD and 2 SDs below the population mean. CwSLI were significantly more impaired on all of the literacy measures compared with CwPLI. This difference remained even when receptive language ability and non-verbal intelligence were controlled for. The results demonstrate that there is a high level of literacy impairment within CwPLI and CwSLI, providing evidence that individualized literacy skill intervention is important for the long-term academic outcome of these children. © 2010 Royal College of Speech & Language Therapists.

  11. Distinguishing familiarity from fluency for the compound word pair effect in associative recognition. (United States)

    Ahmad, Fahad N; Hockley, William E


    We examined whether processing fluency contributes to associative recognition of unitized pre-experimental associations. In Experiments 1A and 1B, we minimized perceptual fluency by presenting each word of pairs on separate screens at both study and test, yet the compound word (CW) effect (i.e., hit and false-alarm rates greater for CW pairs with no difference in discrimination) did not reduce. In Experiments 2A and 2B, conceptual fluency was examined by comparing transparent (e.g., hand bag) and opaque (e.g., rag time) CW pairs in lexical decision and associative recognition tasks. Lexical decision was faster for transparent CWs (Experiment 2A) but in associative recognition, the CW effect did not differ by CW pair type (Experiment 2B). In Experiments 3A and 3B, we examined whether priming that increases processing fluency would influence the CW effect. In Experiment 3A, CW and non-compound word pairs were preceded with matched and mismatched primes at test in an associative recognition task. In Experiment 3B, only transparent and opaque CW pairs were presented. Results showed that presenting matched versus mismatched primes at test did not influence the CW effect. The CW effect in yes-no associative recognition is due to reliance on enhanced familiarity of unitized CW pairs.

  12. Simultaneous removal of nitrate and sulfate from greenhouse wastewater by constructed wetlands. (United States)

    Gruyer, Nicolas; Dorais, Martine; Alsanius, Beatrix W; Zagury, Gérald J


    This study evaluated the effectiveness of C-enriched subsurface-flow constructed wetlands in reducing high concentrations of nitrate (NO) and sulfate (SO) in greenhouse wastewaters. Constructed wetlands were filled with pozzolana, planted with common cattail (), and supplemented as follows: (i) constructed wetland with sucrose (CW+S), wetland units with 2 g L of sucrose solution from week 1 to 28; (ii) constructed wetland with compost (CW+C), wetland units supplemented with a reactive mixture of compost and sawdust; (iii) constructed wetland with compost and no sucrose (CW+CNS) from week 1 to 18, and constructed wetland with compost and sucrose (CW+CS) at 2 g L from week 19 to 28; and (iv) constructed wetland (CW). During 28 wk, the wetlands received a typical reconstituted greenhouse wastewater containing 500 mg L SO and 300 mg L NO. In CW+S, CW+C, and CW+CS, appropriate C:N ratio (7:3.4) and redox potential (-53 to 39 mV) for denitrification resulted in 95 to 99% NO removal. Carbon source was not a limiting factor for denitrification in C-enriched constructed wetlands. In CW+S and CW+CS, the dissolved organic carbon (DOC)/SO ratios of 0.36 and 0.28 resulted in high sulfate-reducing bacteria (SRB) counts and high SO removal (98%), whereas low activities were observed at DOC/SO ratios of 0.02 (CW) to 0.11 (CW+C, CW+CNS). On week 19, when organic C content was increased by sucrose addition in CW+CS, SRB counts increased from 2.80 to 5.11 log[CFU+1] mL, resulting in a level similar to the one measured in CW+S (4.69 log[CFU+1] mL). Consequently, high sulfate reduction occurred after denitrification, suggesting that low DOC (38-54 mg L) was the limiting factor. In CW, DOC concentration (9-10 mg L) was too low to sustain efficient denitrification and, therefore, sulfate reduction. Furthermore, the high concentration of dissolved sulfides observed in CW+S and CW+CS treated waters were eliminated by adding FeCl. Copyright © by the American Society of Agronomy, Crop

  13. Ultrastructure of the innermost surface of differentiating normal and compression wood tracheids as revealed by field emission scanning electron microscopy. (United States)

    Kim, Jong Sik; Awano, Tatsuya; Yoshinaga, Arata; Takabe, Keiji


    The ultrastructure of the innermost surface of Cryptomeria japonica differentiating normal wood (NW) and compression wood (CW) was comparatively investigated by field emission electron microscopy (FE-SEM) combined with enzymatic degradation of hemicelluloses. Cellulose microfibril (CMF) bundles were readily observed in NW tracheids in the early stage of secondary cell wall formation, but not in CW tracheids because of the heavy accumulation of amorphous materials composed mainly of galactans and lignin. This result suggests that the ultrastructural deposition of cell wall components in the tracheid cell wall differ between NW and CW from the early stage of secondary cell wall formation. Delignified NW and CW tracheids showed similar structural changes during differentiating stages after xylanase or β-mannanase treatment, whereas they exhibited clear differences in ultrastructure in mature stages. Although thin CMF bundles were exposed in both delignified mature NW and CW tracheids by xylanase treatment, ultrastructural changes following β-mannanase treatment were only observed in CW tracheids. CW tracheids also showed different degradation patterns between xylanase and β-mannanase. CMF bundles showed a smooth surface in delignified mature CW tracheids treated with xylanase, whereas they had an uneven surface in delignified mature CW tracheids treated with β-mannanase, indicating that the uneven surface of CMF bundles was related to xylans. The present results suggest that ultrastructural deposition and organization of lignin and hemicelluloses in CW tracheids may differ from those of NW tracheids.

  14. Power Generation Enhancement by Utilizing Plant Photosynthate in Microbial Fuel Cell Coupled Constructed Wetland System

    Directory of Open Access Journals (Sweden)

    Shentan Liu


    Full Text Available In the present study, a new technology that coupled constructed wetland (CW with microbial fuel cell (MFC (CW-MFC was developed to convert solar energy into electricity on the principles of photosynthetic MFC by utilizing root exudates of Ipomoea aquatica as part of fuel. The maximum power density of 12.42 mW m−2 produced from the CW-MFC planted with Ipomoea aquatica was 142% higher than that of 5.13 mW m−2 obtained from the unplanted CW-MFC. The maximum power output for the planted CW-MFC could be divided into two parts: the maximum power yield from in the water body was 66.05 KJ Kg−1  , and the maximum power transformation from plant photosynthesis was 2.31 GJ ha−1 year−1. The average COD removal efficiencies were 92.1% and 94.8% in the unplanted CW-MFC and planted CW-MFC, respectively; the average TN removal efficiencies amounted to 54.4% and 90.8% in the unplanted CW-MFC and planted CW-MFC. This research demonstrates that planting Ipomoea aquatica in the CW-MFC achieved a higher power density and nutrient removal of nitrogen simultaneously.

  15. Hydrodynamic modelling of free water-surface constructed storm water wetlands using a finite volume technique. (United States)

    Zounemat-Kermani, Mohammad; Scholz, Miklas; Tondar, Mohammad-Mahdi


    One of the key factors in designing free water-surface constructed wetlands (FWS CW) is the hydraulic efficiency (λ), which depends primarily on the retention time of the polluted storm water. Increasing the hydraulic retention time (HRT) at various flow levels will increase λ of the overall constructed wetland (CW). The effects of characteristic geometric features that increase HRT were explored through the use of a two-dimensional depth-average hydrodynamic model. This numerical model was developed to solve the equations of continuity and motions on an unstructured triangular mesh using the Galerkin finite volume formulation and equations of the k-ε turbulence model. Eighty-nine diverse forms of artificial FWS CW with 11 different aspect ratios were numerically simulated and subsequently analysed for four scenarios: rectangular CW, modified rectangular CW with rounded edges, different inlet/outlet configurations of CW, and surface and submerged obstructions in front of the inlet part of the CW. Results from the simulations showed that increasing the aspect ratio has a direct influence on the enhancement of λ in all cases. However, the aspect ratio should be at least 9 in order to achieve an appropriate rate for λ in rectangular CW. Modified rounded rectangular CW improved λ by up to 23%, which allowed for the selection of a reduced aspect ratio. Simulation results showed that CW with low aspect ratios benefited from obstructions and optimized inlet/outlet configurations in terms of improved HRT.

  16. Nutrient and organic matter removal from low strength sewage treated with constructed wetlands. (United States)

    Mello, D; Carvalho, K Q; Passig, F H; Freire, F B; Borges, A C; Lima, M X; Marcelino, G R


    The role of Eichhornia crassipes for removing pollutants from low strength sewage was evaluated in three pilot-scale constructed wetlands (CW): CW 1, planted with E. crassipes in a filter media; CW 2, unplanted, composed by filter media; and CW 3, composed by E. crassipes floating on the sewage. The operation was divided into three stages by varying the nominal hydraulic retention time into: (I) 24 h; (II) 48 h; (III) 72 h. Temporal sampling profiles were carried out with collection of the influent and effluent samples to determine temperature, pH, chemical oxygen demand (COD), TKN and TP. Contents of TP and TN were analyzed in the plant tissue of the macrophyte. The best removal efficiency rates for phosphorus (38%) and TKN (47%) were obtained in CW 3 for 72 h. The highest COD removal was observed in the CW 2 (80%) for 48 h. The macrophyte E. crassipes contributed to the absorption process with uptake rate percentages of 8.3% (CW 1) and 9.0% (CW 3) for TN and 0.78% (CW 1) and 1.56% (CW 3) for TP on the dry matter of the plant. The chosen species planted in the systems contributed to the achievement of higher nutrient removal.

  17. Relative growth in the fiddler crab Uca uruguayensis Nobili, 1901 (Brachyura, Ocypodidae from Garças River mangrove, Guaratuba Bay, southern Brazil

    Directory of Open Access Journals (Sweden)

    Salise Brandt Martins

    Full Text Available A study on the relative growth was carried out in a population of the fiddler crab Uca uruguayensis from the mangrove of Garças River, Guaratuba Bay, Paraná State, southern Brazil. The dimensions analyzed were the length of the major chela (LMC of males and width of the abdomen (AW of females, because they are related to reproductive activities of waving (males and egg incubation (females. The cheliped handedness in males was also analyzed. The LMC was measured in 480 males, the AW in 566 females, and all crabs had the carapace width (CW measured that was considered as the reference dimension for both sexes. The inflection point in the graphs between each the dimensions and CW was calculated with the aid of the software REGRANS. The CW ranged from 2.33 to 8.33 mm in males and from 1.65 to 7.79 mm in females. The relationship between CW and LMC showed an inflection point at 4.14 mm CW among males, and between CW and AW at 3.52 mm CW among females. The allometric growth was positive for both dimensions throughout the entire ontogeny of both sexes, before and after the puberty. The equations describing the relationship between CW and LMC in males were: logLMC = - 0.695960 + 1.72.logCW for juveniles and logLMC = - 1.212513 + 2.5.logCW for adults. In females, the equations were logAW = - 0.519071 + 1.02.logCW and logAW = - 0.902874 + 1.73.logCW, respectively for juveniles and adults. The population of U. uruguayensis from Guaratuba Bay is composed of the smallest crabs, and it also attains morphological sexual maturity at smallest CW. The frequency of occurrence of right and left handed males was statistically the same (1:1 as in most population of fiddler crabs.

  18. The human element in Russia`s chemical weapons disposal efforts

    Energy Technology Data Exchange (ETDEWEB)

    Khripunov, I. [Univ. of Georgia, Athens, GA (United States)


    There has been ample room for global concern about the speed with which the Russian Federation has been moving to destroy the enormous stockpile of Soviet-built chemical warfare (CW) agents since the termination of CS production in 1987. The use of CW by terrorists in Japan in 1995 brought new focus on the need to eliminate the CW stockpiles. Coincidence or not, the Russian government took a major public step toward dismantling CW weapons just four days after the Tokyo terrorist attack. The author examines the reasons for the delays in Russian CW decommissioning effort and the failure to consider the human element in dealing with local communities where CW weapons are to be destroyed.

  19. Web-mediated interspecific competition among spider mites. (United States)

    Morimoto, K; Furuichi, H; Yano, S; Osakabe, M


    Some spider mites, such as Tetranychus spp. and Amphitetranychus spp., create complicated webs (CWs), whereas others, such as Panonychus spp., produce little webs (LWs). We verified whether interspecific competition occurred between CW and LW mites via habitat arrangement under laboratory conditions. The complicated webs produced by CW mites clearly inhibited juvenile development in LW mites, whereas there was no effect of LW mites on CW mites. In oviposition site choice tests, both CW and LW females preferred the lower surface of leaves to the upper surface. The preference of LW mites for the lower leaf surface, even in the presence of CW mite webs, suggests that the costs of amensalism are outweighed by the possible benefits, such as avoiding rain. These findings show that the shift in mite species composition from LW to CW mites can occur as a consequence of the interspecific association between spider mites via their webs, without pesticide applications or the presence of natural enemies.

  20. NCBI nr-aa BLAST: CBRC-DMEL-08-0064 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available b|AAB59125.1| 13.8 kd ORF [Plasmid ColE1] gb|ABI93156.1| hypothetical protein [Cloning vector pOri1] gb|ABI9...3161.1| hypothetical protein [Cloning vector pCW] gb|ABI93166.1| hypothetical protein [Cloning vector pCW1]|ABI93171.1| hypothetical protein [Cloning vector pCW2] NP_040360.1 9e-63 95% ...

  1. Comparative study of the biochemical changes and volatile compound formations during the production of novel whey-based kefir beverages and traditional milk kefir


    Magalhães, Karina Teixeira; Dragone,Giuliano; Pereira, Gilberto V. de Melo; Oliveira, J. M.; Domingues, Lucília; J. A. Teixeira; Silva, João B. Almeida e; Schwan, Rosane F.


    Cheese whey (CW) and deproteinised cheese whey (DCW) were investigated for their suitability as novel substrates for the production of kefir-like beverages. Lactose consumption, ethanol production, as well as organic acids and volatile compounds formation, were determined during CW and DCW fermentation by kefir grains and compared with values obtained during the production of traditional milk kefir. The results showed that kefir grains were able to utilise lactose from CW and DCW and produce ...

  2. Basewide Groundwater Operable Unit. Groundwater Operable Unit Remedial Investigation/Feasibility Study Report. Volume 3 (United States)


    348000 2179540 75 410 ARC 43 Edison 348990 2167650 49 45 385 390 ARC 44 Highlands Teeame 368440 2181660 110 577 575 ARC 45 Swamn Estates Gas 340550...CW- 12 W 35xC-165W0AC3 SCW-12 ALVA &43 0 .CW- 127 AC7x.K 4;W9 WNW 2 -144 ARC-43 x *ARC-24 *W- -59-122 . ARC-23 ARC- 13 a ARC-A O( ARC_41%AR-1 CW-1 ra

  3. Storm event-scale nutrient attenuation in constructed wetlands experiencing a Mediterranean climate: A comparison of a surface flow and hybrid surface-subsurface flow system. (United States)

    Adyel, Tanveer M; Oldham, Carolyn E; Hipsey, Matthew R


    Among different Water Sensitive Urban Design options, constructed wetlands (CWs) are used to protect and restore downstream water quality by attenuating nutrients generated by stormwater runoff. This research compared the nutrient attenuation ability during a diverse population of storm events of two CWs: (a) a hybrid CW with multiple alternating surface flow (SF) and laterite-based subsurface flow (SSF) compartments, and (b) a single stage SF CW. Within-storm variability, nutrient concentrations were assessed at 2 to 3-h intervals at both the main inlet and outlet of each CW. Dissolved oxygen concentrations of the surface waters were also monitored at 10-min intervals using high frequency in situ sensors. Nutrient loads into the CWs were observed to be higher when a high rainfall event occurred, particularly after longer antecedent dry conditions. Longer hydraulic retention times promoted higher attenuation at both sites. However, the relative extent of nutrient attenuation differed between the CW types; the mean total nitrogen (TN) attenuation in the hybrid and SF CW was 45 and 48%, respectively. The hybrid CW attenuated 67% total phosphorus (TP) loads on average, while the SF CW acted as a net TP source. Periodic storm events transitioned the lentic CW into a lotic CW and caused riparian zone saturation; it was therefore hypothesized that such saturation of organic matter rich-riparian zones led to release of TP in the system. The hybrid CW attenuated the released TP in the downstream laterite-based SSF compartments. Diel oxygen metabolism calculated before and after the storm events was found to be strongly correlated with water temperature, solar exposure and antecedent dry condition during the pre-storm conditions. Furthermore, the SF CW showed a significant relationship between overall nutrient load attenuation and the change in oxygen metabolism during the storm perturbation, suggesting oxygen variation could be a useful proxy indicator of CW function

  4. Farm and factory production of goat cheese whey results in distinct chemical composition. (United States)

    Moreno-Indias, I; Castro, N; Morales-delaNuez, A; Sánchez-Macías, D; Assunção, P; Capote, J; Argüello, A


    To analyze differences in fat and protein content in cheese whey (CW) manufactured in cheese-making factories and farms, goat CW samples were obtained from 60 cheese-making farms and 20 cheese factories. Gross composition of samples was analyzed by using an MIRIS device (MIRIS Inc., Uppsala, Sweden), whey protein composition was subjected to electrophoretic analysis, and fatty acid composition was analyzed via gas chromatography. Goat CW from farms contained higher dry matter content (70.6 vs. 50.8 g/L, farms vs. cheese factories, respectively) and a higher fat percentage (10.5 vs. 1.2% over dry matter, farms vs. cheese factories, respectively) than CW from cheese factories. Analysis of individual proteins showed that CW from farms contained higher concentrations of lactoferrin (0.4 vs. 0.2 mg/mL of CW, farms vs. cheese factories, respectively) and caprine serum albumin (0.6 vs. 0.4 mg/mL of whey, farms vs. cheese factories, respectively) than CW from cheese factories. No differences were observed in the fatty acid profile. The main fatty acids present in goat CW were C16:0, C18:1, C14:0, and C18:0. Thus, the origin of CW affects gross composition and the protein profile, but not the fatty acid profile.

  5. Utilization of Waste Clay from Boron Production in Bituminous Geosynthetic Barrier (GBR-B) Production as Landfill Liner


    Müfide Banar; Yücel Güney; Aysun Özkan; Zerrin Günkaya; Eren Bayrakcı; Derya Ulutaş


    Bituminous geomembranes, one type of geosynthetics, include a hot bituminous mixture with mineral filler and reinforcement. In this study, boron production waste clay (CW) was used as filler to produce a geosynthetic barrier with bentonite, waste tire, and bitumen. Bentonite and waste tires were used as auxiliary fillers and bitumen as the binder. CW/bitumen, CW/bentonite/bitumen, and CW/waste tire/bitumen mixtures were prepared by using a laboratory mixer at 100°C. Hot mixtures were extruded...

  6. Geometrical and Graphical Solutions of Quadratic Equations. (United States)

    Hornsby, E. John, Jr.


    Presented are several geometrical and graphical methods of solving quadratic equations. Discussed are Greek origins, Carlyle's method, von Staudt's method, fixed graph methods and imaginary solutions. (CW)

  7. Bandwidth-adaptable silicon photonic differentiator employing a slow light effect

    DEFF Research Database (Denmark)

    Yan, Siqi; Cheng, Ziwei; Frandsen, Lars Hagedorn


    exploits the slow light effect in a photonic crystal waveguide (PhCW) to overcome the inherent bandwidth limitation of current photonic DIFFs. We fabricated a PhCW Mach-Zehnder interferometer (PhCW-MZI) on the silicon-onisolator material platform to validate our concept. Input Gaussian pulses with full...... width to half-maximums (FWHMs) ranging from 2.7 to 81.4 ps are accurately differentiated using our PhCW-MZI. Our all-passive scheme circumvents the bandwidth bottlenecks of previously reported photonic DIFFs and can greatly broaden the application area of photonic DIFFs. (C) 2017 Optical Society...

  8. Broadband Fiber Raman Power-Amplifier for Narrow Linewidth Tunable Seed Lasers Used in Spectroscopic Sensing Project (United States)

    National Aeronautics and Space Administration — We propose an energy and space efficient high power continuous wave (cw) narrow linewidth broadband fiber Raman amplifier (FRA) with spectrally tunable...

  9. Carbon nanotube coatings as chemical absorbers (United States)

    Tillotson, Thomas M.; Andresen, Brian D.; Alcaraz, Armando


    Airborne or aqueous organic compound collection using carbon nanotubes. Exposure of carbon nanotube-coated disks to controlled atmospheres of chemical warefare (CW)-related compounds provide superior extraction and retention efficiencies compared to commercially available airborne organic compound collectors. For example, the carbon nanotube-coated collectors were four (4) times more efficient toward concentrating dimethylmethyl-phosphonate (DMMP), a CW surrogate, than Carboxen, the optimized carbonized polymer for CW-related vapor collections. In addition to DMMP, the carbon nanotube-coated material possesses high collection efficiencies for the CW-related compounds diisopropylaminoethanol (DIEA), and diisopropylmethylphosphonate (DIMP).

  10. Fractional analysis of arsenic in subsurface-flow constructed wetlands with different length to depth ratios. (United States)

    Singhakant, C; Koottatep, T; Satayavivad, J


    Arsenic (As) removal in subsurface-flow constructed wetlands (CW) planting with vetiver grasses was experimented by comparing between two different configurations; (i) deep-bed units (dpCW) with length to depth (L:D) ratio=2 and (ii) shallow-bed units (shCW) with L:D ratio=8; operating at hydraulic retention time (HRT) of 6, 9, and 12 days. The tracer study of CW units revealed that no effect of L:D ratio on dispersion number could be determined, but affecting to the effective volume ratio. Based on the data obtained from the pilot-scale experiments of CW units for 117 days, it is apparent that the dpCW could achieve relatively high As removals (52.9%, 59.2%, and 72.1% at HRT of 6, 9, and 12 days, respectively). Analysis of As mass balance showed that only 0.2-0.4% of As input was uptaken by vetiver grasses whereas the major portion was retained in the CW media (38.9-77.6%). Forms of the retained As was determined by sequential fractionation which could indicate As complexation with iron and manganese on the media surface of 31-38% and As trapping into the media of 42-52% of the total. No obvious difference of As fractions in bed of between dpCW and shCW units was observable.

  11. Measurements of gas and volatile element production rates from an irradiated molten lead and lead-bismuth spallation target with proton beams of 1 and 1.4 GeV; Mesures de taux de production d'elements gazeux et volatiles lors de reactions induites par des protons de 1 et 1,4 GeV sur des cibles epaisses de plomb et plomb-bismuth liquides

    Energy Technology Data Exchange (ETDEWEB)

    Tall, Y


    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6. EURATOM Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target. SUBATECH (physique Sub-Atomique et des Technologies associees) laboratory is involved to the study of the chosen liquid lead-bismuth as a spallation ADS target. The irradiation of liquid lead-bismuth target with energetic proton beam generates in addition to neutrons, volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-bismuth target, the experiment IS419 was performed at the ISOLDE facility at CERN (Centre Europeen de la Recherche Nucleaire). This experiment constitutes the frame of the thesis whose main objective is to assess and study the production and release rates of many gas and volatile element from the irradiated lead-bismuth target with an energetic proton beam. The obtained data are compared to Monte Carlo simulation code (MCNPX) results in order to test the intranuclear cascade model of Bertini and of Cugnon, and the evaporation options of Dresner and Schmidt. (author)

  12. System and safety studies of accelerator driven transmutation Annual Report 2005

    Energy Technology Data Exchange (ETDEWEB)

    Gudowski, Waclaw; Wallenius, Jan; Arzhanov, Vasily; Jolkkonen, Mikael; Eriksson, Marcus; Seltborg, Per; Westlen, Daniel; Lagerstedt, Christina; Isaksson, Patrick; Persson, Carl-Magnus; Aalander, Alexandra [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Nuclear and Reactor Physics


    The results of the research activities on System and Safety of Accelerator-Driven Transmutation (ADS) at the Department of Nuclear and Reactor Physics are described in this report followed by the Appendices of the relevant scientific papers published in 2005. PhD and Licentiate dissertations of Marcus Ericsson, Per Seltborg, Christina Lagerstedt and Daniel Westlen (see Appendices) reflect the research mainstream of 2005. Year 2005 was also very rich in international activities with ADS in focus. Summary of conferences, seminars and lecturing activities is given in Chapter 9 Research activities of 2005 have been focused on several areas: system and safety studies of ADS; subcritical experiments; ADS source efficiency studies; nuclear fuel cycle analysis; potential of reactor based transmutation; ADS fuel development; simulation of radiation damage; and development of codes and methods. Large part of the research activities has been well integrated with the European projects of the 5th and 6th Framework Programmes of the European Commission in which KTH is actively participating. In particular European projects: RED-IMPACT, CONFIRM, FUTURE, EUROTRANS and NURESIM.

  13. Decay Heat Removal and Transient Analysis in Accidental Conditions in the EFIT Reactor

    Directory of Open Access Journals (Sweden)

    Giacomino Bandini


    Full Text Available The development of a conceptual design of an industrial-scale transmutation facility (EFIT of several 100 MW thermal power based on accelerator-driven system (ADS is addressed in the frame of the European EUROTRANS Integral Project. In normal operation, the core power of EFIT reactor is removed through steam generators by four secondary loops fed by water. A safety-related decay heat removal (DHR system provided with four independent inherently safe loops is installed in the primary vessel to remove the decay heat by natural convection circulation under accidental conditions which are caused by a loss-of-heat sink (LOHS. In order to confirm the adequacy of the adopted solution for decay heat removal in accidental conditions, some multi-D analyses have been carried out with the SIMMER-III code. The results of the SIMMER-III code have been then used to support the RELAP5 1D representation of the natural circulation flow paths in the reactor vessel. Finally, the thermal-hydraulic RELAP5 code has been employed for the analysis of LOHS accidental scenarios.

  14. Nuclear Data for Safe Operation and Waste Transmutation: ANDES (Accurate Nuclear Data for nuclear Energy Sustainability); Datos nucleares para la operacion segura y la transmutacion de residuos: Andes (Datos Nucleares Precisos para la Sostenibilidad de la Energia Nuclear)

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, E. M.


    Nuclear research within the 7th Framework Program (FP7 and FP7+2) of EURATOM has devoted a significant fraction of its efforts to the development of advanced nuclear fuel cycles and reactor concepts, mainly fast reactors, aiming to improve the long term sustainability by reduction of the final wastes, optimal use of natural resources and improvement of safety in the present and future nuclear installations. The new design need more accurate basic nuclear data for isotopes, like minor actinides, potentially playing an important role in the operation, fuel concept, safety or final wastes of those reactors and fuel cycles. Four projects, ANDES, ERINDA, EUFRAT and CHANDA, supported by EURATOM within the FP7 and FP7+2, have put together most of the European Nuclear Data community to respond efficiently and in a coordinated way to those needs. This paper summarizes the objectives, and main achievements of ANDES, the project responsible for most of the measurements and technical achievements that was coordinated by CIEMAT. Indeed, CIEMAT has coordinated the nuclear data R and D projects within EURATOM during the last 7 years (NUDATRA domain of EUROTRANS, and ANDES) and will continue this coordination in the CHANDA project till 2017. (Author)

  15. Irradiation of structural materials in contact with lead bismuth eutectic in the high flux reactor

    Energy Technology Data Exchange (ETDEWEB)

    Magielsen, A.J., E-mail: [Nuclear Research and Consultancy Group, Westerduinweg 3, Postbus 25, 1755 ZG Petten (Netherlands); Jong, M.; Bakker, T.; Luzginova, N.V.; Mutnuru, R.K.; Ketema, D.J.; Fedorov, A.V. [Nuclear Research and Consultancy Group, Westerduinweg 3, Postbus 25, 1755 ZG Petten (Netherlands)


    In the framework of the materials domain DEMETRA in the European Transmutation research and development project EUROTRANS, irradiation experiment IBIS has been performed in the High Flux Reactor in Petten. The objective was to investigate the synergystic effects of irradiation and lead bismuth eutectic exposure on the mechanical properties of structural materials and welds. In this experiment ferritic martensitic 9 Cr steel, austenitic 316L stainless steel and their welds have been irradiated for 250 Full Power Days up to a dose level of 2 dpa. Irradiation temperatures have been kept constant at 300 deg. C and 500 deg. C. During the post-irradiation test phase, tensile tests performed on the specimens irradiated at 300 deg. C have shown that the irradiation hardening of ferritic martensitic 9 Cr steel at 1.3 dpa is 254 MPa, which is in line with the irradiation hardening obtained for ferritic martensitic Eurofer97 steel investigated in the fusion program. This result indicates that no LBE interaction at this irradiation temperature is present. A visual inspection is performed on the specimens irradiated in contact with LBE at 500 deg. C and have shown blackening on the surface of the specimens and remains of LBE that makes a special cleaning procedure necessary before post-irradiation mechanical testing.

  16. System and safety studies of accelerator driven systems for transmutation. Annual report 2008

    Energy Technology Data Exchange (ETDEWEB)

    Arzhanov, Vasily; Bergloef, Calle; Fokau, Andrei; Jolkkonen, Mikael; Runevall, Odd; Sandberg, Nils; Tesinsky, Milan; Wallenius, Janne; Youpeng Zhang (Div. of Reactor Physics, Royal Institute of Technology, Stockholm (Sweden))


    Within this project, research on design and safety of subcritical reactors for recycling of minor actinides is performed. During 2008, the reactor physics division at KTH has made a design study of a source efficient ADS with nitride fuel, based on the EFIT design made within the EUROTRANS project. Transient analysis for EFIT-400 ADS with cercer and cermet fuels was made with SAS4A, taking into account flow reversal phenomena. Using Pulsed Neutron Source techniques, reference reactivity values for detectors in the sub-critical YALINA booster facility were obtained and it was observed that the results carry strong spatial effects. It was shown that the beam trip technique can be used to obtain the reactivity at beam trips and the values can be used for calibration of a current-to-flux reactivity indicator. Multi-scale modelling of helium desorption from molybdenum was performed, with the final aim to predict the in-pile behaviour of Mo based CERMET fuel. Good agreement with experimental data was obtained, except at the highest temperatures

  17. Experimental results from the VENUS-F critical reference state for the GUINEVERE accelerator driven system project

    Energy Technology Data Exchange (ETDEWEB)

    Uyttenhove, W.; Baeten, P.; Ban, G.; Billebaud, A.; Chabod, S.; Dessagne, P.; Kerveno, M.; Kochetkov, A.; Lecolley, F. R.; Lecouey, J. L.; Marie, N.; Mellier, F.; Steckmeyer, J. C.; Thyebault, H. E.; Vittiglio, G.; Wagemans, J. [SCK.CEN, Belgian Nuclear Research Centre, Boeretang 200, BE-2400 Mol (Belgium)


    The GUINEVERE (Generation of Uninterrupted Intense Neutron pulses at the lead Venus Reactor) project was launched in 2006 within the framework of FP6 EUROTRANS in order to validate on-line reactivity monitoring and subcriticality level determination in Accelerator Driven Systems. Therefore the VENUS reactor at SCK.CEN in Mol (Belgium) was modified towards a fast core (VENUS-F) and coupled to the GENEPI-3C accelerator built by CNRS The accelerator can operate in both continuous and pulsed mode. The VENUS-F core is loaded with enriched Uranium and reflected with solid lead. A well-chosen critical reference state is indispensable for the validation of the on-line subcriticality monitoring methodology. Moreover a benchmarking tool is required for nuclear data research and code validation. In this paper the design and the importance of the critical reference state for the GUINEVERE project are motivated. The results of the first experimental phase on the critical core are presented. The control rods worth is determined by the rod drop technique and the application of the Modified Source Multiplication (MSM) method allows the determination of the worth of the safety rods. The results are implemented in the VENUS-F core certificate for full exploitation of the critical core. (authors)

  18. The GUINEVERE project at the VENUS-F Facility

    Energy Technology Data Exchange (ETDEWEB)

    Baeten, P.; Ait Abderrahim, H.; Bergmans, G.; Kochetkov, A.; Uyttenhove, W.; Vandeplassche, D.; Vermeersch, F.; Vittiglio, G. [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium); Ban, G.; Baylac, M.; Billebaud, A.; Bondoux, D.; Bouvier, J.; Chabod, S.; De Conto, J.M.; Dessagne, P.; Gaudiot, G.; Gautier, J.M.; Heitz, G.; Kerveno, M.; Laune, B.; Lecolley, F.R.; Lecouey, J.L.; Marie, N.; Merrer, Y.; Nuttin, A.; Reynet, D.; Steckmeyer, J.C. [CNRS-IN2P3 (France); Mellier, F. [CEA/DEN/SPeX/LPE, CEN Cadarache, F-13104 Saint-Paul-lez-Durance (France)


    Within the framework of the ECATS (Experimental activities on the Coupling of an Accelerator, a spallation Target and a Sub-critical blanket) research domain of the FP6 IP-EUROTRANS program, the GUINEVERE (Generation of Uninterrupted Intense Neutron pulses at the lead Venus Reactor) project was launched in 2006 in order to check in the experiments an open questions stay for the techniques used in the MUSE programme (CEA Cadarache, France, 2000-2004), related to the online reactivity monitoring, sub-criticality determination and operational procedure of an Accelerator Driven System. For this purpose, the VENUS light water critical reactor at the SCK-CEN site of Mol (Belgium) was modify into a subcritical fast core (VENUS-F) and the GENEPI accelerator, designed for the MUSE experiment was up-graded to the new GENEPI-3C accelerator. The VENUS-F coupled with the GENEPI-3C and a TiT target will provide a unique facility in Europe for fast sub-critical and critical reactor physics investigations. This paper describes the present status of the facility. (authors)

  19. Optimized tuning of contention window for IEEE 802.11 WLAN ...

    African Journals Online (AJOL)

    In wireless networks, the size of Contention Window (CW) plays a vital role as it changes the throughput and delay of the networks considerably. The proposed Collision Ratio based BackOff (CRBO) algorithm uses collision ratio to suggest CW updation after the successful and unsuccessful transmission events. This leads ...

  20. Effect of carbide waste on the properties of rice husk ash concrete ...

    African Journals Online (AJOL)

    The impact of carbide waste,CW on the strength of concrete made with cement partially replaced with Rice Husk Ash,RHA for use in rigid pavement was investigated. Oxide composition analysis of CW and RHA confirm their status as non pozzolanic material rich in CaO component and pozzolanic materials, respectively.

  1. Removal of Nutrients from Septic Effluent with Re-circulated Hybrid Tidal Flow Constructed Wetland (United States)

    Lihua Cui; Jigkun Feng; Ying Ouyang; Peiwen. Deng


    Hybrid tidal flow constructed wetland (CW) with recirculation is an improved biological and engineering technique for removal of excess nutrients and certain pollutants from wastewater. This study investigated the removal efficiency of total phosphorus (TP), ammonia-nitrogen (NH3-N), and total nitrogen (TN) from septic tank effluent with the hybrid tidal flow CW system...

  2. High average power Q-switched 1314 nm two-crystal Nd:YLF laser

    CSIR Research Space (South Africa)

    Botha, RC


    Full Text Available A 1314 nm two-crystal Nd:YLF laser was designed and operated in both CW and actively Q-switched modes. Maximum CW output of 26.5 W resulted from 125 W of combined incident pump power. Active Q-switching was obtained by inserting a Brewster...

  3. Target Vapor Identification and Database Development. Task 1 Report (United States)


    Table 2-1 with CAS registry numbers, includes many historical CW agents as well as CW precursors whose only utility is the synthesis of Schedule 1...propylhexdedrine; 4 =methylamphetamine; 5 =nore phedrine; 6 = ephedrine; 7 = phenmetrazine; 8 =phendimetrazine; 9 amfepra mane; 10 = benzocaine ; 11

  4. Effects of a constructed wetland and pond system upon shallow groundwater quality (United States)

    Ying Ouyang


    Constructed wetland (CW) and constructed pond (CP) are commonly utilized for removal of excess nutrients and certain pollutants from stormwater. This study characterized shallow groundwater quality for pre- and post-CW and CP system conditions using data from monitoring wells. Results showed that the average concentrations of groundwater phosphorus (P) decreased from...

  5. Hypoxia-Targeting Fluorescent Nanobodies for Optical Molecular Imaging of Pre-Invasive Breast Cancer

    NARCIS (Netherlands)

    van Brussel, Aram S A; Adams, Arthur; Oliveira, Sabrina; Dorresteijn, Bram; El Khattabi, Mohamed; Vermeulen, J. F.; van der Wall, Elsken; Mali, Willem P Th M; Derksen, Patrick W B; van Diest, Paul J; van Bergen En Henegouwen, Paul M P

    PURPOSE: The aim of this work was to develop a CAIX-specific nanobody conjugated to IRDye800CW for molecular imaging of pre-invasive breast cancer. PROCEDURES: CAIX-specific nanobodies were selected using a modified phage display technology, conjugated site-specifically to IRDye800CW and evaluated

  6. Hypoxia-Targeting Fluorescent Nanobodies for Optical Molecular Imaging of Pre-Invasive Breast Cancer

    NARCIS (Netherlands)

    van Brussel, Aram S A; Adams, Arthur; Oliveira, Sabrina; Dorresteijn, Bram; El Khattabi, Mohamed; Vermeulen, Jeroen F.|info:eu-repo/dai/nl/338877169; van der Wall, Elsken; Mali, W.P.T.M.; Derksen, Patrick W B|info:eu-repo/dai/nl/256054797; van Diest, Paul J.|info:eu-repo/dai/nl/075281775; van Bergen En Henegouwen, Paul M P

    Purpose: The aim of this work was to develop a CAIX-specific nanobody conjugated to IRDye800CW for molecular imaging of pre-invasive breast cancer. Procedures: CAIX-specific nanobodies were selected using a modified phage display technology, conjugated site-specifically to IRDye800CW and evaluated

  7. Mechanophores for Self-Healing Applications (United States)


    Healing Applications active species in ROMP. Organometallics, 31 (6), 2476–2481. 59 Tennyson , A.G., Wiggins, K.M., and Bielawski, C.W. (2010) Mechanical... Tennyson , A.G., and Bielawski, C.W. (2011) Selective scission of pyridine-boronium complexes: mechanical generation of brønsted bases and

  8. Het interieurjaar 2001

    Directory of Open Access Journals (Sweden)

    B. de Vries


    Full Text Available R. Baarsen, Rococo in Nederland F. van Burkom, Leven in toen. Vier eeuwen Nederlands interieur in beeld H.C.M. Kleijn, Interieurs belicht: M. Westermann, C.W. Fock, E.J. Sluijter, H.P. Chapman, Art and home. Dutch interiors in the age of Rembrandt C.W. Fock, Het Nederlandse interieur in beeld 1600-1900

  9. Removal Efficiency of Constructed Wetland for Treatment of Agricultural Wastewaters

    Directory of Open Access Journals (Sweden)

    Michal Šereš


    Full Text Available This study describes performance of a hybrid constructed wetland (CW for treating wastewater from small farm in Czech Republic. The CW consisting of two horizontal filters, one vertical filter and three shallow pondsand reduced inflow values of 25.400 mg/L COD and 2.640 mg/L BOD5 by up to 99%.

  10. AcEST: DK946315 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sulfoxide reductase msrA... 31 3.7 sp|A3CW67|PYRI_METMJ Aspartate carbamoyltransf... F+ GR+IRP Sbjct: 8 SALPDPH-DALPGRATPLQVTETHFVHGRRIRP 39 >sp|A3CW67|PYRI_METMJ Aspartate carbamoyltransferas

  11. Design and Season Influence Nitrogen Dynamics in Two Surface Flow Constructed Wetlands Treating Nursery Irrigation Runoff

    Directory of Open Access Journals (Sweden)

    Sarah A. White


    Full Text Available Constructed wetlands (CWs are used to remediate runoff from a variety of agricultural, industrial, and urban sources. CW remediation performance is often evaluated at the laboratory scale over durations less than one year. The purpose of this study was to characterize the effect of CW design (cell depth and residence time on nitrogen (N speciation and fate across season and years in two free water surface wetlands receiving runoff from irrigated plant production areas at an ornamental plant nursery. Water quality (mg·L−1 of nitrate, nitrite, and ammonium, dissolved oxygen and oxidation reduction potential was monitored at five sites within each of two CWs each month over four years. Nitrate-N was the dominant form of ionic N present in both CWs. Within CW1, a deep cell to shallow cell design, nitrate comprised 86% of ionic N in effluent. Within CW2, designed with three sequential deep cells, nitrate comprised only 66% of total N and ammonium comprised 27% of total N in CW2 effluent. Differences in ionic N removal efficacies and shifts in N speciation in CW1 and CW2 were controlled by constructed wetland design (depth and hydraulic retention time, the concentration of nutrients entering the CW, and plant species richness.

  12. Screening for Trauma Exposure, and Posttraumatic Stress Disorder and Depression Symptoms among Mothers Receiving Child Welfare Preventive Services (United States)

    Chemtob, Claude M.; Griffing, Sascha; Tullberg, Erika; Roberts, Elizabeth; Ellis, Peggy


    The role of parental trauma exposure and related mental health symptoms as risk factors for child maltreatment for parents involved with the child welfare (CW) system has received limited attention. In particular, little is known about the extent to which mothers receiving CW services to prevent maltreatment have experienced trauma and suffered…

  13. Effects of gamma irradiation on cell-wall constituents of some agricultural residues

    Energy Technology Data Exchange (ETDEWEB)

    Al-Masri, M.R.; Zarkawi, M. [Atomic Energy Commission, Damascus (Syrian Arab Republic)


    The effects of 150 kilogray (kGy) of {gamma} irradiation on cell-wall constituents of cottonwood (CW), lentils straw (LS), apple pruning products (AP) and olive cake (OC) were investigated. Samples were irradiated by {gamma} irradiation at a dose level of 150 kGy under identical conditions of temperature and humidity and analyzed for crude fibre (CF), neutral-detergent fibre (NDF), acid detergent fibre (ADF) and acid-detergent lignin (ADL). The results indicate that {gamma} irradiation decreased CF contents by about 29% for CW, LS and AP and by 17% for OC. NDF values were also decreased by about 4% for CW and OC, and by about 12% for LS and AP. {gamma} irradiation treatment also decreased ADF values only for CW by 8%. ADL contents decreased by 8% for CW and 5% for OC with no effects for LS and AP. The percentage of cellulose (CL):CF ratio increased by 30, 34, 38 and 20% for CW, LS, AP and OC, respectively. Also, the percentage of hemicellulose (HCL):CF increased for 57% for CW and 16% for OC and decreased by 7% for LS and AP. The percentage of HCL:ADL increased by 22% for CW but decreased by 33% for LS and AP with no changes for OC. There were no changes in CL:ADL ratio for all residues. (Author).

  14. Generation of pulsed light in the visible spectral region based on non-linear cavity dumping

    DEFF Research Database (Denmark)

    Johansson, Sandra; Andersen, Martin; Tidemand-Lichtenberg, Peter

    We propose a novel generic approach for generation of pulsed light in the visible spectrum based on sum-frequency generation between the high circulating intra-cavity power of a high finesse CW laser and a single-passed pulsed laser. For demonstration, we used a CW 1342 nm laser mixed with a pass...

  15. Morse theory for C*-algebras: a geometric interpretation of some noncommutative manifolds

    Directory of Open Access Journals (Sweden)

    Vida Milani


    Full Text Available The approach we present is a modification of the Morse theory for unital C*-algebras. We provide tools for the geometric interpretation of noncommutative CW complexes. Some examples are given to illustrate these geometric information. The main object of this work is a classification of unital C*-algebras by noncommutative CW complexes and the modified Morse functions on them.

  16. Towards filament free semiconductor lasers

    DEFF Research Database (Denmark)

    McInerney, John; O'Brien, Peter; Skovgaard, Peter M. W.


    We outline physical models and simulations for suppression of self-focusing and filamentation in large aperture semiconductor lasers. The principal technical objective is to generate multi-watt CW or quasi-CW outputs with nearly diffraction limited beams, suitable for long distance free space...... propagation structures in lasers and amplifiers which suppress lateral reflections....

  17. Attention Demand and Postural Control in Children with Hearing Deficit (United States)

    Derlich, Malgorzata; Krecisz, Krzysztof; Kuczynski, Michal


    To elucidate the mechanisms responsible for deteriorated postural control in children with hearing deficit (CwHD), we measured center-of-pressure (COP) variability, mean velocity and entropy in bipedal quiet stance (feet together) with or without the concurrent cognitive task (reaction to visual stimulus) on hard or foam surface in 29 CwHD and a…

  18. Application of random regression models to the genetic evaluation ...

    African Journals Online (AJOL)

    Estimates of genetic correlations were greater than 0.82 among measures of weight at all ages. The resulting covariance functions were used to estimate breeding values of each animal along the age trajectory. Genetic trends for CW over the years showed only a slightly increasing pattern, suggesting that CW did not ...

  19. Preliminary design of high-power wave-guide/transmission system ...

    Indian Academy of Sciences (India)

    . This LINAC will be needing CW rf power in the frequency ranges of 350 MHz and 700 MHz for its RFQ and. DTL/CCDTL/SFDTL structures respectively. The power to the accelerating structures will be pro- duced by either 1 MW CW or 250 kW ...

  20. Performance of Subsurface Flow Constructed Wetland for Domestic ...

    African Journals Online (AJOL)

    Constructed wetlands (CW) have recently emerged as efficient technology for secondary treatment of wastewater in developing countries because of its low cost, ease operation, maintenance and generally good performance. At present there are a number of small scale units of CW for wastewater treatment in Tanzania but ...

  1. performance of subsurface flow constructed wetland for domestic

    African Journals Online (AJOL)


    ABSTRACT. Constructed wetlands (CW) have recently emerged as efficient technology for secondary treatment of wastewater in developing countries because of its low cost, ease operation, maintenance and generally good performance. At present there are a number of small scale units of CW for wastewater treatment in ...

  2. Capillary waves and the decay of density correlations at liquid surfaces. (United States)

    Hernández-Muñoz, Jose; Chacón, Enrique; Tarazona, Pedro


    Wertheim predicted strong density-density correlations at free liquid surfaces, produced by capillary wave fluctuations of the interface [M. S. Wertheim, J. Chem. Phys. 65, 2377 (1976)JCPSA60021-960610.1063/1.433352]. That prediction has been used to search for a link between capillary wave (CW) theory and density functional (DF) formalism for classical fluids. In particular, Parry et al. have recently analyzed the decaying tails of these CW effects moving away from the interface as a clue for the extended CW theory [A. O. Parry et al., J. Phys.: Condens. Matter 28, 244013 (2016)JCOMEL0953-898410.1088/0953-8984/28/24/244013], beyond the strict long-wavelength limit studied by Wertheim. Some apparently fundamental inconsistencies between the CW and the DF theoretical views of the fluid interfaces arose from the asymptotic analysis of the CW signal. In this paper we revisit the problem of the CW asymptotic decay with a separation of local non-CW surface correlation effects from those that are a truly nonlocal propagation of the CW fluctuations from the surface towards the liquid bulk.

  3. Vegetation type and layer depth influence nitrite-dependent methane-oxidizing bacteria in constructed wetland. (United States)

    Yang, Mengxi; Guo, Qingwei; Tong, Tianli; Li, Ningning; Xie, Shuguang; Long, Yan


    Nitrite-dependent anaerobic methane oxidation (n-damo) process might be an important methane sink in wetland system. However, information on n-damo microorganisms in constructed wetland (CW) system for water treatment is still lacking. The present study investigated the n-damo communities in five full-scale vertical-flow CW systems with different plants. N-damo bacterial abundance did not show a considerable shift in CW planted with Cyperus papyrus, but varied greatly in other CW systems. However, the evident vertical change of n-damo community diversity occurred in each CW system. These CW systems displayed the different vertical change trends for either n-damo community abundance or diversity. In addition, CW n-damo community structure could change with wetland layer depth. At a given wetland layer depth, the evident difference of n-damo community abundance, diversity and structure could be observed in the five different CW systems. Both wetland layer depth and vegetation type could contribute to the shift of n-damo bacterial abundance and community structure in CWs.

  4. Innovativt skole-praktiksamarbejde i social- og sundhedsuddannelserne

    DEFF Research Database (Denmark)

    Wegener, Charlotte


    Pixi-udgave af PhD-afhandlingen 'Innovation - inside out'. Kan rekvireres ved henvendelse til forfatteren på af PhD-afhandlingen 'Innovation - inside out'. Kan rekvireres ved henvendelse til forfatteren på

  5. Performance assessment of aeration and radial oxygen loss assisted cathode based integrated constructed wetland-microbial fuel cell systems. (United States)

    Srivastava, Pratiksha; Dwivedi, Saurabh; Kumar, Naresh; Abbassi, Rouzbeh; Garaniya, Vikram; Yadav, Asheesh Kumar


    The present study explores low-cost cathode development possibility using radial oxygen loss (ROL) of Canna indica plants and intermittent aeration (IA) for wastewater treatment and electricity generation in constructed wetland-microbial fuel cell (CW-MFC) system. Two CW-MFC microcosms were developed. Amongst them, one microcosm was planted with Canna indica plants for evaluating the ROL dependent cathode reaction (CW-MFC dependent on ROL) and another microcosm was equipped with intermittent aeration for evaluating the intermittent aeration dependent cathode reaction (CW-MFC with additional IA). The CW-MFC with additional IA has achieved 78.71% and 53.23%, and CW-MFC dependent on ROL has achieved 72.17% and 46.77% COD removal from synthetic wastewater containing glucose loads of 0.7gL-1and 2.0gL-1, respectively. The maximum power density of 31.04mWm-3 and 19.60mWm-3 was achieved in CW-MFC with additional IA and CW-MFC dependent on ROL, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. On the shape of continuous wave infrared stimulated luminescence signals from feldspars: A case study

    DEFF Research Database (Denmark)

    Pagonis, V.; Jain, Mayank; Thomsen, Kristina Jørkov


    The continuous-wave IRSL (CW-IRSL) signals from feldspars are known to decay in a non-exponential manner, and their exact mathematical description is of great importance in dosimetric and dating studies. This paper investigates the possibility of fitting experimental CW-IRSL curves from a variety...

  7. Why All Writing Is Creative Writing (United States)

    McVey, David


    Creative Writing (CW) courses and degrees are growing in numbers and influence. They are fashionable for students to enrol on, fashionable for institutions to offer. CW courses have an established track record in producing successful novelists, bring new challenges in reconciling creativity and conformity, and provide a useful source of employment…

  8. High average power 1314 nm Nd:YLF laser, passively Q-switched with V:YAG

    CSIR Research Space (South Africa)

    Botha, RC


    Full Text Available A 1314 nm Nd:YLF laser was designed and operated both CW and passively Q-switched. Maximum CW output of 10.4 W resulted from 45.2 Wof incident pump power. Passive Q-switching was obtained by inserting a V:YAG saturable absorber in the cavity...

  9. Proteins Play Important Role in Intercellular Adhesion Affecting on Fruit Textural Quality

    DEFF Research Database (Denmark)

    Bahadur Adhikari, Khem; Shomer, Ilan


    Fruit textural quality is becoming a major quality parameter for export, postharvest preservation, handling and processing. The main determinant of textural quality is intercellular adhesion (ICA) as attributed by the cell wall (CW) and its components. The importance of CW protein in ICA strength...

  10. Written Language Skills in Children with Specific Language Impairment (United States)

    Williams, Gareth J.; Larkin, Rebecca F.; Blaggan, Samarita


    Background: Young children are often required to carry out writing tasks in an educational context. However, little is known about the patterns of writing skills that children with specific language impairment (CwSLI) have relative to their typically developing peers. Aims: To assess the written language skills of CwSLI and compare these with…

  11. The influence of complex fermentation broth on denitrification of saline sewage in constructed wetlands by heterotrophic nitrifying/aerobic denitrifying bacterial communities. (United States)

    Fu, Guiping; Yu, Tianyu; Huangshen, Linkun; Han, Jingyi


    An experimental vertical-flow constructed wetland (CW) was tested to treat salt-containing sewage. CW clogging deposits and withered Pontederia cordata L. were collected into a complex fermentation broth to serve as the carbon source and its effects on the denitrification capacity and microbial composition of the CW were examined. Addition of the complex fermentation broth into the CW influent (1.8% salinity) led to high removal efficiencies of NH 4 + -N > 99.82 ± 0.00% and TN > 90.39 ± 0.05%. Heterotrophic nitrifiers and aerobic denitrifiers were entirely dominant in the middle and upper layers of the CW, where obligate halophilic, aerobic denitrifiers Zobellella occurred. The CW successfully cultivated and enriched heterotrophic nitrifying-aerobic denitrifying bacteria, overcoming the effects of salinity and insufficient organic carbon sources on the denitrification capacity of CW. This type of complex carbon sources can also facilitate the utilization of waste resources, such as CW clogging deposits and withered wetland plants. Copyright © 2017. Published by Elsevier Ltd.

  12. Two atoms scattering at low and cold energies

    Indian Academy of Sciences (India)

    1National Institute of Technical Teachers' Training and Research Kolkata, Salt Lake City,. Kolkata 700 106, India. 2New Alipore College, New Alipore, Kolkata 700 ... determine the strength of effective interatomic potential, as van der Waals interaction is defined as. Vvan(R) = −. CW. R6 ,. (1) where CW is the van der Waals ...

  13. Mission Suitability Testing of an Aircraft Simulator (United States)


    device. Peripheral equipments associated with the computer include a high-speed paper tape In/Ouf device, three keyboard printers, and two rapid...Examiners Piety, Richard L. CW4 8 Nov71 - 20Jan72 York, John CW4 8 Nov 71 - 20 Jan 72 Dvorak , Donald W. DAC 8 Nov71 - 20 Jan 72 Ketchum, Clark DAC 8

  14. 15 CFR 742.18 - Chemical Weapons Convention (CWC or Convention). (United States)


    ... Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION... controlled under ECCN 1C351.d.5 or d.6 to all destinations including Canada. CW applies to 1C351.d.5 for...) Technology controlled under ECCN 1E355. A license is required for CW reasons to export or reexport technology...

  15. Types of the cerebral arterial circle (circle of Willis in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Gunasekera WSL


    Full Text Available Abstract Background The variations of the circle of Willis (CW are clinically important as patients with effective collateral circulations have a lower risk of transient ischemic attack and stroke than those with ineffective collaterals. The aim of the present cadaveric study was to investigate the anatomical variations of the CW and to compare the frequency of prevalence of the different variations with previous autopsy studies as variations in the anatomy of the CW as a whole have not been studied in the Indian subcontinent. Methods The external diameter of all the arteries forming the CW in 225 normal Sri Lankan adult cadaver brains was measured using a calibrated grid to determine the prevalence in the variation in CW. Chisquared tests and a correspondence analysis were performed to compare the relative frequencies of prevalence of anatomical variations in the CW across 6 studies of diverse ethnic populations. Results We report 15 types of variations of CW out of 22 types previously described and one additional type: hypoplastic precommunicating part of the anterior cerebral arteries (A1 and contralateral posterior communicating arteries (PcoA 5(2%. Statistically significant differences (p Conclusion The present study reveals that there are significant variations in the CW among intra and inter ethnic groups (Caucasian, African and Asian: Iran and Sri Lanka dominant populations, and warrants further studies keeping the methods of measurements, data assessment, and the definitions of hypoplasia the same.

  16. Molecular Characterization and Potential of Bacterial Species ...

    African Journals Online (AJOL)

    Knowledge of the true microbial diversity in cassava waste (CW) is fundamental to effective utilization of this waste. This paper reports, on the identification of bacteria species associated with CW, using molecular tools. The 16S rRNA gene of total bacteria community and bacterial isolates were amplified by Polymerase ...

  17. Reduction of pattern effects in SOA-based all-optical switches by using cross-gain modulated holding signal

    DEFF Research Database (Denmark)

    Bischoff, Svend; Mørk, Jesper


    The effective carrier lifetime of SOAs is typically shortened by an intense Continuous Wave (CW) holding signal. However, the SOA gain is reduced by the holding signal resulting in smaller gain and refractive index changes induced by the data signal. Accordingly, an optimum exists for the CW and ...

  18. The effect of air permeability of chemical protective clothing material on clothing vapour resistance

    NARCIS (Netherlands)

    Havenith, G.; Vuister, R.; Wammes, L.


    One of the major problems associated with Chemical Warfare Protective Clothing (CW) is the additional heat load created by the garments. For CW-overgarments, research in the direction of reducing material thickness and thus heat and vapour resistance have not resulted in major improvements. The

  19. Phytoremediation of domestic wastewaters in free water surface constructed wetlands using Azolla pinnata. (United States)

    Akinbile, Christopher O; Ogunrinde, Temitope A; Che Bt Man, Hasfalina; Aziz, Hamidi Abdul


    Two constructed wetlands, one with Azolla pinnata plant (CW1) and the other without (CW2) for treating domestic wastewaters were developed. Fifteen water parameters which include: Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Phosphorus (TP), Total Nitrogen (TN), Ammoniacal Nitrogen (NH3N), Turbidity, pH, Electrical Conductivity (EC), Iron (Fe), Magnesium (Mg), Manganese (Mn), and heavy metals such as Lead (Pb) and Zinc (Zn) were analyzed using standard laboratory procedures. The experiments were conducted in two (dry and wet) seasons simultaneously. Results showed considerable reductions in all parameters and metals including Zn in CW1 compared with CW2 in the two seasons considered while Pb and Mn were not detected throughout the study. Zn concentration levels reduced significantly in both seasons just as removal efficiencies of 70.03% and 64.51% were recorded for CW1 while 35.17% and 33.45% were recorded for CW2 in both seasons. There were no significant differences in the removal efficiencies of Fe in both seasons as 99.55%, 59.09%, 88.89%, and 53.56% were recorded in CW1 and CW2 respectively. Azolla pinnata has proved effective in domestic wastewater phytoremediation studies.

  20. Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India. (United States)

    Saha, S; Badhe, N; Seuntjens, D; Vlaeminck, S E; Biswas, R; Nandy, T


    The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87-98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5-2 d. The FUP-CW removed 68.5±13% COD, 68±3% NH4+-N, 38±5% PO4(3-)-P, 97.6±5% suspended particles and 97±13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process.

  1. An Experimental Comparison of CLOS and C++ Implementations of An Object- Oriented Graphical Simulation of Walking Robot Kinematics (United States)


    iina (camera-window camera) (cw:maks-Position :x (first start) :y (second start)) (cw make-position -.x (first end) :y (second end)) : brush -width 0...Rotate (double angle) // Rotetelink (double angle) // AUTHOR: S L Davidson /1 DATE: 10Sept 92 // .*etetet..*.*** teet ~t.**.***,..**.*tt~tetetoeteett

  2. Low Factual Understanding and High Anxiety about Climate Warming Impedes University Students to Become Sustainability Stewards: An Australian Case Study (United States)

    Pfautsch, Sebastian; Gray, Tonia

    Purpose: This study, from Western Sydney University, aims to assess the disposition of students towards climate warming (CW)--a key component of sustainability. CW is a global reality. Any human born after February 1985 has never lived in a world that was not constantly warming, yet little is known about how higher education students perceive…

  3. Single frequency intracavity SRO

    DEFF Research Database (Denmark)

    Abitan, Haim; Buchhave, Preben


    Summary form only given. A single resonance optical parametric oscillator (SRO) is inserted intracavity to a CW high power, single frequency, and ring Nd:YVO4 laser. We obtain a stable single frequency CW SRO with output at 1.7-1.9 μm (idler) and a resonating signal at 2.3-2.6 μm. The behavior...

  4. The incidence and severity of injuries at the 2011 South African ...

    African Journals Online (AJOL)

    In general, there was a higher proportion of concussions at the GK16, AW18, and CW18 compared with the CW13 tournament(s). Conclusions. Time-loss IIDs at SARU Youth Weeks are similar to other elite junior rugby data. The absolute number and type/ classification of injuries per match may be more informative than ...

  5. Joint Force Quarterly. Number 18, Spring 1998 (United States)


    players reveal an entirely different persona when acting as Blue planners trying to cope with a Red CW/BW warplan. They downplay CW/BW effects on Blue...tures a JEL CD–ROM updated monthly by the Joint Doctrine Division (J-7), which welcomes comments and sug- gestions from members of the Joint Staff

  6. Curcumin prevents muscle damage by regulating NF-κB and Nrf2 pathways and improves performance: an in vivo model (United States)

    Sahin, Kazim; Pala, Ragip; Tuzcu, Mehmet; Ozdemir, Oguzhan; Orhan, Cemal; Sahin, Nurhan; Juturu, Vijaya


    Purpose Exercise (Ex) increases reactive oxygen species and impairs antioxidant defense systems. Recent data suggest that curcumin (CW) possesses peroxisome proliferator-activated receptor gamma activity and anti-inflammatory properties. Therefore, this study was designed to investigate the effects of CW supplementation on Ex performance, endurance, and changes in serum and muscle proteins in rats after exhaustive Ex. Materials and methods Twenty-eight (28) male Wistar rats (age: 8 weeks and body weight: 180±20 g) were divided into four treatment groups: 1) control (C; no Ex), 2) C + CW (no Ex + CW), 3) C + Ex, and 4) C + Ex + CW (Ex + CW). CW was administered as 100 mg/kg CurcuWin®, providing 20 mg of curcuminoids daily for 6 weeks. A motor-driven rodent treadmill was used to carry out the Ex protocols. During a 5-day period, animals in chronic Ex groups were put through different regimens: day 1, 10 m/min for 10 minutes; day 2, 20 m/min for 10 minutes; day 3, 25 m/min for 10 minutes; day 4, 25 m/min for 20 minutes; and day 5, 25 m/min for 30 minutes. Animals were exercised at 25 m/min for 45 min/d for 5 d/wk for 6 weeks. Blood and muscle samples were analyzed for muscle markers, oxidative stress, and antioxidant markers. Results Lactate and muscle malondialdehyde levels decreased in the CW-treated groups (P<0.0001). However, activities of antioxidant enzyme levels increased in the CW-treated groups. Run to exhaustion (minutes) improved in the CW-treated groups. Muscle nuclear factor-κB (P<0.05) and heat shock protein 70 (P<0.05) levels were much lowered in the CW treated group followed by Ex group. In addition, muscle inhibitors of kappa B, peroxisome proliferator-activated receptor gamma coactivator 1-alpha, thioredoxin-1, sirtuin 1, nuclear factor (erythroid-derived 2)-like 2, and glucose transporter 4 protein levels in the Ex + CW group were higher than those in the control and Ex groups (P<0.05). Conclusion This study suggests that novel CW has the

  7. Model development, testing and experimentation in a CyberWorkstation for Brain-Machine Interface research. (United States)

    Rattanatamrong, Prapaporn; Matsunaga, Andrea; Raiturkar, Pooja; Mesa, Diego; Zhao, Ming; Mahmoudi, Babak; Digiovanna, Jack; Principe, Jose; Figueiredo, Renato; Sanchez, Justin; Fortes, Jose


    The CyberWorkstation (CW) is an advanced cyber-infrastructure for Brain-Machine Interface (BMI) research. It allows the development, configuration and execution of BMI computational models using high-performance computing resources. The CW's concept is implemented using a software structure in which an "experiment engine" is used to coordinate all software modules needed to capture, communicate and process brain signals and motor-control commands. A generic BMI-model template, which specifies a common interface to the CW's experiment engine, and a common communication protocol enable easy addition, removal or replacement of models without disrupting system operation. This paper reviews the essential components of the CW and shows how templates can facilitate the processes of BMI model development, testing and incorporation into the CW. It also discusses the ongoing work towards making this process infrastructure independent.

  8. Assessing the present in perspective of the past

    DEFF Research Database (Denmark)

    Gensby, Ulrik


    the extent to which the CW meth- odology can inform researchers involved in organizational development and change to ad- dress some potential limitations that exist. The CW encouraged the expression of diverse perspectives, incorporating insight from different organizational levels, and identified various......Participatory approaches to jointly address development and change processes are increas- ingly applied in Nordic working life research. One approach, the Chronicle Workshop (CW), aims at facilitating collective history through collaborative exploration and joint analysis of organizational...... development and change processes to guide forthcoming change. This study presents the CW methodology as an interactive research process. The study examines how the CW can facilitate mutual understanding and explanation of sickness absence and return to work efforts in the healthcare workplace, and discuss...

  9. Anaerobic digestion of cheese whey: Energetic and nutritional potential for the dairy sector in developing countries. (United States)

    Escalante, H; Castro, L; Amaya, M P; Jaimes, L; Jaimes-Estévez, J


    Cheese whey (CW) is the main waste generated in the cheesemaking process and has high organic matter content and acidity. Therefore, CW disposal is a challenge for small to medium enterprises (SMEs) in the dairy industry that do not have any type of treatment plant. Anaerobic digestion (AD) is an attractive process for solving this problem. The aim of this research was to determine the biomethane and struvite precipitation potentials of CW from four dairy SMEs. First, changes in CW properties (organic matter and pH) were evaluated. Second, biomethane and struvite potentials were assessed using cattle slurry as inoculum. The organic matter in CW varied from 40 to 65gVS/kg, 65 to 140g COD/L, and 2 to 10g/L for VFAs depending on the sampling time and type of sample. The pH of the CW samples ranged from 3 to 6.5. In the anaerobic biodegradability analysis, methane yields reached 0.51 to 0.60L CH4/g VSadded, which represented electrical and caloric potentials of 54 and 108kWh/m(3) for CW, respectively. Organic matter removal in all experiments was above 83%. Moreover, anaerobic digestates presented NH4(+)/PO4(3-) molar ratios between 2.6 and 4.0, which are adequate for struvite precipitation with potential production of 8.5-10.4g struvite/L CW. Finally, the use of biogas as energetic supplement and struvite as soil fertilizer, represents economics saves of US$ 6.91/m(3) CW and US$ 5.75/m(3) CW in therms of electricity and fertilizer use, respectively. The energetic, agricultural and economic potentials, evidence that AD process is a feasible alternative for cheese whey treatment. Copyright © 2017. Published by Elsevier Ltd.

  10. Effect of cold working on the aging and corrosion behavior of Fe-Mn-Al stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Ghayad, I.M.; Girgis, N.N.; Ghanem, W. [Central Metallurgical Research and Development Institute, CMRDI, P.O. Box 87, Helwan, Cairo (Egypt); Hamada, A.S. [Dept. of Metallurgy and Materials Eng., Faculty of Petrol. and Min. Eng., Suez Canal University, el-Shikg Zayed, 41522 Ismailia (Egypt)


    The cold working; aging process; and corrosion behavior of the Fe-Mn-Al stainless steel having a composition of Fe-29wt%Mn-3.5wt%Al-0.5wt%C were investigated. Three different groups of specimens of the alloy were subjected to different procedures of cold working and aging. The first group were cold worked then solution treated at 1100 deg. C for 24 hr, coded as CW+ST. The second group were cold worked, solution treated at 1100 deg. C for 24 hr then cold worked again, coded as CW+ST+CW. The third group were solution treated at 1100 deg. C for 24 hr then cold worked, coded as ST+CW. Subsequent aging treatments of the controlled-worked alloy showed age hardening similar to that reported for the solution-treated alloys. The strengthening of the experimental alloy due to the controlled-working and aging is discussed on the basis of microstructural observations and X-ray diffraction analysis. The corrosion behavior of the different groups of the alloy, CW+ST; CW+ST+CW; ST+CW, with their peak aged and over aged conditions has been examined in 3.5% NaCl solution. The electrochemical techniques, potentiodynamic polarization and Tafel plots were employed. All the alloy groups did not passivate in 3.5% NaCl solution and the major corrosion type observed was general corrosion. The peak aged and over aged of the CW+ST+CW exhibited higher corrosion rates due to the formation of ferrite phase that formed a galvanic couple with the austenitic matrix. (authors)

  11. Magnetic resonance angiographic evaluation of circle of Willis: A morphologic study in a tertiary hospital set up. (United States)

    Naveen, Shankar Rao; Bhat, Venkatraman; Karthik, Gadabanahalli Ashok


    Anatomy of circle of Willis (CW) shows wide variation in different individuals, population groups, and has vital clinical significance in causation and presentation of clinical disease. This study evaluates the anatomical variations, incidence of various common anomalies of CW in south Indian tertiary hospital set up, using three-dimensional time-of-flight (3D-TOF) magnetic resonance angiography (MRA). A total of 300 patients referred for neuroimaging study over a period of 2-year were included in the analysis. In this prospective and retrospective study, 198 men and 102 women; mean age, 55 years) underwent 3D-TOF MR angiograms of the CW using a 1.5-tesla MR scanner. Images were reviewed for anatomical configuration of the CW using maximum intensity projection (MIP) and 3D volume rendered images. On analysis, a complete CW was seen in 50 (16.6%) of 300 subjects. An incomplete anterior and posterior CW was found in 66 (22%) The remaining 184 (61.3%) subjects had partially complete CW configuration. The most common type of CW in a single subject was anterior variant type A and posterior type variant E. We observed wide variation in CW configuration in our patients. The prevalence of complete configuration of the circle is 16.6%; slightly higher in females and younger subjects. Complete anterior circle was present in 77.3%. Most common anterior variant is type A (normal anterior configuration) with a prevalence of 66%. The most common posterior circle variant is type E (hypoplasia or absence of both PcomA) with 32.6%. Overall, CW variants are slightly more common among the women in comparison to men. Incidence of associated anomalies like aneurysm or arteriovenous malformation (AVM) was comparable to that described in literature.

  12. Incidence of Dentinal Cracks after Root Canal Preparation with Twisted File Adaptive Instruments Using Different Kinematics. (United States)

    Karataş, Ertuğrul; Arslan, Hakan; Alsancak, Meltem; Kırıcı, Damla Özsu; Ersoy, İbrahim


    The purpose of the present study was to assess the effect of root canal instrumentation using Twisted File Adaptive instruments (Axis/SybronEndo, Orange, CA) with different kinematics (adaptive motion, 90° clockwise [CW]-30° counterclockwise [CCW], 150° CW-30° CCW, 210° CW-30° CCW, and continuous rotation) on crack formation. One hundred five mandibular central incisor teeth were selected. Fifteen teeth were left unprepared (control group), and the remaining 90 teeth were assigned to the 5 root canal shaping groups as follows (n = 15): adaptive motion, 90° CW-30° CCW, 150° CW-30° CCW, 210° CW-30° CCW, continuous rotation, and hand file. All the roots were sectioned horizontally at 3, 6, and 9 mm from the apex with a low-speed saw under water cooling, and the slices were then viewed through a stereomicroscope at 25× magnification. Digital images of each slice were captured using a camera to determine the presence of dentinal cracks. No cracks were observed in the control group, and the continuous rotation group had more cracks than the reciprocation groups (90° CW-30° CCW, 150° CW-30° CCW, and 210° CW-30° CCW) (P < .05). Both the continuous rotation and adaptive motion groups had significantly more dentinal cracks than the hand file group (P < .05). Regarding the different sections (3, 6, and 9 mm), there was a significant difference between the experimental groups at the 9-mm level (P < .05). The incidence of dentinal cracks is less with TF Adaptive instruments working in 210° CW-30° CCW reciprocating motion compared with working in continuous rotation and adaptive motion. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Preliminary design and economic investigations of Diffuser-Augmented Wind Turbines (DAWT)

    Energy Technology Data Exchange (ETDEWEB)

    Foreman, K.M.


    A preferred design and configuration approach is suggested for the DAWT innovative wind energy conversion system. A preliminary economic asessment is made for limited production rates of units between 5 and 150 kw rated output. Nine point designs are used to arrive at the conclusions regarding best construction material for the diffuser and busbar cost of electricity (COE). It is estimated that for farm and REA cooperative end users, the COE can range between 2 and 3.5 cents/kWh for sites with annual average wind speeds of 16 and 12 mph (25.7 and 19.3 km/h) respectively, and 150 kW rated units. No tax credits are included in these COE figures. For commercial end users of these 150 kW units the COE ranges between 4.0 and 6.5 cents/kWh for 16 and 12 mph sites. These estimates in 1979 dollars are lower than DOE goals set in 1978 for the rating size and end applications. Recommendations are made for future activities to maintain steady, systematic progress toward mature development of the DAWT.

  14. Removal of selected emerging PPCP compounds using greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland. (United States)

    Li, Jianan; Zhou, Qizhi; Campos, Luiza C


    Greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland (CW) was employed for removing four emerging pharmaceuticals and personal care products (PPCPs) (i.e. DEET, paracetamol, caffeine and triclosan). Orthogonal design was used to test the effect of light intensity, aeration, E.coli abundance and plant biomass on the target compounds. Synthetic wastewater contaminated with the target compounds at concentration of 25 μg/L was prepared, and both batch and continuous flow experiments were conducted. Up to 100% removals were achieved for paracetamol (PAR), caffeine (CAF) and tricolsan (TCS) while the highest removal for DEET was 32.2% in batch tests. Based on orthogonal Duncan analysis, high light intensity (240 μmolmm -2 s -1 ), full aeration, high plant biomass (1.00 kg/m 2 ) and high E.coli abundance (1.0 × 10 6  CFU/100 mL) favoured elimination of the PPCPs. Batch verification test achieved removals of 17.1%, 98.8%, 96.4% and 95.4% for DEET, PAR, CAF and TCS respectively. Continuous flow tests with CW only and CW followed by stabilization tank (CW-ST) were carried out. Final removals of the PPCP contaminants were 32.6%, 97.7%, 98.0% and 100% for DEET, PAR, CAF and TCS, respectively, by CW system alone, while 43.3%, 97.5%, 98.2% and 100%, respectively, were achieved by CW-ST system. By adding the ST tank, PPCP concentrations decreased significantly faster (p < 0.05) compared with continuous flow CW alone. In addition, after removing aerators during continuous flow CW experiments, the treatment systems presented good stability for the PPCP removals. CW-ST showed better chemical oxygen demand (COD) and total organic carbon (TOC) removals (89.3%, 91.2%, respectively) than CW only (79.4%, 85.2%, respectively). However, poor DEET removal (<50%) and high E.coli abundance (up to 1.7 log increase) in the final treated water indicated further treatment processes may be required. Statistical analysis showed significant correlations

  15. Bio-cathode materials evaluation and configuration optimization for power output of vertical subsurface flow constructed wetland - microbial fuel cell systems. (United States)

    Liu, Shentan; Song, Hailiang; Wei, Size; Yang, Fei; Li, Xianning


    To optimize the performance of a vertical subsurface flow constructed wetland-microbial fuel cell (CW-MFC), studies of bio-cathode materials and reactor configurations were carried out. Three commonly used bio-cathode materials including stainless steel mesh (SSM), carbon cloth (CC) and granular activated carbon (GAC) were compared and evaluated. GAC-SSM bio-cathode achieved the highest maximum power density of 55.05 mWm(-2), and it was most suitable for CW-MFCs application because of its large surface area and helpful capillary water absorption. Two types of CW-MFCs with roots were constructed, one was placed in the anode and the other was placed in the cathode. Both planted CW-MFCs obtained higher power output than non-planted CW-MFC. Periodic voltage fluctuations of planted CW-MFCs were caused by light/dark cycles, and the influent substrate concentration significantly affected the amplitude of oscillation. The coulombic efficiencies of CW-MFCs decreased greatly with the increase of the influent substrate concentration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Humoral antibody response to glutaraldehyde-treated antigens of Dermatophilus congolensis. (United States)

    Makinde, A A; Molokwu, J U; Ezeh, A O


    Glutaraldehyde-treated whole cell antigens (GA.WcA) of Dermatophilus congolensis induced in guinea pigs immunological memory in contrast to cell wall antigens treated similarly (GA.CwA). However, GA.WcA could not induce a secondary response in animals primed with untreated WcA while GA.CwA on the other hand did stimulate a secondary response in animals primed with untreated CwA. Primary antibody production was induced by both GA.CwA and untreated CwA to a similar level in their respective hosts but it was the secondary response that was found similar in response to GA.WcA and untreated WcA. However, both untreated WcA and CwA induced primary and secondary antibody production in their respective hosts though these responses were considerably higher in guinea pigs given untreated CwA. This study showed that both untreated and GA-treated antigens of D. congolensis are capable of stimulating antibody production in guinea pigs but they differ in their levels of stimulation.

  17. [Construction and Fluorescence Analysis of the Recombinant Listeria ivanovii Strain Expressing Green Fluorescent Protein]. (United States)

    Zhang, Xiang; Su, Lin; Liu, Si-Jing; Li, Yong-Yu; Jiang, Ming-Juan; Huang, Huan; Wang, Chuan


    Constructing the recombinant Listeria ivanovii strain expressing green fluorescent protein to provide an important tool for study of Listeria ivanovii. The promoter of Listeria monocytogenes Listeriolysin O (phly) and the green fluorescent protein (GFP) gene were fused by SOEing PCR,and then ligated the fusion gene into plasmid pCW to result in recombinant plasmid pCW-phly-GFP. Recombinant plasmid was electroporated into Listeria ivanovii,and fluorescence microscope was used to analyze the expression of GFP. To observe the stability of recombinant plasmid and the stable expression of GFP in Listeria ivanovii,bacteria were cultured in the BHI broth with or without erythromycin for several generations. The stability of recombinant plasmid pCW-phly-GFP and fluorescent protein in each generation of bacteriawas studied by extracting plasmids and observing fluorescence. The exactness of recombinant plasmid pCW-phly-GFP was confirmed with restrictive endonuclease assay and sequence analysis. Under the fluorescence microscope,the green fluorescence was obvious in Listeria ivanovii carried with pCW-phly-GFP. The recombinant plasmid pCW-phly-GFP was stable in Listeria ivanovii and the GFP kept expressing in a high level under the pressure of erythromycin. The prokaryotic expression plasmid pCW-phly-GFP containing GFP gene was successfully constructed. Listeria ivanovii carried with the plasmid efficiently expressed GFP. This research provides an important tool for further study of Listeria ivanovii as a vaccine carrier.

  18. Effect of boron waste on the properties of mortar and concrete. (United States)

    Topçu, Iker Bekir; Boga, Ahmet Raif


    Utilization of by-products or waste materials in concrete production are important subjects for sustainable development and industrial ecology concepts. The usages as mineral admixtures or fine aggregates improve the durability properties of concrete and thus increase the economic and environmental advantages for the concrete industry. The effect of clay waste (CW) containing boron on the mechanical properties of concrete was investigated. CW was added in different proportions as cement additive in concrete. The effect of CW on workability and strength of concrete were analysed by fresh and hardened concrete tests. The results obtained were compared with control concrete properties and Turkish standard values. The results showed that the addition of CW had a small effect upon the workability of the concrete but an important effect on the reduction of its strength. It was observed that strength values were quite near to that of control concrete when not more than 10% CW was used in place of cement. In addition to concrete specimens, replacing cement with CW produced mortar specimens, which were investigated for their strength and durability properties. The tests of SO( 4) (2-) and Cl(-) effect as well as freeze-thaw behaviour related to the durability of mortar were performed. Consequently, it can be said that some improvements were obtained in durability properties even if mechanical properties had decreased with increasing CW content.

  19. Chemical and plasma surface modification of lignocellulose coconut waste for the preparation of advanced biobased composite materials. (United States)

    Kocaman, Suheyla; Karaman, Mustafa; Gursoy, Mehmet; Ahmetli, Gulnare


    In this study, surface-modified grinded coconut waste (CW) particles were used as bio-fillers to prepare polymeric composite materials with enhanced properties. Epoxy resin modified with acrylated and epoxidized soybean oil (AESO) was used as the polymer matrix. Two different strategies, namely chemical treatment and plasma enhanced chemical vapor deposition (PECVD) were utilized to modify the surface of CW particles for using them as compatible bio-fillers in composite preparation. Chemical modification involved the treatment of CW particles in a highly alkali NaOH solution, while PECVD modification involved coating of a thin film of hydrophobic poly(hexafluorobutyl acrylate) (PHFBA) around individual CW particle surfaces. Untreated and surface-modified CW particles were used in 10-50wt% for preparation of epoxy composites. FTIR analysis was performed to study the effect of modification on the structures of particles and as-prepared composites. The composite morphologies were investigated by XRD and SE. TGA test was conducted to study the thermal behavior of the composites. Also, the effects of CW particle surface modification on the mechanical and water sorption properties of epoxy resin composites were investigated in detail. It was observed that PECVD-treated CW particles had much more positive effects on the thermal, mechanical, wettability and flammability properties of composites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Corrosive-wear resistance of stainless steels for the impeller of slurry pump used in zinc hydrometallurgy process

    Directory of Open Access Journals (Sweden)

    Ping LI


    Full Text Available This paper presents corrosive-wear (C-W behaviors of three kinds of steels under the simulating condition of traditional zinc hydrometallurgy process by using a self-made rotating disk apparatus. Result shows that pure wear loss rate is significantly larger than pure corrosion loss rate. Under this C-W condition, the ranking of C-W resistance is S2 > S3 > S1 (S1: austenite stainless steel; S2: CD-4MCu duplex stainless steel; S3 :17-4PH stainless steel. S2 has excellent C-W resistance due to strong surface deformation strengthening effect of high-density dislocations of the γ phase. S3 also has excellent C-W resistance owing to high hardness and strength. However, S1 does not show good C-W resistance under strong erosion of liquid-solid slurry because of its single-phase austenitic structure and very low hardness. As a result, duplex stainless steels as well as 17-4 PH stainless steel can be used as impeller candidate materials in the zinc hydrometallurgy process due to their excellent C-W resistance and lower cost.