WorldWideScience

Sample records for ultrasonic ringing pressure

  1. Ultrasonic sludge pretreatment under pressure.

    Science.gov (United States)

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

    2013-09-01

    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Ultrasonic Resonance Spectroscopy of Composite Rings for Flywheel Rotors

    Science.gov (United States)

    Harmon, Laura M.; Baaklini, George Y.

    2001-01-01

    Flywheel energy storage devices comprising multilayered composite rotor systems are being studied extensively for utilization in the International Space Station. These composite material systems were investigated with a recently developed ultrasonic resonance spectroscopy technique. The system employs a swept frequency approach and performs a fast Fourier transform on the frequency spectrum of the response signal. In addition. the system allows for equalization of the frequency spectrum, providing all frequencies with equal amounts of energy to excite higher order resonant harmonics. Interpretation of the second fast Fourier transform, along with equalization of the frequency spectrum, offers greater assurance in acquiring and analyzing the fundamental frequency, or spectrum resonance spacing. The range of frequencies swept in a pitch-catch mode was varied up to 8 MHz, depending on the material and geometry of the component. Single and multilayered material samples, with and without known defects, were evaluated to determine how the constituents of a composite material system affect the resonant frequency. Amplitude and frequency changes in the spectrum and spectrum resonance spacing domains were examined from ultrasonic responses of a flat composite coupon, thin composite rings, and thick composite rings. Also, the ultrasonic spectroscopy responses from areas with an intentional delamination and a foreign material insert, similar to defects that may occur during manufacturing malfunctions, were compared with those from defect-free areas in thin composite rings. A thick composite ring with varying thickness was tested to investigate the full-thickness resonant frequency and any possible bulk interfacial bond issues. Finally, the effect on the frequency response of naturally occurring single and clustered voids in a composite ring was established.

  3. Experimental investigation on sandwich structure ring-type ultrasonic motor.

    Science.gov (United States)

    Peng, Taijiang; Shi, Hongyan; Liang, Xiong; Luo, Feng; Wu, Xiaoyu

    2015-02-01

    This paper presents a manufacture method for a sandwich structure Ultrasonic Motor (USM) and experiment. Two pieces of rotor clamped on a stator, and a stainless steel disk-spring is bonded on the hollow rotor disk to provide the press by a nut assembled on the shaft. The stator is made of a double-side Printed-Circuit Board (PCB) which is sawed out the ring in the center and connected on the board with three legs. On each side of the ring surface, there are electrodes connected at the same position via through hole. The three layer drive circuit for sine, cosine, and ground signal is connected on the board through each leg. There are many piezoelectric components (PZT) bonded between two electrodes and fill soldering tin on each electrode. Then PZT is welded on PCB by reflow soldering. Finally, rub the gibbous soldering tin down to the position of PZT surface makes sure the surface contacts with rotor evenly. The welding process can also be completed by Surface Mounted Technology (SMT). A prototype motor is manufactured by this method. Two B03 model shapes of the stator are obtained by the finite element analysis and the optimal frequency of the motor is 56.375 kHz measured by impedance instrument. The theoretical analysis is conducted for the relationship between the revolving speed of the USM and thickness of stator ring, number of the travelling waves, PZT amplitude, frequency and the other parameters. The experiment result shows that the maximum revolving speed is 116 RPM and the maximum torque is 25 N mm, when the actuate voltage is 200 VAC. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Apparatus for carrying out ultrasonic inspection of pressure vessels

    International Nuclear Information System (INIS)

    Dent, K.H.; Greenhalgh, F.G.

    1975-01-01

    An apparatus is described for moving an ultrasonic scanning mechanism over the interior surface of a pressure vessel and comprising a mast for supporting the scanning mechanism inside the vessel and a carriage for traversing the mast within the vessel, the mast being pivotably secured to the carriage so that when the ultrasonic scanning mechanism contacts the interior surface of the pressure vessel the mast is caused to pivot. (auth)

  5. Piston cylinder cell for high pressure ultrasonic pulse echo measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kepa, M. W., E-mail: mkepa@staffmail.ed.ac.uk; Huxley, A. D. [SUPA, Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom); Ridley, C. J.; Kamenev, K. V. [Centre for Science at Extreme Conditions and School of Engineering, University of Edinburgh, Edinburgh EH9 3FD (United Kingdom)

    2016-08-15

    Ultrasonic techniques such as pulse echo, vibrating reed, or resonant ultrasound spectroscopy are powerful probes not only for studying elasticity but also for investigating electronic and magnetic properties. Here, we report on the design of a high pressure ultrasonic pulse echo apparatus, based on a piston cylinder cell, with a simplified electronic setup that operates with a single coaxial cable and requires sample lengths of mm only. The design allows simultaneous measurements of ultrasonic velocities and attenuation coefficients up to a pressure of 1.5 GPa. We illustrate the performance of the cell by probing the phase diagram of a single crystal of the ferromagnetic superconductor UGe{sub 2}.

  6. Optimization design of high power ultrasonic circular ring radiator in coupled vibration.

    Science.gov (United States)

    Xu, Long; Lin, Shuyu; Hu, Wenxu

    2011-10-01

    This paper presents a new high power ultrasonic (HPU) radiator, which consists of a transducer, an ultrasonic horn, and a metal circular ring. Both the transducer and horn in longitudinal vibrations are used to drive a metal circular ring in a radial-axial coupled vibration. This coupled vibration cannot only generate ultrasound in both the radial and axial directions, but also focus the ultrasound inside the circular ring. Except for the radial-axial coupled vibration mode, the third longitudinal harmonic vibration mode with relative large vibration amplitude is also detected, which can be used as another operation mode. Overall, the HPU with these two vibration modes should have good potential to be applied in liquid processing, such as sonochemistry, ultrasonic cleaning, and Chinese herbal medicine extraction. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Vibrational Characteristics of ring-type ultrasonic motor stator using ESPI

    International Nuclear Information System (INIS)

    Jung, Hyun Kyu; Paik, Sung Hoon; Kim, Seung Ho; Park, Ki Jun; Wang, Young Sung

    2001-01-01

    A stator of ring-type ultrasonic motor composed of the piezoelectric ceramic and the elastic metal was made to generate the travelling wave. Vibrational behavior of the stator was simulated by a finite element analysis using ATILA program and was measured by the electronic speckle pattern interferometry (ESPI) method. The resonance frequencies and vibration modes were analysed depending upon the comparison between the finite element analysis and ESPI measurement. The optimal vibration mode and frequency was estimated to be 7th resonant mode which was corresponded to the measured frequency of 39 KHz. It could be concluded that this fabricated stator can be applied for ring-type ultrasonic motor.

  8. Development of ultrasonic inspection technique for crack detection in retaining rings

    International Nuclear Information System (INIS)

    Brook, M.V.

    1990-01-01

    The majority of retaining rings which are currently in service, are composed of a material which is susceptible to stress corrosion when exposed to moisture. Due to the inherent stress levels in the shrunk-on areas, they are particularly susceptible to stress corrosion attack. Therefore, retaining rings require non-destructive examination to avert catastrophic failure. Guidelines for retaining ring inspection issued by EPRI recommend ultrasonic manual and automated methods of inspection for rings in place. Application of the conventional manual method, using S-waves is difficult, and yields unreliable results. Due to the unreliability factor, utilities have been forced to depend upon surface examination methods, such as visual and penetrant techniques. In most instances, a surface exam will necessitate the costly and potentially damaging removal of the rings from the rotor to provide full access to areas of interest. Due to the various complexities of conventional ultrasonic retaining ring inspections, it is essential that the front end ultrasonics (i.e., transducers and techniques) be optimized to produce the best possible examination. For this reason, AMDATA has developed custom transducers and techniques to enhance automated detection capability of flaws in the various suspect areas of retaining rings. When the optimized techniques are applied to generate the best possible raw data, the Intraspect /98 trademark is then used to reliably apply technique, acquire the data and perform post processing evaluations. One of the most promising ultrasonic techniques for retaining ring inspection is creeping waves. This paper investigates the use of creeping waves for retaining ring inspection

  9. Performance demonstration experience for reactor pressure vessel shell ultrasonic testing

    International Nuclear Information System (INIS)

    Zado, V.

    1998-01-01

    The most ultrasonic testing techniques used by many vendors for pressurized water reactor (PWR) examinations were based on American Society of Mechanical Engineers 'Boiler and Pressurized Vessel Code' (ASME B and PV Code) Sections XI and V. The Addenda of ASME B and PV Code Section XI, Edition 1989 introduced Appendix VIII - 'Performance Demonstration for Ultrasonic Examination Systems'. In an effort to increase confidence in performance of ultrasonic testing of the operating nuclear power plants in United States, the ultrasonic testing performance demonstration examination of reactor vessel welds is performed in accordance with Performance Demonstration Initiative (PDI) program which is based on ASME Code Section XI, Appendix VIII requirements. This article provides information regarding extensive qualification preparation works performed prior EPRI guided performance demonstration exam of reactor vessel shell welds accomplished in January 1997 for the scope of Appendix VIII, Supplements IV and VI. Additionally, an overview of the procedures based on requirements of ASME Code Section XI and V in comparison to procedure prepared for Appendix VIII examination is given and discussed. The samples of ultrasonic signals obtained from artificial flaws implanted in vessel material are presented and results of ultrasonic testing are compared to actual flaw sizes. (author)

  10. High pressure photoinduced ring opening of benzene

    International Nuclear Information System (INIS)

    Ciabini, Lucia; Santoro, Mario; Bini, Roberto; Schettino, Vincenzo

    2002-01-01

    The chemical transformation of crystalline benzene into an amorphous solid (a-C:H) was induced at high pressure by employing laser light of suitable wavelengths. The reaction was forced to occur at 16 GPa, well below the pressure value (23 GPa) where the reaction normally occurs. Different laser sources were used to tune the pumping wavelength into the red wing of the first excited singlet state S 1 ( 1 B 2u ) absorption edge. Here the benzene ring is distorted, presenting a greater flexibility which makes the molecule unstable at high pressure. The selective pumping of the S 1 level, in addition to structural considerations, was of paramount importance to clarify the mechanism of the reaction

  11. Apparatus for carrying out ultrasonic inspection of pressure vessels

    International Nuclear Information System (INIS)

    Dent, K.H.; Challender, R.S.

    1975-01-01

    A carriage-supported manipulator for taking an ultrasonic scanner mechanism into a coolant nozzle of a nuclear reactor pressure vessel is described. The manupulator is rotatable about the axis of the nozzle and is radially expansible to urge the scanner mechanism into a scanning position within the nozzle

  12. In-service ultrasonic inspection of nuclear reactor pressure vessels

    International Nuclear Information System (INIS)

    Prepechal, J.; Sulc, J.

    1982-01-01

    Ultrasonic tests of pressure vessels for WWER 440 reactors, type 213 V, are carried out partly manually and partly by test equipment. The inner surface of the pressure vessel is tested using device REACTORTEST TRC which is fully mobile. The outer surface of the cylindrical parts and bottoms of the body is tested using handling equipment permanently in-built under the pressure vessel and dismountable testing heads. A set of these heads may be used for two reactor units. The testing equipment REACTORTEST TRC is equipped with a TRC 800 ultrasound device. The equipment for testing the outer surface of the vessel operates with the UDAR 16 ultrasound apparatus to which may be simultaneously connected 10 ultrasound probes and six probes for acoustic feedback. The whole system of ultrasonic tests makes possible a first-rate and reliable volume control of the whole pressure vessel and all points where cracks may originate and grow. (Z.M.)

  13. Automated ultrasonic shop inspection of reactor pressure vessel forgings

    International Nuclear Information System (INIS)

    Farley, J.M.; Dikstra, B.J.; Hanstock, D.J.; Pople, C.H.

    1986-01-01

    Automated ultrasonic shop inspection utilizing a computer-controlled system is being applied to each of the forgings for the reactor pressure vessel of the proposed Sizewell B PWR power station. Procedures which utilize a combination of high sensitivity shear wave pulse echo, 0 degrees and 70 degrees angled longitudinal waves, tandem and through-thickness arrays have been developed to provide comprehensive coverage and an overall reliability of inspection comparable to the best achieved in UKAEA defect detection trials and in PISC II. This paper describes the ultrasonic techniques, the automated system (its design, commissioning and testing), validation and the progress of the inspections

  14. An application of ultrasonic inspection system (INER-SCAN) inspecting generator retaining rings

    International Nuclear Information System (INIS)

    Chen, L.C.; Hwang, S.C.

    1994-01-01

    The performances of the automatic ultrasonic inspecting and imaging system (INER-SCAN) developed by the NDT laboratory of the Institute of Nuclear Energy Research have been enhanced and much more improved to commercial level. With appropriate rearrangements of software libraries, it is used to inspect generator retaining rings which are critical structural rotor components that support the end-turn regions of the rotor wingings against centrifugal forces. The use of the INER-SCAN provides distinct advantages over other systems in terms of the reliability of inspection and the flexibility of system performance modifications. The INER-SCAN system assists users to select and modify ultrasonic parameters under computer-aided environment. In addition, the INER-SCAN system contains the necessary software functions to image the ultrasonic data (A-SCAN, B-SCAN, B'-SCAN, C-SCAN). The use of the imaging system makes it quite easy to evaluate various test parameters and their effects on the discrimination between geometric and IGSCC reflectors. Through experimental test, it is recognized that the system has powerful detectable capability which can find 0.2mm-depth slight scratch on the inner surface of retaining rings. This system can also be used on different generator retaining rings (different in terms of hidden design features) without the need for access to the dimension of retaining ring

  15. New developments in ultrasonic inspection of retaining rings on generators in operation

    International Nuclear Information System (INIS)

    Koch-Mathian, A.

    1990-01-01

    The ultrasonic inspection of retaining rings of operating generators has been operational since 1986. The aim of this presentation is to outline the experience acquired on many retaining rings on different types of generators. In-situ inspections have made it possible to detect more exactly the different shape echoes for the various elements located beneath the retaining ring such as rotor teeth, damping and epoxy insulation. Various methods of identifying these parts are currently being developed. Investigation on corroded retaining rings has made it possible to demonstrate the close correlation between the transverse beam detection and the presence of actual cracks identified by micrograph. The specific facies of these cracks precludes the use of classic dimensioning techniques, but a method based on longitudinal wave detection has already given encouraging results

  16. Apparatus for carrying out ultrasonic inspection of pressure vessels

    International Nuclear Information System (INIS)

    Dent, K.H.; Challender, R.S.

    1975-01-01

    Apparatus is described for use in carrying out ultrasonic inspection of coolant nozzles of nuclear reactor pressure vessels. It comprises a manipulator for supporting an ultrasonic scanning transducer within the coolant nozzle. The manipulator is carried by a support located within the pressure vessel and comprises a pair of legs pivotable in caliper manner to span the base of the nozzle. Means are provided for pivoting the legs together to enable free entry of the manipulator and scanning transducer into the nozzle, and for pivoting the legs apart to bring the transducer into an operating position adjacent to the wall of the nozzle. The manipulator is rotatable within the nozzle to enable scanning of its interior surface. (U.K.)

  17. Ultrasonic testing of electron beam closure weld on pressure vessel

    International Nuclear Information System (INIS)

    Andrews, R.W.

    1975-01-01

    One of the special products manufactured at the General Electric Neutron Devices Department (GEND) is a small stainless steel vessel designed to hold a component under high pressure for long periods. The vessel is a thick-walled cylinder with a threaded receptacle into which a plug is screwed and welded after receiving the unit to be tested. The test cavity is then pressurized through a small diameter opening in the bottom and that opening is welded closed. When x-ray inspection techniques did not reveal defective welds at the threaded plug in a pressured vessel, occasional ''leakers'' occurred. With normal equipment tolerances, the electron beam spike tends to wander from the desired path, particularly at the root of the weld. Ultrasonic techniques were used to successfully inspect the weld. The testing technique is based on the observation that ultrasonic energy is reflected from the unwelded screw threads and not from the regions where the threads are completely fused together by welding. Any gas pore or any threaded region outside the weld bead can produce an echo. The units are rotated while the ultrasonic transducer travels in a direction parallel to the axis of rotation and toward the welded end. This produces a helical scan which is converted to a two-dimensional presentation in which incomplete welds can be noted. (U.S.)

  18. Ultrasonic level sensors for liquids under high pressure

    Science.gov (United States)

    Zuckerwar, A. J.; Mazel, D. S.; Hodges, D. Y.

    1986-01-01

    An ultrasonic level sensor of novel design continuously measures the level of a liquid subjected to a high pressure (up to about 40 MPa), as is sometimes required for the effective transfer of the liquid. The sensor operates as a composite resonator fabricated from a standard high-pressure plug. A flat-bottom hole is machined into the plug along its center line. An ultrasonic transducer is bonded rigidly to the interior surface of the bottom wall, while the exterior surface is in contact with the liquid. Although the bottom wall is designed to satisfy the pressure code, it is still sufficiently thin to permit ready excitation of the axisymmetric plate modes of vibration. The liquid level is measured by a conventional pulse-echo technique. A prototype sensor was tested successfully in a 2300-l water vessel at pressures up to about 37 MPa. A spectral analysis of the transmitted pulse reveals that the flexural, extensional, thickness-shear, and radial plate modes are excited into vibration, but none of these appears to be significantly affected by the pressurization of the liquid.

  19. Italian developments in the ultrasonic examination of pressure vessels

    International Nuclear Information System (INIS)

    Regis, V.

    1987-01-01

    A review of developments being pursued in Italy in ultrasonics for application to pressure vessels is presented. Although nuclear construction in Italy has suffered heavy delays, R and D activities promoted by the Italian Electricity Board in the mid 1970s on advanced UT for non-destructive inspection of thick welded sections made it possible to obtain significant results scored by CISE Laboratories, mainly through the design, construction and qualification of the manual UT spectroscopy and signal processing computerized ARICE system and of the mechanized multifrequency acoustic holography HADIS system. Meanwhile theoretical ultrasonic modelling is actively studied in order to implement software applications and the overall reliability of UT inspections with regard to flaw detection, location and sizing. Selected contributions from manufacturers and service companies with a view to improving UT practice are acknowledged, and still wider technology transfers may be expected in the future, also under ENEA industrial promotion programmes. (author)

  20. Pre and post garter spring repositioning ultrasonic inspection of pressure tubes

    International Nuclear Information System (INIS)

    Desimone, C.; Katchadjian, P.; Tacchia, Mauricio

    1997-01-01

    This paper present a description of the ultrasonic cracked hydride blister detections system used for pre and post inspection of pressure tubes during garter spring repositioning in CNE (Embalse Nuclear Power Station). Ultrasonic system setup configuration, transducers characteristics, blister detection head, calibration of parameters, operating procedure, records of ultrasonic inspections and evaluation. (author) [es

  1. Pressure bump instability in very large cold bore storage rings

    International Nuclear Information System (INIS)

    Limon, P.

    1983-12-01

    Calculations have been done to estimate the circulating current necessary to induce the onset of a pressure bump instability in a cold bore storage ring. For a wide range of storage ring parameters, the instability threshold current is more than an order of magnitude higher than the operating current. 4 references, 2 tables

  2. Osmotic pressure of ring polymer solutions : A Monte Carlo study

    NARCIS (Netherlands)

    Flikkema, Edwin; Brinke, Gerrit ten

    2000-01-01

    Using the wall theorem, the osmotic pressure of ring polymers in solution has been determined using an off-lattice topology conserving Monte Carlo algorithm. The ring polymers are modeled as freely-jointed chains with point-like beads, i.e., under conditions corresponding to θ-conditions for the

  3. Development of automatic ultrasonic testing equipment for reactor pressure vessel

    International Nuclear Information System (INIS)

    Jang, Kee Ok; Park, Dae Yung; Park, Moon Hoh; Koo, Kil Mo; Park, Kwang Heui; Kang, Sang Sin; Bang, Heui Song; Noh, Heui Choong; Kong, Woon Sik

    1994-08-01

    The selected weld areas of reactor pressure vessel and adjacent piping are examined by remote mechanized ultrasonic testing(MUT) equipment. Since the MUT equipment was purchased from Southwest Research Institute (SwRI) in April 1985, we have performed 15 inservice inspections and 5 preservice inspections. However, the reliability of examination was recently decreased rapidly as the problems which results from the old age of equipment and the frequent movement to plant site to site have occurred frequently. Therefore, the 3-axis control system hardware in occurring many problems among the equipments of mechanized ultrasonic testing (MUT) was designed and developed to cover the examination areas of nozzle-shell weld as specified in ASME Code Section XI and to improve the examination reliability. The new 3-axis control system hardware with the performance of this project was developed to be compatible with the old one and it was used as dual system or spare parts of the old system. Furthermore, the established technologies are expected to be applied to the similar control systems in nuclear power plant. 17 figs, 2 pix, 2 tabs, 10 refs. (Author)

  4. Development of automatic ultrasonic testing equipment for reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kee Ok; Park, Dae Yung; Park, Moon Hoh; Koo, Kil Mo; Park, Kwang Heui; Kang, Sang Sin; Bang, Heui Song; Noh, Heui Choong; Kong, Woon Sik [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-08-01

    The selected weld areas of reactor pressure vessel and adjacent piping are examined by remote mechanized ultrasonic testing(MUT) equipment. Since the MUT equipment was purchased from Southwest Research Institute (SwRI) in April 1985, we have performed 15 inservice inspections and 5 preservice inspections. However, the reliability of examination was recently decreased rapidly as the problems which results from the old age of equipment and the frequent movement to plant site to site have occurred frequently. Therefore, the 3-axis control system hardware in occurring many problems among the equipments of mechanized ultrasonic testing (MUT) was designed and developed to cover the examination areas of nozzle-shell weld as specified in ASME Code Section XI and to improve the examination reliability. The new 3-axis control system hardware with the performance of this project was developed to be compatible with the old one and it was used as dual system or spare parts of the old system. Furthermore, the established technologies are expected to be applied to the similar control systems in nuclear power plant. 17 figs, 2 pix, 2 tabs, 10 refs. (Author).

  5. Isometric multimodal photoacoustic microscopy based on optically transparent micro-ring ultrasonic detection.

    Science.gov (United States)

    Dong, Biqin; Li, Hao; Zhang, Zhen; Zhang, Kevin; Chen, Siyu; Sun, Cheng; Zhang, Hao F

    2015-01-01

    Photoacoustic microscopy (PAM) is an attractive imaging tool complementary to established optical microscopic modalities by providing additional molecular specificities through imaging optical absorption contrast. While the development of optical resolution photoacoustic microscopy (ORPAM) offers high lateral resolution, the acoustically-determined axial resolution is limited due to the constraint in ultrasonic detection bandwidth. ORPAM with isometric spatial resolution along both axial and lateral direction is yet to be developed. Although recently developed sophisticated optical illumination and reconstruction methods offer improved axial resolution in ORPAM, the image acquisition procedures are rather complicated, limiting their capabilities for high-speed imaging and being easily integrated with established optical microscopic modalities. Here we report an isometric ORPAM based on an optically transparent micro-ring resonator ultrasonic detector and a commercial inverted microscope platform. Owing to the superior spatial resolution and the ease of integrating our ORPAM with established microscopic modalities, single cell imaging with extrinsic fluorescence staining, intrinsic autofluorescence, and optical absorption can be achieved simultaneously. This technique holds promise to greatly improve the accessibility of PAM to the broader biomedical researchers.

  6. A new traveling wave ultrasonic motor using thick ring stator with nested PZT excitation.

    Science.gov (United States)

    Chen, Weishan; Shi, Shengjun; Liu, Yingxiang; Li, Pei

    2010-05-01

    To avoid the disadvantages of conventional traveling wave ultrasonic motors--lower efficiency PZT working mode of d(31), fragility of the PZT element under strong excitation, fatigue of the adhesive layer under harsh environmental conditions, and low volume of the PZT material in the stator--a new type of traveling wave ultrasonic motor is presented in this paper. Here we implement the stator by nesting 64 PZT stacks in 64 slots specifically cut in a thick metal ring and 64 block springs nested within another 64 slots to produce preloading on the PZT stacks. In this new design, the d33 mode of the PZT is used to excite the flexural vibrations of the stator, and fragility of the PZT ceramics and fatigue of the adhesive layer are no longer an issue. The working principle, FEM simulation, fabrication, and performance measurements of a prototype motor were demonstrated to validate the proposed ideas. Typical output of the prototype motor is no-load speed of 15 rpm and maximum torque of 7.96 N x m. Further improvement will potentially enhance its features by increasing the accuracy in fabrication and adopting appropriate frictional material into the interface between the stator and the rotor.

  7. Neutron and ultrasonic determination of residual stress in an aluminum ring-plug

    International Nuclear Information System (INIS)

    Prask, H.J.; Gnaeupel-Herold, T.; Clark, A.V.; Hehman, C.S.; Nguyen, T.N.

    2000-01-01

    Stress is a principal cause of material failure. This has been a well-recognized problem for decades, yet--in general--neutron diffraction remains the only way to measure sub-surface residual stresses without destroying the component. A field-portable ultrasonic strain-meter is being developed at NIST (Boulder) to determine residual stresses in engineering specimens, nondestructively. To test this and other techniques an array of stress-measurement standards are being prepared. These will be characterized by neutron diffraction and then used to evaluate, quantitatively, the potential of new methods. The first standard specimen produced for this purpose is a large shrink-fit ring-plug of 2024 aluminum (305 mm OD, 25.4 mm thick, 101.6 mm diameter plug). Because of large grain size, a sample-rotation averaging technique was developed to make reliable neutron measurements possible. A comparison of the neutron diffraction and ultrasonic results for this specimen will be presented, along with strain gauge results

  8. Connecting ring and process to fix heaters in a pressure vessel by means of these rings

    International Nuclear Information System (INIS)

    Bailleul, G.; Caloine, P.; Coville, P.

    1984-01-01

    The invention can applies to the installation of heaters for nuclear reactor pressurizer or to the installation of any kind of reheaters by means of electric resistances when these reheaters have to work under important pressures. The connecting ring is made of a single metallic piece, two coaxial tubes joined each other by a skirt nearly radial; the skirt joins an end of the outer cylindrical tube and an intermediate zone of the inner cylindrical tube. The invention concerns also a heater provided with such a connecting ring, substituted for a part of its metallic envelope, and a process of fastening of these heaters on a pressure vessel. The description given in the frame of a pressurizer applies to the case of a gas reheater or to a reheater for liquid under pressure such as liquid sodium in a tank [fr

  9. 50-Hz plasma treatment of glass fibre reinforced polyester at atmospheric pressure enhanced by ultrasonic irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Norrman, Kion; Singh, Shailendra Vikram

    2011-01-01

    Glass fibre reinforced polyester (GFRP) plates are treated using a 50-Hz dielectric barrier discharge at peak-to-peak voltage of 30 kV in helium at atmospheric pressure with and without ultrasonic irradiation to study adhesion improvement. The ultrasonic waves at the fundamental frequency of around...

  10. INVESTIGATION OF MATERIAL RESISTANCE TO PLASTIC DEFORMATION AT PROCESSING METALS BY PRESSURE WITH IMPOSING ULTRASONIC OSCILLATIONS

    Directory of Open Access Journals (Sweden)

    V. V. Klubovich

    2007-01-01

    Full Text Available The paper contains substantiation for application of experimental technique in order to investigate material resistance to plastic deformation at processing metals by pressure with imposing ultrasonic oscillations while proceeding from laws of similarity. It is shown that at modeling any metal processing by pressure with imposing ultrasonic oscillations it is possible to consider that actual elastic and plastic metal properties remain constant during processing under ultrasound action. The second aspect that requires a special attention at modeling is pulse or vibration-shock deformation at processing metals by pressure with imposing ultrasonic oscillations.

  11. Improvement of remote control system of automatic ultrasonic equipment for inspection of reactor pressure vessel

    International Nuclear Information System (INIS)

    Cheong, Yong Moo; Jung, H. K.; Joo, Y. S.; Koo, K. M.; Hyung, H.; Sim, C. M.; Gong, U. S.; Kim, S. H.; Lee, J. P.; Rhoo, H. C.; Kim, M. S.; Ryoo, S. K.; Choi, C. H.; Oh, K. I.

    1999-12-01

    One of the important issues related to the nuclear safety is in-service inspection of reactor pressure vessel (RPV). A remote controlled automatic ultrasonic method is applied to the inspection. At present the automatic ultrasonic inspection system owned by KAERI is interrupted due to degradation of parts. In order to resume field inspection new remote control system for the equipment was designed and installed to the existing equipment. New ultrasonic sensors and their modules for RPV inspection were designed and fabricated in accordance with the new requirements of the inspection codes. Ultrasonic sensors were verified for the use in the RPV inspection. (author)

  12. Improvement of remote control system of automatic ultrasonic equipment for inspection of reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Yong Moo; Jung, H. K.; Joo, Y. S.; Koo, K. M.; Hyung, H.; Sim, C. M.; Gong, U. S.; Kim, S. H.; Lee, J. P.; Rhoo, H. C.; Kim, M. S.; Ryoo, S. K.; Choi, C. H.; Oh, K. I

    1999-12-01

    One of the important issues related to the nuclear safety is in-service inspection of reactor pressure vessel (RPV). A remote controlled automatic ultrasonic method is applied to the inspection. At present the automatic ultrasonic inspection system owned by KAERI is interrupted due to degradation of parts. In order to resume field inspection new remote control system for the equipment was designed and installed to the existing equipment. New ultrasonic sensors and their modules for RPV inspection were designed and fabricated in accordance with the new requirements of the inspection codes. Ultrasonic sensors were verified for the use in the RPV inspection. (autho0008.

  13. Characterization and optimization of an ultrasonic piezo-optical ring sensor

    International Nuclear Information System (INIS)

    Frankforter, Erik; Lin, Bin; Giurgiutiu, Victor

    2016-01-01

    A resonant piezo-optical ring sensor with both piezoelectric and fiber Bragg grating (FBG) sensing elements was assessed for ultrasonic wave detection. The ring sensor is an existing device that has been shown experimentally to exhibit a number of sensing features: omnidirectionality, mode selectivity, and frequency tunability. The present study uses finite element modeling to understand these features as a means to characterize and optimize the sensor. A combined vibration-wave propagation modeling approach was used, where the vibrational modeling provided a basis for understanding sensing features, and the wave propagation modeling provided predictive power for sensor performance. The sensor features corresponded to the fundamental vibrational mode of the sensor, particularly to the base motion of this mode. The vibrational modeling was also used to guide sensor optimization, with an emphasis on the FBG and piezoelectric sensing elements. It was found that sensor symmetry and nodes of extraneous resonance modes could be exploited to provide a single-resonance response. A series of pitch-catch guided wave experiments were performed on a thin aluminum plate to assess the optimized sensor configuration. Tuning curves showed a single-frequency response to a Lamb wave and mechanical filtering away from the dominant frequency; the sensor capability for mechanical amplification of a Lamb wave and mechanical amplification of a pencil-lead-break acoustic emission event were also demonstrated. (paper)

  14. More recent developments for the ultrasonic testing of light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Seiger, H.; Engl, G.

    1976-01-01

    The development of an ultrasonic testing method for the inspection from the outside of the areas close to the cladding of the spherical fields of holes of light water reactor pressure vessels is described

  15. Development of automatic Ultrasonic testing equipment for reactor pressure vessel

    International Nuclear Information System (INIS)

    Kim, Kor R.; Kim, Jae H.; Lee, Jae C.

    1996-06-01

    The selected weld areas of a reactor pressure vessel and adjacent piping are examined by the remote mechanized ultrasonic testing (MUT) equipment. Since the MUT equipment was purchased from southwest Research Institute (SwRI) in April 1985, 15 inservice inspections and 5 preservice inspections are performed with this MUT equipment. However due to the old age of the equipment and frequent movements to plant sites, the reliability of examination was recently decreased rapidly and it is very difficult to keep spare parts. In order to resolve these problems and to meet the strong request from plant sites, we intend to develop a new 3-axis control system including hardware and software. With this control system, we expect more efficient and reliable examination of the nozzle to shell weld areas, which is specified in ASME Code Section XI. The new 3-axis control system hardware and software were designed and development of our own control system, the advanced technologies of computer control mechanism were established and examination reliability of the nozzle to shell weld area was improved. With the development of our 3-axis control system for PaR ISI-2 computer control system, the reliability of nozzle to shell weld area examination has been improved. The established technologies from the development and detailed analysis of existing control system, are expected to be applied to the similar control systems in nuclear power plants. (author). 12 refs., 4 tabs., 33 figs

  16. Development of automatic Ultrasonic testing equipment for reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kor R.; Kim, Jae H.; Lee, Jae C.

    1996-06-01

    The selected weld areas of a reactor pressure vessel and adjacent piping are examined by the remote mechanized ultrasonic testing (MUT) equipment. Since the MUT equipment was purchased from southwest Research Institute (SwRI) in April 1985, 15 inservice inspections and 5 preservice inspections are performed with this MUT equipment. However due to the old age of the equipment and frequent movements to plant sites, the reliability of examination was recently decreased rapidly and it is very difficult to keep spare parts. In order to resolve these problems and to meet the strong request from plant sites, we intend to develop a new 3-axis control system including hardware and software. With this control system, we expect more efficient and reliable examination of the nozzle to shell weld areas, which is specified in ASME Code Section XI. The new 3-axis control system hardware and software were designed and development of our own control system, the advanced technologies of computer control mechanism were established and examination reliability of the nozzle to shell weld area was improved. With the development of our 3-axis control system for PaR ISI-2 computer control system, the reliability of nozzle to shell weld area examination has been improved. The established technologies from the development and detailed analysis of existing control system, are expected to be applied to the similar control systems in nuclear power plants. (author). 12 refs., 4 tabs., 33 figs.

  17. Atmospheric pressure microwave plasma system with ring waveguide

    International Nuclear Information System (INIS)

    Liu Liang; Zhang Guixin; Zhu Zhijie; Luo Chengmu

    2007-01-01

    Some scientists used waveguide as the cavity to produce a plasma jet, while large volume microwave plasma was relatively hard to get in atmospheric pressure. However, a few research institutes have already developed devices to generate large volume of atmospheric pressure microwave plasma, such as CYRANNUS and SLAN series, which can be widely applied. In this paper, present a microwave plasma system with ring waveguide to excite large volume of atmospheric pressure microwave plasma, plot curves on theoretical disruption electric field of some working gases, emulate the cavity through software, measure the power density to validate and show the appearance of microwave plasma. At present, large volume of argon and helium plasma have already been generated steadily by atmospheric pressure microwave plasma system. This research can build a theoretical basis of microwave plasma excitation under atmospheric pressure and will be useful in study of the device. (authors)

  18. Influence of gas law on ultrasonic behaviour of porous media under pressure.

    Science.gov (United States)

    Griffiths, S; Ayrault, C

    2010-06-01

    This paper deals with the influence of gas law on ultrasonic behaviour of porous media when the saturating fluid is high pressured. Previous works have demonstrated that ultrasonic transmission through a porous sample with variations of the static pressure (up to 18 bars) of the saturating fluid allows the characterization of high damping materials. In these studies, the perfect gas law was used to link static pressure and density, which is disputable for high pressures. This paper compares the effects of real and perfect gas laws on modeled transmission coefficient for porous foams at these pressures. Direct simulations and a mechanical parameters estimation from minimization show that results are very similar in both cases. The real gas law is thus not necessary to describe the acoustic behaviour of porous media at low ultrasonic frequencies (100 kHz) up to 20 bars. 2010 Elsevier B.V. All rights reserved.

  19. Ultrasonic stress evaluation through thickness of a stainless steel pressure vessel

    International Nuclear Information System (INIS)

    Javadi, Yashar; Pirzaman, Hamed Salimi; Raeisi, Mohammadreza Hadizadeh; Najafabadi, Mehdi Ahmadi

    2014-01-01

    This paper investigates ultrasonic method in stress measurement through thickness of a pressure vessel. Longitudinal critically refracted (L CR ) waves are employed to measure the welding residual stresses in a vessel constructed from austenitic stainless steel 304L. The acoustoelastic constant is measured through a hydro test to keep the pressure vessel intact. Hoop and axial residual stresses are evaluated by using different frequency range of ultrasonic transducers. The welding processes of vessel shell and caps are simulated by a 3D finite element (FE) model which is validated by hole-drilling method. The residual stresses calculated by FE simulation are then compared with those obtained from the ultrasonic measurement while a good agreement is observed. It is demonstrated that the residual stresses through thickness of the stainless steel pressure vessel can be evaluated by combining FE and L CR method (known as FEL CR method). - Highlights: • The main goal is ultrasonic evaluation of through thickness stresses. • Welding processes of a stainless steel pressure vessel are modelled by FE. • The hole-drilling method is used to validate the FE results. • Residual stresses are measured by four different series of ultrasonic transducers. • The comparison between ultrasonic and FE results show an acceptable agreement

  20. Device for positioning ultrasonic probes and/or television cameras on the outer surface of reactor pressure vessels

    International Nuclear Information System (INIS)

    Zipser, R.; Dose, G.F.

    1977-01-01

    The device makes possible periodical in-service inspections of welding seams and material of a reactor pressure vessel without local human presence. A 'support ring' encloses the pressure vessel in a horizontal plane with free space. It is vertically moved up and down in the space between pressure vessel and thermal shield by means of tackles. At a control desk placed in a protected area its movement is controlled and its vertical position is indicated. A 'rotating track' with its own drive is rotating remote-controlled on the 'support ring'. By a combination of the vertical with the rotating movement, an ultrasonic probe placed removably on the 'rotating hack', or a television camera will be brought to any position on the cylindrical circumference of the pressure vessel. Special devices extend the radius of action, in upward direction for inspecting the welding seams of the coolant nozzles, and in downward direction for the inspection of welds on the hemispherical bottom of the pressure vessel or on the outlet pipe nozzle placed there. The device remains installed during reactor operation, but is moved down to the lower horizontal surface of the thermal shield. Parts which are sensible to radiation like probes or television cameras and special devices will then be removed respectively mounted before beginning an inspection compaign. This position may be reached by the lower access in the biological shield and through an opening in the horizontal surface of the thermal shield. (HP) [de

  1. Joint formation of dissimilar steels in pressure welding with superposition of ultrasonic oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Surovtsev, A P; Golovanenko, S A; Sukhanov, V E; Kazantsev, V F

    1983-12-01

    Investigation results of kinetics and quality of carbon steel joints with the steel 12Kh18N10T, obtained by pressure welding with superposition of ultrasonic oscillations with the frequency 16.5-18.0 kHz are given. The effect of ultrasonic oscillations on the process of physical contact development of the surfaces welded, formation of microstructure and impact viscosity of the compound, is shown.

  2. Employment of a novel ultrasonic method to investigate high pressure phase transitions in oleic acid

    Science.gov (United States)

    Rostocki, A. J.; Siegoczyński, R. M.; Kiełczyński, P.; Szalewski, M.; Balcerzak, A.; Zduniak, M.

    2011-06-01

    In this work, the variation of sound velocity with hydrostatic pressure for oleic acid is evaluated up to 350 MPa. During the measurement, we identified the phase transformation of oleic acid and the presence of the hysteresis of the dependence of sound velocity on pressure. From the performed measurements, it can be seen that the dependence of sound velocity on pressure can be used to investigate phase transformations in natural oils. Ultrasonic waves were excited and detected using piezoelectric LiNbO3(Y-36 cut) 5 MHz transducers. The phase velocity of the longitudinal ultrasonic waves was measured using a cross-correlation method to evaluate the time of flight.

  3. High pressure changes of the castor oil viscosity by ultrasonic method

    International Nuclear Information System (INIS)

    Rostocki, A J; Siegoczynski, R M; Kielczynski, P; Szalewski, M

    2008-01-01

    The pressure change of viscosity of castor oil have been measured by ultrasonic method within the range of pressure up to 0.9 GPa. For the measurement, the authors have applied a new ultrasonic method based on Bleustein-Gulyaev (B-G) waves. For the lower pressures (up to 0.3 GPa) the results have been compared with earlier results obtained by falling body method, whereas for the higher pressure range results were compared with those obtained by the flow type viscometer. The measurements have shown: 1. Exponential rise of viscosity with pressure up to 0.4 GPa according to the Barus formula. 2. Extraordinary increment of viscosity at constant pressure during phase transition. 3. The decomposition of the high pressure phase during the decompression process have shown very large hysteresis of viscosity on pressure. 4. After the decompression process the viscosity lasts higher then a initial value for several hours

  4. Determination of gas pressure in voids in epoxy casting using an ultrasonic measuring technique

    DEFF Research Database (Denmark)

    Larsen, Esben; Petersen, C. Bak; Henriksen, Mogens

    1990-01-01

    Results of measurements performed on a large open void, where pressure can be controlled from the outside, are compared to the theory of ultrasound transmission. The results verify the theory that the attenuation of transmitted ultrasonic signals through a void depends on the gas pressure inside ...

  5. The PISC exercise: a discussion of its relevance to ultrasonic inspection of pressure vessels

    International Nuclear Information System (INIS)

    Whittle, M.J.; Coffey, J.M.

    1981-01-01

    The value of the European Plate Inspection Steering Committee (PISC) exercise for determining the reliability of ultrasonic inspection of pressure vessels is discussed. It is argued that the particular ultrasonic procedure assessed in the exercise was a poor one whose failure was predictable. In addition the test blocks were sufficiently unrealistic that the value of the results would have been diminished even if all the defects had been found. Consequently the report maintains that the outcome of the exercise is largely irrelevant to the wider question of the reliability of more thorough ultrasonic procedures. A more general discussion is given of the role of test block studies in ultrasonics. Statistical arguments are used to show that it is impracticable to produce a sufficient number of defects to demonstrate a high reliability and have a high confidence in such a result. Some important points for planning future programmes are emphasised. (author)

  6. The Ontario hydro low pressure turbine disc inspection program automated ultrasonic inspection systems - an overview

    International Nuclear Information System (INIS)

    Huggins, J.W.; Chopcian, M.; Grabish, M.

    1990-01-01

    An overview of the Ontario Hydro Low Pressure Turbine Disc Inspection Program is presented. The ultrasonic inspection systems developed in-house to inspect low pressure turbine discs at Pickering and Bruce Nuclear Generating stations are described. Three aspects of the program are covered: PART I - Background to inspection program, disc cracking experience, and development of an in-house inspection capability: PART II - System development requirements; ultrasonic equipment, electromechanical subsystems and instrumentation console: PART III - Customized software for flaw detection, sizing, data acquisition/storage, advanced signal processing, reports, documentation and software based diagnostics

  7. Remote controlled ultrasonic pre-service and in-service inspections of reactor pressure vessels

    International Nuclear Information System (INIS)

    Mueller, G.

    1990-01-01

    The first mechanised in-service inspection of the reactor pressure vessel on unit one of Eskom's Koeberg nuclear power station has been carried out. Since 1968 a whole range of manipulators to carry out remote controlled ultrasonic inspections of nuclear power station equipment has been developed. The inspection of a reactor pressure vessel using a central mast manipulator is described. 3 figs., 1 ill

  8. Babcock experience of automated ultrasonic non-destructive testing of PWR pressure vessels during manufacture

    International Nuclear Information System (INIS)

    Dikstra, B.J.; Farley, J.M.; Scruton, G.

    1990-01-01

    Major developments in ultrasonic techniques, equipment and systems for automated inspection have lead, over a period of about ten years, to the regular application of sophisticated computer-controlled systems during the manufacture of nuclear reactor pressure vessels. Ten years ago the use of procedures defined in a code such as ASME XI might have been considered sufficient, but it is now necessary, as was demonstrated by the results of the UKAEA defect detection trials and the PISC II trials, to apply more comprehensive arrays of probes and higher test sensitivities. The ultrasonic techniques selected are demonstrated to be adequate by modelling or test-block exercises, the automated systems applied are subject to stringent quality assurance testing, and very rigorous inspection procedures are used in conjunction with a high degree of automation to ensure reproducibility of inspection quality. The state-of-the-art in automated ultrasonic testing of pressure vessels by Babcock is described. Current developments by the company, including automated flaw recognition, integrated modelling of inspection capability, and the use of electronically scanned variable-angle probes are reviewed. Examples quoted include the automated ultrasonic inspections of the Sizewell B pressurized water reactor vessel. (author)

  9. Validated automated ultrasonic inspections of the Sizewell 'B' reactor pressure vessel

    International Nuclear Information System (INIS)

    Dikstra, B.J.; Farley, J.M.

    1992-01-01

    Automated ultrasonic inspection was applied extensively during manufacture of the RPV for Sizewell 'B'. This was an important element of the safety case presented at the Sizewell 'B' public enquiry. This requirement reflected concern in the United Kingdom as to the effectiveness and reliability of ultrasonic inspections. By applying automated inspections in addition to the manual ultrasonic inspection carried out by the vessel manufacturer, the overall reliability of the inspection of the vessel would be considerably enhanced. The automated inspections carried out in the manufacturer's workshops were termed 'automated shop inspections' (ASIs). The ASIs were carried out in two contracts: the first to inspect the component forgings of the RPV, the second to inspect the pressure retaining welds. (author)

  10. Pressure-mediated reduction of ultrasonically induced cell lysis

    International Nuclear Information System (INIS)

    Ciaravino, V.E.; Miller, M.W.; Carstensen, E.L.

    1981-01-01

    Chinese hamster V-79 cells, exposed in polystyrene tubes for 5 min to 1-MHz continuous-wave ultrasound, were lysed more by a 10 than a 5 W/cm 2 intensity. Higher atmospheric pressure was needed to eliminate lysis with the former relative to the latter intensity, but lysis by 10 W/cm 2 was completely climinated with 2 atm of hydrostatic pressure. The reduction in lysis per unit increase in atmospheric pressure was comparable for both ultrasound intensities

  11. Ultrasonic and metallographic studies on AISI 4140 steel exposed to hydrogen at high pressure and temperature

    Science.gov (United States)

    Oruganti, Malavika

    This thesis conducts an investigation to study the effects of hydrogen exposure at high temperature and pressure on the behavior of AISI 4140 steel. Piezoelectric ultrasonic technique was primarily used to evaluate surface longitudinal wave velocity and defect geometry variations, as related to time after exposure to hydrogen at high temperature and pressure. Critically refracted longitudinal wave technique was used for the former and pulse-echo technique for the latter. Optical microscopy and scanning electron microscopy were used to correlate the ultrasonic results with the microstructure of the steel and to provide better insight into the steel behavior. The results of the investigation indicate that frequency analysis of the defect echo, determined using the pulse-echo technique at regular intervals of time, appears to be a promising tool for monitoring defect growth induced by a high temperature and high pressure hydrogen-related attack.

  12. Ultrasonic phased array examination of circumferential weld joint in reactor pressure vessel of BWR

    Energy Technology Data Exchange (ETDEWEB)

    Nanekar, Paritosh, E-mail: pnanekar@barc.gov.in [Quality Assurance Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Jothilakshmi, N. [Quality Assurance Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Jayakumar, T. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2013-12-15

    Highlights: • Phased array technique developed for weld joint inspection in BWR pressure vessel. • Simulation studies were carried out for conventional and phased array probe. • Conventional ultrasonic test shows in-adequate weld coverage and poor resolution. • Focused sound beam in phased array results in good resolution and sensitivity. • Ultrasonic phased array technique is validated on mock-up with reference defects. - Abstract: The weld joints in the reactor pressure vessel (RPV) of Boiling Water Reactors (BWR) are required to be examined periodically for assurance of structural integrity. Ultrasonic phased array examination technique has been developed in authors’ laboratory for inspection of the top flange to shell circumferential weld joint in RPV of BWRs, which are in operation in India since the late 1960s. The development involved detailed simulation studies for computation of focal laws followed by validation on mock-up. The paper brings out the limitations of the conventional ultrasonic technique and how this can be overcome by the phased array approach for the weld joint under consideration. The phased array technique was successfully employed for field examination of this weld joint in RPV during the re-fuelling outage.

  13. Relationship between ultrasonically detected phasic antral contractions and antral pressure.

    Science.gov (United States)

    Hveem, K; Sun, W M; Hebbard, G; Horowitz, M; Doran, S; Dent, J

    2001-07-01

    The relationships between gastric wall motion and intraluminal pressure are believed to be major determinants of flows within and from the stomach. Gastric antral wall motion and intraluminal pressures were monitored in five healthy subjects by concurrent antropyloroduodenal manometry and transabdominal ultrasound for 60 min after subjects drank 500 ml of clear soup. We found that 99% of antral contractions detected by ultrasound were propagated aborally, and 68% of contractions became lumen occlusive at the site of the ultrasound marker. Of the 203 contractions detected by ultrasound, 53% were associated with pressure events in the manometric reference channel; 86% of contractions had corresponding pressure events detectable somewhere in the antrum. Contractions that occluded the lumen were more likely to be associated with a pressure event in the manometric reference channel (P < 0.01) and to be of greater amplitude (P < 0.01) than non-lumen-occlusive contractions. We conclude that heterogeneous pressure event patterns in the antrum occur despite a stereotyped pattern of contraction propagation seen on ultrasound. Lumen occlusion is more likely to be associated with higher peak antral pressure events.

  14. MODELLING OF RING-SHAPED ULTRASONIC WAVEGUIDES FOR TESTING OF MECHANICAL PROPERTIES AND THERAPEUTIC TREATMENT OF BIOLOGICAL TISSUES

    Directory of Open Access Journals (Sweden)

    V. T. Minchenya

    2011-01-01

    Full Text Available The article presents results of modelling of ring-shaped waveguide tool for ultrasonic treatment of biological materials, particularly malignant tumours, and testing of their mechanical properties. Harmonic analysis of forced flexural vibration of the waveguide using ANSYS software and APDL programming language was implemented for determination of waveguide geometric parameters providing its resonance for the given excitation frequency. The developed finite element model accounts for interaction between the waveguide and tumour tissue as well as initial prestressing of tissue radially compressed by the waveguide. Resonant curves of the waveguide in terms of its thickness and diameter are calculated and presented. Principle of application of the developed modeling technique for extraction of diagnostic data on mechanical properties of biological tissues is described.

  15. Reproduction of pressure field in ultrasonic-measurement-integrated simulation of blood flow.

    Science.gov (United States)

    Funamoto, Kenichi; Hayase, Toshiyuki

    2013-07-01

    Ultrasonic-measurement-integrated (UMI) simulation of blood flow is used to analyze the velocity and pressure fields by applying feedback signals of artificial body forces based on differences of Doppler velocities between ultrasonic measurement and numerical simulation. Previous studies have revealed that UMI simulation accurately reproduces the velocity field of a target blood flow, but that the reproducibility of the pressure field is not necessarily satisfactory. In the present study, the reproduction of the pressure field by UMI simulation was investigated. The effect of feedback on the pressure field was first examined by theoretical analysis, and a pressure compensation method was devised. When the divergence of the feedback force vector was not zero, it influenced the pressure field in the UMI simulation while improving the computational accuracy of the velocity field. Hence, the correct pressure was estimated by adding pressure compensation to remove the deteriorating effect of the feedback. A numerical experiment was conducted dealing with the reproduction of a synthetic three-dimensional steady flow in a thoracic aneurysm to validate results of the theoretical analysis and the proposed pressure compensation method. The ability of the UMI simulation to reproduce the pressure field deteriorated with a large feedback gain. However, by properly compensating the effects of the feedback signals on the pressure, the error in the pressure field was reduced, exhibiting improvement of the computational accuracy. It is thus concluded that the UMI simulation with pressure compensation allows for the reproduction of both velocity and pressure fields of blood flow. Copyright © 2012 John Wiley & Sons, Ltd.

  16. Ultrasonic inspection of the Calder Hall and Chaplecross reactor pressure vessels

    International Nuclear Information System (INIS)

    Pennick, A.M.

    1993-01-01

    This paper describes the ultrasonic inspection surveys that have recently been carried out on the Calder Hall and Chapelcross Magnox steel reactor pressure vessels. The development of the inspection system, which is based on the Rediman manipulator and uses the Sonomatic Zipscan equipment and Time-of-Flight diffraction techniques is discussed. The inspection results are presented and compared with the original inspection findings and limiting crack sizes. (author)

  17. Preliminary investigation of ultrasonic shear wave holography with a view to the inspection of pressure vessels

    International Nuclear Information System (INIS)

    Aldridge, E.E.; Clare, A.B.; Shepherd, D.A.

    1975-01-01

    The manner in which holography would fit into the general scheme of pressure vessel inspection is discussed. Compared to conventional A, B and C presentations holography requires a different processing of the ultrasonic signal and a mechanical scan which may be more demanding than that normally provided for a C display. Preliminary results are presented of the examination of artificial defects in steel plate using shear wave holography. (author)

  18. Enhancement of submarine pressure hull steel ultrasonic inspection using imaging and artificial intelligence

    Science.gov (United States)

    Hay, D. Robert; Brassard, Michel; Matthews, James R.; Garneau, Stephane; Morchat, Richard

    1995-06-01

    The convergence of a number of contemporary technologies with increasing demands for improvements in inspection capabilities in maritime applications has created new opportunities for ultrasonic inspection. An automated ultrasonic inspection and data collection system APHIUS (automated pressure hull intelligent ultrasonic system), incorporates hardware and software developments to meet specific requirements for the maritime vessels, in particular, submarines in the Canadian Navy. Housed within a hardened portable computer chassis, instrumentation for digital ultrasonic data acquisition and transducer position measurement provide new capabilities that meet more demanding requirements for inspection of the aging submarine fleet. Digital data acquisition enables a number of new important capabilites including archiving of the complete inspection session, interpretation assistance through imaging, and automated interpretation using artificial intelligence methods. With this new reliable inspection system, in conjunction with a complementary study of the significance of real defect type and location, comprehensive new criteria can be generated which will eliminate unnecessary defect removal. As a consequence, cost savings will be realized through shortened submarine refit schedules.

  19. Ultrasonically determined fill pressure and density in closed spherical shells

    International Nuclear Information System (INIS)

    Asaki, T.J.

    1998-01-01

    Experiments have been conducted in which the D 2 fill pressure has been determined for several closed millimeter-size aluminum and beryllium shells. The vibrational resonance frequency spectrum of the shells was used to calculate the sound velocity of the interior gas. This velocity, along with the equation-of-state, determined the gas pressure and density. The accuracy in determining the fill conditions is within 0.5% in both pressure and density for near critical density (ρ approx-gt 9 mol/L) gas over a wide range of temperatures (190 K to 300 K). Reduced accuracy was apparent at low density. An attempt was made to determine the fill density of one shell by acoustic observation of the dew point temperature. While this temperature was recorded very accurately, the uncertainty in the saturated vapor density curve near the critical point yielded inaccurate results. These methods were shown to be unaffected by small deviations in the sphericity of the gas-filled cavity

  20. Standard-free Pressure Measurement by Ultrasonic Interferometry in a Multi-Anvil Device

    Science.gov (United States)

    Mueller, H. J.; Lathe, C.; Schilling, F. R.; Lauterjung, J.

    2002-12-01

    A key question to all high pressure research arises from the reliability of pressure standards. There is some indication and discussion of an uncertainty of 10-20% for higher pressures in all standards. Simultaneous and independent investigation of the dynamical (ultrasonic interferometry of elastic wave velocities) and static (XRD-measurement of the pressure-induced volume decline) compressibility on a sample reveal the possibility of a standard-free pressure calibration (see Getting, 1998) and, consequently an absolute pressure measurement. Ultrasonic interferometry is used to measure velocities of elastic compressional and shear waves in the multi-anvil high pressure device MAX80 at HASYLAB Hamburg enabling simultaneous XRD and ultrasonic experiments. Two of the six anvils were equipped with overtone polished lithium niobate transducers of 33.3 MHz natural frequency, for generation and detection of ultrasonic waves with a frequency sweep between 5 and 55 MHz. Different buffer - reflector combinations were tested to optimize the critical interference between both sample echoes. NaCl powder of 99.5 % purity (analytical grade by Merck) was used as starting material for manufacturing the samples used as pressure calibrant after Decker (1971). The medium grain size was 50 μm. The powder was pressed to a crude sample cylinder of 10 mm diameter and a length of 20 mm using a load of 6 tons resulting in an effective pressure of 0.25 to 0.3 GPa. The millimeter sized samples (diameter 2.4 mm and 1.6 mm length for 6 mm anvil truncation and diameter 3.1 mm and 1.1 mm length for 3.5 mm anvil truncation) for the high pressure experiments were shaped with a high-precision (+/- 0.5 μm) cylindrical grinding machine and polished at the front faces. From the ultrasonic wave velocity data we calculated the compressibility of NaCl. This requires in situ density data. Therefore the sample deformation during the high pressure experiments was analyzed in detail and the results were

  1. High-pressure behavior of amorphous selenium from ultrasonic measurements and Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    He, Z.; Liu, X. R.; Hong, S. M., E-mail: hpswjtu@gmail.com, E-mail: smhong@home.swjtu.edu.cn [Laboratory of High Pressure Physics, Southwest Jiaotong University, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Chengdu 610031 (China); Wang, Z. G. [National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900 (China); Zhu, H. Y. [State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012 (China); Peng, J. P. [School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China)

    2014-07-07

    The high-pressure behavior of melt-quenched amorphous selenium (a-Se) has been investigated via ultrasonic measurements and Raman scattering at room temperature. The ultrasonic measurements were conducted on a-Se in a multi-anvil apparatus with two different sample assemblies at pressures of up to 4.5 and 4.8 GPa. We discovered that similar kinks occur in the slopes of the pressure dependence characteristics of the travel time and the sound velocity in both shear and longitudinal waves in the 2.0–2.5 GPa range. These kinks are independent of the sample assemblies, indicating an intrinsic transformation of the a-Se. Additionally, we deduced the pressure-volume relationship of a-Se from the sound velocity characteristics using the Birch–Murnaghan equation of state, and the results agreed well with those of previous reports. In situ high-pressure Raman scattering measurements of a-Se were conducted in a diamond anvil cell with an 830 nm excitation line up to a pressure of 4.3 GPa. We found that the characteristic band of a-Se at ∼250 cm{sup −1} experienced a smooth shift to a lower frequency with pressure, but a sharp slope change in the band intensity versus pressure occurred near 2.5 GPa. The results of X-ray diffraction and differential scanning calorimetry measurements indicate that the samples remain in their amorphous states after decompression. Thus, we proposed that the abnormal compression behavior of a-Se in the 2.0–2.5 GPa range can be attributed to pressure-induced local atomic reconfiguration, implying an amorphous-amorphous transition of the elementary selenium.

  2. bcc transition metals under pressure: results from ultrasonic interferometry and diamond-cell experiments

    International Nuclear Information System (INIS)

    Katahara, K.W.; Manghnani, M.H.; Ming, L.C.; Fisher, E.S.

    1976-01-01

    Hydrostatic pressure derivatives of the single-crystal elastic moduli, dC/sub ij//dP, have been measured ultrasonically for b.c.c. Nb--Mo and Ta--W solid solutions. The composition dependence of various electronic properties of these alloys is known to be reasonably well approximated by a rigid-electron-band filling model where e/a, the electron per atom ratio, is the primary parameter. The results indicate that the elastic moduli and their pressure derivatives may also be calculated in such a model. In particular, the dC/sub ij//dP show relatively sharp increases at e/a compositions of 5.4 for Nb--Mo and 5.7 for Ta--W. Both compositions correspond to changes in Fermi surface topology, as deduced from existing band calculations and the rigid band assumption. The results are discussed in the light of related electronic properties and possible geophysical applications. A comparison is also made between ultrasonic results and X-ray diffraction data for Nb. Using diamond-anvil pressure cell, compression of Nb was determined by X-ray diffraction up to 55 kbar in a liquid medium under purely hydrostatic conditions, and up to 175 kbar in a solid medium under nonhydrostatic conditions. The data obtained under hydrostatic conditions agree well with the ultrasonic equation of state and shock wave data, whereas the nonhydrostatic results tend to imply either a higher bulk modulus K/sub s/ or a higher (par. deltaK/sub s//par. deltaP)/sub T/

  3. Modeling cavitation in a rapidly changing pressure field - application to a small ultrasonic horn.

    Science.gov (United States)

    Žnidarčič, Anton; Mettin, Robert; Dular, Matevž

    2015-01-01

    Ultrasonic horn transducers are frequently used in applications of acoustic cavitation in liquids. It has been observed that if the horn tip is sufficiently small and driven at high amplitude, cavitation is very strong, and the tip can be covered entirely by the gas/vapor phase for longer time intervals. A peculiar dynamics of the attached cavity can emerge with expansion and collapse at a self-generated frequency in the subharmonic range, i.e. below the acoustic driving frequency. The term "acoustic supercavitation" was proposed for this type of cavitation Žnidarčič et al. (2014) [1]. We tested several established hydrodynamic cavitation models on this problem, but none of them was able to correctly predict the flow features. As a specific characteristic of such acoustic cavitation problems lies in the rapidly changing driving pressures, we present an improved approach to cavitation modeling, which does not neglect the second derivatives in the Rayleigh-Plesset equation. Comparison with measurements of acoustic supercavitation at an ultrasonic horn of 20kHz frequency revealed a good agreement in terms of cavity dynamics, cavity volume and emitted pressure pulsations. The newly developed cavitation model is particularly suited for simulation of cavitating flow in highly fluctuating driving pressure fields. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Analysis of an ultrasonic level device for in-core Pressurized Water Reactor coolant detection

    International Nuclear Information System (INIS)

    Johnson, K.R.

    1981-01-01

    A rigorous semi-empirical approach was undertaken to model the response of an ultrasonic level device (ULD) for application to in-core coolant detection in Pressurized Water Reactors (PWRs). An equation is derived for the torsional wave velocity v/sub t phi/ in the ULD. Existing data reduction techniques were analyzed and compared to results from use of the derived equation. Both methods yield liquid level measurements with errors of approx. 5%. A sensitivity study on probe performance at reactor conditions predicts reduced level responsivity from data at lower temperatures

  5. Inspection device for external examination of pressure vessels, preferably for ultrasonic testing of reactor vessels

    International Nuclear Information System (INIS)

    Figlhuber, D.; Gallwas, J.; Weber, R.; Weber, J.

    1978-01-01

    The inspection device is placed in the annular gap between pressure vessel and biological shield of the BWR. In the annulus there is arranged at least one longitudinal rail which has got vertical guideways. Along it there can be moved on testing paths a manipulator with the ultrasonic search unit. The manipulator drive is outside of the inspection annulus. It is coupled to the manipulator by means of a tension member being guided over a reversing unit mounted at the upper end of the longitudinal rail. As a tension member there may be used a drag chain; the drive and the reversing unit are provided with corresponding chain wheels. (DG) [de

  6. Analysis on the anisotropic electromechanical properties of lead magnoniobate titanate single crystal for ring type ultrasonic motors

    Directory of Open Access Journals (Sweden)

    Xiang Shi

    2016-11-01

    Full Text Available This work discussed the optimized cut of single crystal lead magnoniobate titanate (PMNT for use of ring type travelling wave ultrasonic motors (USMs, according to anisotropic analysis on electromechanical properties. The selection criterion of crystal orientation relies on the circular uniformity of the induced travelling wave amplitude on the stator surface. By calculating the equivalent elastic coefficient c11 and lateral piezoelectric constant d31, the optimal crystal orientations were proposed for PMNT single crystals poled along different directions. For single crystal poled along c directions, the optimal orientation lies along [001]c with d31=-1335pC/N and k31=0.87. The crystallographic orientation [025]c is the optimized orientation for single crystals poled along c direction with d31=199pC/N and k31=0.55. The optimal orientation of 1R configuration is [332¯]c with a large enhancement of d31 = 1201 and k31=0.92.

  7. Ultrasonic nebulization extraction/low pressure photoionization mass spectrometry for direct analysis of chemicals in matrices.

    Science.gov (United States)

    Liu, Chengyuan; Zhu, Yanan; Zhou, Zhongyue; Yang, Jiuzhong; Qi, Fei; Pan, Yang

    2015-09-03

    A novel ultrasonic nebulization extraction/low-pressure photoionization (UNE-LPPI) system has been designed and employed for the rapid mass spectrometric analysis of chemicals in matrices. An ultrasonic nebulizer was used to extract the chemicals in solid sample and nebulize the solvent in the nebulization cell. Aerosols formed by ultrasonic were evaporated by passing through a transferring tube, and desolvated chemicals were ionized by the emitted light (10.6 eV) from a Krypton discharge lamp at low pressure (∼68 Pa). First, a series of semi/non-volatile compounds with different polarities, such as polycyclic aromatic hydrocarbons (PAHs), amino acids, dipeptides, drugs, nucleic acids, alkaloids, and steroids were used to test the system. Then, the quantification capability of UNE-LPPI was checked with: 1) pure chemicals, such as 9,10-phenanthrenequinone and 1,4-naphthoquinone dissolved in solvent; 2) soil powder spiked with different amounts of phenanthrene and pyrene. For pure chemicals, the correlation coefficient (R(2)) for the standard curve of 9,10-phenanthrenequinone in the range of 3 ng-20 μg mL(-1) was 0.9922, and the measured limits of detection (LOD) was 1 ng ml(-1). In the case of soil powder, linear relationships for phenanthrene and pyrene from 10 to 400 ng mg(-1) were obtained with correlation coefficients of 0.9889 and 0.9893, respectively. At last, the feasibility of UNE-LPPI for the detection of chemicals in real matrices such as tablets and biological tissues (tea, Citrus aurantium peel and sage (Salvia officinalis) leaf) were successfully demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Ultrasonic Reflectometry for Monitoring the Effect of Pressure on Sludge Fouling of MF Membranes

    DEFF Research Database (Denmark)

    Jørgensen, Mads Koustrup; Kujundzic, Elmira; Greenberg, Alan

    Membrane fouling remains the key limitation for the widespread use of membrane bioreactors (MBR) for wastewater treatment. This constraint has led to an increasing number of studies that examine the influence of various operational parameters and physicochemical properties on fouling layer...... formation and characteristics. In other membrane applications real-time monitoring has proven to be useful by providing a more quantitative characterization of fouling layer formation [1]. One such technique, ultrasonic reflectometry (UR), has been successfully used to detect fouling formed by a wide range...... of the effect of pressure on the fouling layer structure. The ability of UR to detect and monitor sludge fouling was studied in a series of replicated experiments of 15, 30 and 60-min duration that used commercial microfiltration (MF) membranes at a transmembrane pressure of 15 kPa. By analyzing the peak...

  9. Capacitive Micro Pressure Sensor Integrated with a Ring Oscillator Circuit on Chip

    Directory of Open Access Journals (Sweden)

    Cheng-Yang Liu

    2009-12-01

    Full Text Available The study investigates a capacitive micro pressure sensor integrated with a ring oscillator circuit on a chip. The integrated capacitive pressure sensor is fabricated using the commercial CMOS (complementary metal oxide semiconductor process and a post-process. The ring oscillator is employed to convert the capacitance of the pressure sensor into the frequency output. The pressure sensor consists of 16 sensing cells in parallel. Each sensing cell contains a top electrode and a lower electrode, and the top electrode is a sandwich membrane. The pressure sensor needs a post-CMOS process to release the membranes after completion of the CMOS process. The post-process uses etchants to etch the sacrificial layers, and to release the membranes. The advantages of the post-process include easy execution and low cost. Experimental results reveal that the pressure sensor has a high sensitivity of 7 Hz/Pa in the pressure range of 0–300 kPa.

  10. Influence of fused aromatic ring on the stability of charge transfer complex between iodine and some five membered heterocyclic molecules through ultrasonic and spectral studies

    Science.gov (United States)

    Ulagendran, V.; Balu, P.; Kannappan, V.; Kumar, R.; Jayakumar, S.

    2017-08-01

    The charge transfer (CT) interaction between two fused heterocyclic compounds with basic pyrrole group as donors, viz., indole (IND) and carbazole (CAR), and iodine (acceptor) in DMSO medium is investigated by ultrasonic and UV-visible spectral methods at 303 K. The formation of CT complex in these systems is established from the trend in acoustical and excess thermo acoustical properties with molar concentration. The frequency acoustic spectra (FAS) is also carried out on these two systems for two fixed concentrations 0.002 M and 0.02 M, and in the frequency range 1 MHz-10 MHz to justify the frequency chosen for ultrasonic study. The absorption coefficient values in solution are computed and discussed. The formation constants of these complexes are determined using Kannappan equation in ultrasonic method. The formation of 1:1 complexes between iodine and IND, CAR was established by the theory of Benesi - Hildebrand in the UV-visible spectroscopic method. The stability constants of the CT complexes determined by spectroscopic and ultrasonic methods show a similar trend. These values also indicate that the presence of fused aromatic ring influences significantly when compared with K values of similar CT complexes of parent five membered heterocyclic compound (pyrrole) reported by us earlier.

  11. Ultrasonic in-service testing of pressure vessel bodies of nuclear power reactors

    International Nuclear Information System (INIS)

    Obraz, J.

    1978-01-01

    In-service ultrasonic testing of reactor pressure vessels is described using a system of probes for simultaneous testing of material or weld joint thicknesses. The signal is transmitted from a common output via a 30 m long cable to electronic evaluation equipment. The methods are described of ultrasonic detection of fatigue cracks. The static calculation of the dependence of echo amplitudes on crack orientation and the dynamic calculation of the crack orientation effect are described for the indirect reflection technique. In testing, angular probes with gap-type acoustic coupling operating at a frequency of 2 MHz were preferably used. For detecting planar defects of more than 10 mm in size inclined by more than +-10deg probes operating at a frequency of 1 MHz were more advantageous. The direct reflection technique is suitable for detecting defects near the surface (10 to 20 mm) and for cases when the indirect reflection technique cannot be used. For this technique a focusing probe operating at a frequency of 2 MHz is suitable. The strong dependence of the echo amplitude on the crack depth is a disadvantage of the technique. Defects near the surface, i.e., immediately under cladding are best detected by means of a double probe transmitting transversal waves at an angle of 60deg. Experimental measurements were carried out on materials with artificial defects of the type of bores with flat bottom. (J.P.)

  12. Effects of operator time pressure and noise on manual ultrasonic testing

    International Nuclear Information System (INIS)

    Enkvist, J.; Edland, A.; Svenson, O.

    2002-01-01

    In earlier studies of manual ultrasonic testing, great variations have been found in operator performance, often attributed to operator fatigue. However, no conclusive findings have been reported. In the present study, twenty operators performed manual ultrasonic inspections of six test-pieces with manufactured flaws. The operators performed the inspections under stress (high arousal - time pressure and noise) and no-stress conditions; one condition the first day and the other the second and last day. According to the Yerkes-Dodson Law there is an optimal arousal level where performance is highest. It was hypothesised that the stress condition led to a level of arousal so high that it would affect the results negatively. However, contrary to the hypotheses it was found that the manipulation increased operator performance. Operators with the stress condition day 1 performed better than the other operators (under the no-stress condition). This was interpreted as the 'stress first' (group 1) operators had established efficient performance patterns the first day - affecting also the second day. Operators beginning with stress condition also tended to be more motivated. It was concluded that operator performance is affected by arousal. (author)

  13. Sensitivity enhancement of fiber loop cavity ring-down pressure sensor.

    Science.gov (United States)

    Jiang, Yajun; Yang, Dexing; Tang, Daqing; Zhao, Jianlin

    2009-11-10

    We present a theoretical and experimental study on sensitivity enhancement of a fiber-loop cavity ring-down pressure sensor. The cladding of the sensing fiber is etched in hydrofluoric acid solution to enhance its sensitivity. The experimental results demonstrate that the pressure applied on the sensing fiber is linearly proportional to the difference between the reciprocals of the ring-down time with and without pressure, and the relative sensitivity exponentially increases with decreasing the cladding diameter. When the sensing fiber is etched to 41.15 microm, its sensitivity is about 36 times that of nonetched fiber in the range of 0 to 32.5 MPa. The measured relative standard deviation of the ring-down time is about 0.15% and, correspondingly, the least detectable loss is about 0.00069 dB.

  14. X-ray elastography: Modification of x-ray phase contrast images using ultrasonic radiation pressure

    International Nuclear Information System (INIS)

    Hamilton, Theron J.; Bailat, Claude; Rose-Petruck, Christoph; Diebold, Gerald J.; Gehring, Stephan; Laperle, Christopher M.; Wands, Jack

    2009-01-01

    The high resolution characteristic of in-line x-ray phase contrast imaging can be used in conjunction with directed ultrasound to detect small displacements in soft tissue generated by differential acoustic radiation pressure. The imaging method is based on subtraction of two x-ray images, the first image taken with, and the second taken without the presence of ultrasound. The subtraction enhances phase contrast features and, to a large extent, removes absorption contrast so that differential movement of tissues with different acoustic impedances or relative ultrasonic absorption is highlighted in the image. Interfacial features of objects with differing densities are delineated in the image as a result of both the displacement introduced by the ultrasound and the inherent sensitivity of x-ray phase contrast imaging to density variations. Experiments with ex vivo murine tumors and human tumor phantoms point out a diagnostic capability of the method for identifying tumors.

  15. Operational aspects of the Calder Hall and Chapelcross pressure vessel ultrasonic inspections

    International Nuclear Information System (INIS)

    Bithell, S.J.; Howard, S.R.

    1993-01-01

    As a consequence of the NII's assessment of the Calder Hall and Chapelcross Long Term Safety Review, BNFplc were required to demonstrate the integrity of the Reactor Pressure Vessels through a programme of volumetric seam weld inspection. Existing equipment proved to be inadequate and necessitated the design and manufacture of a remote power manipulator and ultrasonic scanning package. Calder Hall Operations Department and Sellafield Technical Department, working closely with contract staff, completed the first stage of this technically demanding task within 14 months of the project's initiation, resulting in the first deployment of ''REDIMAN'' in March 1991. The design of the new equipment, and the technical and operational difficulties which were overcome by the Inspection Team are outlined. (author)

  16. Ultrasonic determination of the elastic moduli and their pressure dependences in very dense YBa2Cu3O7-x

    International Nuclear Information System (INIS)

    Cankurtaran, M.; Saunders, G.A.; Goretta, K.C.; Poeppel, R.B.

    1991-12-01

    The effects of hydrostatic pressure and temperature have been measured on the velocities of longitudinal and shear ultrasonic waves propagated in a very dense (96% of theoretical density) ceramic specimen of YBa 2 Cu 3 O 7-x . In YBa 2 Cu 3 O 7-x ceramics with such a high density the effects of porosity on the elastic properties should be much reduced. Nevertheless the bulk modulus of this dense material has the same small magnitude (∼ 55GPa) as that measured ultrasonically in much less dense YBa 2 Cu 3 O 7-x ceramics. The temperature dependences of the velocities of longitudinal and shear ultrasonic waves, which have been measured between 10 K and 300 K, show the step-like increase at 200 K on cooling and a similar decrease at 225 K during warming with hysteresis in the range 190 K to 235 K that has previously been observed in less dense ceramics and tentatively attributed to a phase transformation. The pressure dependences of both mode velocities for dense YBa 2 Cu 3 O 7-x ceramic show a pronounced change of slope at a pressure P c . For pressures below and above P c the pressure dependence of ultrasonic velocity is essentially linear. Above the knee, the enormous pressure dependences of the longitudinal mode velocity and hence of the bulk modulus persist. The temperature dependences of pressure derivatives of elastic stiffnesses and bulk modulus have been measured between 250 K and 295 K. The pressure P c at which the kink occurs decreases almost linearly with decreasing temperature and extrapolates to atmospheric pressure at about 220 K

  17. New intraocular pressure measurement method using reflected pneumatic pressure from cornea deformed by air puff of ring-type nozzle.

    Science.gov (United States)

    Kim, Hyung Jin; Seo, Yeong Ho; Kim, Byeong Hee

    2017-01-01

    In this study, a non-contact type intraocular pressure (IOP) measuring system using reflected pneumatic pressure is proposed to overcome the disadvantages of existing measurement systems. A ring-type nozzle, a key component in the proposed system, is designed via computational fluid analysis. It predicts the reflected pneumatic pressure based on the nozzle exit angle and inner and outer diameters of the nozzle, which are 30°, 7 mm, and 9 mm, respectively. Performance evaluation is conducted using artificial eyes fabricated using polydimethylsiloxane with the specifications of human eyes. The IOP of the fabricated artificial eyes is adjusted to 10, 30, and 50 mm Hg, and the reflected pneumatic pressure is measured as a function of the distance between the ring-type nozzle and artificial eye. The measured reflected pneumatic pressure is high when the measurement distance is short and eye pressure is low. The cornea of an artificial eye is significantly deformed at a low IOP, and the applied pneumatic pressure is more concentrated in front of the ring-type nozzle because of the deformed cornea. Thus, the reflected pneumatic pressure at a low IOP has more inflows into the pressure sensor inserted inside the nozzle. The sensitivity of the output based on the IOP at measurement distances between 3-5 mm is -0.0027, -0.0022, -0.0018, -0.0015, and -0.0012. Sensitivity decreases as the measurement distance increases. In addition, the reflected pneumatic pressure owing to the misalignment at the measurement distances of 3-5 mm is not affected within a range of 0.5 mm. Therefore, the measurement range is acceptable up to a 1 mm diameter from the center of an artificial eye. However, the accuracy gradually decreases as the reflected pneumatic pressure from a misalignment of 1 mm or more decreases by 26% or more.

  18. The effect of surface pressure modification on the speed of vortex rings

    Energy Technology Data Exchange (ETDEWEB)

    Partridge, Matthew; Davis, Frank; Higson, Seamus P J [Centre of Biomedical Imaging, Cranfield University, Cranfield MK43 0AL (United Kingdom); James, Stephen W; Tatam, Ralph P, E-mail: f.davis@cranfield.ac.uk [Engineering Photonics, School of Engineering, Cranfield University, Cranfield MK43 0AL (United Kingdom)

    2014-10-01

    A series of experiments investigating the relationship between surface pressure, monolayer elasticity and the speed of vortex rings is presented. A drop of water, when touched to the surface of a larger body of water, will coalesce and form a vortex ring that moves perpendicularly to the surface of the water. The speed of the vortex ring movement away from the surface of the water has been seen to be sensitive to the presence of monolayer materials. Here we explore the influence of four monolayer forming materials, stearic acid, tricosanoic acid, 4-tert butyl calix[4]arene and calix[4]resorcarene (C11), on the properties of vortex rings. For each material, the speed of the vortex rings through the water was measured at a range of surface pressures. The speed was found to increase in a linear fashion until surface pressures greater than 30 mN m{sup −1}, where the ring’s speed decreased towards the value measured in the absence of a monolayer. Analysis of the results suggests a future route toward a better understanding of the mechanisms involved.

  19. Process for producing curved surface of membrane rings for large containers, particulary for prestressed concrete pressure vessels of nuclear reactors

    International Nuclear Information System (INIS)

    Kumpf, H.

    1977-01-01

    Membrane rings for large pressure vessels, particularly for prestressed-concrete pressure vessels, often have curved surfaces. The invention describes a process of producing these at site, which is particularly advantageous as the forming and installation of the vessel component coincide. According to the invention, the originally flat membrane ring is set in a predetermined position, is then pressed in sections by a forming tool (with a preformed support ring as opposite tool), and shaped. After this, the shaped parts are welded to the ring-shaped wall parts of the large vessel. The manufacture of single and double membrane rings arrangements is described. (HP) [de

  20. Ring-shaped inductive sensor design and application to pressure sensing

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Myoung Gyu; Baek, Seong Ki; Park, Young Woo [Dept. of Mechatronics Engineering, Chungnam National University, Daejeon (Korea, Republic of); Kim, Sun Young [Samsung Electro-Mechanics, Busan (Korea, Republic of)

    2015-10-15

    Inductive sensors are versatile and economical devices that are widely used to measure a wide variety of physical variables, such as displacement, force, and pressure. In this paper, we propose a simple inductive sensor consisting of a thin partial ring and a coil set. The self-inductance of the sensor was estimated using magnetic circuit analysis and validated through finite element analysis (FEA). The natural frequency of the ring was estimated using Castigliano's theorem and the method of equivalent mass. The estimation was validated through experiments and FEA. A prototype sensor with a signal processing circuit is built and applied to noninvasively sense the pressure inside a flexible tube. The obtained sensor outputs show quadratic behavior with respect to the pressure. When fitted to a quadratic equation, the least-square measurement error was less than 2%. The results confirm the feasibility of pressure sensing using the proposed inductive sensor.

  1. Ring-shaped inductive sensor design and application to pressure sensing

    International Nuclear Information System (INIS)

    Noh, Myoung Gyu; Baek, Seong Ki; Park, Young Woo; Kim, Sun Young

    2015-01-01

    Inductive sensors are versatile and economical devices that are widely used to measure a wide variety of physical variables, such as displacement, force, and pressure. In this paper, we propose a simple inductive sensor consisting of a thin partial ring and a coil set. The self-inductance of the sensor was estimated using magnetic circuit analysis and validated through finite element analysis (FEA). The natural frequency of the ring was estimated using Castigliano's theorem and the method of equivalent mass. The estimation was validated through experiments and FEA. A prototype sensor with a signal processing circuit is built and applied to noninvasively sense the pressure inside a flexible tube. The obtained sensor outputs show quadratic behavior with respect to the pressure. When fitted to a quadratic equation, the least-square measurement error was less than 2%. The results confirm the feasibility of pressure sensing using the proposed inductive sensor

  2. Development of automated ultrasonic device for in-service inspection of ABWR pressure vessel bottom head

    International Nuclear Information System (INIS)

    Kojima, Y.; Matsuyama, A.

    1995-01-01

    An automated device and its controller have been developed for the bottom head weld examination of pressure vessel of Advanced Boiling Water Reactor (ABWR). The internal pump casings and the housings of control rod prevent a conventional ultrasonic device from scanning the required inspection zone. With this reason, it is required to develop a new device to examine the bottom head area of ABWR. The developed device is characterized by the following features. (1) Composed of a mother vehicle and a compact inspection vehicle. They are connected only by an electric wire without using the conventional arm mechanism. (2) The mother vehicle travels on a track and lift up the inspection vehicle to the vessel. (3) The mother vehicle can automatically attach the inspection vehicle to the bottom head, and detach the inspection vehicle from it. (4) Collision avoidance control function with a touch sensor is installed at the front of the inspection vehicle. The device was successfully demonstrated using a mock-up of reactor pressure vessel

  3. Deformation Characteristics and Sealing Performance of Metallic O-rings for a Reactor Pressure Vessel

    Directory of Open Access Journals (Sweden)

    Mingxue Shen

    2016-04-01

    Full Text Available This paper provides a reference to determine the seal performance of metallic O-rings for a reactor pressure vessel (RPV. A nonlinear elastic-plastic model of an O-ring was constructed by the finite element method to analyze its intrinsic properties. It is also validated by experiments on scaled samples. The effects of the compression ratio, the geometrical parameters of the O-ring, and the structure parameters of the groove on the flange are discussed in detail. The results showed that the numerical analysis of the O-ring agrees well with the experimental data, the compression ratio has an important role in the distribution and magnitude of contact stress, and a suitable gap between the sidewall and groove can improve the sealing capability of the O-ring. After the optimization of the sealing structure, some key parameters of the O-ring (i.e., compression ratio, cross-section diameter, wall thickness, sidewall gap have been recommended for application in megakilowatt class nuclear power plants. Furthermore, air tightness and thermal cycling tests were performed to verify the rationality of the finite element method and to reliably evaluate the sealing performance of a RPV.

  4. Deformation characteristics and sealing performance of metallic-O-ring for a reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Ming Xue; Peng, Xudong; Xie, Linjun; Meng, Xiang Kai [Engineering Research Center of Process Equipment and Its Remanufacture, Ministry of Education, Zhejiang University of Technology, Hangzhou (China); Li, Xing Gen [Ningbo Tiansheng Sealing Packing Co., Ltd., Ningbo (China)

    2016-04-15

    This paper provides a reference to determine the seal performance of metallic O-rings for a reactor pressure vessel (RPV). A nonlinear elastic-plastic model of an O-ring was constructed by the finite element method to analyze its intrinsic properties. It is also validated by experiments on scaled samples. The effects of the compression ratio, the geometrical parameters of the O-ring, and the structure parameters of the groove on the flange are discussed in detail. The results showed that the numerical analysis of the O-ring agrees well with the experimental data, the compression ratio has an important role in the distribution and magnitude of contact stress, and a suitable gap between the sidewall and groove can improve the sealing capability of the O-ring. After the optimization of the sealing structure, some key parameters of the O-ring (i.e., compression ratio, cross-section diameter, wall thickness, sidewall gap) have been recommended for application in megakilowatt class nuclear power plants. Furthermore, air tightness and thermal cycling tests were performed to verify the rationality of the finite element method and to reliably evaluate the sealing performance of a RPV.

  5. A study on the sealing performance of metallic C-rings in reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Xiaohong, E-mail: jiaxh@mail.tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Chen, Huaming [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Li, Xinggen [Ningbo Tiansheng Sealing Packing Co., Ltd, Ningbo 315302 (China); Wang, Yuming [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Wang, Longke [Eaton Corporation, MN (United States)

    2014-10-15

    Highlights: • FE analysis on compression–resilience of metallic C-ring is performed and validated by experiments. • Model of RPV sealing system including the C-rings is developed. • Deformation data from factory hydraulic test of the RPV are used to verify the model. • C-rings’ behavior under designing condition is analyzed. • The model provides a reliable evaluation on the sealing performance of RPV. - Abstract: Double metallic C-rings are used in pressure vessel of pressurized water reactor (PWR) to seal the bolt-connected flanges. To evaluate the sealing performance, it is necessary to study both the C-rings’ intrinsic properties and their behavior in reactor pressure vessel (RPV) under various loading conditions. The compression–resilience property and linear load are the basic information to evaluate the performance of a well-designed C-ring's. An equivalent model of C-ring is constructed by means of ANSYS to analyze its intrinsic properties, and is also validated by experiments on scaled samples. This model is applied to develop a 2D-axisymmetric FE model of sealing system including RPV and C-rings with the consideration of nonlinear material, contacting problem and multiple coupled effects. The simulation results of RPV deformation under the hydraulic test condition agree well with the data of factory hydraulic test. With the verified model, an analysis under the designing condition is performed to study C-rings’ behavior in the RPV, and then provides a reliable evaluation on the sealing performance of RPV.

  6. Ultrasonic test results for the reactor pressure vessel of the HTTR. Longitudinal welding line of bottom dome

    International Nuclear Information System (INIS)

    Nojiri, Naoki; Ohwada, Hiroyuki; Kato, Yasushi

    2008-06-01

    This paper describes the inspection method, the measured area, etc. of the ultrasonic test of the in-service inspection (ISI) for welding lines of the reactor pressure vessel of the HTTR and the inspection results of the longitudinal welding line of the bottom dome. The pre-service inspection (PSI) results for estimation of occurrence and progression of defects to compare the ISI results is described also. (author)

  7. Reduction of the suction pressure of a liquid ring vacuum pump with a supersonic gas ejector

    Directory of Open Access Journals (Sweden)

    Olšiak Róbert

    2018-01-01

    Full Text Available A supersonic gas ejector in conjunction with a liquid ring vacuum pump is used for creating and maintaining vacuum in a chamber for technological purposes. In this paper the authors submit an overview about the problematics of suction pressure reduction with a supersonic gas ejector used as a pre-stage of a liquid ring vacuum pump. This system has also the function of a cavitation protection due to the higher pressure present at the suction throat of the vacuum pump. A part of this paper is devoted to the governing equations used at the definition of the flow through an ejector. The experimental studies are then carried out in or own laboratory for verification purposes.

  8. Buckling behaviour of imperfect ring-stiffened cone-cylinder intersections under internal pressure

    International Nuclear Information System (INIS)

    Zhao, Y.

    2005-01-01

    Cone-cylinder intersections are used commonly in pressure vessels and piping. In the case of a cone large end-to-cylinder intersection under internal pressure, the intersection is subject to a large circumferential compressive force. While both the cone and the cylinder may be locally thickened to strengthen the intersection, it is often desirable and convenient to provide an annular plate ring at the cone-to-cylinder joint to supplement local thickening or as an alternative strengthening measure, leading to a ring-stiffened cone-cylinder intersection. Only limited work has been carried out specifically on ring-stiffened cone-cylinder intersections under internal pressure. This paper presents the first experimental study on such intersections. In addition to the presentation of test results including geometric imperfections, failure behaviour and the determination of buckling mode and load based on displacement measurements, results from nonlinear bifurcation analysis using the perfect shape and nonlinear analysis using the measured imperfect shape are presented and compared with the experimental results

  9. Head Injury and Intracranial Pressure Monitor Using Ultrasonic and Low-Frequency Acoustic (ULFA) Detection

    National Research Council Canada - National Science Library

    Vo-Dinh, Tuan

    2001-01-01

    The main objective of this research project is the development of a non-invasive method and instrument for head injury detection and monitoring using a new approach based on ultrasonic and low-frequency acoustic (ULFA...

  10. Head Injury and Intracranial Pressure Monitor Using Ultrasonic and Low-Frequency (ULFA) Detection

    National Research Council Canada - National Science Library

    Vo-Dinh, Tuan

    2000-01-01

    The main objective of this research project is the development of a non-invasive method and instrument for head injury detection and monitoring using a new approach based on ultrasonic and low-frequency acoustic (ULFA...

  11. Novel High Temperature Capacitive Pressure Sensor Utilizing SiC Integrated Circuit Twin Ring Oscillators

    Science.gov (United States)

    Scardelletti, M.; Neudeck, P.; Spry, D.; Meredith, R.; Jordan, J.; Prokop, N.; Krasowski, M.; Beheim, G.; Hunter, G.

    2017-01-01

    This paper describes initial development and testing of a novel high temperature capacitive pressure sensor system. The pressure sensor system consists of two 4H-SiC 11-stage ring oscillators and a SiCN capacitive pressure sensor. One oscillator has the capacitive pressure sensor fixed at one node in its feedback loop and varies as a function of pressure and temperature while the other provides a pressure-independent reference frequency which can be used to temperature compensate the output of the first oscillator. A two-day repeatability test was performed up to 500C on the oscillators and the oscillator fundamental frequency changed by only 1. The SiCN capacitive pressure sensor was characterized at room temperature from 0 to 300 psi. The sensor had an initial capacitance of 3.76 pF at 0 psi and 1.75 pF at 300 psi corresponding to a 54 change in capacitance. The integrated pressure sensor system was characterized from 0 to 300 psi in steps of 50 psi over a temperature range of 25 to 500C. The pressure sensor system sensitivity was 0.113 kHzpsi at 25C and 0.026 kHzpsi at 500C.

  12. A pressure core ultrasonic test system for on-board analysis of gas hydrate-bearing sediments under in situ pressures.

    Science.gov (United States)

    Yang, Lei; Zhou, Weihua; Xue, Kaihua; Wei, Rupeng; Ling, Zheng

    2018-05-01

    The enormous potential as an alternative energy resource has made natural gas hydrates a material of intense research interest. Their exploration and sample characterization require a quick and effective analysis of the hydrate-bearing cores recovered under in situ pressures. Here a novel Pressure Core Ultrasonic Test System (PCUTS) for on-board analysis of sediment cores containing gas hydrates at in situ pressures is presented. The PCUTS is designed to be compatible with an on-board pressure core transfer device and a long gravity-piston pressure-retained corer. It provides several advantages over laboratory core analysis including quick and non-destructive detection, in situ and successive acoustic property acquisition, and remission of sample storage and transportation. The design of the unique assembly units to ensure the in situ detection is demonstrated, involving the U-type protecting jackets, transducer precession device, and pressure stabilization system. The in situ P-wave velocity measurements make the detection of gas hydrate existence in the sediments possible on-board. Performance tests have verified the feasibility and sensitivity of the ultrasonic test unit, showing the dependence of P-wave velocity on gas hydrate saturation. The PCUTS has been successfully applied for analysis of natural samples containing gas hydrates recovered from the South China Sea. It is indicated that on-board P-wave measurements could provide a quick and effective understanding of the hydrate occurrence in natural samples, which can assist further resource exploration, assessment, and subsequent detailed core analysis.

  13. A pressure core ultrasonic test system for on-board analysis of gas hydrate-bearing sediments under in situ pressures

    Science.gov (United States)

    Yang, Lei; Zhou, Weihua; Xue, Kaihua; Wei, Rupeng; Ling, Zheng

    2018-05-01

    The enormous potential as an alternative energy resource has made natural gas hydrates a material of intense research interest. Their exploration and sample characterization require a quick and effective analysis of the hydrate-bearing cores recovered under in situ pressures. Here a novel Pressure Core Ultrasonic Test System (PCUTS) for on-board analysis of sediment cores containing gas hydrates at in situ pressures is presented. The PCUTS is designed to be compatible with an on-board pressure core transfer device and a long gravity-piston pressure-retained corer. It provides several advantages over laboratory core analysis including quick and non-destructive detection, in situ and successive acoustic property acquisition, and remission of sample storage and transportation. The design of the unique assembly units to ensure the in situ detection is demonstrated, involving the U-type protecting jackets, transducer precession device, and pressure stabilization system. The in situ P-wave velocity measurements make the detection of gas hydrate existence in the sediments possible on-board. Performance tests have verified the feasibility and sensitivity of the ultrasonic test unit, showing the dependence of P-wave velocity on gas hydrate saturation. The PCUTS has been successfully applied for analysis of natural samples containing gas hydrates recovered from the South China Sea. It is indicated that on-board P-wave measurements could provide a quick and effective understanding of the hydrate occurrence in natural samples, which can assist further resource exploration, assessment, and subsequent detailed core analysis.

  14. High Temperature Capacitive Pressure Sensor Employing a SiC Based Ring Oscillator

    Science.gov (United States)

    Meredith, Roger D.; Neudeck, Philip G.; Ponchak, George E.; Beheim, Glenn M.; Scardelletti, Maximilian; Jordan, Jennifer L.; Chen, Liang-Yu; Spry, David J.; Krawowski, Michael J.; Hunter, Gary W.

    2011-01-01

    In an effort to develop harsh environment electronic and sensor technologies for aircraft engine safety and monitoring, we have used capacitive-based pressure sensors to shift the frequency of a SiC-electronics-based oscillator to produce a pressure-indicating signal that can be readily transmitted, e.g. wirelessly, to a receiver located in a more benign environment. Our efforts target 500 C, a temperature well above normal operating conditions of commercial circuits but within areas of interest in aerospace engines, deep mining applications and for future missions to the Venus atmosphere. This paper reports for the first time a ring oscillator circuit integrated with a capacitive pressure sensor, both operating at 500 C. This demonstration represents a significant step towards a wireless pressure sensor that can operate at 500 C and confirms the viability of 500 C electronic sensor systems.

  15. The O+ contribution and role on the ring current pressure development for CMEs and CIRs using Van Allen Probes observations

    Science.gov (United States)

    Mouikis, C.; Bingham, S.; Kistler, L. M.; Farrugia, C. J.; Spence, H. E.; Gkioulidou, M.

    2016-12-01

    The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CME's), co-rotating interaction regions (CIR's), high-speed streamers and other structures. The resulting changes in the ring current particle pressure change the global magnetic field, which affects the transport of the radiation belts. In order to determine the field changes during a storm, it is necessary to understand the transport, sources and losses of the particles that contribute to the ring current. The source population of the storm time ring current is the night side plasma sheet. We use Van Allen Probes observations to determine the ring current pressure contribution of the convecting plasma sheet H+ and O+ particles in the storm time development of the ring current. We compare storms that are related to different interplanetary drivers, CMEs and CIRs, as observed at different local times. We find that during the storm main phase most of the ring current pressure in the pre-midnight inner magnetosphere is contributed by particles on open drift paths that cause the development of a strong partial ring current that causes most of the main phase Dst drop. These particles can reach as deep as L 2 and their pressure compares to the local magnetic field pressure as deep as L 3. During the recovery phase, if these particles are not lost at the magnetopause, will become trapped and will contribute to the symmetric ring current. However, the largest difference between the CME and CIR ring current responses during the storm main and early recovery phases is caused by how the 15 - 60 keV O+ responds to these drivers.

  16. Finite element analysis of large elasto-plastic deformation for sealing ring in nuclear pressure vessel

    International Nuclear Information System (INIS)

    Xiao Xuejian; Chen Ruxin

    1995-02-01

    Based on the R. Hills incremental virtual power principle and the elasto-plastic constitution equation for large deformation and by considering physical nonlinear, geometric nonlinear and thermal effects, a plane and axisymmetric finite element equation for thermal large elasto-plastic deformation has been established in the Euler description. The corresponding analysis program ATLEPD has been also complied for thermal large elasto-plastic deformation process of O-ring in RPV. The variations of stress, strain, contact specific pressure, mesh deformation and the aspects of spring back in upsetting and spring back process have been also investigated. Numerical results are fairly consistent with experimental ones. (5 figs., 4 tabs.)

  17. Size determinations, by ultrasonic techniques, of cracks in hydride blisters formed in Zr-2.5 % Nb pressure tubes

    International Nuclear Information System (INIS)

    Trujillo Badillo, Giovanna; Desimone, Carlos; Domizzi, Gladys

    1999-01-01

    Non destructive techniques (NDT) are very useful in the detection of flaws produced in structural components in service. During the service of CANDU nuclear power reactors, it is possible that pressure tubes (PT) may contact calandria tubes (CT). After the PT/CT contact, zirconium hydride blisters may form at the point of contact depending on the concentration of hydrogen/deuterium. Zirconium hydride is brittle and is therefore prone to cracking under stress. Ultrasonic NDT is routinely use during PT in service inspection. In order to be able of detecting cracked blisters, it is of great importance the development of standards to calibrate the employed equipment. On this purpose, hydride blisters were grown, in laboratory, on sections of pressure tube. The cracks in the blisters were detected and measured by ultrasonic techniques. The obtained results were compared with measurements carried out in optic microscope, on successive sections of the samples. The crack tip diffraction technique was found to be the more effective for the mentioned ends. (author)

  18. Development of Automatic Ultrasonic Testing Equipment for Pressure-Retaining Studs and Bolts in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Suh, D. M.; Park, M. H.; Hong, S. S.

    1989-01-01

    Bolting degradation problems in primary coolant pressure boundary applications have become a major concern in the nuclear industry. In the bolts concerned, the failure mechanism was either corrosion wastage(loss of bolt diameter) or stress-corrosion cracking. Here the manual ultrasonic testing of RPV(Reactor Pressure Vessel) and RCP(Reactor Coolant Pump) stud has been performed. But it is difficult to detect indications because examiner can not exactly control the rotation angle and can not distinguish the indication from signals of bolt. In many cases, the critical sizes of damage depth are very small(1-2 mm order). At critical size, the crack tends to propagatecompletly through the bolt under stress, Resulting in total fracture. Automatic stud scanner for studs(bolts) was developed because the precise measurement of bolt diameter is required in this circumstance. By use of this scanner, the rotation angle of probe was exactly controlled and the exposure time of radiations was reduced

  19. Development of the ultrasonic technique for examination of centrifugally-cast stainless steel in pressure piping

    International Nuclear Information System (INIS)

    Jurenka, H.J.

    1983-01-01

    Centrifugally - cast stainless steel (CCSS) are used to manufacture a large variety of components in the nuclear industry. Weldments are also made to join these parts to carbon steel items. These welds are usually made of stainless steel or inconel alloys. CCSS is sophisticated material and justification for its use in critical components is safety and reliability. These steels, as any other materials, need to be inspected to assess their structural integrity. Ultrasonic testing is one of the possible techniques. In some cases it is the only one of the feasible methods for this examination. This mainly concerns components in the primary and auxiliary circuits of nuclear plants. For a long time it has been recognized that CCSS items can be extremely difficult to inspect using ultrasonics. Many attempts in various research laboratories were conducted to improve the testing technique

  20. Improved ultrasonic nondestructive testing of pressure vessels. Annual progress report, August 1, 1975--July 31, 1976

    International Nuclear Information System (INIS)

    Frederick, J.R.; Fairchild, R.C.; Anderson, B.H.

    1977-07-01

    A synthetic aperture focusing technique for ultrasonic testing (SAFT UT) is described. The technique employs a single scanned transducer operating in pulse-echo mode with digital data acquisition and synthetic aperture post-processing to provide high lateral and longitudinal resolution. The extension of previously developed algorithms to provide volumetric processing and display is described. The design of a refreshed grey-scale display to provide interactive display of SAFT UT data is described

  1. Ultrasonic testing of large blocks for prestressed cast iron pressure vessels

    International Nuclear Information System (INIS)

    Stelling, H.A.

    1979-01-01

    Ultrasonic tests were made on plate specimen and large blocks of perlit cast iron with lamellar graphite. Aims of the investigations were the control of material porperties, the flaw detection and flaw classification. The material properties were classified by sound velocity and attenuation measurements. Flaw detection and flaw size estimation methods were modified with regard to the acoustic properties, the microstructure and the reflectivity of typical flaws in castings. Special localisation and flaw size estimation techniques are discussed. (orig.)

  2. An Innovative 3D Ultrasonic Actuator with Multidegree of Freedom for Machine Vision and Robot Guidance Industrial Applications Using a Single Vibration Ring Transducer

    Directory of Open Access Journals (Sweden)

    M. Shafik

    2013-07-01

    Full Text Available This paper presents an innovative 3D piezoelectric ultrasonic actuator using a single flexural vibration ring transducer, for machine vision and robot guidance industrial applications. The proposed actuator is principally aiming to overcome the visual spotlight focus angle of digital visual data capture transducer, digital cameras and enhance the machine vision system ability to perceive and move in 3D. The actuator Design, structures, working principles and finite element analysis are discussed in this paper. A prototype of the actuator was fabricated. Experimental tests and measurements showed the ability of the developed prototype to provide 3D motions of Multidegree of freedom, with typical speed of movement equal to 35 revolutions per minute, a resolution of less than 5μm and maximum load of 3.5 Newton. These initial characteristics illustrate, the potential of the developed 3D micro actuator to gear the spotlight focus angle issue of digital visual data capture transducers and possible improvement that such technology could bring to the machine vision and robot guidance industrial applications.

  3. GASP. V. Ram-pressure stripping of a ring Hoag's-like galaxy in a massive cluster

    Science.gov (United States)

    Moretti, A.; Poggianti, B. M.; Gullieuszik, M.; Mapelli, M.; Jaffé, Y. L.; Fritz, J.; Biviano, A.; Fasano, G.; Bettoni, D.; Vulcani, B.; D'Onofrio, M.

    2018-04-01

    Through an ongoing MUSE program dedicated to study gas removal processes in galaxies (GAs Stripping Phenomena in galaxies with MUSE, GASP), we have obtained deep and wide integral field spectroscopy of the galaxy JO171. This galaxy resembles the Hoag's galaxy, one of the most spectacular examples of ring galaxies, characterized by a completely detached ring of young stars surrounding a central old spheroid. At odds with the isolated Hoag's galaxy, JO171 is part of a dense environment, the cluster Abell 3667, which is causing gas stripping along tentacles. Moreover, its ring counter-rotates with respect to the central spheroid. The joint analysis of the stellar populations and the gas/stellar kinematics shows that the origin of the ring was not due to an internal mechanism, but was related to a gas accretion event that happened in the distant past, prior to accretion on to Abell 3667, most probably within a filament. More recently, since infall in the cluster, the gas in the ring has been stripped by ram pressure, causing the quenching of star formation in the stripped half of the ring. This is the first observed case of ram-pressure stripping in action in a ring galaxy, and MUSE observations are able to reveal both of the events (accretion and stripping) that caused dramatic transformations in this galaxy.

  4. Experimental study and theoretical interpretation of saturation effect on ultrasonic velocity in tight sandstones under different pressure conditions

    Science.gov (United States)

    Li, Dongqing; Wei, Jianxin; Di, Bangrang; Ding, Pinbo; Huang, Shiqi; Shuai, Da

    2018-03-01

    Understanding the influence of lithology, porosity, permeability, pore structure, fluid content and fluid distribution on the elastic wave properties of porous rocks is of great significance for seismic exploration. However, unlike conventional sandstones, the petrophysical characteristics of tight sandstones are more complex and less understood. To address this problem, we measured ultrasonic velocity in partially saturated tight sandstones under different effective pressures. A new model is proposed, combining the Mavko-Jizba-Gurevich relations and the White model. The proposed model can satisfactorily simulate and explain the saturation dependence and pressure dependence of velocity in tight sandstones. Under low effective pressure, the relationship of P-wave velocity to saturation is pre-dominantly attributed to local (pore scale) fluid flow and inhomogeneous pore-fluid distribution (large scale). At higher effective pressure, local fluid flow gradually decreases, and P-wave velocity gradually shifts from uniform saturation towards patchy saturation. We also find that shear modulus is more sensitive to saturation at low effective pressures. The new model includes wetting ratio, an adjustable parameter that is closely related to the relationship between shear modulus and saturation.

  5. Ultimate strength analysis of ring-stiffened cylinders subjected to hydrostatic pressure

    International Nuclear Information System (INIS)

    Park, Chi Mo

    1990-01-01

    In this study, ultimate strength analysis of ring-stiffened cylinders have been performed, considering the elasto-plastic large deflection. In the elasto-plastic analysis, von Mises yield criteria, the plastic flow theory and the layered approach have been adopted. In order to take into account the follower force effect of the hydrostatic pressure, the incremental load components have been updated at every loading step. As collapse modes, axisymmetric yielding, interframe shell buckling and general buckling are considered, while local buckling of ring-stiffener is not considered. Initial shape imperfection is assumed to be the elastic buckling mode to obtain the lower bound of the ultimate strength. Results of numerical analysis are compared with the experimental results to show the validity of the present approach. It has been drawn that the present numerical results are closely correlated with the experimental results. On the other hand, the effects of initial shape imperfection and condition on the ultimate strength have been investigated. (Author)

  6. Ultrasonic Testing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyeong Jun; Kuk, Jeong Han

    2002-02-15

    This book introduces ultrasonic testing, which tells of outline of ultrasonic testing, principle of ultrasonic testing, prosperities of ultrasonic waves, radiographic test and ultrasonic test, basic theory on ultrasonic testing, mode conversion, transmission and diffraction, ultrasonic flaw detection and probe, standard test piece and reference test piece, like KS(JIS) ASME and ASTM, classification and properties of ultrasonic testing, straight beam method, angle beam method, ASME SEC.V.Art.5 ASTMA 388 and KS B 0817 Korean industrial standard.

  7. First experiments on visualisation of two-phase high pressure and temperature flows using an ultrasonic mesh sensor

    International Nuclear Information System (INIS)

    Melnikov, V.I.; Khokhlov, V.N.; Ivanov, V.V.; Kontelev, V.V.; Zoi, V.R.; Zavinov, A.A.

    2003-01-01

    A novel device for fast visualisation of gas-liquid two-phase flows was developed and tested during loss-off-coolant accident simulations at the thermal hydraulic test facility PSB-VVER, a 1:300 integral model of the VVER-1000. The device is an ultrasonic mesh sensor. It consists of a metallic frame where transmitter and receiver wave-guides are fixed, that form two grids inside the measurement cross section. Ultrasonic pulses are transmitted into the fluid by the 8 wave-guides of the first plane. A second plane of another 8 wave-guides, that cross the ones of the first plane under an angle of 90 deg, serves as receives. The measurement is based on the acoustic conductivity of the two-phase mixture at the locations where the wave-guides cross. The sampling frequency is 250 frames per second. This allows both void fraction measurements and a fast flow visualisation. The sensor is applicable to high pressures and temperatures. All parts and surfaces that are in contact with the fluid are manufactured from stainless steel. During the tests at PSB-VVER the flow pattern in the hot leg of the primary circuit model was visualised for the first time. (orig.)

  8. Phased array concept for the ultrasonic inservice inspection of the spherical bottom of BWR-pressure vessels

    International Nuclear Information System (INIS)

    Brekow, G.; Wuestenberg, H.; Moehrle, W.; Schulz, E.

    1989-01-01

    The spherical bottom of BWR-pressure vessels contains holes for the nozzles of control rods and instrumentation. Up to now the detectable areas for the ultrasonic inspection are the accessible ligaments between the nozzles with an orientation parallel and transverse to the manipulator rails. Some licensing authorities demand an inspection technique capable of reliably detecting significant crack initiation in all critical areas near the cladding of the spherical inner surface. By order and in cooperation with the HEW we have developed a computer controlled equipment with two ultrasonic probes containing four linear arrays and a digitized A-scan storage for documentation and evaluation of inspection results. The manipulator guided probe movement in the paths between the nozzles of the spherical bottom is controlled by a computer program. This program determines for each array system and for each coupling position the beam angle as a function of the variable skewing angle to realize detection conditions suited to possible crack positions at the longitudinal, transverse and diagonal ligaments between the nozzles for control rods and instrumentation. (orig./HP)

  9. Modelling of Outer and Inner Film Oil Pressure for Floating Ring Bearing Clearance in Turbochargers

    International Nuclear Information System (INIS)

    Zhang Hao; Shi Zhanqun; Gu Fengshou; Ball, Andrew

    2011-01-01

    Floating ring bearing is widely used in turbochargers to undertake the extreme condition of high rotating speed and high operating temperature. It is also the most concerned by the designers and users alike due to its high failure rate and high maintenance cost. Any little clearance change may result in oil leakage, which in turn cause blue smoke or black smoke according to leakage types. However, there is no condition monitoring of this bearing because it is almost impossible to measure the clearance especially the inner clearance, in which the inner oil film directly bears the high speed rotation. In stead of measuring clearance directly, this paper has proposed a method that uses film pressure as a measure to monitor the bearing clearance and its variation. A non-linear mathematical model is developed by using Reynolds equations with non-linear oil film pressure. A full description of the outer and inner film is provided along both axial and radial directions. A numerical simulation is immediately carried out. Variable clearance changes are investigated using the mathematical model. Results show the relationship between clearance and film pressure.

  10. Non-linear general instability of ring-stiffened conical shells under external hydrostatic pressure

    International Nuclear Information System (INIS)

    Ross, C T F; Kubelt, C; McLaughlin, I; Etheridge, A; Turner, K; Paraskevaides, D; Little, A P F

    2011-01-01

    The paper presents the experimental results for 15 ring-stiffened circular steel conical shells, which failed by non-linear general instability. The results of these investigations were compared with various theoretical analyses, including an ANSYS eigen buckling analysis and another ANSYS analysis; which involved a step-by-step method until collapse; where both material and geometrical nonlinearity were considered. The investigation also involved an analysis using BS5500 (PD 5500), together with the method of Ross of the University of Portsmouth. The ANSYS eigen buckling analysis tended to overestimate the predicted buckling pressures; whereas the ANSYS nonlinear results compared favourably with the experimental results. The PD5500 analysis was very time consuming and tended to grossly underestimate the experimental buckling pressures and in some cases, overestimate them. In contrast to PD5500 and ANSYS, the design charts of Ross of the University of Portsmouth were the easiest of all these methods to use and generally only slightly underestimated the experimental collapse pressures. The ANSYS analyses gave some excellent graphical displays.

  11. Radial profile of pressure in a storm ring current as a function of D st

    Science.gov (United States)

    Kovtyukh, A. S.

    2010-06-01

    Using satellite data obtained near the equatorial plane during 12 magnetic storms with amplitudes from -61 down to -422 nT, the dependences of maximum in L-profile of pressure ( L m) of the ring current (RC) on the current value of D st are constructed, and their analytical approximations are derived. It is established that function L m( D st ) is steeper on the phase of recovery than during the storm’s main phase. The form of the outer edge of experimental radial profiles of RC pressure is studied, and it is demonstrated to correspond to exponential growth of the total energy of RC particles on a given L shell with decreasing L. It is shown that during the storms’ main phase the ratio of plasma and magnetic field pressures at the RC maximum does not practically depend on the storm strength and L m value. This fact reflects resistance of the Earth’s magnetic field to RC expansion, and testifies that during storms the possibilities of injection to small L are limited for RC particles. During the storms’ recovery phase this ratio quickly increases with increasing L m, which reflects an increased fraction of plasma in the total pressure balance. It is demonstrated that function L m( D st ) is derived for the main phase of storms from the equations of drift motion of RC ions in electrical and magnetic fields, reflecting the dipole character of magnetic field and scale invariance of the pattern of particle convection near the RC maximum. For the recovery phase it is obtained from the Dessler-Parker-Sckopke relationship. The obtained regularities allow one to judge about the radial profile of RC pressure from ground-based magnetic measurements (data on the D st variation).

  12. Phase locked multiple rings in the radiation pressure ion acceleration process

    Science.gov (United States)

    Wan, Y.; Hua, J. F.; Pai, C.-H.; Li, F.; Wu, Y. P.; Lu, W.; Zhang, C. J.; Xu, X. L.; Joshi, C.; Mori, W. B.

    2018-04-01

    Laser contrast plays a crucial role for obtaining high quality ion beams in the radiation pressure ion acceleration (RPA) process. Through one- and two-dimensional particle-in-cell (PIC) simulations, we show that a plasma with a bi-peak density profile can be produced from a thin foil on the effects of a picosecond prepulse, and it can then lead to distinctive modulations in the ion phase space (phase locked double rings) when the main pulse interacts with the target. These fascinating ion dynamics are mainly due to the trapping effect from the ponderomotive potential well of a formed moving standing wave (i.e. the interference between the incoming pulse and the pulse reflected by a slowly moving surface) at nodes, quite different from the standard RPA process. A theoretical model is derived to explain the underlying mechanism, and good agreements have been achieved with PIC simulations.

  13. Continuous ultrasonic waves to detect steam bubbles in water under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Hulshof, H J.M.; Schurink, F

    1985-01-01

    Steam in the recirculation circuit of boilers may lead to unacceptable high thermal loads on the evaporator tubes. The ability to detect steam in the recirculation circuit during process transients is therefore important. A simple detector using continuous ultrasonic waves and able to detect bubbles in water contained in steel tubes is described in this paper. The variation of the transmitted wave caused by the bubbles was determined by demodulation. The results have met the objectives set for cold water with air bubbles. A clear indication of the presence of steam bubbles was found in fast-flowing hot water in a steel tube with a diameter of 60 mm. A change in the low-frequency region of the modulation was the only indication of the presence of steam bubbles in the large-diameter downcomer of the water-separator drum of a boiler in an electrical power plant. Possible causes of the differences in the results obtained are discussed on the basis of differences in bubble sizes and in focusing and reflection of the ultrasonic waves. (orig.). 11 refs.; 10 figs.

  14. Continuous ultrasonic waves to detect steam bubbles in water under high pressure

    International Nuclear Information System (INIS)

    Hulshof, H.J.M.; Schurink, F.

    1985-01-01

    Steam in the recirculation circuit of boilers may lead to unacceptable high thermal loads on the evaporator tubes. The ability to detect steam in the recirculation circuit during process transients is therefore important. A simple detector using continuous ultrasonic waves and able to detect bubbles in water contained in steel tubes is described in this paper. The variation of the transmitted wave caused by the bubbles was determined by demodulation. The results have met the objectives set for cold water with air bubbles. A clear indication of the presence of steam bubbles was found in fast-flowing hot water in a steel tube with a diameter of 60 mm. A change in the low-frequency region of the modulation was the only indication of the presence of steam bubbles in the large-diameter downcomer of the water-separator drum of a boiler in an electrical power plant. Possible causes of the differences in the results obtained are discussed on the basis of differences in bubble sizes and in focusing and reflection of the ultrasonic waves. (orig.)

  15. Development of an ultrasonic flow and temperature measurement system for pressurized water reactors

    International Nuclear Information System (INIS)

    James, R.W.; Lubnow, T.; Baumgart, G.; Ravetti, D.

    1996-01-01

    In U.S. nuclear plants, primary coolant flow and reactor thermal power are calculated from a measurement of feedwater flow to the steam generator combined with knowledge of steam generator heat transfer characteristics nd measurement of hot leg temperature by resistance temperature detectors (RTDs). The calculation of plant thermal output is complicated by an indirect measurement of primary coolant mass flow rate and thermal streaming in the region where hot leg temperature is typically measured. Uncertainty in the thermal output calculation results from uncertainties in steam generator characteristics, in the hot leg temperature due to thermal streaming, and in fouling of venturi nozzles used for feedwater flow measurement. This in turn leads to operation of power plants ar lower levels of efficiency. The Electric Power Research Institute (EPRI) has on ongoing project to develop a prototype system to directly measure primary coolant flow rate and bulk average temperature using ultrasonic transducers externally mounted on the pipe. The topic of this paper is a summary of the project experience in developing this system. The technology being developed in this project is based in part upon previously existing ultrasonic feedwater flow measurement technology developed by MPR Associates and Caldon, Inc EPRI is a non-profit company performing research for U.S. and international electric power utilities. (authors)

  16. Modifications to the application of pressure to a quarter of the circumference of panel rings (tests 54 and 55)

    Energy Technology Data Exchange (ETDEWEB)

    Van Duyse, H [INIEX

    1978-01-01

    Tests 54 and 55 were carried out on rings made up of the usual type of panel. Test 54 involved panels manufactured at Zolder and Test 55 involved those manufactured at Beringen. Both types of ring are 20 cm thick, 64 cm wide and have an internal diameter of 4.20 m. The tests involved application of pressure to one quarter of the circumference, the remainder of the ring being subject to restraint against the steel testing frame. Timber chocks were inserted between the ring and the frame. The reinforcements tested were those used with the normal type of panel. An account of deformation of the ring, cracking of the panels, and deformation of the concrete is given. Tables and figures summarizing the results achieved are included. Maximum load prior to breaking was 292 t in the case of the Zolder ring and 293 t in the case of the Beringen ring; initial cracking occurred at 35 and 30 t, respectively. (In French and in Dutch)

  17. Contact behavior analysis of elastomeric x-ring under uniform squeeze rate and internal pressure before and after forcing-out using the photoelastic experimental hybrid method

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Alunda Ouma [Dedan Kimathi University of Technology, Nyeri (Kenya); Hawong, Jai Sug; Dong, Bai [Yeungnam University, Gyeongsan (Korea, Republic of); Shin, Dong Chul [Koje College, Geoje (Korea, Republic of)

    2015-05-15

    Many different types of elastomeric rings have been developed to suit various needs in industry. The X-ring was introduced as a result of the limitations of O-rings that twist, especially during dynamic application. A better understanding of the behavior and the stress distribution of the X-ring under a uniform squeeze rate and internal pressure is needed. We analyzed the contact stresses and internal stresses developed in an X-ring before and after forcing-out by using the photoelastic experimental hybrid method, ascertained the packing ability of an X-ring, and studied the failure criterion of an X-ring under uniform squeeze rate and internal pressure. Forcing-out in the X-ring occurred when the internal pressure was 3.92 MPa. After forcing-out, at an internal pressure of 5.88 MPa, the two lobes on the upper contact surface merged one contact side of the upper side immensely. Even after extrusion of the X-ring, the X-ring can be used to effectively contain the fluid. This is because the effects of extrusion on the X-ring affected the stress distribution of only two lobes close to the assembly gap and the two lobes are merge into one lobe. In addition, our experimental results show that the maximum shear failure criterion is suitable for the prediction of failure in X-ring seals.

  18. HISTRAP [Heavy Ion Storage Ring for Atomic Physics] vacuum test stand for pressures of 10-12 Torr

    International Nuclear Information System (INIS)

    Johnson, J.W.; Atkins, W.H.; Dowling, D.T.; McConnell, J.W.; Milner, W.T.; Olsen, D.K.

    1988-01-01

    HISTRAP, Heavy Ion Storage Ring for Atomic Physics, is a proposed synchrotron/cooler/storage ring accelerator optimized for advanced atomic physics research. The ring has a circumference of 46.8 m, a bore diameter of about 15 cm, and requires a vacuum of 10 -12 Torr in order to decelerate highly-charged very-heavy ions down to low energies. To be able to test components and procedures to achieve this pressure, a test stand approximately modeling one-sixteenth of the ring vacuum chamber has been built. The 3.5-m-long test stand has been fabricated from 10-cm-diameter components, with 316LN stainless steel flanges. Prior to assembly, these components were vacuum fired at 950/degree/C at a pressure of 10 -4 Torr. The test stand is bakeable in situ at 300/degree/C. Pumping is achieved with two 750-L/s titanium sublimator pumps and one 60-L/s ion pump. Pressure is measured with two extractor ion gauges and a 10 -14 PP RGA. The roughing for the test stand consists of cryosorption pumps followed by a cryopump. A pressure of 4 x 10 -12 Torr has been achieved. 7 refs., 5 figs

  19. Stress State of Elastic Thick-Walled Ring With Self-Balanced Pressures Distributed on Its Internal and External Borders

    Directory of Open Access Journals (Sweden)

    Kravchuk Aleksandr Stepanovich

    2015-10-01

    Full Text Available For the first time with the help of the theory of analytic functions and Kolosov-Muskhelishvili formulas the problem of the two-dimensional theory of elasticity for a thickwalled ring with the uneven pressures, acting on its borders, was solved. The pressure on the inner and outer boundaries is represented by Fourier series. The authors represent the two complex functions which solve boundary problem in the form of Laurent series. The logarithmic terms in these series are absent because the boundary problem has the self-balancing loads on each boundary of ring. The coefficients in the Laurent series are calculated by the boundary conditions. Firstly, the equations were obtained in the general form. But the hypothesis about even distributions of pressures at borders of ring was used for constructing an example. It leads to the fact that all coefficients of analytic functions represented in Laurent series have to be only real. As a solving example, the representation of pressures in equivalent hypotrochoids was used. The application of the computer algebra system Mathematica greatly simplifies the calculation of the distribution of stresses and displacements in ring. It does not require manual formal separation of real and imaginary parts in terms of Kolosov-Muskhelishvili to display the distribution of the physical parameters. It separates them only for calculated numbers with the help of built-in functions.

  20. Observation of Cherenkov rings using a low-pressure parallel-plate chamber and a solid cesium-iodide photocathode

    International Nuclear Information System (INIS)

    Lockyer, N.S.; Millan, J.E.; Lu, C.; McDonald, K.T.; Lopez, A.

    1993-01-01

    We have observed Cherenkov rings from minimum-ionizing particles using a low-pressure, parallel-plate pad-chamber with a cesium-iodide solid photocathode. This detector is blind to minimum-ionizing particles, and sensitive to Cherenkov photons of wavelengths 170-210 nm. An average of 5 photoelectrons per Cherenkov ring were detected using a 2-cm-thick radiator of liquid C 6 F 14 . This paper reports on the chamber construction, photocathode preparation and testbeam results. (orig.)

  1. Simultaneous in vivo imaging of diffuse optical reflectance, optoacoustic pressure and ultrasonic scattering (Conference Presentation)

    Science.gov (United States)

    Subochev, Pavel V.; Orlova, Anna G.; Turchin, Ilya V.

    2017-03-01

    We will present reflection-mode bioimaging system providing complementary optical, photoacsoutic and acoustic measurements by acoustic detector after each laser pulse with 2kHz repetition rate. The photons absorbed within the biological tissue provide optoacoustic (OA) signals, the photons absorbed by the external electrode of a detector provide the measurable diffuse reflectance (DR) from the sample and the probing ultrasonic (US) pulse. To demonstrate the in vivo capabilities of the system we performed complementary DR/OA/US imaging of small laboratory animals and human palm with 3.5mm/50μm/35μm lateral resolution at up to 3 mm diagnostic depth. Functional OA and DR imaging demonstrated the levels of tissue vascularization and blood supply. Structural US imaging was essential for understanding the position of vessels and zones with different perfusion. Before BiOS-2017 we plan to accomplish more in vivo experiments validating the developed triple-modality system as diagnostic tool to detect vascularization as well as mechanisms of vascular changes when monitoring response to therapy.

  2. Remote ultrasonic characterisation of an irradiated pressure tube from RAPS-II

    Energy Technology Data Exchange (ETDEWEB)

    Gangotra, S; Muralidhar, S; Raut, S D; Ouseph, P M; Ghosh, J K; Sahoo, K C [Bhabha Atomic Research Centre, Bombay (India). Radiometallurgy Div.

    1994-12-31

    The Rajasthan Atomic Power Station Unit-2 (RAPS-2) has reached a stage of operation where the contacting pressure tubes are suspect to failure as a result of irradiation creep and displacement of the garter springs, the hot pressure tube coming in contact with the cold calandria tube. To study and assess the safety of these pressure tubes, two channels believed to be in contact with the calandria tubes, have been removed from the reactor for detailed full length post irradiation examination. Some of the test results are presented. 2 refs., 3 figs., 1 tab.

  3. Stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  4. Non-Invasive Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume

    Science.gov (United States)

    2001-10-01

    Libraria, Padoue (Italia) 53 37. Guinduiz G, Viernstein LW (1979). Intracranial pressure in the normal monkey while awake and asleep. J Neurosurg 51, 206...cerebral microcirculation of awake rabbits. Heart Circ Physiol 23, H67-H71 46. Hyndman BW, Kitney RI, Sayers BM (1971). Spontaneous rhythms in...intracranial pressure monitoring. Exclusion criteria: patients with wounds, scars or a craniotomy overlying the optimal window for transintracranial

  5. The multi-layered ring under parabolic distribution of radial stresses combined with uniform internal and external pressure

    Directory of Open Access Journals (Sweden)

    Christos F. Markides

    2017-04-01

    Full Text Available A recently introduced solution for the stress- and displacement-fields, developed in a multi-layered circular ring, composed of a finite number of linearly elastic concentric layers, subjected to a parabolic distribution of ra-dial stresses, is here extended to encompass a more general loading scheme, closer to actual conditions. The loading scheme includes, besides the para¬-bolic radial stresses, a combination of uniform pressures acting along the outer- and inner- most boundaries of the layered ring. The analytic solution of the problem is achieved by adopting Savin’s pioneering approach for an infinite plate with a hole strengthened by rings. Taking advantage of the results provided by the ana¬lytic solution, a numerical model, simulating the configuration of a three-layered ring (quite commonly encountered in practic¬al applications is validated. The numerical model is then used for a parametric analysis enlightening some crucial aspects of the overall response of the ring.

  6. Application of ultrasonic testing technique to detect gas accumulation in important pipings for pressurized water reactors safety

    Energy Technology Data Exchange (ETDEWEB)

    Fushimi, Yasuyuki [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2002-09-01

    Since 1988, the USNRC has pointed out that gas-binding events might occur at high head safety injection (HHSI) pumps of pressurized water reactors (PWRs). In Japanese PWR plants, corrective actions were taken in response to gas-binding events that occurred on HHSI pumps in the USA, so no gas accumulation event has been reported so far. However, when venting frequency is prolonged with operating cycle extension, the probability of gas accumulation in pipings may increase as in the USA. The purpose of this study was to establish a technique to identify gas accumulation and to measure the gas volume accurately. Taking dominant causes of the gas-binding events in the USA into consideration, we pointed out the following sections in the Japanese PWRs where gas srtipping and/or gas accumulation might occur: residual heat removal system pipings and charging/safety injection pump minimum flow line. Then an ultrasonic testing technique, adopted to identify gas accumulation in the USA, was applied to those sections of the typical Japanese PWR. Consequently, no gas accumulation was found in those pipings. (author)

  7. Comparison of positive-pressure, passive ultrasonic, and laser-activated irrigations on smear-layer removal from the root canal surface.

    Science.gov (United States)

    Sahar-Helft, Sharonit; Sarp, Ayşe Sena Kabaş; Stabholtz, Adam; Gutkin, Vitaly; Redenski, Idan; Steinberg, Doron

    2015-03-01

    The purpose of this study was to compare the efficacy of three irrigation techniques for smear-layer removal with 17% EDTA. Cleaning and shaping the root canal system during endodontic treatment produces a smear layer and hard tissue debris. Three irrigation techniques were tested for solution infiltration of this layer: positive-pressure irrigation, passive ultrasonic irrigation, and laser-activated irrigation. Sixty extracted teeth were divided into six equal groups; 17% EDTA was used for 60 sec irrigation of five of the groups. The groups were as follows: Group 1, treated only with ProTaper™ F3 Ni-Ti files; Group 2, positive-pressure irrigation, with a syringe; Group 3, passive ultrasonic irrigation, inserted 1 mm short of the working length; Group 4, passive ultrasonic irrigation, inserted in the upper coronal third of the root; Group 5, Er:YAG laser-activated irrigation, inserted 1 mm short of the working length; and Group 6, Er:YAG laser-activated irrigation, inserted in the upper coronal third of the root. Scanning electron microscopy showed that the smear layer is removed most efficiently using laser-activated irrigation at low energy with 17% EDTA, inserted either at the working length or only in the coronal upper third of the root. Amounts of Ca, P, and O were not significantly different on all treated dentin surfaces. Smear-layer removal was most effective when the root canals were irrigated using Er:YAG laser at low energy with 17% EDTA solution. Interestingly, removal of the smear layer along the entire canal was similar when the laser was inserted in the upper coronal third and at 1 mm short of the working length of the root canal. This effect was not observed with the ultrasonic and positive-pressure techniques.

  8. Ultrasonic decontamination robot

    International Nuclear Information System (INIS)

    Patenaude, R.S.

    1984-01-01

    An ultrasonic decontamination robot removes radioactive contamination from the internal surface of the inlet and outlet headers, divider plate, tube sheet, and lower portions of tubes of a nuclear power plant steam generator. A programmable microprocessor controller guides the movement of a robotic arm mounted in the header manway. An ultrasonic transducer having a solvent delivery subsystem through which ultrasonic action is achieved is moved by the arm over the surfaces. A solvent recovery suction tube is positioned within the header to remove solvent therefrom while avoiding interference with the main robotic arm. The solvent composition, temperature, pressure, viscosity, and purity are controlled to optimize the ultrasonic scrubbing action. The ultrasonic transducer is controlled at a power density, frequency, and on-off mode cycle such as to optimize scrubbing action within the range of transducer-to-surface distance and solvent layer thickness selected for the particular conditions encountered. Both solvent and transducer control actions are optimized by the programmable microprocessor. (author)

  9. High-Pressure Hot-Gas Self-Acting Floating Ring Shaft Seal for Liquid Rocket Turbopumps. [tapered bore seals

    Science.gov (United States)

    Burcham, R. E.; Diamond, W. A.

    1980-01-01

    Design analysis, detail design, fabrication, and experimental evaluation was performed on two self acting floating ring shaft seals for a rocket engine turbopump high pressure 24132500 n/sq m (3500 psig) hot gas 533 K 9500 F) high speed 3142 rad/sec (30000 rmp) turbine. The initial design used Rayleigh step hydrodynamic lift pads to assist in centering the seal ring with minimum rubbing contact. The final design used a convergent tapered bore to provide hydrostatic centering force. The Rayleigh step design was tested for 107 starts and 4.52 hours total. The leakage was satisfactory; however, the design was not acceptable due to excessive wear caused by inadequate centering force and failure of the sealing dam caused by erosion damage. The tapered bore design was tested for 370 starts and 15.93 hours total. Satisfactory performance for the required life of 7.5 hours per seal was successfully demonstrated.

  10. Method of producing the arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels of nuclear reactors

    International Nuclear Information System (INIS)

    Kumpf, H.

    1976-01-01

    In producing arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels for nuclear power plants, it is of advantage to manufacture these directly on the construction site. According to the invention the, at first level, diaphragm ring is put on the predetermined place, sectionally pressed against and shaped by a shaping tool - with a profiled supporting ring as a counter-acting tool - and afterwards welded together with the annular wall sections of the large container along the shaped parts. The manufacture of single and double configurations of diaphragm rings is described. It is of advantage if shaping and mounting position coincide. (UWI) [de

  11. Ultrasonic study of the temperature and hydrostatic-pressure dependences of the elastic properties of polycrystalline cementite (Fe{sub 3}C)

    Energy Technology Data Exchange (ETDEWEB)

    Dodd, S.P.; Saunders, G.A. [Department of Physics, University of Bath, Bath BA2 7AY (United Kingdom); Cankurtaran, M. [Hacettepe University, Department of Physics, Beytepe, 06532 Ankara (Turkey); James, B. [DSTL-Chertsey (Armour Group), Chobham Lane, Chertsey, Surrey KT16 OEE (United Kingdom); Acet, M. [Tieftemperaturephysik, Universitaet Duisburg, 47048 Duisburg (Germany)

    2003-08-01

    Pulse-echo-overlap measurements of ultrasonic wave velocity have been used to determine the dependences of the elastic stiffness moduli of polycrystalline cementite (Fe{sub 3}C) on temperature in the range 75-295 K and hydrostatic pressure up to 0.1 GPa at room temperature. The longitudinal stiffness (C{sub L}) and adiabatic bulk modulus (B{sup S}) stiffen, while the shear stiffness ({mu}) and Young's modulus (E) soften with decreasing temperature. The ultrasonic velocities increase approximately linearly with pressure, much more steeply for the longitudinal than the shear mode. The values obtained at 295 K for the hydrostatic-pressure derivatives ({partial_derivative}C{sub L}/{partial_derivative}P){sub P=0}, ({partial_derivative}{mu}/{partial_derivative}P){sub P=0} and ({partial_derivative}B{sup S}/{partial_derivative}P){sub P=0} of cementite are 7.9{+-} 1.7, 1.4{+-}0.1 and 6.1{+-}1.7, respectively: the zone-centre acoustic phonons stiffen under pressure. The longitudinal ({gamma}{sub L}), shear ({gamma}{sub S}) and mean ({gamma}{sup el}) acoustic-mode Grueneisen parameters of cementite are positive; {gamma}{sub S} is markedly smaller than {gamma}{sub L} indicating that the shear acoustic modes are less anharmonic than the longitudinal modes. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  12. Ultrasonic signature

    International Nuclear Information System (INIS)

    Borloo, E.; Crutzen, S.

    1974-12-01

    The unique and tamperproof identification technique developed at Ispra is based on ultrasonic Non-Destructive-Techniques. Reading fingerprints with ultrasonic requires high reproducibility of standard apparatus and transducers. The present report gives an exhaustive description of the ultrasonic technique developed for identification purposes. Different applications of the method are described

  13. Ultrasonic testing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin [Sungkwunkwan Univ., Seoul (Korea, Republic of); Jeong, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of)

    2004-02-15

    For the proper performance of ultrasonic testing of steel welded joints, and anisotropic material it is necessary to have sound understanding on the underlying physics. To provide such an understanding, it is beneficial to have simulation tools for ultrasonic testing. In order to address such a need, we develop effective approaches to simulate angle beam ultrasonic testing with a personal computer. The simulation is performed using ultrasonic measurement models based on the computationally efficient multi-Gaussian beams. This reach will describe the developed ultrasonic testing models together with the experimental verification of their accuracy.

  14. Improvement of vacuum pressure in the annular-ring coupled structures for the J-PARC linac

    International Nuclear Information System (INIS)

    Ao, Hiroyuki; Nemoto, Yasuo; Oozone, Akira; Tamura, Jun

    2015-01-01

    The accelerating cavities of the J-PARC linac, additionally comprising an annular-ring-coupled structure (ACS), went into operation in 2014. To further improve the vacuum pressure of the ACS, an additional nonevaporable getter (NEG) pump was designed so that it could be installed independent of the vacuum chamber of the ACS cavity. We confirmed that the NEG pump can be appropriately activated by using a small pumping station and that purging with noble gases reduces the saturation of the NEG surface. In the evacuation test of the prototype ACS cavity with the NEG pump, the partial pressure of H_2 and the total pressure were reduced from 4.8 × 10"-"7 and 6.8 × 10"-"7 Pa to 2.5 × 10"-"7 and 4.5 × 10"-"7 Pa, respectively. The additional NEG pump will be installed in the ACS cavity in the fall of 2014, after which any decrease in pressure and NEG-pump lifetime will be confirmed by long-term-operation experiments. (author)

  15. Effectiveness of Sealed Double-Ring Infiltrometers trademark and effects of changes in atmospheric pressure on hydraulic conductivity

    International Nuclear Information System (INIS)

    McMullin, S.R.

    1994-01-01

    The Savannah River Site is currently evaluating some 40 hazardous and radioactive-waste sites for remediation. Among the remedial alternatives considered is closure using a kaolin clay cap. The hydraulic conductivity suggested by the US Environmental Protection Agency is 1.0 x 10 -7 cm/sec. One instrument to measure this value is the Sealed Double-Ring Infiltrometer trademark (SDRI). Six SDRI were recently installed on a kaolin test cap. Test results demonstrated uniform performance of these instruments. However, the test data showed as much as an order of magnitude of variation over time. This variation is attributed to both internal structural heterogeneity and variable external boundary conditions. The internal heterogeneity is caused by construction variability within a specified range of moisture and density. The external influences considered are temperature and barometric pressure. Temperature was discharged as a source of heterogeneity because of a lack of correlation with test data and a negligible impact from the range of variability. However, a direct correlation was found between changes in barometric pressure and hydraulic conductivity. This correlation is most pronounced when pressure changes occur over a short period of time. Additionally, this correlation is related to a single soil layer. When the wetting front passes into a more porous foundation layer, the correlation with pressure changes disappears. Conclusions are that the SDRI performs adequately, with good repeatability of results. The duration of test is critical to assure a statistically valid data set. Data spikes resulting from pressure changes should be identified, and professional judgment used to determine the representative hydraulic conductivity. Further evaluation is recommended to determine the impact of pressure change on the actual hydraulic conductivity

  16. Ultrasonic measurements at elevated pressures (9 GPa) to determine Poisson's ratio and other elastic moduli of NaCl and NaF

    International Nuclear Information System (INIS)

    Morris, C.E.; Jamieson, J.C.; Yarger, F.L.

    1976-01-01

    Transit times of longitudinal and transverse ultrasonic waves were measured simultaneously in NaCl and NaF as a function of ''quasihydrostatic'' pressure to 9 GPa. The dimensionless ratio of these transit times yields directly the ratio of the longitudinal to shear velocity. This velocity ratio is independent of sample length. Using third-order elasticity theory a correction for a probable superimposed uniaxial stress component may be made. When done, this allows the direct determination of Poisson's ratio for each pressure. Shock-wave data are used to obtain other elastic moduli and velocities of shear and longitudinal waves. Apparatus for making these measurements is described and data for NaCl and NaF are presented

  17. Ultrasonic evaluation of end cap weld joints of fuel elements of pressurized heavy water reactors using signal analysis methods

    International Nuclear Information System (INIS)

    Raj, B.; Thavasimuthu, M.; Subramanian, C.V.; Kalyanasundaram, P.; Rajagopalan, C.

    1992-01-01

    This paper describes the application of ultrasonic digital signal analysis for the detection of fine defects of the order of 10% or lower of wall thickness (WT) of 370 microns in the resistance welded end cap-cladding tube joints of fuel elements used in Pressurised Heavy Water Reactors (PHWR s). The results obtained for the detection of such defects, have confirmed the sensitivity and reliability of this approach, and were further validated by destructive metallography. (author)

  18. Using ultrasonic measurements and a two-phase composite model to assess radiation damage in reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Wang, J.A.

    1996-01-01

    Ultrasonic methods used in the study of radiation damage and recovery in single crystals appear to also be useful for similar studies on polycrystalline alloys. Ultrasonic methods have demonstrated a sensitivity to radiation damage as affected by neutron fluence, irradiation temperature, large changes in composition, and possibly, as well, by neutron energy spectrum. On the microstructure defect evolution, only the residual defects created through the radiation event will contribute to the final macroscopic material property change. From a microstructure point, it is generally accepted that radiation hardening and embrittlement in metals are caused by clusters of vacancies, interstitial, and solute atoms that impede the motion of slip dislocations. Although vacancy-type defects are a major contributor to the material hardening, they also indicate the presence of other interstitial defects. Thus the total volume change of vacancy-type defects before and after irradiation can serve as a direct index to the final material property changes. The volume change of the vacancy-type defects can be determined by utilizing the two -phase composite model (matrix and void-type inclusion) to interpret wave velocities of baseline and irradiated specimens that are obtained from the ultrasonic wave experiment. This is a relatively economic and straightforward procedure. The correlation of the volume change of the vacancy-type defects with the existing destructive mechanical test results may play an important role in the future for the prediction of the radiation embrittlement and remaining plant lifetime, especially for the older plants on the verge of exhausting all the available mechanical test specimens loaded in the surveillance capsules. The above hypothesis was supported by the limited irradiated data analyzed and presented in his paper. The proposed ultrasonic methodology also has a potential application to assess creep damage in fossil power plants

  19. A diffusive atmospheric pressure glow discharge in a coaxial pin-to-ring gap with a transverse magnetic field

    Directory of Open Access Journals (Sweden)

    YongSheng Wang

    2017-09-01

    Full Text Available Atmospheric pressure glow discharge (APGD has been widely used in the industrial field. The industrial applications are based on achieving stable and diffusive APGD in a relatively large space. The existing sources only achieved stable and diffusive APGD between a short inter-electrode distance within 5 millimeters. In this paper, the effect of a transverse stationary magnetic field on the diffusion of filamentary APGD was studied in a pin-to-ring coaxial gap. The APGD was driven by a high-voltage resonant power supply, and the stationary magnetic field was supplied by a permanent magnet. The stable and diffusive APGD was achieved in the circular area, which diameter was 20 millimeters. The experimental results revealed that more collision ionization occurred and the plasma was distributed diffusively in the discharge gap by applying the external transverse magnetic field. Besides, it is likely to obtain more stable and diffusive APGD in the coaxial pin-to-ring discharge gap when adjusting the input voltage, transverse magnetic flux density and resonant frequency of the power supply.

  20. Ultrasonic physics

    CERN Document Server

    Richardson, E G

    1962-01-01

    Ultrasonic Physics, Second Edition, provides an introduction to the fundamental principles of ultrasonic physics. The book opens with a discussion of the sources of ultrasound. This is followed by separate chapters on the properties and detection of ultrasonic radiation; measurement of propagation constants, i.e., the velocity and absorption, of ultrasound; ultrasound propagation in gases, liquids, and solids; and ultrasound propagation in aerosols, suspensions, and emulsions. The final chapter covers miscellaneous physical and physico-chemical actions, including dispersion and coagulation of

  1. A study on the shell wall thinning causes identified through experiment, numerical analysis and ultrasonic test of high-pressure feedwater heater

    International Nuclear Information System (INIS)

    Hwang, Kyeong Mo; Woo, Lee; Jin, Tae Eun; Kim, Kyung Hoon

    2008-01-01

    Feedwater heaters of many nuclear power plants have recently experienced severe wall thinning damage, which accelerates as the operation progresses. Several nuclear power plants in Korea have undergone this damage around the impingement baffle - installed downstream of the high-pressure turbine extraction steam line - inside numbers 5A and 5B feedwater heaters. At that point, the extracted steam from the high-pressure turbine consists in the form of two-phase fluid at high temperature, high pressure and high velocity. Since it flows in reverse direction after impinging the impingement baffle, the shell wall of number 5 high-pressure feedwater heater may be affected by flow-accelerated corrosion. This paper describes the comparisons between the numerical analysis results using the FLUENT code and the downscaled experimental data in an effort to determine root causes of the shell wall thinning of the high-pressure feedwater heaters. The numerical analysis and experimental data were also confirmed by the actual wall thickness measured by ultrasonic tests. From the comparison of the results for the local velocity profiles and the wall thinning measurements, the local velocity component only in the y-direction flowing vertically to the shell wall, and not in the x- and z-directions, was analogous to the wall thinning data

  2. Validation results of the pre-service ultrasonic inspections of the Sizewell B pressurizer and steam generators and reactor coolant pump flywheels

    International Nuclear Information System (INIS)

    Conroy, P.J.; Leyland, K.S.

    1995-01-01

    In the UK, concern over the safety issues associated with nuclear power generation resulted in a demand for a public inquiry into the construction and operation of Sizewell ''B'', Britain's first PWR. This public inquiry was additional to the UK's normal licensing process. The onus was placed upon the UK utility, CEGB (now Nuclear Electric plc) to provide evidence to the inquiry to support the case that the plant would be constructed and operated to a sufficiently high standard of safety. Part of the evidence to the inquiry (1) relied upon the ability of ultrasonic inspections to verify that the reactor pressure vessel and other safety critical components (collectively known as IoF components), were free from defects that could threaten structural integrity. At that time, the body of evidence showed that although ultrasonic inspection had the potential to satisfy this requirement, it would be necessary to validate the procedures and key operators used in order to provide assurance that they were adequate. Inspection validation therefore became an integral part of the UK PWR nuclear power program

  3. Pressure optimization of an EC-QCL based cavity ring-down spectroscopy instrument for exhaled NO detection

    Science.gov (United States)

    Zhou, Sheng; Han, Yanling; Li, Bincheng

    2018-02-01

    Nitric oxide (NO) in exhaled breath has gained increasing interest in recent years mainly driven by the clinical need to monitor inflammatory status in respiratory disorders, such as asthma and other pulmonary conditions. Mid-infrared cavity ring-down spectroscopy (CRDS) using an external cavity, widely tunable continuous-wave quantum cascade laser operating at 5.3 µm was employed for NO detection. The detection pressure was reduced in steps to improve the sensitivity, and the optimal pressure was determined to be 15 kPa based on the fitting residual analysis of measured absorption spectra. A detection limit (1σ, or one time of standard deviation) of 0.41 ppb was experimentally achieved for NO detection in human breath under the optimized condition in a total of 60 s acquisition time (2 s per data point). Diurnal measurement session was conducted for exhaled NO. The experimental results indicated that mid-infrared CRDS technique has great potential for various applications in health diagnosis.

  4. Simultaneous effects of hydrostatic pressure and spin–orbit coupling on linear and nonlinear intraband optical absorption coefficients in a GaAs quantum ring

    International Nuclear Information System (INIS)

    Mughnetsyan, V.N.; Manaselyan, A.Kh.; Barseghyan, M.G.; Kirakosyan, A.A.

    2013-01-01

    In this paper the simultaneous effect of hydrostatic pressure and Rashba spin–orbit interaction on intraband linear and nonlinear light absorption has been investigated in cylindrical quantum ring. The one electron energy spectrum has been found using the effective mass approximation and diagonalization procedure. We have found that the Rashba interaction can lead both to the blue- or to the red-shift of the absorption spectrum depending on the transitions character, while the only red-shift is observed due to the hydrostatic pressure. - Highlights: ► The effects of hydrostatic pressure and spin–orbit coupling are investigated for quantum ring. ► The non-linear absorption coefficient is calculated. ► The hydrostatic pressure leads to the decrease in the absorption coefficient. ► Spin–orbit coupling weakens some transitions and strengthens others.

  5. Cavity ring down spectroscopy of CH, CH2, HCO, and H2CO in a premixed flat flame at both atmospheric and sub-atmospheric pressure

    NARCIS (Netherlands)

    Evertsen, R.; Staicu, A.D.; Oijen, van J.A.; Dam, N.J.; Goey, de L.P.H.; Meulen, ter J.J.; Cheauveau, C.; Vovelle, C.

    2003-01-01

    Density distributions of CH, CH2, HCO and H2CO have been measured in a premixed CH4/air flat flame by Cavity Ring Down Spectroscopy (CRDS). At atmospheric pressure problems are encountered due to the narrow spatial distribution of these species. Rotational flame Temperatures have been derived from

  6. Estimate of LOCA-FI plenum pressure uncertainty for a five-ring RELAP5 production reactor model

    International Nuclear Information System (INIS)

    Griggs, D.P.

    1993-03-01

    The RELAP5/MOD2.5 code (RELAP5) is used to perform best-estimate analyses of certain postulated Design Basis Accidents (DBAs) in SRS production reactors. Currently, the most limiting DBA in terms of reactor power level is an instantaneous double-ended guillotine break (DEGB) loss of coolant accident (LOCA). A six-loop RELAP5 K Reactor model is used to analyze the reactor system behavior dozing the Flow Instability (FI) phase of the LOCA, which comprises only the first 5 seconds following the DEGB. The RELAP5 K Reactor model includes tank and plenum nodalizations having five radial rings and six azimuthal sectors. The reactor system analysis provides time-dependent plenum and tank bottom pressures for use as boundary conditions in the FLOWTRAN code, which models a single fuel assembly in detail. RELAP5 also performs the system analysis for the latter phase of the LOCA, denoted the Emergency Cooling System (ECS) phase. Results from the RELAP analysis are used to provide boundary conditions to the FLOWTRAN-TF code, which is an advanced two-phase version of FLOWTRAN. The RELAP5 K Reactor model has been tested for LOCA-FI and Loss-of-Pumping Accident analyses and the results compared with equivalent analyses performed with the TRAC-PF1/MOD1 code (TRAC). An equivalent RELAP5 six-loop, five-ring, six-sector L Reactor model has been benchmarked against qualified single-phase system data from the 1989 L-Area In-Reactor Test Program. The RELAP5 K and L Reactor models have also been subjected to an independent Quality Assurance verification

  7. Ultrasonic unit for line-by-line ultrasonic scanning of bodies

    International Nuclear Information System (INIS)

    Soldner, R.

    1978-01-01

    The ultrasonic unit for medical diagnostics operates by the sectorial scanning principle, which avoids direct coupling of the transducer head to the surface of the body. For this purpose, several transmitter/receiver units (approx. 100) are arranged on a partial ring of a circular arc and the ultrasonic beams, which can be triggered sequentially in time, are directed at a common intersection behind the ultrasonic window of the unit, i.e., outside the unit. A mechanical system is employed to set and adjust the partial ring carrying the transmitter/receiver units. (DG) [de

  8. Ultrasonic inspection

    International Nuclear Information System (INIS)

    Satittada, Gannaga

    1984-01-01

    Ultrasonic inspection is one of the most widely used methods for nondestructive inspection. The beam of high-frequency sound wave, ultrasonic wave, is introduced into the material. It travels through the material with some attendant loss of energy and can be reflected at interfaces. The reflected beam is detected and analyzed. Ultrasonic inspection is used to detect flaws in metal parts as well as in welded, brazed and bonded joints during research work and developing production and service. It is also used to detect and locate porosity, pipe, and flakes. In addition, it can be used for the measurement of metal thickness. Ultrasonic inspection is therefore used for quality control and material inspection in all major industries

  9. Pressure derivatives of elastic moduli of fused quartz to 10 kb

    Science.gov (United States)

    Peselnick, L.; Meister, R.; Wilson, W.H.

    1967-01-01

    Measurements of the longitudinal and shear moduli were made on fused quartz to 10 kb at 24??5??C. The anomalous behavior of the bulk modulus K at low pressure, ???K ???P 0, at higher pressures. The pressure derivative of the rigidity modulus ???G ???P remains constant and negative for the pressure range covered. A 15-kb hydrostatic pressure vessel is described for use with ultrasonic pulse instrumentation for precise measurements of elastic moduli and density changes with pressure. The placing of the transducer outside the pressure medium, and the use of C-ring pressure seals result in ease of operation and simplicity of design. ?? 1967.

  10. Case studies in ultrasonic testing

    International Nuclear Information System (INIS)

    Prasad, V.; Satheesh, C.; Varde, P.V.

    2015-01-01

    Ultrasonic testing is widely used Non Destructive Testing (NDT) method and forms the essential part of In-service inspection programme of nuclear reactors. Main application of ultrasonic testing is for volumetric scanning of weld joints followed by thickness gauging of pipelines and pressure vessels. Research reactor Dhruva has completed the first In Service Inspection programme in which about 325 weld joints have been volumetrically scanned, in addition to thickness gauging of 300 meters of pipe lines of various sizes and about 24 nos of pressure vessels. Ultrasonic testing is also used for level measurements, distance measurements and cleaning and decontamination of tools. Two case studies are brought out in this paper in which ultrasonic testing is used successfully for identification of butterfly valve opening status and extent of choking in pipe lines in Dhruva reactor systems

  11. Ultrasonic mammography

    International Nuclear Information System (INIS)

    Hueneke, B.

    1982-01-01

    608 women are examined by means of ultrasonic mammography during the period of 1 year. 432 patients were examined with the compound method with the U.I. Octoson, a water tank scanner, and 176 patients with the real time method with a directly connected linear-array-scanner. The following results were obtained at the end of the examination period: In the ultrasonic and also in the X-ray mammogram tumour diameters can be determined with an error rate of +- 30%. In the diagnosing of carcinomas, a significant dependence of the exactness on the sice of the tumour is found for the combination of the five methods tested (clinical examination, X-ray mammography, ultrasonic mammography, thermography, cytology). Classifying the individual methods with regard to their exactness, X-ray mammography ranks in front of ultrasonic mammography. Mastopathic changes in the breast can be screened by means of ultrasonic mammography. The structure of the changes can be determined more exactly than with an X-ray picture which is due to the possibility of differentiating solid and cystic structures. In diagnosing fibro-adenomas and establishing diagnoses on young women with dense gland bodies, ultrasonic mammography is superior to radiology both in the ability of screening a finding of a fibro-adenoma (US=88%, X-ray=75%) and in the possibility of classifying it as ''more benign than malignant''. (orig./MG) [de

  12. Irradiation Testing of Ultrasonic Transducers

    International Nuclear Information System (INIS)

    Daw, J.; Rempe, J.; Palmer, J.; Tittmann, B.; Reinhardt, B.; Kohse, G.; Ramuhalli, P.; Montgomery, R.; Chien, H.T.; Villard, J.F.

    2013-06-01

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of numerous parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 10 21 n/cm 2 (E> 0.1 MeV). This test will be an instrumented lead test; and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. By characterizing magnetostrictive and piezoelectric transducer survivability during irradiation, test results will enable the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. (authors)

  13. Ring Theory

    CERN Document Server

    Jara, Pascual; Torrecillas, Blas

    1988-01-01

    The papers in this proceedings volume are selected research papers in different areas of ring theory, including graded rings, differential operator rings, K-theory of noetherian rings, torsion theory, regular rings, cohomology of algebras, local cohomology of noncommutative rings. The book will be important for mathematicians active in research in ring theory.

  14. Ultrasonic neuromodulation

    Science.gov (United States)

    Naor, Omer; Krupa, Steve; Shoham, Shy

    2016-06-01

    Ultrasonic waves can be non-invasively steered and focused into mm-scale regions across the human body and brain, and their application in generating controlled artificial modulation of neuronal activity could therefore potentially have profound implications for neural science and engineering. Ultrasonic neuro-modulation phenomena were experimentally observed and studied for nearly a century, with recent discoveries on direct neural excitation and suppression sparking a new wave of investigations in models ranging from rodents to humans. In this paper we review the physics, engineering and scientific aspects of ultrasonic fields, their control in both space and time, and their effect on neuronal activity, including a survey of both the field’s foundational history and of recent findings. We describe key constraints encountered in this field, as well as key engineering systems developed to surmount them. In closing, the state of the art is discussed, with an emphasis on emerging research and clinical directions.

  15. Ultrasonic flowmeters

    International Nuclear Information System (INIS)

    Wittekind, W.D.

    1979-01-01

    A prototype ultrasonic flowmeter was assembled and tested. The theoretical basis of this prototype ultrasonic flowmeter is reviewed; the equipment requirements for a portable unit are discussed; the individual electronic modules contained in the prototype are described; the operating procedures and configuration are explained; and the data from preliminary calibrations are presented. The calibration data confirm that the prototype operates according to theoretical predictions and can indeed provide nonintrusive flow measurements to predicted accuracies for pipes larger than two inches, under single phase stable flow conditions

  16. Linear and nonlinear optical absorption coefficients in GaAs/Ga1−xAlxAs concentric double quantum rings: Effects of hydrostatic pressure and aluminum concentration

    International Nuclear Information System (INIS)

    Baghramyan, H.M.; Barseghyan, M.G.; Kirakosyan, A.A.; Restrepo, R.L.; Duque, C.A.

    2013-01-01

    The linear and nonlinear intra-band optical absorption coefficients in GaAs/Ga 1−x Al x As two-dimensional concentric double quantum rings are investigated. Taking into account the combined effects of hydrostatic pressure and aluminum concentration the energies of the ground (n=1,l=0) and the first excited state (n=2,l=1) have been found using the effective mass approximation and the transfer matrix formalism. The energies of these states and the corresponding threshold energy of the intra-band optical transitions are examined as a function of hydrostatic pressure and aluminum concentration for different sizes of the structure. We also investigated the dependencies of the linear, nonlinear, and total optical absorption coefficients as functions of the incident photon energy for different values of hydrostatic pressure, aluminum concentration, sizes of the structure, and incident optical intensity. Its is found that the effects of the hydrostatic pressure and the aluminum concentration lead to a shifting of the resonant peaks of the intra-band optical spectrum. - Highlights: ► Linear and nonlinear intra-band absorption in quantum rings. ► Threshold energy strongly depends on the hydrostatic pressure. ► Threshold energy strongly depends on the stoichiometry and sizes of structure. ► Optical absorption is affected by the incident optical intensity.

  17. Storage Rings

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    . Storage rings have instrumentation to monitor the electrical and mechanical systems, and the beam quality. Computers are used to control the operation. Large storage rings have millions of control points from all systems. The time dependent beam intensity I(t) can often be approximated by an exponential function I(t) = I(0) exp(-t/τ) (1) where the decay time τ and, correspondingly, the store time ranges from a few turns to 10 days (ISR). τ can be dominated by a variety of effects including lattice nonlinearities, beam-beam, space charge, intrabeam and Touschek scattering, interaction with the residual gas or target, or the lifetime of the stored particle. In this case, the beam lifetime measurement itself can be the purpose of a storage ring experiment. The main consideration in the design of a storage ring is the preservation of the beam quality over the store length. The beam size and momentum spread can be reduced through cooling, often leading to an increase in the store time. For long store times vacuum considerations are important since the interaction rate of the stored particles with the residual gas molecules is proportional to the pressure, and an ultra-high vacuum system may be needed. Distributed pumping with warm activated NEG surfaces or cold surfaces in machines with superconducting magnets are ways to provide large pumping speeds and achieve low pressures even under conditions with dynamic gas loads. The largest application of storage rings today are synchrotron light sources, of which about 50 exist world wide. In experiments where the beam collides with an internal target or another beam, a storage ring allows to re-use the accelerated beam many times if the interaction with the target is sufficiently small. In hadron collider and ion storage rings store times of many hours or even days are realized, corresponding to up to 1011 turns and thereby target passages. Ref. (3) is the first proposal for a collider storage ring. A number of storage rings

  18. Double acting stirling engine piston ring

    Science.gov (United States)

    Howarth, Roy B.

    1986-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  19. In line inspection of multi-diameter and high-pressure pipelines in Brazil using combined technologies: magnetic flux leakage and ultrasonic testing

    Energy Technology Data Exchange (ETDEWEB)

    Ginten, Markus; Brockhaus, Stephan; Bouaoua, Nourreddine; Klein, Stefan [ROSEN Technology and Research Center, Lingen (Germany); Bruening, Franz [ROSEN Brazil, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The simultaneous use of the magnetic flux leakage (MFL) method and the ultrasonic testing (UT) method on a single in line inspection (ILI) tool has been identified as a versatile and accurate solution for liquid pipelines. The combination of the two methods is complementary to the restrictions of each other. Also, the overall scope of the inspection is enlarged. General wall thinning and largely corroded areas are accurately and reliably scanned with the UT unit, while very detailed information about pitting corrosion is obtained from the MFL measurement. Blind spots of echo loss, as occasionally observed for the UT channels is compensated by the more robust measurement from the MFL sensors. Consequently, this technology has been the method of choice in an in line inspection project of an onshore long distance pipeline in Brazil, facing a variety of corrosion threats. The pipeline consists of several multi-diameter sections of 18/20 inches and 20/22 inches. Furthermore, the high gravity of product in combination with a height profile, an altitude of 1152 m MSL (Mean Sea Level) had to be crossed, leads to a maximum pressure of 220 bar. These boundary conditions had to be considered during the design of the ILI-tool. The paper discusses the experience made so far with the combined technology MFL and UT. The effective use of the inspection tool for the above mentioned pipeline as well as field results from a previous inspection are described. (author)

  20. Examination techniques for non-magnetic rings

    International Nuclear Information System (INIS)

    Metala, M.J.; Kilpatrick, N.L.; Frank, W.W.

    1990-01-01

    Until the introduction of 18Mn18Cr rings a few years ago, most non-magnetic steel rings for generator rotors were made from 18Mn5Cr alloy steel, which is highly susceptible to stress corrosion cracking in the presence of water. This, the latest in a series of papers on the subject of non-magnetic rings by the authors' company, provides a discussion of nondestructive examination of 18Mn5Cr rings for stress corrosion distress. With rings on the rotor, fluorescent penetrant, ultrasonic and special visual techniques are applied. With rings off the rotor, the fluorescent penetrant technique is used, with and without stress enhancement

  1. Reduction of the number of defect signals in pressure vessel welds by a phased array ultrasonic test technology qualified beforehand in a blind test according to PDI specifications

    International Nuclear Information System (INIS)

    Mohr, F.

    2007-01-01

    In German-language countries, ultrasonic testing of reactor pressure vessel welds in the context of recurrent inspection is based on the KTA rules. This test philosophy is based on the recording of all data of a test section and repeated comparison of these data at regular intervals. Each and every change during operation is displayed. There are many components in which no changes are observed over longer periods of time. Optimisation of the test procedure and test periods requires accurate knowledge of the component condition. This necessitates accurate data of available defects. However, current techniques only provide data for comparative analysis on the basis of reflectivity. Data on the length and depth of a relevant defect can only be obtained by qualified sizing techniques. The PDI programme provides exact rules for qualification of techniques for a given application. Using a PDI qualification with personal blind tests for all data evaluators, one obtains a basis for accurate defect dimensioning and thus for optimisation. In cooperation with KKL, IntelligeNDT AREVA in 2006 successfully underwent the PDI qualification process for phased array testing of longitudinal and circumferential welds in reactor pressure vessels. In addition to this qualification, a comparison was made with the results of the conventionally applied, KTA-oriented test procedure. One of the key elements of qualification is the characterisation of defects, i.e. the distinction between relevant and non-relevant data, which will help to reduce the displayed data. The contribution presents the results and experience of the qualification as well as a comparison of standard testing with a tandem function with the results of phased array testing. (orig.)

  2. Research on ultrasonic flow detection techniques for LWR facilities

    International Nuclear Information System (INIS)

    Kimura, Katsumi; Fukuhara, Hiroaki; Hoshimoto, Kenichi; Matsumoto, Shojiro; Yamawaki, Hisashi; Ito, Hideyuki; Uetake, Ichizo

    1986-01-01

    Aiming at establishing the techniques for inspecting the inside of LWR pressure vessels by ultrasonic flaw detection from the outside of the vessels, the development of a probe suitable to the flaw detection in the thick steel plates with stainless steel overlay and the method of its driving, the examination of the ultrasonic characteristics of austenitic stainless steel welded metal used for overlay, and the improvement of the detectability of defects and the accuracy of measuring dimensions by the application of signal processing techniques to ultrasonic flaw detection were attempted. In order to cope with the impedance lowering accompanying the increase of oscillator size, the oscillator was divided into the rings with equal area, and the driving and signal receiving were carried out individually, in this way, the good results were obtained by summing the signals. It was theoretically proved that it is rational to use longitudinal waves for the flaw detection in overlay. It was found that by displaying the results of flaw detection as pictures using a microcomputer, the capability of defect detection was increased. Also by the signal processing combining Fourier transformation and filtering, noise removal and the heightening of the accuracy of measuring dimensions were able to be attained. (Kako, I.)

  3. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis.

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile.

  4. Comparisons of negative pressure wound therapy and ultrasonic debridement for diabetic foot ulcers: a network meta-analysis

    Science.gov (United States)

    Wang, Ruran; Feng, Yanhua; Di, Bo

    2015-01-01

    Objective: a network meta-analysis was performed to compare the strength and weakness of negative pressure wound therapy (NPWT) with ultrasound debridement (UD) as for diabetic foot ulcers (DFU). Methods: PubMed, Ovid EMBASE, Web of Science, Cochrane library databases, and Chinese Biomedical Literature Database were searched till February 2015. Clinical compared studies of negative pressure wound therapy and ultrasound debridement were enrolled. The primary efficacy outcomes included healed ulcers, reduction of ulcer areas and time to closure. Secondary amputation including major and minor amputations was used to assess the safety profile. Results: Out of 715 studies, 32 were selected which enrolled 2880 diabetic patients. The pooled analysis revealed that NPWT including vacuum assisted closure (VAC) and vacuum sealing drainage (VSD) were as efficacious as ultrasound debridement improving healed ulcers, odds ratio, 0.86; 95% CI 0.28 to 2.6 and 1.2; 95% CI 0.38 to 4, respectively. However, both were better to standard wound care in wound healing patients. Compared with the standard wound care treated diabetic foot ulcers, NPWT and UD resulted in a significantly superior efficacy in time to wound closure and decrement in area of wound. No significances were observed between NPWT and UD groups in both indicators. Fewer patients tended to receive amputation in NPWT and UD groups compared to standard wound care group. Conclusions: The results of the network meta-analysis indicated that negative pressure wound therapy was similar to ultrasound debridement for diabetic foot ulcers, but better than standard wound care both in efficacy and safety profile. PMID:26550165

  5. Monitoring localized cracks on under pressure concrete nuclear containment wall using linear and nonlinear ultrasonic coda wave interferometry

    Science.gov (United States)

    Legland, J.-B.; Abraham, O.; Durand, O.; Henault, J.-M.

    2018-04-01

    Civil engineering is constantly demanding new methods for evaluation and non-destructive testing (NDT), particularly to prevent and monitor serious damage to concrete structures. Tn this work, experimental results are presented on the detection and characterization of cracks using nonlinear modulation of coda waves interferometry (NCWT) [1]. This method consists in mixing high-amplitude low-frequency acoustic waves with multi-scattered probe waves (coda) and analyzing their effects by interferometry. Unlike the classic method of coda analysis (CWT), the NCWT does not require the recording of a coda as a reference before damage to the structure. Tn the framework of the PTA-ENDE project, a 1/3 model of a preconstrained concrete containment (EDF VeRCoRs mock-up) is placed under pressure to study the leakage of the structure. During this evaluation protocol, specific areas are monitored by the NCWT (during 5 days, which correspond to the protocol of nuclear power plant pressurization under maintenance test). The acoustic nonlinear response due to the high amplitude of the acoustic modulation gives pertinent information about the elastic and dissipative nonlinearities of the concrete. Tts effective level is evaluated by two nonlinear observables extracted from the interferometry. The increase of nonlinearities is in agreement with the creation of a crack with a network of microcracks located at its base; however, a change in the dynamics of the evolution of the nonlinearities may indicate the opening of a through crack. Tn addition, as during the experimental campaign, reference codas have been recorded. We used CWT to follow the stress evolution and the gas leaks ratio of the structure. Both CWT and NCWT results are presented in this paper.

  6. Detailed simulation of ultrasonic inspections

    International Nuclear Information System (INIS)

    Chaplin, K.R.; Douglas, S.R.; Dunford, D.

    1997-01-01

    Simulation of ultrasonic inspection of engineering components have been performed at the Chalk River Laboratories of AECL for over 10 years. The computer model, called EWE for Elastic Wave Equations, solves the Elastic Wave Equations using a novel finite difference scheme. It simulates the propagation of an ultrasonic wave from the transducer to a flaw, the scatter of waves from the flaw, and measurement of signals at a receive transducer. Regions of different materials, water and steel for example, can be simulated. In addition, regions with slightly different material properties from the parent material can be investigated. The two major types of output are displays of the ultrasonic waves inside the component and the corresponding A-scans. EPRI and other organizations have used ultrasonic models for: defining acceptable ultrasonic inspection procedures, designing and evaluating inspection techniques, and for quantifying inspection reliability. The EWE model has been applied to the inspection of large pipes in a nuclear plant, gas pipeline welds and steam generator tubes. Most recent work has dealt with the ultrasonic inspection of pressure tubes in CANDU reactors. Pressure tube inspections can reliably detect and size defects; however, there are improvements that can be made. For example, knowing the sharpness of a flaw-tip is crucial for fitness for service assessments. Computer modelling of the ultrasonic inspection of flaws with different root radius has suggested inspection techniques that provide flaw tip radius information. A preliminary investigation of these methods has been made in the laboratory. The basis for the model will be reviewed at the presentation. Then the results of computer simulations will be displayed on a PC using an interactive program that analyzes simulated A-scans. This software tool gives inspection staff direct access to the results of computer simulations. (author)

  7. Method and apparatus to characterize ultrasonically reflective contrast agents

    Science.gov (United States)

    Pretlow, Robert A., III (Inventor)

    1993-01-01

    A method and apparatus for characterizing the time and frequency response of an ultrasonically reflective contrast agent is disclosed. An ultrasonically reflective contrast agent is injected, under constant pressure, into a fluid flowing through a pump flow circuit. The fluid and the ultrasonically reflective contrast agent are uniformly mixed in a mixing chamber, and the uniform mixture is passed through a contrast agent chamber. The contrast agent chamber is acoustically and axially interposed between an ultrasonic transducer chamber and an acoustic isolation chamber. A pulse of ultrasonic energy is transmitted into the contrast agent chamber from the ultrasonic transducer chamber. An echo waveform is received from the ultrasonically reflective contrast agent, and it is analyzed to determine the time and frequency response of the ultrasonically reflective contrast agent.

  8. Ultrasonic hydrometer

    Science.gov (United States)

    Swoboda, Carl A.

    1984-01-01

    The disclosed ultrasonic hydrometer determines the specific gravity (density) of the electrolyte of a wet battery, such as a lead-acid battery. The hydrometer utilizes a transducer that when excited emits an ultrasonic impulse that traverses through the electrolyte back and forth between spaced sonic surfaces. The transducer detects the returning impulse, and means measures the time "t" between the initial and returning impulses. Considering the distance "d" between the spaced sonic surfaces and the measured time "t", the sonic velocity "V" is calculated with the equation "V=2d/t". The hydrometer also utilizes a thermocouple to measure the electrolyte temperature. A hydrometer database correlates three variable parameters including sonic velocity in and temperature and specific gravity of the electrolyte, for temperature values between 0.degree. and 40.degree. C. and for specific gravity values between 1.05 and 1.30. Upon knowing two parameters (the calculated sonic velocity and the measured temperature), the third parameter (specific gravity) can be uniquely found in the database. The hydrometer utilizes a microprocessor for data storage and manipulation. The disclosed modified battery has a hollow spacer nub on the battery side wall, the sonic surfaces being on the inside of the nub and the electrolyte filling between the surfaces to the exclusion of intervening structure. An accessible pad exposed on the nub wall opposite one sonic surface allows the reliable placement thereagainst of the transducer.

  9. Advanced ultrasonic inspections

    International Nuclear Information System (INIS)

    Ghia, S.

    1990-08-01

    Acoustic Emission (AE) continuous monitoring and periodical inspections by advanced ultrasonic have been applied to evaluate defect evolution within a PWR reduced scale (1:5) pressure vessel subjected to cyclic mechanical fatigue test. This experimental activity has been carried out in the frame of the Primary Circuit Component Life Prediction programme. In the time period covered by this report actions were performed as following: (1) Ultrasonic examination by multifrequency acoustic holography to evaluate defect evolution subsequently repair and heat treatment of the R2 vessel carried out in March 1988. For the purpose, measurements were performed both at 0 and 200 bar of internal pressure. As uniformity of the procedures adopted, for calibration and testing, made the results comparable with the previous ones no evidence for significant growing of the examined defects has been found. (2) Acoustic emission monitoring has then been carried out during fatigue test from 416000 to 565000 fatigue cycles. Analysis of a large amount of data has been performed paying particular attention to the distinction between friction phenomena and crack growth in order to obtain a correct diagnosis of flaw evolution. The signal duration distribution and the correlation of AE appearance time versus load cycle phase were considered to characterise stick-slip processes. A general intensification of AE activity has been recorded during this last period of monitoring and previous known AE sources were confirmed together with the appearance of new AE sources some of them correlable with real defects

  10. Black rings

    International Nuclear Information System (INIS)

    Emparan, Roberto; Reall, Harvey S

    2006-01-01

    A black ring is a five-dimensional black hole with an event horizon of topology S 1 x S 2 . We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

  11. White Ring; White ring

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, H.; Yuzawa, H. [Nikken Sekkei Ltd., Osaka (Japan)

    1998-01-05

    White Ring is a citizen`s gymnasium used for figure skating and short track speed skating games of 18th Winter Olympic Games in 1998. White Ring is composed of a main-arena and a sub-arena. For the main-arena with an area 41mtimes66m, an ice link can be made by disengaging the potable floor and by flowing brine in the bridged polystyrene pipes embedded in the concrete floor. Due to the fortunate groundwater in this site, well water is used for the outside air treatment energy in 63% during heating and in 35% during cooling. Ammonia is used as a cooling medium for refrigerating facility. For the heating of audience area in the large space, heat load from the outside is reduced by enhancing the heat insulation performance of the roof of arena. The audience seats are locally heated using heaters. For the White Ring, high quality environment is realized for games through various functions of the large-scale roof of the large space. Success of the big event was expected. 15 figs., 4 tabs.

  12. Effects of the temperature and pressure on the electronic and optical properties of an exciton in GaAs/Ga1-xAlxAs quantum ring

    Science.gov (United States)

    El-Bakkari, K.; Sali, A.; Iqraoun, E.; Rezzouk, A.; Es-Sbai, N.; Ouazzani Jamil, M.

    2018-06-01

    Using a variational approach, we have calculated the binding energies (E1s,2sb) and interband emission energy (Eph) of an exciton confined in GaAs / Ga1 - x Alx As quantum rings (QRs) structures under effects of the temperature and pressure, in the effective mass approximation. We have taken into consideration the difference in the effective masses of the charge carriers in two materials, well and barrier. The results that we have obtained show clearly that E1s,2sb and Eph are influenced by the structure geometries of QR (height H, radial thickness Δ R and potential barrier), the temperature and pressure. Indeed, with a smaller geometric parameter, E1s,2sb and Eph become higher due to the improvement in confinement of the charge carriers. We have also observed that for a given value of the temperature, the pressure leads to an increasing of the E1s,2sb and Eph , and the latter quantities are decreasing with temperature. In addition, these variations of the E1s,2sb and Eph under the external perturbations are more remarkable in small H for fixed Δ R , and for larger Δ R for a given value of the H, because for the choice of a finite height of the barrier in the z direction and an infinite confinement in ρ direction.

  13. Automatic ultrasonic pre-service, and in-service inspection of pressurized components of the primary circuit of nuclear power stations

    International Nuclear Information System (INIS)

    Muller, G.P.; Hallermeier, L.; Heinrich, D.; Grabendorfer, W.; Rebrmann, M.

    1985-01-01

    Ultrasonic pre-service and especially in-service inspection activities on the primary circuit of nuclear power stations form an essential part of the maintenance work that must be performed throughout the lifetime to ensure plant integrity. Consequently, the equipment required to carry out these inspections must be continuously improved in respect of reliability, safety, accuracy and ease of handling in order to minimize disturbances and repairs and reduce radiation exposure of the personnel. The authors' discussion of technique, equipment and performance of automated ultrasonic inspection is based on 15 years of experience in the testing of components of the primary circuit in nuclear power stations. To cover all inspection areas of the RPV of a PWR, four different manipulators are required, two for the closure head, one for the studs and one for the cylindrical shell and bottom closure. The use of the newly developed equipment, which naturally meets all the recommendations of the licensing authorities, allows for the automatic inspection of the components of primary circuit of nuclear power stations and the thus helps to substantially decrease the radiation exposure of the personnel. All the manipulators and their control consoles were designed and manufactured by M.A.N., Nuremberg while the ultrasonic electronic system was developed by Krautkramer, Cologne

  14. The optimization of a tubular condensation cryopump for pressures below 10/sup -13/ Torr (for intersecting storage rings for protons)

    CERN Document Server

    Benvenuti, C

    1974-01-01

    A cryopump design of tubular geometry is presented, which incorporates in its vacuum system only a very small fraction of ambient temperature walls. Furthermore, the total amount of the 300K radiation reaching the cold baffles is reduced by about two orders of magnitude. This has the double advantage that the baffles can be cooled at lower temperatures and can be allowed to be more 'transparent' to radiation and hence to molecules. The new model has been entirely optimised both for molecular and radiation transmission by a Monte Carlo method. It is designed to have a pumping speed of 3000 ls/sup -1/ for H/sub 2/ at the two entrances, an axial conductance providing a pressure drop across the pump of a factor of ten and a limit pressure in the 10/sup -14/ Torr range. (6 refs).

  15. Vortex rings

    CERN Document Server

    Akhmetov, D G

    2009-01-01

    This text on vortex rings covers their theoretical foundation, systematic investigations, and practical applications such as the extinction of fires at gushing oil wells. It pays special attention to the formation and motion of turbulent vortex rings.

  16. The Locations of Ring Current Pressure Peaks: Comparison of TWINS Measurements and CIMI Simulations for the 7-10 September 2015 CIR Storm

    Science.gov (United States)

    Hill, S. C.; Edmond, J. A.; Xu, H.; Perez, J. D.; Fok, M. C. H.; Goldstein, J.; McComas, D. J.; Valek, P. W.

    2017-12-01

    The characteristics of a four day 7-10 September 2015 co-rotating interaction region (CIR) storm (min. SYM/H ≤ -110 nT) are categorized by storm phase. Ion distributions of trapped particles in the ring current as measured by the Two Wide-Angle Imaging Neutral Atom Spectrometers (TWINS) are compared with the simulated ion distributions of the Comprehensive Inner Magnetosphere-Ionosphere Model (CIMI). The energetic neutral atom (ENA) images obtained by TWINS are deconvolved to extract equatorial pitch angle, energy spectra, ion pressure intensity, and ion pressure anisotropy distributions in the inner magnetosphere. CIMI, using either a self-consistent electric field or a semi-empirical electric field, simulates comparable distributions. There is good agreement between the data measured by TWINS and the different distributions produced by the self-consistent electric field and the semi-empirical electric field of CIMI. Throughout the storm the pitch angle distribution (PAD) is mostly perpendicular in both CIMI and TWINS and there is agreement between the anisotropy distributions. The locations of the ion pressure peaks seen by TWINS and by the self-consistent and semi empirical electric field parameters in CIMI are usually between dusk and midnight. On average, the self-consistent electric field in CIMI reveals ion pressure peaks closer to Earth than its semi empirical counterpart, while TWINS reports somewhat larger radial values for the ion pressure peak locations. There are also notable events throughout the storm during which the simulated observations show some characteristics that differ from those measured by TWINS. At times, there are ion pressure peaks with magnetic local time on the dayside and in the midnight to dawn region. We discuss these events in light of substorm injections indicated by fluctuating peaks in the AE index and a positive By component in the solar wind. There are also times in which there are multiple ion pressure peaks. This may

  17. Ultrasonic Resonance Spectroscopy of Composite Rims for Flywheel Rotors

    Science.gov (United States)

    Harmon, Laura M.; Baaklini, George Y.

    2002-01-01

    Flywheel energy storage devices comprising multilayered composite rotor systems are being studied extensively for utilization in the International Space Station. These composite material systems were investigated with a recently developed ultrasonic resonance spectroscopy technique. The ultrasonic system employs a continuous swept-sine waveform and performs a fast Fourier transform (FFT) on the frequency response spectrum. In addition, the system is capable of equalizing the amount of energy at each frequency. Equalization of the frequency spectrum, along with interpretation of the second FFT, aids in the evaluation of the fundamental frequency. The frequency responses from multilayered material samples, with and without known defects, were analyzed to assess the capabilities and limitations of this nondestructive evaluation technique for material characterization and defect detection. Amplitude and frequency changes were studied from ultrasonic responses of thick composite rings and a multiring composite rim. A composite ring varying in thickness was evaluated to investigate the full thickness resonance. The frequency response characteristics from naturally occurring voids in a composite ring were investigated. Ultrasonic responses were compared from regions with and without machined voids in a composite ring and a multiring composite rim. Finally, ultrasonic responses from the multiring composite rim were compared before and after proof spin testing to 63,000 rpm.

  18. Technique for ultrasonic testing of austenitic steel weldments of NPP components

    International Nuclear Information System (INIS)

    Lantukh, V.M.; Grebennik, V.S.; Kordinov, E.V.; Kesler, N.A.; Shchedrin, I.F.

    1987-01-01

    Special literature on ultrasonic testing of weldments of austenitic steel is analysed. Technique for ultrasonic testing of the ring and longitudinal butt welded joints of NPP components without reinforcing bead removal is described. Special converter design and fabrication practice are described. Results of experimental check of the developed testing technology and its application during NNPs' mounting and operation are presented. Results of ultrasonic and X-ray testing are compared

  19. Monitoring of PHWR end cap weld quality by ultrasonic testing

    International Nuclear Information System (INIS)

    Laxminarayana, B.

    1996-01-01

    In Pressurized Heavy Water Reactor fuel fabrication, the end cap welding is an important process. Till date about 16,000 welds have been studied ultrasonically. This paper discusses the experimental results and the design of a semi automatic ultrasonic equipment incorporating features for both backward and forward integration. (author)

  20. Ultrasonic sensor for sodium perspective device

    International Nuclear Information System (INIS)

    Ogawa, Fujio; Onuki, Koji.

    1995-01-01

    The present invention concerns an ultrasonic wave sensor for a sodium perspective device disposed in an FBR type reactor, which can change the directing angle of the ultrasonic sensor irrespective of the external conditions in liquid sodium. Namely, the sensor comprises (1) a sensor main body, (2) a diaphragm disposed on an oscillating surface of ultrasonic waves generated from the sensor main body, (3) a pressurizing and depressurizing nozzle connected to the sensor main body, and (4) a pressure detector disposed to these nozzles. A gas is charged/discharged to and from the sensor main body to control a gas pressure in the main body. If the gas pressure is made higher, the diaphragm is deformed convexly. If the gas pressure is lowered, the diaphragm is deformed concavely. The directing angle is greater when it is deformed a convexly, and it is smaller when it is deformed concavely. Accordingly, ultrasonic wave receiving/sending range in the sodium can be varied optionally by controlling the gas pressure in the main body. (I.S.)

  1. Standard practice for leaks using ultrasonics

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 Practice A, Pressurization—This practice covers procedures for calibration of ultrasonic instruments, location, and estimated measurements of gas leakage to atmosphere by the airborne ultrasonic technique. 1.2 In general practice this should be limited to leaks detected by two classifications of instruments, Class I and Class II. Class I instruments should have a minimum detectable leak rate of 6.7 × 10−7 mol/s (1.5 × 10−2 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Class II instruments should have a minimal detectable leak rate of 6.7 × 10−6 mol/s (1.5 × 10−1 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Refer to Guide E432 for additional information. 1.3 Practice B, Ultrasonic Transmitter—For object under test not capable of being pressurized but capable of having ultrasonic tone placed/injected into the test area to act as an ultrasonic leak trace source. 1.3.1 This practice is limited to leaks producing leakage o...

  2. High-resolution ultrasonic spectroscopy

    Directory of Open Access Journals (Sweden)

    V. Buckin

    2018-03-01

    Full Text Available High-resolution ultrasonic spectroscopy (HR-US is an analytical technique for direct and non-destructive monitoring of molecular and micro-structural transformations in liquids and semi-solid materials. It is based on precision measurements of ultrasonic velocity and attenuation in analysed samples. The application areas of HR-US in research, product development, and quality and process control include analysis of conformational transitions of polymers, ligand binding, molecular self-assembly and aggregation, crystallisation, gelation, characterisation of phase transitions and phase diagrams, and monitoring of chemical and biochemical reactions. The technique does not require optical markers or optical transparency. The HR-US measurements can be performed in small sample volumes (down to droplet size, over broad temperature range, at ambient and elevated pressures, and in various measuring regimes such as automatic temperature ramps, titrations and measurements in flow.

  3. [Destruction of synovial pannus of antigen-induced arthritis by ultrasonic cavitation in rabbits].

    Science.gov (United States)

    Zhang, Ling-yan; Qiu, Li; Wang, Lei; Lin, Ling; Wen, Xiao-rong

    2011-11-01

    To optimize the conditions of ultrasonic irradiation and microbubble of ultrasound cavitation on destruction of synovial pannus of antigen-induced arthritis (AIA) in rabbits. Antigen-induced arthritis was successfully induced on bilateral knee joints of 85 rabbits. Each 10 AIA rabbits were divided into two groups to compare various peak negative pressures, different ultrasonic pulse durations, various pulse repetition frequencies, different irradiance duration, different dosages of microbubble contrast agents, different ultrasonic irradiance times. With intravenous infusion of Sonovue to the rabbits, ultrasonic irradiance was performed on the right knee joint using the above condition of ultrasound cavitation. At the day 1 after ultrasonic irradiance, MRI and pathological examination were employed to evaluate the optimal conditions. The optimal parameters and conditions for ultrasonic irradiance included intermittent ultrasonic application (in 6 s intervals), 0.6 mL/kg of microbubble contrast agent, 4.6 MPa of ultrasonic peak negative pressure, 100 cycles of pulse duration, 50 Hz of pulse repetition frequency, 5 min of ultrasonic duration, 0.6 mL/kg of dosages of microbubble contrast agents and multi-sessional ultrasonic irradiance. After the ultrasonic irradiance, the thickness of right knee synovium measured by MRI was thinner than that of left knee and synovial necrosis was confirmed by the pathological finding. Under optimal ultrasonic irradiation and microbubble conditions, ultrasonic cavitation could destroy synovial pannus of AIA in rabbits.

  4. Ultrasonic horn design for ultrasonic machining technologies

    Directory of Open Access Journals (Sweden)

    Naď M.

    2010-07-01

    Full Text Available Many of industrial applications and production technologies are based on the application of ultrasound. In many cases, the phenomenon of ultrasound is also applied in technological processes of the machining of materials. The main element of equipments that use the effects of ultrasound for machining technology is the ultrasonic horn – so called sonotrode. The performance of ultrasonic equipment, respectively ultrasonic machining technologies depends on properly designed of sonotrode shape. The dynamical properties of different geometrical shapes of ultrasonic horns are presented in this paper. Dependence of fundamental modal properties (natural frequencies, mode shapes of various sonotrode shapes for various geometrical parameters is analyzed. Modal analyses of the models are determined by the numerical simulation using finite element method (FEM design procedures. The mutual comparisons of the comparable parameters of the various sonotrode shapes are presented.

  5. Flushing Ring for EDM

    Science.gov (United States)

    Earwood, L.

    1985-01-01

    Removing debris more quickly lowers cutting time. Operation, cutting oil and pressurized air supplied to ring placed around workpiece. Air forces oil through small holes and agitates oil as it flows over workpiece. High flow rate and agitation dislodge and remove debris. Electrical discharge removes material from workpiece faster.

  6. Electromagnetic ultrasonic guided waves

    CERN Document Server

    Huang, Songling; Li, Weibin; Wang, Qing

    2016-01-01

    This book introduces the fundamental theory of electromagnetic ultrasonic guided waves, together with its applications. It includes the dispersion characteristics and matching theory of guided waves; the mechanism of production and theoretical model of electromagnetic ultrasonic guided waves; the effect mechanism between guided waves and defects; the simulation method for the entire process of electromagnetic ultrasonic guided wave propagation; electromagnetic ultrasonic thickness measurement; pipeline axial guided wave defect detection; and electromagnetic ultrasonic guided wave detection of gas pipeline cracks. This theory and findings on applications draw on the author’s intensive research over the past eight years. The book can be used for nondestructive testing technology and as an engineering reference work. The specific implementation of the electromagnetic ultrasonic guided wave system presented here will also be of value for other nondestructive test developers.

  7. Ultrasonic flow measurements for irrigation process monitoring

    Science.gov (United States)

    Ziani, Elmostafa; Bennouna, Mustapha; Boissier, Raymond

    2004-02-01

    This paper presents the state of the art of the general principle of liquid flow measurements by ultrasonic method, and problems of flow measurements. We present an ultrasonic flowmeter designed according to smart sensors concept, for the measurement of irrigation water flowing through pipelines or open channels, using the ultrasonic transit time approach. The new flowmeter works on the principle of measuring time delay differences between sound pulses transmitted upstream and downstream in the flowing liquid. The speed of sound in the flowing medium is eliminated as a variable because the flowrate calculations are based on the reciprocals of the transmission times. The transit time difference is digitally measured by means of a suitable, microprocessor controlled logic. This type of ultrasonic flowmeter will be widely used in industry and water management, it is well studied in this work, followed by some experimental results. For pressurized channels, we use one pair of ultrasonic transducer arranged in proper positions and directions of the pipe, in this case, to determine the liquid velocity, a real time on-line analysis taking account the geometries of the hydraulic system, is applied to the obtained ultrasonic data. In the open channels, we use a single or two pairs of ultrasonic emitter-receiver according to the desired performances. Finally, the goals of this work consist in integrating the smart sensor into irrigation systems monitoring in order to evaluate potential advantages and demonstrate their performance, on the other hand, to understand and use ultrasonic approach for determining flow characteristics and improving flow measurements by reducing errors caused by disturbances of the flow profiles.

  8. Ultrasonic testing device

    International Nuclear Information System (INIS)

    Lawrie, W.E.

    1978-01-01

    The ultrasonic transmitter made of polarized ferroelectric ceramic material (lead zirconate titanate) is arranged in a strip carrier which allows it to be introduced between the fuel elements of a fuel subassembly in a water cooled nuclear reactor. The ultrasonic transmitter is insulated relative to the carrier. The echo of the ra dal ultrasonic pulse is recorded which changes as faulty water filled fuel elements are detected. (RW) [de

  9. Calculations for piezoelectric ultrasonic transducers

    International Nuclear Information System (INIS)

    Jensen, H.

    1986-05-01

    Analysis of piezoelectric ultrasonic transducers implies a solution of a boundary value problem, for a body which consists of different materials, including a piezoelectric part. The problem is dynamic at frequencies, where a typical wavelength is somewhat less than the size of the body. Radiation losses as well as internal losses may be important. Due to the complexity of the problem, a closed form solution is the exception rather than the rule. For this reason, it is necessary to use approximate methods for the analysis. Equivalent circuits, the Rayleigh-Ritz method, Mindlin plate theory and in particular the finite element method are considered. The finite element method is utilized for analysis of axisymmetric transducers. An explicit, fully piezoelectric, triangular ring element, with linear variations in displacement and electric potential is given. The influence of a fluid half-space is also given, in the form of a complex stiffness matrix. A special stacking procedure, for analysis of the backing has been developed. This procedure gives a saving, which is similar to that of the fast fourier transform algorithm, and is also wellsuited for analysis of finite and infinite waveguides. Results obtained by the finite element method are shown and compared with measurements and exact solutions. Good agreement is obtained. It is concluded that the finite element method can be a valueable tool in analysis and design of ultrasonic transducers. (author)

  10. Electrical and spectral characteristics of an atmospheric pressure argon plasma jet generated with tube-ring electrodes in surface dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Y. [Institute of Electrostatics and Special Power, Dalian University of Technology, Dalian 116024 (China); Department of Physics and Electrical Engineering, Weinan Teachers University, Weinan 71400 (China); Lu, N. [Institute of Electrostatics and Special Power, Dalian University of Technology, Dalian 116024 (China); Pan, J. [Department of Physics and Electrical Engineering, Weinan Teachers University, Weinan 71400 (China); Li, J., E-mail: lijie@dlut.edu.cn [Institute of Electrostatics and Special Power, Dalian University of Technology, Dalian 116024 (China); Wu, Y. [Institute of Electrostatics and Special Power, Dalian University of Technology, Dalian 116024 (China)

    2013-03-01

    An atmospheric-pressure argon plasma jet is generated with tube-ring electrodes in surface dielectric barrier discharge by a sinusoidal excitation voltage at 8 kHz. The electrical and spectral characteristics are estimated such as conduction and displacement current, electric-field, electron temperature, rotational temperature of N{sub 2} and OH, electronic excitation temperature, and oxygen atomic density. It is found that the electric-field magnitudes in the top area of the ground electrode are higher than that in the bottom area of the power electrode, and the electron temperature along radial direction is in the range of 9.6–10.4 eV and along axial direction in the range of 4.9–10 eV. The rotational temperature of N{sub 2} obtained by comparing the simulated spectrum with the measured spectrum at the C{sup 3}Π{sub u} → B{sup 3}Π{sub g}(Δv = − 2) band transition is in the range of 342–387 K, the electronic excitation temperature determined by Boltzmann's plot method is in the range of 3188–3295 K, and the oxygen atomic density estimated by the spectral intensity ratio of atomic oxygen line λ = 844.6 nm to argon line λ = 750.4 nm is in the order of magnitude of 10{sup 16} cm{sup −3}, respectively. - Highlights: ► The conduction and displacement current are calculated by equivalent circuit diagram. ► The 2D distribution of electric-field magnitude is calculated by ElecNet software. ► The electron temperature along axial direction is in the range of 4.9–10 eV. ► The oxygen atomic density is about a magnitude of 10{sup 16} cm{sup −3}.

  11. A novel in-plane mode rotary ultrasonic motor

    Directory of Open Access Journals (Sweden)

    Lu Xiaolong

    2014-04-01

    Full Text Available Ultrasonic motors have the merits of high ratio of torque to volume, high positioning precision, intrinsic holding torque, etc., compared to the conventional electromagnetic motors. There have been several potential applications for this type of motor in aerospace exploration, but bearings and bonding mechanism of the piezoelectric ring in the motors limit the performance of them in the space operation conditions. It is known that the Langevin type transducer has excellent energy efficiency and reliability. Hence using the Langevin type transducer in ultrasonic motors may improve the reliability of piezoelectric motors for space applications. In this study, a novel in-plane mode rotary ultrasonic motor is designed, fabricated, and characterized. The proposed motor operates in in-plane vibration mode which is excited by four Langevin-type bending vibrators separately placed around a ring-shaped stator. Two tapered rotors are assembled to the inner ring of the stator and clamped together by a screw nut. In order to make the motor more stable and convenient to fix, a thin cylindrical support is placed under the stator ring. Due to its no-bearing structure and Langevin transducer excitation, the prototype ultrasonic motor may operate well in aeronautic and astronautic environments.

  12. Researches on the Piston Ring

    Science.gov (United States)

    Ehihara, Keikiti

    1944-01-01

    In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and

  13. ring system

    African Journals Online (AJOL)

    1,3,2-DIAZABORACYCLOALKANE. RING SYSTEM. Negussie Retta" and Robert H. Neilson. 'Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia. Department of Chemistry, Texas Christian University.

  14. Planetary Rings

    Science.gov (United States)

    Nicholson, P. D.

    2001-11-01

    A revolution in the studies in planetary rings studies occurred in the period 1977--1981, with the serendipitous discovery of the narrow, dark rings of Uranus, the first Voyager images of the tenuous jovian ring system, and the many spectacular images returned during the twin Voyager flybys of Saturn. In subsequent years, ground-based stellar occultations, HST observations, and the Voyager flybys of Uranus (1986) and Neptune (1989), as well as a handful of Galileo images, provided much additional information. Along with the completely unsuspected wealth of detail these observations revealed came an unwelcome problem: are the rings ancient or are we privileged to live at a special time in history? The answer to this still-vexing question may lie in the complex gravitational interactions recent studies have revealed between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto parent bodies. Perhaps most puzzling is Saturn's multi-stranded, clumpy F ring, which continues to defy a simple explanation 20 years after it was first glimpsed in grainy images taken by Pioneer 11. Voyager and HST images reveal a complex, probably chaotic, dynamical interaction between unseen parent bodies within this ring and its two shepherd satellites, Pandora and Prometheus. The work described here reflects contributions by Joe Burns, Jeff Cuzzi, Luke Dones, Dick French, Peter Goldreich, Colleen McGhee, Carolyn Porco, Mark Showalter, and Bruno Sicardy, as well as those of the author. This research has been supported by NASA's Planetary Geology and Geophysics program and the

  15. Ultrasonic flow meter

    NARCIS (Netherlands)

    Lötters, Joost Conrad; Snijders, G.J.; Volker, A.W.F.

    2014-01-01

    The invention relates to an ultrasonic flow meter comprising a flow tube for the fluid whose flow rate is to be determined. The flow meter comprises a transmitting element for emitting ultrasonic waves, which is provided on the outer jacket of the flow tube. A receiving element, which is provided on

  16. A Method of Estimating Pressure and Intensity Distributions of Multielement Phased Array High Intensity Focused Ultrasonic Field at Full Power Using a Needle Hydrophone

    International Nuclear Information System (INIS)

    Yu Ying; Shen Guofeng; Bai Jingfeng; Chen Yazhu

    2011-01-01

    The pressure and intensity distribution of high intensity focused ultrasound (HIFU) fields at full power are critical for predicting heating patterns and ensuring safety of the therapy. With the limitations of maximum pressure at the hydrophone and damage from cavitation or thermal effects, it is hard to measure pressure and intensity directly when HIFU is at full power. HIFU-phased arrays are usually composed of large numbers of small elements and the sound power radiated from some of them at full power is measureable using a hydrophone, we grouped them based on the limitation of maximum permissible pressure at the hydrophone and the characteristics of the element arrangement in the array. Then sound field measurement of the group was carried out at full power level. Using the acoustic coherence principle, the pressure and intensity distribution of the array at full power level can be calculated from corresponding values from the groups. With this method, computer simulations and sound field measurement of a 65-element concentric distributed phased array was carried out. The simulation results demonstrate theoretically the feasibility of this method. Measurements on the 65-element phased array also verify the effectiveness of this method for estimating the pressure and intensity distribution of phased array at full power level using a needle hydrophone.

  17. Control of hydrodynamic cavitation using ultrasonic

    Science.gov (United States)

    Chatterjee, Dhiman; Arakeri, Vijay H.

    2003-11-01

    Hydrodynamic cavitation is known to have many harmful effects like surface damage and generation of noise. We investigated the use of ultrasonics to control traveling bubble cavitation. Ultrasonic pressure field, produced by a piezoelectric crystal, was applied to modify the nuclei size distribution. Effects of continuous-wave (CW) and pulsed excitations were studied. At low dissolved gas content the CW-mode performed better than the pulsed one, whereas for high gas content the pulsed one was more effective. The dominant mechanisms were Bjerknes force and rectified diffusion in these two cases. Simultaneous excitation by two crystals in CW and pulsed modes was seen to control cavitation better.

  18. Linear and nonlinear optical absorption coefficients in GaAs/Ga{sub 1-x}Al{sub x}As concentric double quantum rings: Effects of hydrostatic pressure and aluminum concentration

    Energy Technology Data Exchange (ETDEWEB)

    Baghramyan, H.M. [Department of Solid State Physics, Yerevan State University, Al. Manookian 1, 0025 Yerevan (Armenia); Barseghyan, M.G., E-mail: mbarsegh@ysu.am [Department of Solid State Physics, Yerevan State University, Al. Manookian 1, 0025 Yerevan (Armenia); Kirakosyan, A.A. [Department of Solid State Physics, Yerevan State University, Al. Manookian 1, 0025 Yerevan (Armenia); Restrepo, R.L. [Escuela de Ingenieria de Antioquia, AA 7516 Medellin (Colombia); Duque, C.A. [Instituto de Fisica, Universidad de Antioquia, AA 1226 Medellin (Colombia)

    2013-02-15

    The linear and nonlinear intra-band optical absorption coefficients in GaAs/Ga{sub 1-x}Al{sub x}As two-dimensional concentric double quantum rings are investigated. Taking into account the combined effects of hydrostatic pressure and aluminum concentration the energies of the ground (n=1,l=0) and the first excited state (n=2,l=1) have been found using the effective mass approximation and the transfer matrix formalism. The energies of these states and the corresponding threshold energy of the intra-band optical transitions are examined as a function of hydrostatic pressure and aluminum concentration for different sizes of the structure. We also investigated the dependencies of the linear, nonlinear, and total optical absorption coefficients as functions of the incident photon energy for different values of hydrostatic pressure, aluminum concentration, sizes of the structure, and incident optical intensity. Its is found that the effects of the hydrostatic pressure and the aluminum concentration lead to a shifting of the resonant peaks of the intra-band optical spectrum. - Highlights: Black-Right-Pointing-Pointer Linear and nonlinear intra-band absorption in quantum rings. Black-Right-Pointing-Pointer Threshold energy strongly depends on the hydrostatic pressure. Black-Right-Pointing-Pointer Threshold energy strongly depends on the stoichiometry and sizes of structure. Black-Right-Pointing-Pointer Optical absorption is affected by the incident optical intensity.

  19. Optimization of hydrostatic pressure at varied sonication conditions--power density, intensity, very low frequency--for isothermal ultrasonic sludge treatment.

    Science.gov (United States)

    Delmas, Henri; Le, Ngoc Tuan; Barthe, Laurie; Julcour-Lebigue, Carine

    2015-07-01

    This work aims at investigating for the first time the key sonication (US) parameters: power density (DUS), intensity (IUS), and frequency (FS) - down to audible range, under varied hydrostatic pressure (Ph) and low temperature isothermal conditions (to avoid any thermal effect). The selected application was activated sludge disintegration, a major industrial US process. For a rational approach all comparisons were made at same specific energy input (ES, US energy per solid weight) which is also the relevant economic criterion. The decoupling of power density and intensity was obtained by either changing the sludge volume or most often by changing probe diameter, all other characteristics being unchanged. Comprehensive results were obtained by varying the hydrostatic pressure at given power density and intensity. In all cases marked maxima of sludge disintegration appeared at optimum pressures, which values increased at increasing power intensity and density. Such optimum was expected due to opposite effects of increasing hydrostatic pressure: higher cavitation threshold then smaller and fewer bubbles, but higher temperature and pressure at the end of collapse. In addition the first attempt to lower US frequency down to audible range was very successful: at any operation condition (DUS, IUS, Ph, sludge concentration and type) higher sludge disintegration was obtained at 12 kHz than at 20 kHz. The same values of optimum pressure were observed at 12 and 20 kHz. At same energy consumption the best conditions - obtained at 12 kHz, maximum power density 720 W/L and 3.25 bar - provided about 100% improvement with respect to usual conditions (1 bar, 20 kHz). Important energy savings and equipment size reduction may then be expected. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. BERKELEY: ALS ring

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-06-15

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  1. BERKELEY: ALS ring

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  2. Ultrasonic hot powder compaction of Ti-6Al-4V.

    Science.gov (United States)

    Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

    2017-07-01

    Power ultrasonic has been recently employed in a wide variety of manufacturing processes among which ultrasonic assisted powder compaction is a promising powder materials processing technique with significant industrial applications. The products manufactured by the powder metallurgy commonly consist of residual porosities, material impurities, structural non-homogeneities and residual stress. In this paper, it is aimed to apply power ultrasonic to the hot consolidation process of Ti-6Al-4V titanium alloy powder in order to improve mechanical properties. To do this, the effects of ultrasonic power and process temperature and pressure were considered and then deeply studied through a series of experiments. It was shown that the addition of ultrasonic vibration leads to a significant improvement in the consolidation performance and the mechanical strength of the fabricated specimens. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The ultrasonic shop map and its use in preservice inspection

    International Nuclear Information System (INIS)

    Caplan, J.S.

    1975-01-01

    Prior to the introduction of Section X1 of the ASME Code on Inservice Inspection, a plan was introduced by Westinghouse to perform ultrasonic examinations of areas of high stress and high fluence of reactor pressure vessels in the manufacturer's shop and subsequent to the shop hydrostatic test. The tests provided a shop reference map of ultrasonic responses to use in subsequent preservice and inservice inspections, and attempted to locate any ultrasonic reflections beyond the acceptance standards of ASME Section III and, later, of Section X1. The history of the program is reviewed. Thirty-six vessels were examined during 1970 to 1973. As a result of indications discovered during ultrasonic examination repairs were carried out on five of these. Details are given of inspections and repairs. A summary is also given of the indications detected and of the correlations between the ultrasonic evaluation and actual flow characteristics. (U.K.)

  4. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Drews, J.; Leipold, Frank

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N2/O2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can...

  5. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    International Nuclear Information System (INIS)

    Kusano, Y; Drews, J; Leipold, F; Fateev, A; Bardenshtein, A; Krebs, N

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N 2 /O 2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can enhance ozone production especially when the DBD was driven at a frequency of 15 kHz.

  6. Gliding arc surface treatment of glass-fiber-reinforced polyester enhanced by ultrasonic irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Norrman, Kion; Drews, Joanna Maria

    2011-01-01

    . The efficiency of such a plasma treatment at atmospheric pressure can be further improved by ultrasonic irradiation onto the surface during the treatment. In the present work glass fiber reinforced polyester (GFRP) plates are treated using an atmospheric pressure gliding arc with and without ultrasonic...

  7. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

  8. Topological rings

    CERN Document Server

    Warner, S

    1993-01-01

    This text brings the reader to the frontiers of current research in topological rings. The exercises illustrate many results and theorems while a comprehensive bibliography is also included. The book is aimed at those readers acquainted with some very basic point-set topology and algebra, as normally presented in semester courses at the beginning graduate level or even at the advanced undergraduate level. Familiarity with Hausdorff, metric, compact and locally compact spaces and basic properties of continuous functions, also with groups, rings, fields, vector spaces and modules, and with Zorn''s Lemma, is also expected.

  9. Ring accelerators

    International Nuclear Information System (INIS)

    Gisler, G.; Faehl, R.

    1983-01-01

    We present two-dimensional simulations in (r-z) and r-theta) cylinderical geometries of imploding-liner-driven accelerators of rings of charged particles. We address issues of azimuthal and longitudinal stability of the rings. We discuss self-trapping designs in which beam injection and extraction is aided by means of external cusp fields. Our simulations are done with the 2-1/2-D particle-in-cell plasma simulation code CLINER, which combines collisionless, electromagnetic PIC capabilities with a quasi-MHD finite element package

  10. A non-destructive, ultrasonic method for the determination of internal pressure and gas composition in an LWR fuel rod on-going and future programme

    International Nuclear Information System (INIS)

    Ferrandis, J.; Leveque, G.; Villard, J.

    2006-01-01

    Several possible non-destructive methods have been investigated in the past to measure the internal gas pressure e.g., measurement of 85 Kr directly, or after accumulation in the plenum by freezing with liquid nitrogen. However no satisfactory resolution to the problem has been found, so at present there is no rapid and accurate method of determining the fission gas pressure in a fuel rod without puncturing the cladding. This procedure is time-consuming and expensive and as a consequence a relatively small number of measurements are generally made compared with the number of fuel rods irradiated. In this paper it is proposed a new method for the measurement of pressure that is: Non-destructive; Non-invasive (i.e., allows re-irradiation of the measured rod); Easy to operate - directly in the reactor pool; Can be used on the critical path; Is inexpensive compared with the methods currently in use. This method is also being adapted to the on line measurement of fission gas release on fuel irradiation in research reactors. This method is based on the application of acoustic technology

  11. Track type ultrasonic inspection device

    International Nuclear Information System (INIS)

    Kajiyama, Shigeru; Sasaki, Tsukasa; Takahisa, Kazuo.

    1993-01-01

    The present invention concerns an improvement of a scanning device disposed near an object to be inspected such as a nuclear pressure vessel and having an ultrasonic probe, mounted thereon that travel along a running track. Specifically, one of wheel supports on both sides is attached being secured to the scanning device. The other of the supports is capable of fixing and releasing, as well as providing and releasing pressure to and from wheels upon mounting and detachment. This enables to provide a structure capable of pressing the wheels of the running device to the plane of the track and release thereof. Accordingly, it is possible to improve the running performance, reduce the size and weight and shorten the time for mounting and detachment of the running inspection device. (I.S.)

  12. Ring interferometry

    CERN Document Server

    Malykin, Grigorii B; Zhurov, Alexei

    2013-01-01

    This monograph is devoted to the creation of a comprehensive formalism for quantitative description of polarized modes' linear interaction in modern single-mode optic fibers. The theory of random connections between polarized modes, developed in the monograph, allows calculations of the zero shift deviations for a fiber ring interferometer. The monograph addresses also the

  13. Ultrasonic testing X gammagraphy

    International Nuclear Information System (INIS)

    Mello Campos, A.M. de

    1989-01-01

    The experience of 10 years for substituting gammagraphy tests by ultrasonic tests is related. A comparative evaluation of data obtained from both techniques applied to welded butt joints is presented. (author)

  14. Ultrasonic grinding method

    International Nuclear Information System (INIS)

    Miyahara, Shuji.

    1990-01-01

    An ultrasonic generator and a liquid supply nozzle are opposed to an object to be ground and a pump is started in this state to supply an organic solvent. Matters to be decontaminated which adheres to the surface of the object to be ground and are difficult to be removed by a mere mechanical removing method can be eliminated previously by the surface active effect of the organic solvent such as ethanol prior to the oscillation of the ultrasonic generator. Subsequently, when the ultrasonic generator is oscillated, scales in the floated state can be removed simply. Further, since the organic solvent can penetrate to provide the surface active effect even in such a narrow portion that the top end of the ultrasonic generator is difficult to the intruded at the surface of the object to be ground, the decontaminating treatment can be applied also to such a narrow portion. (T.M.)

  15. Development of ultrasonic instrument 'UT1000 Series'

    International Nuclear Information System (INIS)

    Ogura, Yukio; Ikeda, Toshimichi

    1984-01-01

    The ultrasonic flaw detectors with 'A-scope indication' have been frequently used as the means for confirming the soundness of structures and equipments, but there are problems in their operational, quantifying and recording capabilities. Recently, the digital ultrasonic measuring instrument of touch panel type ''UT 1000 Series'' has been developed, which resolves these problems by a single effort. This measuring instrument is that of portable type, which gives the digital output of measured results in real time only by lightly touching the peak point of an echo on the Brown tube. This instrument contains the rich software for measurement, and can measure the positions and dimensions of defects and the pressure on contact surfaces with high accuracy. 'A-scope indication' is the indication with an oscilloscope taking the intensity of echo and the propagation time of ultrasonic waves on the ordinate and abscissa, respectively. There are three types of the instrument, that is, for detecting defects, for measuring contact surface pressure and for both purposes. The size of the instrument is 240 mm width, 350 mm length and 175 mm height, and the weight is 8.5 kgf. The specification, function and features of the ultrasonic flaw detector, touch panel, gain setter, key board, microcomputer and others are reported. (Kako, I.)

  16. Fundamentals of Medical Ultrasonics

    CERN Document Server

    Postema, Michiel

    2011-01-01

    This book sets out the physical and engineering principles of acoustics and ultrasound as used for medical applications. It covers the basics of linear acoustics, wave propagation, non-linear acoustics, acoustic properties of tissue, transducer components, and ultrasonic imaging modes, as well as the most common diagnostic and therapeutic applications. It offers students and professionals in medical physics and engineering a detailed overview of the technical aspects of medical ultrasonic imaging, whilst serving as a reference for clinical and research staff.

  17. Assessing ultrasonic examination results

    International Nuclear Information System (INIS)

    Deutsch, V.; Vogt, M.

    1977-01-01

    Amongst nondestructive examination methods, the ultrasonic examination plays an important role. The reason why its scope of application is so wide is because the sound conducting capacity is the only property the material of a test specimen has to have. As the fields are so manifold, only main aspects can be described briefly. The list of references, however, is very extensive and gives plenty of information of all the problems concerning the assessment of ultrasonic examination results. (orig./RW) [de

  18. Ultrasonic viewing device

    International Nuclear Information System (INIS)

    Ito, Juro.

    1979-01-01

    Purpose: To improve the safety of reactor operation by enabling to detect the states and positions of fuel assemblies over a wide range with a set of ultrasonic viewing device comprising a rotatable ultrasonic transmitter-receiver and a reflector mounted with an adjustable angle. Constitution: A driving portion for a ultrasonic viewing device is provided to a rotary plug closing the opening of a reactor vessel and a guide pipe suspending below the coolant level is provided to the driving portion. An ultrasonic transmitter-receiver is provided at the end of the holder tube in the guide pipe. A reflector is provided at the upper position of the reactor core so as to correspond to the ultrasonic transmitter-receiver. The ultrasonic transmitter-receiver, positioned by the driving portion, performs horizontal movement for scanning the entire surface of the top of the reactor core, as well as vertical movement covering the gap between the upper mechanism on the reactor and the reactor core, whereby the confirmation for the separation of the control rod and the detection for the states of the reactor core can be conducted by the reflection waves from the reflector. (Moriyama, K.)

  19. ULTRASONIC ASSEMBLY [REVIEW

    Directory of Open Access Journals (Sweden)

    PORAV Viorica

    2015-05-01

    Full Text Available The paper exposes the possibility of machine producesers to optimize the costs of clothes assembling. Ultrasonic systems being frequently utilized have many advantages on semi products of synthetic textile and technical textile. First of all, sewing – cutting process can be accomplished under high speeds and rate of losses can be minimized. Cutting seal applications are frequently used for underwear and sportswear. Slicing and unit cutting machines, as well as portable sealing machines are available for labeling sector. Products such as bag, pocket and cover can be sewed in a seamless manner for promotion purposes. All objects in terms of accessories are obtained in same standard. Our quilting machines are preferred in worldwide due to its threadless, high quality sealing. An alternative to the classic sewing assembly, with thread and needles is ultrasonic seaming. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. Ultrasonic is defined as acoustic frequencies above the range audible to the human ear. Ultrasonic frequencies are administered to the fabric from the sonotrode of bonding machine. The high frequency and powerful energy produced, when is release in one special environment, the ultrasound heating this environment. The ability to ultrasonic weld textiles and films depend on their thermoplastic contents and the desired end results. The paper defines the weld ability of more common textiles and films. The welding refers to all types of bonding and sealing, as in point bonding of fabric, or continuous sealing of film.

  20. Vortex Ring Interaction With a Coaxially Aligned Cylinderical Rod

    Science.gov (United States)

    Arakeri, Jaywant H.; Rajmanoharan, P.; Koochesfahani, Manoochehr

    1998-11-01

    We present results of experiments of a fully developed vortex ring interacting with a cylinderical rod, having a rounded nose, placed coaxially in line with the motion of the ring. The pressure field of the translating ring causes unsteady boundary layer separation and results in the formation of one or more ( secondary ) vortex rings, that subsequently interact. The nature and strength of the interaction depends on the ratio of the cylinder diameter to the ring diameter. For the larger diameter cylinders the vortex ring travels a few ring diameters before it breaks up. For the smaller diameter cylinders the vortex ring speed decreases slowly and, simultaneously, its diameter increases.

  1. Donor-impurity related photoionization cross section in GaAs/Ga{sub 1−x}Al{sub x}As concentric double quantum rings: Effects of geometry and hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Baghramyan, H.M. [Department of Solid State Physics, Yerevan State University, Alex Manoogian 1, 0025 Yerevan (Armenia); Barseghyan, M.G., E-mail: mbarsegh@ysu.am [Department of Solid State Physics, Yerevan State University, Alex Manoogian 1, 0025 Yerevan (Armenia); Kirakosyan, A.A. [Department of Solid State Physics, Yerevan State University, Alex Manoogian 1, 0025 Yerevan (Armenia); Laroze, D. [Instituto de Alta Investigación, Universidad de Tarapacá, Casilla 7D, Arica (Chile); Duque, C.A. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia)

    2014-09-15

    The donor-impurity related photoionization cross section in GaAs/Ga{sub 1−x}Al{sub x}As three-dimensional concentric double quantum rings is investigated. The photoionization cross section dependence on the incident photon energy is studied considering the effects of hydrostatic pressure, variations of aluminum concentration, geometries of the structure, and impurity position. The interpretation of the dipole matrix element, which reflects the photoionization probability, is also given. We have found that these parameters can lead to both redshift and blueshift of the photoionization spectrum and also influence the cross section peak value.

  2. Dynamics of ultrasonic additive manufacturing.

    Science.gov (United States)

    Hehr, Adam; Dapino, Marcelo J

    2017-01-01

    Ultrasonic additive manufacturing (UAM) is a solid-state technology for joining similar and dissimilar metal foils near room temperature by scrubbing them together with ultrasonic vibrations under pressure. Structural dynamics of the welding assembly and work piece influence how energy is transferred during the process and ultimately, part quality. To understand the effect of structural dynamics during UAM, a linear time-invariant model is proposed to relate the inputs of shear force and electric current to resultant welder velocity and voltage. Measured frequency response and operating performance of the welder under no load is used to identify model parameters. Using this model and in-situ measurements, shear force and welder efficiency are estimated to be near 2000N and 80% when welding Al 6061-H18 weld foil, respectively. Shear force and welder efficiency have never been estimated before in UAM. The influence of processing conditions, i.e., welder amplitude, normal force, and weld speed, on shear force and welder efficiency are investigated. Welder velocity was found to strongly influence the shear force magnitude and efficiency while normal force and weld speed showed little to no influence. The proposed model is used to describe high frequency harmonic content in the velocity response of the welder during welding operations and coupling of the UAM build with the welder. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Investigation of the Influence of Sucrose and Cholesterol on the Phase Transition Temperature of nanoliposomal formulation besides using particle size Reduction Techniques (Ultrasonication/High Pressure Homogenization

    Directory of Open Access Journals (Sweden)

    Z Malaei-Balasi

    2017-05-01

    Full Text Available Introduction: The successful application of nanoliposoms as an effective drug delivery system depends on their stability in the medium. In this article, influence of additive materials such as cholesterol and sucrose besides two natural and synthesized phospholipids have been investigated. Methods: In the present study, designing and synthesis of nanoliposomal formulations were prepared using thin film method. This liposomal suspension was downsized by two methods, the high-pressure homogenizer and ultrasound to form small unilamellar vesicles. The size distributions, zeta potentials and phase transition temperature of formulations were all determined by a zetasizer and differential scanning calorimetry(DSC. In addition, the contribution of nanoliposomal formulation has been investigated by HPLC and FTIR methods. Results: Results of the DSC measurments indicated that incorporation of unsaturated phospholipid (SOY PC may cause phase separation with partial miscibility in the liposome bilayer containing of DPPG. The optimal nanoliposomal formulation was composed of (DPPC: CHOL: mPEG2000-DSPE with the mole percents equal to (83:15:2, respectively. In addition, sucrose has been used in the formulation with a total amounts six times greater than that of the lipids. The properties of optimized nanoliposome have been shown as the size average 104nm, zeta potential 8.04mv and phase transition temperature of lipid less than 37°C which were stable enough to be utilized for loading and releasing bioactives in body temperature. Conclusion: Finally the produced nanoliposomes were stable vesicles in the proper size, phase transition temperature and surface charge without any aggregation and fusion.

  4. Lower sintering temperature of nanostructured dense ceramics compacted from dry nanopowders using powerful ultrasonic action

    OpenAIRE

    Khasanov, O.; Reichel, U.; Dvilis, E.; Khasanov, A.

    2011-01-01

    Nanostructured high dense zirconia ceramics have been sintered from dry nanopowders compacted by uniaxial pressing with simultaneous powerful ultrasonic action (PUA). Powerful ultrasound with frequency of 21 kHz was supplied from ultrasonic generator to the mold, which was the ultrasonic wave-guide. Previously the mold was filled by non-agglomerated zirconia nanopowder having average particle size of 40 nm. Any binders or plasticizers were excluded at nanopowder processing. Compaction pressur...

  5. Ultrasonic dip seal maintenance system

    International Nuclear Information System (INIS)

    Poindexter, A.M.; Ricks, H.E.

    1978-01-01

    Disclosed is a system for removing impurities from the surfaces of liquid dip seals and for wetting the metal surfaces of liquid dip seals in nuclear components. The system comprises an ultrasonic transducer that transmits ultrasonic vibrations along an ultrasonic probe to the metal and liquid surfaces of the dip seal thereby loosening and removing those impurities

  6. Artificial Intelligence Assists Ultrasonic Inspection

    Science.gov (United States)

    Schaefer, Lloyd A.; Willenberg, James D.

    1992-01-01

    Subtle indications of flaws extracted from ultrasonic waveforms. Ultrasonic-inspection system uses artificial intelligence to help in identification of hidden flaws in electron-beam-welded castings. System involves application of flaw-classification logic to analysis of ultrasonic waveforms.

  7. Ultrasonic Stir Welding

    Science.gov (United States)

    Nabors, Sammy

    2015-01-01

    NASA Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process, improves current thermal stir welding processes by adding high-power ultrasonic (HPU) energy at 20 kHz frequency. The addition of ultrasonic energy significantly reduces axial, frictional, and shear forces; increases travel rates; and reduces wear on the stir rod, which results in extended stir rod life. The USW process decouples the heating, stirring, and forging elements found in the friction stir welding process allowing for independent control of each process element and, ultimately, greater process control and repeatability. Because of the independent control of USW process elements, closed-loop temperature control can be integrated into the system so that a constant weld nugget temperature can be maintained during welding.

  8. Ultrasonic nondestructive materials characterization

    Science.gov (United States)

    Green, R. E., Jr.

    1986-01-01

    A brief review of ultrasonic wave propagation in solid materials is presented with consideration of the altered behavior in anisotropic and nonlinear elastic materials in comparison with isotropic and linear elastic materials. Some experimental results are described in which ultrasonic velocity and attenuation measurements give insight into materials microstructure and associated mechanical properties. Recent developments with laser beam non-contact generation and detection of ultrasound are presented. The results of several years of experimental measurements using high-power ultrasound are discussed, which provide substantial evidence of the inability of presently accepted theories to fully explain the interaction of ultrasound with solid materials. Finally, a special synchrotron X-ray topographic system is described which affords the possibility of observing direct interaction of ultrasonic waves with the microstructural features of real crystalline solid materials for the first time.

  9. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  10. Ultrasonic tests. Pt. 2

    International Nuclear Information System (INIS)

    Goebbels, K.

    1980-01-01

    After a basic treatment of ultrasonic wave propagation, of the state-of-the-art methods and the technical background in the preceeding part, advanced ultrasonic NDT techniques are presented here. The discussion of new development includes - manipulation systems, - automation of ultrasonic testing methods, documentation and evaluation. In the middle of this part the main problem areas will be discussed: - detection of defects (e.g. in coarse grained structures and welds), - classification of defects (e.g. discrimination between crack-like and volumetric faults), - sizing of defects. Research in the field of acoustical holography, development of probes and phased arrays, electromagnetic acoustic transducers and signal enhancement are the main contributing parts to the report. (orig./RW)

  11. Ultrasonic control of ceramic membrane fouling by particles: effect of ultrasonic factors.

    Science.gov (United States)

    Chen, Dong; Weavers, Linda K; Walker, Harold W

    2006-07-01

    Ultrasound at 20 kHz was applied to a cross-flow ultrafiltration system with gamma-alumina membranes in the presence of colloidal silica particles to systematically investigate how ultrasonic factors affect membrane cleaning. Based on imaging of the ultrasonic cavitation region, optimal cleaning occurred when the membrane was outside but close to the cavitation region. Increasing the filtration pressure increased the compressive forces driving cavitation collapse and resulted in fewer cavitation bubbles absorbing and scattering sound waves and increasing sound wave penetration. However, an increased filtration pressure also resulted in greater permeation drag, and subsequently less improvement in permeate flux compared to low filtration pressure. Finally, pulsed ultrasound with short pulse intervals resulted in permeate flux improvement close to that of continuous sonication.

  12. Ultrasonic-resonator-combined apparatus for purifying nuclear aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Suxia; Zhang, Quanhu; Li, Sufen; Chen, Chen; Su, Xianghua [Xi' an Hi-Tech Institute, Xi' an (China)

    2017-12-15

    The radiation hazards of radionuclides in the air arising from the storage room of nuclear devices to the operators cannot be ignored. A new ultrasonic-resonator-combined method for purifying nuclear aerosol particles is introduced. To remove particles with diameters smaller than 0.3 μm, an ultrasonic chamber is induced to agglomerate these submicron particles. An apparatus which is used to purify the nuclear aerosol particles is described in the article. The apparatus consists of four main parts: two filtering systems, an ultrasonic chamber and a high-pressure electrostatic precipitator system. Finally, experimental results demonstrated the effectiveness of the implementation of the ultrasonic resonators. The feasibility of the method is proven by its application to the data analysis of the experiments.

  13. Study on the development of ultrasonic gas flowmeter

    International Nuclear Information System (INIS)

    Hwang, Won Ho; Park, Sang Gug; Yang, Kyu Hong; Jhang, Kyung Young

    2001-01-01

    Ultrasonic flowmeters have more advantages than the conventional method using pressure-difference. In these reasons, many advanced nations are already selling the commercial model. In RIST, we have been developed ultrasonic gas flow meter for the localization since a project was been contracted with POSCO in 1997. This paper describes a new ultrasonic gas flowmeter. This ultrasonic gas flowmeter is developed for accurate measurement of gases in a harsh environmental conditions. It is especially suited for measuring LDG, COG, BFG gases produced in iron and steel making process. In this study, we had developed the commercial model about the first tested model and applied a completed system to the POSCO gas line. Its performance has already well been proven by extensive field tests for several months in POSCO, iron and steel making company

  14. Ultrasonic weld testing.

    Science.gov (United States)

    1970-12-01

    The study was broken down into two phases. Phase I consisted of a laboratory investigation of test specimens to determine the reliability of the ultrasonic equipment and testing procedure. Phase II was a field study where the knowledge, skills and ab...

  15. Ultrasonic leak detection

    International Nuclear Information System (INIS)

    Murphy, R.V.

    1977-01-01

    A scanning ultrasonic microphone was used to detect the presence and locate the sources of hydraulic noises in piping systems in a reactor environment. The intensity changes of the noises correspond to changes of flow conditions within the system caused by throttled valves, flow rate changes, and leaks. (author)

  16. Donor impurity-related linear and nonlinear optical absorption coefficients in GaAs/Ga{sub 1−x}Al{sub x}As concentric double quantum rings: Effects of geometry, hydrostatic pressure, and aluminum concentration

    Energy Technology Data Exchange (ETDEWEB)

    Baghramyan, H.M.; Barseghyan, M.G.; Kirakosyan, A.A. [Department of Solid State Physics, Yerevan State University, Al. Manookian 1, 0025 Yerevan (Armenia); Restrepo, R.L. [Física Teórica y Aplicada, Escuela de Ingeniería de Antioquia, AA 7516, Medellín (Colombia); Grupo de Materia Condensada-UdeA, Instituto de Física, Facultadde Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21,Medellín (Colombia); Mora-Ramos, M.E. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultadde Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21,Medellín (Colombia); Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico); Duque, C.A., E-mail: cduque@fisica.udea.edu.co [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultadde Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21,Medellín (Colombia)

    2014-01-15

    The linear and nonlinear optical absorption associated with the transition between 1s and 2s states corresponding to the electron-donor-impurity complex in GaAs/Ga{sub 1−x}Al{sub x}As three-dimensional concentric double quantum rings are investigated. Taking into account the combined effects of hydrostatic pressure and the variation of the aluminum concentration, the energies of the ground and first excited s-like states of a donor impurity in such a system have been calculated using the effective mass approximation and a variational method. The energies of these states and the corresponding threshold energy of the optical transitions are examined as functions of hydrostatic pressure, aluminum concentration, radial impurity position, as well as the geometrical dimensions of the structure. The dependencies of the linear, nonlinear and total optical absorption coefficients as functions of the incident photon energy are investigated for different values of those mentioned parameters. It is found that the influences mentioned above lead to either redshifts or blueshifts of the resonant peaks of the optical absorption spectrum. It is particularly discussed the unusual property exhibited by the third-order nonlinear of becoming positive for photon energies below the resonant transition one. It is shown that this phenomenon is associated with the particular features of the system under study, which determine the values of the electric dipole moment matrix elements. -- Highlights: • Intra-band optical absorption associated to impurity states in double quantum rings. • Combined effects of hydrostatic pressure and aluminum concentration are studied. • The influences mentioned above lead to shifts of resonant peaks. • It is discussed an unusual property exhibited by the third-order nonlinear absorption.

  17. Donor impurity-related linear and nonlinear optical absorption coefficients in GaAs/Ga1−xAlxAs concentric double quantum rings: Effects of geometry, hydrostatic pressure, and aluminum concentration

    International Nuclear Information System (INIS)

    Baghramyan, H.M.; Barseghyan, M.G.; Kirakosyan, A.A.; Restrepo, R.L.; Mora-Ramos, M.E.; Duque, C.A.

    2014-01-01

    The linear and nonlinear optical absorption associated with the transition between 1s and 2s states corresponding to the electron-donor-impurity complex in GaAs/Ga 1−x Al x As three-dimensional concentric double quantum rings are investigated. Taking into account the combined effects of hydrostatic pressure and the variation of the aluminum concentration, the energies of the ground and first excited s-like states of a donor impurity in such a system have been calculated using the effective mass approximation and a variational method. The energies of these states and the corresponding threshold energy of the optical transitions are examined as functions of hydrostatic pressure, aluminum concentration, radial impurity position, as well as the geometrical dimensions of the structure. The dependencies of the linear, nonlinear and total optical absorption coefficients as functions of the incident photon energy are investigated for different values of those mentioned parameters. It is found that the influences mentioned above lead to either redshifts or blueshifts of the resonant peaks of the optical absorption spectrum. It is particularly discussed the unusual property exhibited by the third-order nonlinear of becoming positive for photon energies below the resonant transition one. It is shown that this phenomenon is associated with the particular features of the system under study, which determine the values of the electric dipole moment matrix elements. -- Highlights: • Intra-band optical absorption associated to impurity states in double quantum rings. • Combined effects of hydrostatic pressure and aluminum concentration are studied. • The influences mentioned above lead to shifts of resonant peaks. • It is discussed an unusual property exhibited by the third-order nonlinear absorption

  18. Design of Piston Ring Friction Tester Apparatus

    DEFF Research Database (Denmark)

    Klit, Peder

    2006-01-01

    One of the major prerequisites for calculating piston ring friction is a good description of the tribological situation. Piston rings operate in three different lubrication regimes and the theoretical models should be capable to describe this. A very important condition for describing the frictio......One of the major prerequisites for calculating piston ring friction is a good description of the tribological situation. Piston rings operate in three different lubrication regimes and the theoretical models should be capable to describe this. A very important condition for describing...... the frictional behavior of a piston ring correctly is knowledge about the amount of lubricant present. For piston rings the external load may be established by measuring the pressure distribution, i.e. the pressure drop in the piston ring package. Speed and temperature may also be established. The amount...... available is reflected in the friction absorbed in the bearing. The following properties will be measured: Oil fillm thickness - along liner (axial variation), oil film thickness - along piston ring (circumferential variation), piston tilt, temperature of piston rings and liner, pressure at piston lands...

  19. Ultrasonic Bat Deterrent Technology

    Energy Technology Data Exchange (ETDEWEB)

    Kinzie, Kevin; Rominger, Kathryn M.

    2017-12-14

    The project objective was to advance the development and testing of an Near commercial bat-deterrent system with a goal to increase the current GE deterrent system effectiveness to over 50% with broad species applicability. Additionally, the research supported by this program has provided insights into bat behavior and ultrasonic deterrent design that had not previously been explored. Prior research and development had demonstrated the effectiveness of a commercial-grade, air-powered, ultrasonic bat deterrent to be between 30-50% depending upon the species of bat. However, the previous research provided limited insight into the behavioral responses of bats in the presence of ultrasonic deterrent sound fields that could be utilized to improve effectiveness. A unique bat flight room was utilized to observe the behavioral characteristics of bats in the presence of ultrasonic sound fields. Behavioral testing in the bat flight facility demonstrated that ultrasonic sounds similar to those produced by the GE deterrent influenced the activities and behaviors, primarily those associated with foraging, of the species exposed. The study also indicated that continuous and pulsing ultrasonic signals had a similar effect on the bats, and confirmed that as ultrasonic sounds attenuate, their influence on the bats’ activities and behavior decreases. Ground testing at Wolf Ridge Wind, LLC and Shawnee National Forest assessed both continuous and pulsing deterrent signals emitted from the GE deterrent system and further enhanced the behavioral understanding of bats in the presence of the deterrent. With these data and observations, the existing 4-nozzle continuous, or steady, emission ultrasonic system was redesigned to a 6-nozzle system that could emit a pulsing signal covering a larger air space around a turbine. Twelve GE 1.6-100 turbines were outfitted with the deterrent system and a formal three-month field study was performed using daily carcass searches beneath the 12

  20. Ultrasonic signal processing for sizing under-clad flaws

    International Nuclear Information System (INIS)

    Shankar, R.; Paradiso, T.J.; Lane, S.S.; Quinn, J.R.

    1985-01-01

    Ultrasonic digital data were collected from underclad cracks in sample pressure vessel specimen blocks. These blocks were weld cladded under different processes to simulate actual conditions in US Pressure Water Reactors. Each crack was represented by a flaw-echo dynamic curve which is a plot of the transducer motion on the surface as a function of the ultrasonic response into the material. Crack depth sizing was performed by identifying in the dynamic curve the crack tip diffraction signals from the upper and lower tips. This paper describes the experimental procedure, digital signal processing methods used and algorithms developed for crack depth sizing

  1. Ozone production in a dielectric barrier discharge with ultrasonic irradiation

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Kusano, Yukihiro; Leipold, Frank

    2011-01-01

    Ozone production has been investigated using an atmospheric pressure dielectric barrier discharge in pure O2 at room temperature with and without ultrasonic irradiation. It was driven at a frequency of either 15 kHz or 40 kHz. The ozone production was highly dependent on the O2 flow rate and the ......Ozone production has been investigated using an atmospheric pressure dielectric barrier discharge in pure O2 at room temperature with and without ultrasonic irradiation. It was driven at a frequency of either 15 kHz or 40 kHz. The ozone production was highly dependent on the O2 flow rate...

  2. An inverse method for crack characterization from ultrasonic B-Scan images

    International Nuclear Information System (INIS)

    Faur, M.; Roy, O.; Benoist, PH.; Morisseau, PH.

    1996-01-01

    Concern has been expressed about the capabilities of performing non destructive evaluation (NDE) of flaws located near to the outer surface in nuclear pressurized water reactor (PWR) vessels. The ultrasonic examination of PWR is accomplished from the inside with ultrasonic focused transducers working in the pulse echo mode. By recording the echoes as a function of time, the Ascan representation may be obtained. Many ultrasonic flaw detectors used for NDE are based on the simple Ascan concept involving measuring a time interval called 'time of flight'. By combining the Ascan concept synchronized transducer scanning, one can produce Bscan images that are two dimensional descriptions of the flaw interaction with the ultrasonic field. In the following, the flaw is assumed to be an axially oriented crack (the most serious flaw to be found in a pressurized component). In the case of the outer surface cracks (OSC's), analyzing and interpreting ultrasonic Ascan images become difficult because of the various reflections of the ultrasonic beam on the crack and on the outer surface (the so-called corner effect). Methods for automatic interpretation of ultrasonic experimental data are currently under investigation. In this paper, we present an inverse method for determining the geometrical characteristics of OSC's from ultrasonic Bscan images. The direct model used for the inversion procedure predicts synthetic Bscan images of ultrasonic examination of blocks containing planar defects interrogated by focused probes. (authors)

  3. High pressure shaft seal

    International Nuclear Information System (INIS)

    Martinson, A.R.; Rogers, V.D.

    1980-01-01

    In relation to reactor primary coolant pumps, mechanical seal assembly for a pump shaft is disclosed which features a rotating seal ring mounting system which utilizes a rigid support ring loaded through narrow annular projections in combination with centering non-sealing O-rings which effectively isolate the rotating seal ring from temperature and pressure transients while securely positioning the ring to adjacent parts. A stationary seal ring mounting configuration allows the stationary seal ring freedom of motion to follow shaft axial movement up to 3/4 of an inch and shaft tilt about the pump axis without any change in the hydraulic or pressure loading on the stationary seal ring or its carrier. (author)

  4. Influence of fillers on hydrogen penetration properties and blister fracture of rubber composites for O-ring exposed to high-pressure hydrogen gas

    Energy Technology Data Exchange (ETDEWEB)

    Yamabe, Junichiro; Nishimura, Shin [Department of Mechanical Science Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Research Center for Hydrogen Industrial Use and Storage (HYDROGENIUS), National Institute of Advanced Industrial Science and Technology (AIST), 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

    2009-02-15

    Ethylene-propylene rubber (EPDM) and nitrile-butadiene rubber (NBR) composites having carbon black, silica, and no fillers were exposed to hydrogen gas at a maximum pressure of 10 MPa; then, blister tests and the measurement of hydrogen content were conducted. The hydrogen contents of the composites were proportional to the hydrogen pressure, i.e., the behavior of their hydrogen contents follows Henry's law. This implies that hydrogen penetrates into the composite as a hydrogen molecule. The addition of carbon black raised the hydrogen content of the composite, while the addition of silica did not. Based on observations, the blister damages of composites with silica were less pronounced, irrespective of the hydrogen pressures. This may be attributed to their lower hydrogen content and relatively better tensile properties than the others. (author)

  5. Kayser-Fleischer Rings

    Science.gov (United States)

    ... Support Contacts Lab Tracker/Copper Calculator Stories Programs & Research ... About Everything you need to know about Wilson Disease Kayser-Fleischer Rings Definition Kayser-Fleischer Ring: Clinical sign. Brownish-yellow ring visible around the corneo- ...

  6. NEET In-Pile Ultrasonic Sensor Enablement-Final Report

    Energy Technology Data Exchange (ETDEWEB)

    J. Daw; J. Rempe; J. Palmer; P. Ramuhalli; R. Montgomery; H.T. Chien; B. Tittmann; B. Reinhardt; P. Keller

    2014-09-01

    Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which is a collaborative effort between the Idaho National Laboratory, the Pacific Northwest National Laboratory, the Argonne National Laboratory, and the Pennsylvania State University. The objective of this report is to document the objectives and accomplishments from this three year project. As summarized within this document, significant work has been accomplished during this three year project.

  7. ASSOCIATIVE RINGS SOLVED AS LIE RINGS

    Directory of Open Access Journals (Sweden)

    M. B. Smirnov

    2011-01-01

    Full Text Available The paper has proved that an associative ring which is solvable of a n- class as a Lie ring has a nilpotent ideal of the nilpotent class not more than 3×10n–2  and a corresponding quotient ring satisfies an identity [[x1, x2, [x3, x4

  8. Ultrasonic calibration assembly

    International Nuclear Information System (INIS)

    1981-01-01

    Ultrasonic transducers for in-service inspection of nuclear reactor vessels have several problems associated with them which this invention seeks to overcome. The first is that of calibration or referencing a zero start point for the vertical axis of transducer movement to locate a weld defect. The second is that of verifying the positioning (vertically or at a predetermined angle). Thirdly there is the problem of ascertaining the speed per unit distance in the operating medium of the transducer beam prior to the actual inspection. The apparatus described is a calibration assembly which includes a fixed, generally spherical body having a surface for reflecting an ultrasonic beam from one of the transducers which can be moved until the reflection from the spherical body is the highest amplitude return signal indicating radial alignment from the body. (U.K.)

  9. Considerations for ultrasonic testing application for on-orbit NDE

    Science.gov (United States)

    Koshti, Ajay M.

    2015-04-01

    The paper addresses some on-orbit nondestructive evaluation (NDE) needs of NASA for International Space Station (ISS). The presentation gives NDE requirements for inspecting suspect damage due to micro-meteoroids and orbital debris (MMOD) impact on the pressure wall of the ISS. This inspection is meant to be conducted from inside of the ISS module. The metallic wall of the module has a fixed wall thickness but also has integral orthogrid ribs for reinforcement. Typically, a single MMOD hit causes localized damage in a small area causing loss of material similar to pitting corrosion, but cracks may be present too. The impact may cause bulging of the wall. Results of the ultrasonic and eddy current demonstration scans on test samples are provided. The ultrasonic technique uses shear wave scans to interrogate the localized damage area from the surrounding undamaged area. The scanning protocol results in multiple scans, each with multiple "vee" paths. A superimposition and mosaic of the three-dimensional ultrasonic data from individual scans is desired to create C-scan images of the damage. This is a new data reduction process which is not currently implemented in state-of-art ultrasonic instruments. Results of ultrasonic scans on the simulated MMOD damage test plates are provided. The individual C-scans are superimposed manually creating mosaic of the inspection. The resulting image is compared with visibly detected damage boundaries, X-ray images, and localized ultrasonic and eddy current scans for locating crack tips to assess effectiveness of the ultrasonic scanning. The paper also discusses developments needed in improving ergonomics of the ultrasonic testing for on-orbit applications.

  10. Nuclear Radiation Tolerance of Single Crystal Aluminum Nitride Ultrasonic Transducer

    Science.gov (United States)

    Reinhard, Brian; Tittmann, Bernhard R.; Suprock, Andrew

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models, (Rempe et al., 2011; Kazys et al., 2005). These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The irradiation is also supported by a multi-National Laboratory collaboration funded by the Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation (NEET ASI) program. The results from this irradiation, which started in February 2014, offer the potential to enable the development of novel radiation tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. Hence, results from this irradiation offer the potential to bridge the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the

  11. Pulsed ultrasonic stir welding system

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2013-01-01

    An ultrasonic stir welding system includes a welding head assembly having a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. During a welding operation, ultrasonic pulses are applied to the rod as it rotates about its longitudinal axis. The ultrasonic pulses are applied in such a way that they propagate parallel to the longitudinal axis of the rod.

  12. Evaluation of the effectiveness of the sealed double-ringed infiltrometers and the effects of changes in atmospheric pressure on hydraulic conductivity

    International Nuclear Information System (INIS)

    McMullin, S.R.

    1994-01-01

    The Savannah River Site (SRS) is currently evaluating some 40 hazardous and radioactive-waste sites for remediation. A remedial alternative under consideration is the closing of a waste site with a RCRA-style closure cap. The closure cap is a moisture barrier designed to inhibit the free flow of water downward into the buried wastes. When a remedial design is prepared, it is often necessary to test the cap materials to verify compliance with this recommended limit. Among the EPA-recommended test instruments is the sealed double-ring infiltrometer (SDRI). During recent testing at the Savannah River Site (SRS), six SDRI were installed and tested on a single kaolin clay cap. The purpose of this testing was to obtain a measure of the distribution of hydraulic conductivity across a model kaolin clay cap. The test results provide an evaluation of instrument performance and a measure of the repeatability of results. In addition, the testing identified variations in the unsaturated hydraulic conductivity. This paper presents an overview of the SDRI, the testing program at SRS, and an evaluation of the observations and test results

  13. Advanced Ultrasonic Tomograph of Children's Bones

    Science.gov (United States)

    Lasaygues, Philippe; Lefebvre, Jean-Pierre; Guillermin, Régine; Kaftandjian, Valérie; Berteau, Jean-Philippe; Pithioux, Martine; Petit, Philippe

    This study deals with the development of an experimental device for performing ultrasonic computed tomography (UCT) on bone in pediatric degrees. The children's bone tomographs obtained in this study, were based on the use of a multiplexed 2-D ring antenna (1 MHz and 3 MHz) designed for performing electronic and mechanical scanning. Although this approach is known to be a potentially valuable means of imaging objects with similar acoustical impedances, problems arise when quantitative images of more highly contrasted media such as bones are required. Various strategies and various mathematical procedures for modeling the wave propagation based on Born approximations have been developed at our laboratory, which are suitable for use with pediatric cases. Inversions of the experimental data obtained are presented.

  14. Ultrasonic level and temperature sensor for power reactor applications

    International Nuclear Information System (INIS)

    Dress, W.B.; Miller, G.N.

    1983-01-01

    An ultrasonic waveguide employing torsional and extensional acoustic waves has been developed for use as a level and temperature sensor in pressurized and boiling water nuclear power reactors. Features of the device include continuous measurement of level, density, and temperature producing a real-time profile of these parameters along a chosen path through the reactor vessel

  15. Acoustic streaming induced by an ultrasonically oscillating endodontic file

    NARCIS (Netherlands)

    Verhaagen, B.; Boutsioukis, C.; van der Sluis, L.W.M.; Versluis, M.

    2014-01-01

    Ultrasonically activated irrigation is an advanced dental technique for irrigation of the root canal system during a root canal treatment. The basic cleaning mechanism is a result of acoustic streaming induced by an oscillating file, leading to mixing of the irrigant and pressure and shear stresses

  16. Acoustic streaming induced by an ultrasonically oscillating endodontic file

    NARCIS (Netherlands)

    Verhaagen, B.; Boutsioukis, C.; van der Sluis, L. W. M.; Versluis, M.

    Ultrasonically activated irrigation is an advanced dental technique for irrigation of the root canal system during a root canal treatment. The basic cleaning mechanism is a result of acoustic streaming induced by an oscillating file, leading to mixing of the irrigant and pressure and shear stresses

  17. Note: Decoupling design for high frequency piezoelectric ultrasonic transducers with their clamping connections

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F. J., E-mail: wangfujun@tju.edu.cn; Liang, C. M.; Tian, Y. L.; Zhao, X. Y.; Zhang, D. W. [Tianjin Key Laboratory of Equipment Design and Manufacturing Technology, School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China); Zhang, H. J. [Tianjin Key Laboratory of Modern Mechatronics Equipment Technology, School of Mechanical Engineering, Tianjin Polytechnic University, Tianjin 300387 (China)

    2015-12-15

    This work presents the flexure-mechanism based decoupling design between high frequency piezoelectric ultrasonic transducers and their clamping connections to improve ultrasonic energy transmission efficiency. The ring, prismatic beam, and circular notched hinge based flanges were presented, and the crucial geometric dimensions of the transducers with the flexure decoupling flanges were determined. Finite element analysis (FEA) was carried out to investigate the dynamic characteristics of the transducers. Finally, experiments were conducted to examine and verify the effects of the proposed decoupling flanges. FEA and experimental results show that smaller frequency deviations and larger tip displacement amplitudes have been achieved by using the transducers with the flexure flanges compared with the transducer with a rigid ring-type flange, and thus the ultrasonic transmission efficiency can be improved through the flexure flanges.

  18. Hydrostatic Pressure and Built-In Electric Field Effects on the Donor Impurity States in Cylindrical Wurtzite GaN/AlxGa1−xN Quantum Rings

    Directory of Open Access Journals (Sweden)

    Guangxin Wang

    2015-01-01

    Full Text Available Within the framework of the effective mass approximation, the ground-state binding energy of a hydrogenic impurity is investigated in cylindrical wurtzite GaN/AlxGa1-xN strained quantum ring (QR by means of a variational approach, considering the influence of the applied hydrostatic pressure along the QR growth direction and the strong built-in electric field (BEF due to the piezoelectricity and spontaneous polarization. Numerical results show that the donor binding energy for a central impurity increases inchmeal firstly as the QR radial thickness (ΔR decreases gradually and then begins to drop quickly. In addition, the donor binding energy is an increasing (a decreasing function of the inner radius (height. It is also found that the donor binding energy increases almost linearly with the increment of the applied hydrostatic pressure. Moreover, we also found that impurity positions have an important influence on the donor binding energy. The physical reasons have been analyzed in detail.

  19. Updated Results of Ultrasonic Transducer Irradiation Test

    Energy Technology Data Exchange (ETDEWEB)

    Daw, Joshua; Palmer, Joe [Idaho National Laboratory, P.O. Box 1625, MS 4112, Idaho Falls, ID, 38415-3840 (United States); Ramuhalli, Pradeep; Keller, Paul; Montgomery, Robert [Pacific Northwest National Laboratory, 902 Battelle Blvd. Richland, WA, 99354 (United States); Chien, Hual-Te [Argonne National Laboratory, 9700 S. Cass Avenue Argonne, IL, 60439 (United States); Tittmann, Bernhard; Reinhardt, Brian [Pennsylvania State University, 212 Earth and Engr. Sciences Building, University Park, PA, 16802 (United States); Kohse, Gordon [Massachusetts Institute of Technology, 77 Massachusetts Ave. Cambridge, MA 02139 (United States); Rempe, Joy [Rempe and Associates, LLC, 360 Stillwater, Idaho Falls, ID 83404 (United States); Villard, J.F. [Commissariat a l' energie atomique et aux energies alternatives, Centre d' etudes de Cadarache, 13108 Saint-Paul-lez-Durance (France)

    2015-07-01

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 10{sup 21} n/cm{sup 2}. A multi-National Laboratory collaboration funded by the Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation (NEET-ASI) program also provided initial support for this effort. This irradiation, which started in February 2014, is an instrumented lead test and real-time transducer performance data are collected along with temperature and neutron and gamma flux data. The irradiation is ongoing and will continue to approximately mid-2015. To date, very encouraging results have been attained as several transducers continue to operate under irradiation. (authors)

  20. Dog-Bone Horns for Piezoelectric Ultrasonic/Sonic Actuators

    Science.gov (United States)

    Sherrit, Stewart; Bar-Cohen, Yoseph; Chang, Zensheu; Bao, Xiaoqi

    2007-01-01

    A shape reminiscent of a dog bone has been found to be superior to other shapes for mechanical-amplification horns that are components of piezoelectrically driven actuators used in a series of related devices denoted generally as ultrasonic/sonic drill/corers (USDCs). The first of these devices was reported in Ultrasonic/Sonic Drill/Corers With Integrated Sensors (NPO-20856), NASA Tech Briefs, Vol. 25, No. 1 (January 2001), page 38. The dog-bone shape was conceived especially for use in a more recent device in the series, denoted an ultrasonic/ sonic gopher, that was described in Ultrasonic/Sonic Mechanisms for Drilling and Coring (NPO-30291), NASA Tech Briefs, Vol. 27, No. 9 (September 2003), page 65. The figure shows an example of a dog-bone-shaped horn and other components of an ultrasonic gopher. Prerequisite to a meaningful description of this development is an unavoidably lengthy recapitulation of the principle of operation of a USDC and, more specifically, of the ultrasonic/sonic gopher as described previously in NASA Tech Briefs. The ultrasonic actuator includes a stack of piezoelectric rings, the horn, a metal backing, and a bolt that connects the aforementioned parts and provides compressive pre-strain to the piezoelectric stack to prevent breakage of the rings during extension. The stack of piezoelectric rings is excited at the resonance frequency of the overall ultrasonic actuator. Through mechanical amplification by the horn, the displacement in the ultrasonic vibration reaches tens of microns at the tip of the horn. The horn hammers an object that is denoted the free mass because it is free to move longitudinally over a limited distance between hard stops: The free mass bounces back and forth between the ultrasonic horn and a tool bit (a drill bit or a corer). Because the longitudinal speed of the free mass is smaller than the longitudinal speed of vibration of the tip of the horn, contact between the free mass and the horn tip usually occurs at a

  1. Alternative loop rings

    CERN Document Server

    Goodaire, EG; Polcino Milies, C

    1996-01-01

    For the past ten years, alternative loop rings have intrigued mathematicians from a wide cross-section of modern algebra. As a consequence, the theory of alternative loop rings has grown tremendously. One of the main developments is the complete characterization of loops which have an alternative but not associative, loop ring. Furthermore, there is a very close relationship between the algebraic structures of loop rings and of group rings over 2-groups. Another major topic of research is the study of the unit loop of the integral loop ring. Here the interaction between loop rings and group ri

  2. Ultrasonic attenuation in superconducting zinc

    International Nuclear Information System (INIS)

    Auluck, S.

    1978-01-01

    The differences in the Zn ultrasonic attenuation data of different workers are analyzed. The superconducting energy gaps deduced from our analysis of the ultrasonic-attenuation data of Cleavelin and Marshall are consistent with the gaps deduced from the knowledge of the Fermi surface and the electron-phonon mass enhancement factor

  3. Lumber defect detection by ultrasonics

    Science.gov (United States)

    K. A. McDonald

    1978-01-01

    Ultrasonics, the technology of high-frequency sound, has been developed as a viable means for locating most defects In lumber for use in digital form in decision-making computers. Ultrasonics has the potential for locating surface and internal defects in lumber of all species, green or dry, and rough sawn or surfaced.

  4. Ultrasonic inspection of austenitic welds

    International Nuclear Information System (INIS)

    Baikie, B.L.; Wagg, A.R.; Whittle, M.J.; Yapp, D.

    1976-01-01

    The ultrasonic examination of austenitic stainless steel weld metal has always been regarded as a difficult proposition because of the large and variable ultrasonic attenuations and back scattering obtained from apparently similar weld deposits. The work to be described shows how the existence of a fibre texture within each weld deposit (as a result of epitaxial growth through successive weld beads) produces a systematic variation in the ultrasonic attenuation coefficient and the velocity of sound, depending upon the angle between the ultrasonic beam and the fibre axis. Development work has shown that it is possible to adjust the welding parameters to ensure that the crystallographic texture within each weld is compatible with improved ultrasonic transmission. The application of the results to the inspection of a specific weld in type 316 weld metal is described

  5. Development status of ultrasonic test techniques for cast stainless steel

    International Nuclear Information System (INIS)

    Nishikawa, Yoshito

    2015-01-01

    Ultrasonic testing has been thought to be difficult to apply to cast stainless steel which is used as the material for the main coolant pipes in pressurized water reactors (PWRs). An ultrasonic testing technique using large aperture twin crystal transducers was developed in INSS for application to inspection of the main coolant pipes. The method was evaluated in an application to detect circumferential and axial defects in the cast stainless steel pipes. It was found that (1) the defects could be detected which had a depth that was so small that their evaluation was not required; and (2) depth sizing and length sizing of detected defects were also possible. (author)

  6. Ultrasonic variables affecting inspection

    International Nuclear Information System (INIS)

    Lautzenheiser, C.E.; Whiting, A.R.; McElroy, J.T.

    1977-01-01

    There are many variables which affect the detection of the effects and reproducibility of results when utilizing ultrasonic techniques. The most important variable is the procedure, as this document specifies, to a great extent, the controls that are exercised over the other variables. The most important variable is personnel with regards to training, qualification, integrity, data recording, and data analysis. Although the data is very limited, these data indicate that, if the procedure is carefully controlled, reliability of defect detection and reproducibility of results are both approximately 90 percent for reliability of detection, this applies to relatively small defects as reliability increases substantially as defect size increases above the recording limit. (author)

  7. Wear Analysis of Top Piston Ring to Reduce Top Ring Reversal Bore Wear

    Directory of Open Access Journals (Sweden)

    P. Ilanthirayan

    2017-12-01

    Full Text Available The piston rings are the most important part in engine which controls the lubricating oil consumption and blowby of the gases. The lubricating film of oil is provided to seal of gases towards crankcase and also to give smooth friction free translatory motion between rings and liner. Of the three rings present top ring is more crucial as it does the main work of restricting gases downwards the crankcase. Boundary lubrication is present at the Top dead centre (TDC and Bottom dead centre (BDC of the liner surface. In addition to this, top ring is exposed to high temperature gases which makes the oil present near the top ring to get evaporated and decreasing its viscosity, making metal-metal contact most of the time. Due to this at TDC, excess wear happens on the liner which is termed as Top ring reversal bore wear. The wear rate depends upon many parameters such as lubrication condition, viscosity index, contact type, normal forces acting on ring, geometry of ring face, surface roughness, material property. The present work explores the wear depth for different geometries of barrel ring using Finite Element model with the help of Archard wear law and the same is validated through experimentation. The study reveals that Asymmetric barrel rings have less contact pressure which in turn reduces the wear at Top dead centre.

  8. Validation of Sizewell ''B'' ultrasonic inspections -- Messages for performance demonstration

    International Nuclear Information System (INIS)

    Conroy, P.J.; Leyland, K.S.; Waites, C.

    1994-01-01

    At the time that the decisions leading to the construction of the Sizewell ''B'' plant were being made, public concern over the potential hazards of nuclear power was increasing. This concern was heightened by the accident at USA's Three Mile Island plant. The result of this and public pressure was that an extensive public inquiry was held in addition to the UK's normal licensing process. Part of the evidence to the inquiry supporting the safety case relied upon the ability of ultrasonic inspections to demonstrate that the Reactor Pressure Vessel (RPV) and other key components were free from defects that could threaten structural integrity. Evidence from a variety of trials designed to investigate the performance capability of ultrasonic inspection revealed that although ultrasonic inspection had the potential to satisfy this requirement its performance in practice was heavily dependent upon the details of application. It was therefore generally recognized that some form of inspection validation was required to provide assurance that the equipment, procedures and operators to be employed were adequate for purpose. The concept of inspection validation was therefore included in the safety case for the licensing of Sizewell ''B''. The UK validation trials covering the ultrasonic inspections of the Sizewell ''B'' PWR Reactor Pressure Vessel are now nearing completion. This paper summarizes the results of the RPV validations and considers some of the implications for ASME 11 Appendix 8 the US code covering performance demonstration

  9. A study on Computer-controlled Ultrasonic Scanning Device

    International Nuclear Information System (INIS)

    Huh, H.; Park, C. S.; Hong, S. S.; Park, J. H.

    1989-01-01

    Since the nuclear power plants in Korea have been operated in 1979, the nondestructive testing (NDT) of pressure vessels and/or piping welds plays an important role for maintaining the safety and integrity of the plants. Ultrasonic method is superior to the other NDT method in the viewpoint of the detectability of small flaw and accuracy to determine the locations, sizes, orientations, and shapes. As the service time of the nuclear power plants is increased, the radiation level from the components is getting higher. In order to get more quantitative and reliable results and secure the inspector from the exposure to high radiation level, automation of the ultrasonic equipment has been one of the important research and development(R and D) subject. In this research, it was attempted to visualize the shape of flaws presented inside the specimen using a Modified C-Scan technique. In order to develop Modified C-Scan technique, an automatic ultrasonic scanner and a module to control the scanner were designed and fabricated. IBM-PC/XT was interfaced to the module to control the scanner. Analog signals from the SONIC MARK II were digitized by Analog-Digital Converter(ADC 0800) for Modified C-Scan display. A computer program has been developed and has capability of automatic data acquisition and processing from the digital data, which consist of maximum amplitudes in each gate range and locations. The data from Modified C-Scan results was compared with shape from artificial defects using the developed system. Focal length of focused transducer was measured. The automatic ultrasonic equipment developed through this study is essential for more accurate, reliable, and repeatable ultrasonic experiments. If the scanner are modified to meet to appropriate purposes, it can be applied to automation of ultrasonic examination of nuclear power plants and helpful to the research on ultrasonic characterization of the materials

  10. System for ultrasonic examination

    International Nuclear Information System (INIS)

    Lund, S.A.; Kristensen, W.D.

    1987-01-01

    A computerized system for the recording of flaw images by ultrasonic examination according to the pulse-echo method includes at least one ultrasonic probe which can be moved in steps over the surface of an object along a rectilinear scanning path. Digital signals containing information on the successive positions of the sound beam, on echo amplitudes, and on the lengths of sound paths to reflectors inside the object, are processed and used for the accumulated storage of circular patterns of echo amplitude data in a matrix memory associated with a sectional plane through the object. A video screen terminal controls the system and transforms the accumulated data into displays of sectional flaw images of greatly improved precision and sharpness of definition. A gradual transfer of filtered data from a number of parallel sectional planes to three further matrix memories associated with projection planes at right angles to each other permits presentation in three dimensions of equally improved projection flaw images. (author) 2 figs

  11. A study on the repeatability of ultrasonic testing data

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Fukumoto, Hiroshi

    1980-01-01

    Reliability improvement of ultrasonic testing data is strongly desired in ultrasonic testing working of nuclear power plants. This paper deals with the problems of the testing by the manual and the remote control apparatus, and with the factors which influence the repeatability of ultrasonic testing data. Following results are found in it. (1) In the testing by the manual, working time and posture influence the repeatability of testing data. (2) Glycerin in suitable for the couplant in the respect of the repeatability of testing data. In the case of using machine oil, the pressure to the probe necessitates to be over 0.2 kg/cm 2 . (3) In the testing by the remote control apparatus, working time, working environment and defect position does not influence the repeatability of testing data. (author)

  12. Ultrasound enhanced plasma surface modification at atmospheric pressure

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Norrman, Kion

    2012-01-01

    Efficiency of atmospheric pressure plasma treatment can be highly enhanced by simultaneous high power ultrasonic irradiation onto the treating surface. It is because ultrasonic waves with a sound pressure level (SPL) above ∼140 dB can reduce the thickness of a boundary gas layer between the plasma...... arc at atmospheric pressure to study adhesion improvement. The effect of ultrasonic irradiation with the frequency diapason between 20 and 40 kHz at the SPL of ∼150 dB was investigated. After the plasma treatment without ultrasonic irradiation, the wettability was significantly improved...

  13. Experimental Investigation on the Material Removal of the Ultrasonic Vibration Assisted Abrasive Water Jet Machining Ceramics

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2017-01-01

    Full Text Available The ultrasonic vibration activated in the abrasive water jet nozzle is used to enhance the capability of the abrasive water jet machinery. The experiment devices of the ultrasonic vibration assisted abrasive water jet are established; they are composed of the ultrasonic vibration producing device, the abrasive supplying device, the abrasive water jet nozzle, the water jet intensifier pump, and so on. And the effect of process parameters such as the vibration amplitude, the system working pressure, the stand-off, and the abrasive diameter on the ceramics material removal is studied. The experimental result indicates that the depth and the volume removal are increased when the ultrasonic vibration is added on abrasive water jet. With the increase of vibration amplitude, the depth and the volume of material removal are also increased. The other parameters of the ultrasonic vibration assisted abrasive water jet also have an important role in the improvement of ceramic material erosion efficiency.

  14. Influence on ultrasonic incident angle and defect detection sensitivity by cast stainless steel structure

    International Nuclear Information System (INIS)

    Kurozumi, Y.

    2004-01-01

    It is well known that ultrasonic waves are affected strongly by macro-structures in cast stainless steel, as in the primary pipe or other components in pressurized water reactors (PWRs). In this work, ultrasonic refractive angles and defect detection sensitivities are investigated at different incident angles to cast stainless steel. The aims of the investigation are to clarify the transmission of ultrasonic waves in cast stainless steel and to contribute to the transducer design. The results are that ultrasonic refractive angles in cast stainless steel shift towards the 45-degree direction with respect to the direction of dendritic structures by 11.8 degrees at the maximum and that the sensitivity of transducer for inner surface breaking cracks increases with decreasing incident angle. However, in an ultrasonic inspection of actual welds at smaller incident angles, a trade-off occurs between increased defect detection sensitivity and decreased defect discrimination capability due to intense false signals produced by non-defective features. (orig.)

  15. Imaging techniques for ultrasonic testing

    International Nuclear Information System (INIS)

    2013-01-01

    These seminar proceedings contain 16 lectures on the following topics: 1. From imaging to quantification - ultrasound methods in medical diagnostics; 2. SAFT, TOFD, Phased Array - classical applications and recent developments in ultrasonic imaging; 3. Innovative ultrasonic imaging methods in research and application; 4. Industrial ultrasonic testing of fibre-reinforced structures of complex geometry; 5. Visualisation of crack tips in the inspection of wheel set shafts with longitudinal boreholes as a means of avoiding unnecessary wheel set changes; 6. Areal analysis of the propagation of Lamb waves on curved, anisotropic structures; 7. High-resolution representation in immersion technique testing; 8. Variants in generating images from phased array measurement data - practical examples involving copper, carbon-fibre reinforced plastic and other materials; 9. GIUM - an unconventional method of microstructure imaging using ultrasonic stimulation and laser vibrometry scanning; 10. Innovative air-ultrasonic testing concepts for improved imaging; 11. Use of imaging methods for improving the quality of test results from nondestructive testing; 12. Modelling and visualisation of EMUS stimulation for transducer optimisation; 13. Use of SAFT in the manufacture of energy conversion machines; 14. Ultrasonic imaging tests for improved defect characterisation during weld seam inspection on longitudinally welded large-diameter pipes; 15. SAFT reconstruction for testing austenitic weld seams and dissimilar metal weld seams for transverse cracks; 16. Imaging-based optimisation method for quantitative ultrasonic testing of anisotropic inhomogeneous austenitic welded joints with determination and utilisation of their elastic properties. One contribution has been abstracted separately. [de

  16. Volumetric Real-Time Imaging Using a CMUT Ring Array

    OpenAIRE

    Choe, Jung Woo; Oralkan, Ömer; Nikoozadeh, Amin; Gencel, Mustafa; Stephens, Douglas N.; O’Donnell, Matthew; Sahn, David J.; Khuri-Yakub, Butrus T.

    2012-01-01

    A ring array provides a very suitable geometry for forward-looking volumetric intracardiac and intravascular ultrasound imaging. We fabricated an annular 64-element capacitive micromachined ultrasonic transducer (CMUT) array featuring a 10-MHz operating frequency and a 1.27-mm outer radius. A custom software suite was developed to run on a PC-based imaging system for real-time imaging using this device.

  17. Pulsed ultrasonic stir welding method

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2013-01-01

    A method of performing ultrasonic stir welding uses a welding head assembly to include a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. In the method, the rod is rotated about its longitudinal axis during a welding operation. During the welding operation, a series of on-off ultrasonic pulses are applied to the rod such that they propagate parallel to the rod's longitudinal axis. At least a pulse rate associated with the on-off ultrasonic pulses is controlled.

  18. Fundamentals of ultrasonic phased arrays

    CERN Document Server

    Schmerr, Lester W

    2014-01-01

    This book describes in detail the physical and mathematical foundations of ultrasonic phased array measurements.?The book uses linear systems theory to develop a comprehensive model of the signals and images that can be formed with phased arrays. Engineers working in the field of ultrasonic nondestructive evaluation (NDE) will find in this approach a wealth of information on how to design, optimize and interpret ultrasonic inspections with phased arrays. The fundamentals and models described in the book will also be of significant interest to other fields, including the medical ultrasound and

  19. Rings in drugs.

    Science.gov (United States)

    Taylor, Richard D; MacCoss, Malcolm; Lawson, Alastair D G

    2014-07-24

    We have analyzed the rings, ring systems, and frameworks in drugs listed in the FDA Orange Book to understand the frequency, timelines, molecular property space, and the application of these rings in different therapeutic areas and target classes. This analysis shows that there are only 351 ring systems and 1197 frameworks in drugs that came onto the market before 2013. Furthermore, on average six new ring systems enter drug space each year and approximately 28% of new drugs contain a new ring system. Moreover, it is very unusual for a drug to contain more than one new ring system and the majority of the most frequently used ring systems (83%) were first used in drugs developed prior to 1983. These observations give insight into the chemical novelty of drugs and potentially efficient ways to assess compound libraries and develop compounds from hit identification to lead optimization and beyond.

  20. Birth Control Ring

    Science.gov (United States)

    ... Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Birth Control Ring KidsHealth / For Teens / Birth Control Ring What's ...

  1. Computer automation of ultrasonic testing. [inspection of ultrasonic welding

    Science.gov (United States)

    Yee, B. G. W.; Kerlin, E. E.; Gardner, A. H.; Dunmyer, D.; Wells, T. G.; Robinson, A. R.; Kunselman, J. S.; Walker, T. C.

    1974-01-01

    Report describes a prototype computer-automated ultrasonic system developed for the inspection of weldments. This system can be operated in three modes: manual, automatic, and computer-controlled. In the computer-controlled mode, the system will automatically acquire, process, analyze, store, and display ultrasonic inspection data in real-time. Flaw size (in cross-section), location (depth), and type (porosity-like or crack-like) can be automatically discerned and displayed. The results and pertinent parameters are recorded.

  2. Integral Ring Carbon-Carbon Piston

    Science.gov (United States)

    Northam, G. Burton (Inventor)

    1999-01-01

    An improved structure for a reciprocating internal combustion engine or compressor piston fabricate from carbon-carbon composite materials is disclosed. An integral ring carbon-carbon composite piston, disclosed herein, reduces the need for piston rings and for small clearances by providing a small flexible, integral component around the piston that allows for variation in clearance due to manufacturing tolerances, distortion due to pressure and thermal loads, and variations in thermal expansion differences between the piston and cylinder liner.

  3. Study on the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration

    International Nuclear Information System (INIS)

    Lin Shuyu; Tian Hua

    2008-01-01

    A sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is studied. The transducer consists of front and back metal masses, and coaxially segmented, thickness polarized piezoelectric ceramic thin rings. For this kind of sandwich piezoelectric transducers in thickness vibration, it is required that the lateral dimension of the transducer is sufficiently large compared with its longitudinal dimension so that no lateral displacements in the transducer can occur (laterally clamped). In this paper, the thickness vibration of the piezoelectric ceramic stack consisting of a number of identical piezoelectric ceramic thin rings is analysed and its electro-mechanical equivalent circuit is obtained. The resonance frequency equation for the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is derived. Based on the frequency equation, two sandwich piezoelectric ceramic ultrasonic transducers are designed and manufactured, and their resonance frequencies are measured. It is shown that the measured resonance frequencies are in good agreement with the theoretical results. This kind of sandwich piezoelectric ultrasonic transducer is expected to be used in megasonic ultrasonic cleaning and sonochemistry where high power and high frequency ultrasound is needed

  4. The cavitation erosion of ultrasonic sonotrode during large-scale metallic casting: Experiment and simulation.

    Science.gov (United States)

    Tian, Yang; Liu, Zhilin; Li, Xiaoqian; Zhang, Lihua; Li, Ruiqing; Jiang, Ripeng; Dong, Fang

    2018-05-01

    Ultrasonic sonotrodes play an essential role in transmitting power ultrasound into the large-scale metallic casting. However, cavitation erosion considerably impairs the in-service performance of ultrasonic sonotrodes, leading to marginal microstructural refinement. In this work, the cavitation erosion behaviour of ultrasonic sonotrodes in large-scale castings was explored using the industry-level experiments of Al alloy cylindrical ingots (i.e. 630 mm in diameter and 6000 mm in length). When introducing power ultrasound, severe cavitation erosion was found to reproducibly occur at some specific positions on ultrasonic sonotrodes. However, there is no cavitation erosion present on the ultrasonic sonotrodes that were not driven by electric generator. Vibratory examination showed cavitation erosion depended on the vibration state of ultrasonic sonotrodes. Moreover, a finite element (FE) model was developed to simulate the evolution and distribution of acoustic pressure in 3-D solidification volume. FE simulation results confirmed that significant dynamic interaction between sonotrodes and melts only happened at some specific positions corresponding to severe cavitation erosion. This work will allow for developing more advanced ultrasonic sonotrodes with better cavitation erosion-resistance, in particular for large-scale castings, from the perspectives of ultrasonic physics and mechanical design. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Groups, rings, modules

    CERN Document Server

    Auslander, Maurice

    2014-01-01

    This classic monograph is geared toward advanced undergraduates and graduate students. The treatment presupposes some familiarity with sets, groups, rings, and vector spaces. The four-part approach begins with examinations of sets and maps, monoids and groups, categories, and rings. The second part explores unique factorization domains, general module theory, semisimple rings and modules, and Artinian rings. Part three's topics include localization and tensor products, principal ideal domains, and applications of fundamental theorem. The fourth and final part covers algebraic field extensions

  6. Ultrasonic velocity measurements in expanded liquid mercury

    International Nuclear Information System (INIS)

    Suzuki, K.; Inutake, M.; Fujiwaka, S.

    1977-10-01

    In this paper we present the first results of the sound velocity measurements in expanded liquid mercury. The measurements were made at temperatures up to 1600 0 C and pressures up to 1700 kg/cm 2 by means of an ultrasonic pulse transmission/echo technique which was newly developed for such high temperature/pressure condition. When the density is larger than 9 g/cm 3 , the observed sound velocity decreases linearly with decreasing density. At densities smaller than 9 g/cm 3 , the linear dependence on the density is no longer observed. The observed sound velocity approaches a minimum near the liquid-gas critical point (rho sub(cr) asymptotically equals 5.5 g/cm 3 ). The existing theories for sound velocity in liquid metals fail to explain the observed results. (auth.)

  7. Apparatus for ultrasonic nebulization

    International Nuclear Information System (INIS)

    Olson, K.W.; Haas, W.J. Jr.; Fassel, V.A.

    1978-01-01

    An improved apparatus is described for ultrasonic nebulization of liquid samples or suspensions in which the piezoelectric transducer is protected from chemical attack and erosion. The transducer is protected by being bonded to the inner surface of a glass plate which forms one end wall of a first hollow body provided with apparatus for circulating a fluid for cooling and stabilizing the transducer. The glass plate, which is one-half wavelength in thickness to provide an acoustically coupled outer nebulizing surface, seals an opening in a second hollow body which encloses an aerosol mixing chamber. The second body includes apparatus for delivering the sample solution to the nebulizing surface, a gas inlet for providing a flow of carrier gas for transporting the aerosol of the nebulized sample and an aerosol outlet

  8. High resolution ultrasonic densitometer

    International Nuclear Information System (INIS)

    Dress, W.B.

    1983-01-01

    The velocity of torsional stress pulses in an ultrasonic waveguide of non-circular cross section is affected by the temperature and density of the surrounding medium. Measurement of the transit times of acoustic echoes from the ends of a sensor section are interpreted as level, density, and temperature of the fluid environment surrounding that section. This paper examines methods of making these measurements to obtain high resolution, temperature-corrected absolute and relative density and level determinations of the fluid. Possible applications include on-line process monitoring, a hand-held density probe for battery charge state indication, and precise inventory control for such diverse fluids as uranium salt solutions in accountability storage and gasoline in service station storage tanks

  9. Ultrasonic imaging in concrete

    International Nuclear Information System (INIS)

    Ribay, G.; Paris, O.; Rambach, J.M.

    2009-01-01

    The third and final protection barrier confining nuclear reactors is usually a concrete containment structure. Monitoring the structural integrity of these barriers is critical in ensuring the safety of nuclear power plants. The Institute for Radiological Protection and Nuclear Safety (IRSN) in France in collaboration with the French Atomic commission (CEA/LIST) has developed an ultrasonic phased-array technique capable of inspecting thick concrete walls. The non-destructive method is dedicated to detect cracks and bulk defects. Given the thickness of the structure (1.2 m) undergoing inspection and the heterogeneity of the concrete, the optimal frequency lies in the 50-300 kHz range. At these frequencies, the ultrasonic beam profiles are widespread (non-directive) with poor signal-to-noise ratio. Previous studies have shown the potential of using phased-array techniques (i.e., beam focusing and beam steering) in order to improve detection resolution and sizing accuracy. In this paper we present experimental studies performed with array up to 16 transducers working at 200 kHz. Experiments are carried out on representative concrete blocks containing artificial defects. One is a reinforced mock-up representative of the first reinforcing mesh of wall containment. Experimental results show that in spite of the reinforcement, artificial defects deep as half a meter can be detected. Reconstructed images resulting from phased array acquisitions on an artificial crack embedded in a concrete block are also presented and discussed. The presented method allows detecting oriented defects in concrete with improved signal to noise ratio and sensibility. A simulation model of the interaction of ultrasound with a heterogeneous medium like concrete is briefly commented. (authors)

  10. Ultrasonic Technology in Duress Alarms.

    Science.gov (United States)

    Lee, Martha A.

    2000-01-01

    Provides the pros and cons of the most commonly used technologies in personal duress alarm systems in the school environment. Discussed are radio frequency devices, infrared systems, and ultrasonic technology. (GR)

  11. Ultrasonic extensometer measures bolt preload

    Science.gov (United States)

    Daniels, C. M., Jr.

    1978-01-01

    Extensometer using ultrasonic pulse reflections to measure elongations in tightened belts and studs is much more accurate than conventional torque wrenches in application of specified preload to bolts and other threaded fasteners.

  12. Ultrasonic Welding of Thin Alumina and Aluminum Using Inserts

    Science.gov (United States)

    Ishikuro, Tomoaki; Matsuoka, Shin-Ichi

    This paper describes an experimental study of ultrasonic welding of thin ceramics and metals using inserts. Ultrasonic welding has enable the joining of various thick ceramics, such as Al2O3 and ZrO2, to aluminum at room temperature quickly and easily as compared to other welding methods. However, for thin ceramics, which are brittle, welding is difficult to perform without causing damage. In this study, aluminum anodized oxide with different anodizing time was used as thin alumina ceramic. Vapor deposition of aluminum alloys was used to create an effective binder layer for welding at a low pressure and within a short duration in order to prevent damage to the anodic oxide film formed with a short anodizing time. For example, ultrasonic welding of thin Al2O3/Al was accomplished under the following conditions: ultrasonic horn tip amplitude of 30µm, welding pressure of 5MPa, and required duration of 0.1s. However, since the vapor deposition film tends to exfoliate as observed in the anodic oxide film formed with a long anodizing time, welding was difficult.

  13. Measurement of flaw size in a weld sample by ultrasonic frequency analysis

    International Nuclear Information System (INIS)

    Whaley, H.L. Jr.; Adler, L.; Cook, K.V.; McClung, R.W.

    1975-05-01

    An ultrasonic frequency analysis technique has been developed and applied to the measurement of flaws in an 8-in.-thick heavy-section steel specimen belonging to the Pressure Vessel Research Committee program. Using the technique the flaws occurring in the weld area were characterized in quantitative terms of both dimension and orientation. Several modifications of the technique were made during the study to include the application of several transducers and to consider ultrasonic mode conversion. (U.S.)

  14. Synthesis and ultrasonic characterisation of vitreous holmium phosphates

    International Nuclear Information System (INIS)

    Senin Hassan; Sidek Hj, Abdul Aziz; Abdul Halim Shaari

    1996-01-01

    The ultrasonic properties of holmium metaphosphate glasses (Ho sub 2 O sub 3) sub x (P sub 2 O sub 5) sub 1-x, with the mole fraction of x of holmium oxide equal to 0.208, 0.22 and 0.231 respectively, have been determined from measurements of the effects of temperature and hydrostatic pressure on ultrasonic wave velocities. At temperature below about 100K, the ultrasonic wave velocity of this type of rare earth phosphate glasses become anomalously dependent upon temperature; a behaviour associated with the interaction between acoustic phonons and two level systems. The hydrostatic pressure derivatives (∂ C sup S sub IJ / ∂ P) sub p=0 of the elastic stiffnesses C sub IJ and also (∂ C sup S sub IJ / ∂ P) sub p=0 of the bulk modulus B sup S of these glasses are anomalously negative. Both longitudinal γ sub L and shear γ sub S acoustic mode Gruneisen parameters are small and negative : the application of pressure softens the long-wavelength acoustic phonon mode frequencies. The results confirmed that the holmium phosphate glasses show an extraordinary elastic behaviour under high pressures

  15. Contribution of dynamic focusing to ultrasonic defect characterization

    International Nuclear Information System (INIS)

    Mahaut, S.

    1997-01-01

    Non destructive testing of vessels of pressurized water reactors uses ultrasonic focused transducers, with spherically shaped emitting surface or requiring an acoustic lens. But a mechanically focused transducer has to be used for a given inspection zone and for a fixed control configuration. The aim of this thesis is to improve ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of a ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of an ultrasonic transducer split into an array of individually controlled elements, allowing to apply delay and amplitude laws, calculated from modeling or experimentally deduced. Acoustical characteristics of the ultrasonic beam in the inspected specimen this can be electronically controlled; refraction angle, depth focusing, beam width. We briefly describe in the first chapter a theoretical modeling of the ultrasonic field radiated through a fluid/solid interface, extended to phase array transducers. This model is based on the integral formulation of Rayleigh, modified to take into account transmission through a fluid/solid (homogeneous and isotropic), of planar or cylindrical shape. In the second chapter an experimental study of this technique, with delay and amplitude laws given from the model, is presented, showing the efficiency of this method to adjust the acoustic performances. In he third chapter, experimental delay laws, extracted from the time distribution of signals received by the array (issued from a preliminary detected reflector), are used to provide an optimal imaging of the defect. This self-focusing procedure shows to adapt to a defect without using theoretical delays. The last chapter is dedicated to different applications devoted to improved defect characterization. The first application uses amplitude distribution received by the array, pointing out geometric characteristics of the reflector, while the second application

  16. Experimental Study of Shock Generated Compressible Vortex Ring

    Science.gov (United States)

    Das, Debopam; Arakeri, Jaywant H.; Krothapalli, Anjaneyulu

    2000-11-01

    Formation of a compressible vortex ring and generation of sound associated with it is studied experimentally. Impulse of a shock wave is used to generate a vortex ring from the open end of a shock-tube. Vortex ring formation process has been studied in details using particle image Velocimetry (PIV). As the shock wave exits the tube it diffracts and expands. A circular vortex sheet forms at the edge and rolls up into a vortex ring. Far field microphone measurement shows that the acoustic pressure consists of a spike due to shock wave followed by a low frequency pressure wave of decaying nature, superimposed with high frequency pressure wave. Acoustic waves consist of waves due to expansion, waves formed in the tube during diaphragm breakage and waves associated with the vortex ring and shear-layer vortices. Unsteady evolution of the vortex ring and shear-layer vortices in the jet behind the ring is studied by measuring the velocity field using PIV. Corresponding vorticity field, circulation around the vortex core and growth rate of the vortex core is calculated from the measured velocity field. The velocity field in a compressible vortex ring differs from that of an incompressible ring due to the contribution from both shock and vortex ring.

  17. Ultrasonic Fingerprint Sensor With Transmit Beamforming Based on a PMUT Array Bonded to CMOS Circuitry.

    Science.gov (United States)

    Jiang, Xiaoyue; Tang, Hao-Yen; Lu, Yipeng; Ng, Eldwin J; Tsai, Julius M; Boser, Bernhard E; Horsley, David A

    2017-09-01

    In this paper, we present a single-chip 65 ×42 element ultrasonic pulse-echo fingerprint sensor with transmit (TX) beamforming based on piezoelectric micromachined ultrasonic transducers directly bonded to a CMOS readout application-specific integrated circuit (ASIC). The readout ASIC was realized in a standard 180-nm CMOS process with a 24-V high-voltage transistor option. Pulse-echo measurements are performed column-by-column in sequence using either one column or five columns to TX the ultrasonic pulse at 20 MHz. TX beamforming is used to focus the ultrasonic beam at the imaging plane where the finger is located, increasing the ultrasonic pressure and narrowing the 3-dB beamwidth to [Formula: see text], a factor of 6.4 narrower than nonbeamformed measurements. The surface of the sensor is coated with a poly-dimethylsiloxane (PDMS) layer to provide good acoustic impedance matching to skin. Scanning laser Doppler vibrometry of the PDMS surface was used to map the ultrasonic pressure field at the imaging surface, demonstrating the expected increase in pressure, and reduction in beamwidth. Imaging experiments were conducted using both PDMS phantoms and real fingerprints. The average image contrast is increased by a factor of 1.5 when beamforming is used.

  18. Design and Manufacture an Ultrasonic Dispersion System with Automatic Frequency Adjusting Property

    Directory of Open Access Journals (Sweden)

    Herlina ABDUL RAHIM

    2011-03-01

    Full Text Available This paper a novel ultrasonic dispersion system for the cleaning application or dispersing of particles which are mixed in liquid has been proposed. The frequency band of designed system is 30 kHz so that the frequency of ultrasonic wave sweeps from 30 kHz to 60 kHz with 100 Hz steps. One of the superiority of manufactured system in compare with the other similar systems which are available in markets is that this system can transfer the maximum and optimum energy of ultrasonic wave inside the liquid tank with the high efficiency in the whole of the usage time of the system. The used ultrasonic transducers in this system as the generator of ultrasonic wave is the type of air coupled ceramic ultrasonic piezoelectric with the nominal maximum power 50 Watt. The frequency characteristic of applied piezoelectric is that it produces the maximum amplitude of ultrasonic wave on the resonance frequency, so this system is designed to work on resonance frequency of piezoelectric, continuously. This is done by the use of control system which is consisted of two major parts, sensing part and controlling part. The manufactured ultrasonic dispersion system is consisted of 9 piezoelectrics so that it can produce 450 watt ultrasonic energy, totally. The main purpose of this project is to produce a safety system especially for fatigue car driver so as to prevent from accidents. The statistic on road fatality shows that human error constitute of 64.84 % road accidents fatality and 17.4 % due to technical factors. These systems encompassed the approach of hand pressure applied on the steering wheel. The steering will be installed with pressure sensors. At the same time these sensors can be used to measure gripping force while driving.

  19. Photoacoustic imaging of blood vessels with a double-ring sensor featuring a narrow angular aperture

    NARCIS (Netherlands)

    Kolkman, R.G.M.; Hondebrink, Erwin; Steenbergen, Wiendelt; van Leeuwen, Ton; de Mul, F.F.M.

    2004-01-01

    A photoacoustic double-ring sensor, featuring a narrow angular aperture, is developed for laser-induced photoacoustic imaging of blood vessels. An integrated optical fiber enables reflection-mode detection of ultrasonic waves. By using the cross-correlation between the signals detected by the two

  20. Innovative ultrasonics for power plant commissioning

    International Nuclear Information System (INIS)

    Murphy, R.V.; Alikhan, S.

    1983-05-01

    During the commissioning of a nuclear power plant, the usual role of ultrasonics is associated with nondestructive testing of welds. There is, however, a variety of undesirable conditions associated with the fluids carried through the various reactor systems which may be just as important to station operation. A variety of unusual ultrasonic techniques has been developed for testing fluid systems at the Point Lepreau Generating Station. This paper uses the experience gained at the Point Lepreau reactor to illustrate the valuable information which can be gained from these measurements, such as: fluid level in pipes and headers; fluid level in pressure vessels; detection, and sizing of debris in pipes; in situ measurement and verification of orifice condition; detection and location of cavitation, water hammer, valve leakage; quantitative measurement of gate movement within the body of an inservice valve; determination of valve position; detection and imaging of flow separation; detection and location of leaks in concrete containment structures; verification of design flows; balancing of loop flows; and detection of low flow. The application of these techniques at other reactor sites is also discussed

  1. Ultrasonic level, temperature, and density sensor

    International Nuclear Information System (INIS)

    Rogers, S.C.; Miller, G.N.

    1982-01-01

    A sensor has been developed to measure simultaneously the level, temperature, and density of the fluid in which it is immersed. The sensor is a thin, rectangular stainless steel ribbon which acts as a waveguide and is housed in a perforated tube. The waveguide is coupled to a section of magnetostrictive magnetic-coil transducers. These tranducers are excited in an alternating sequence to interrogate the sensor with both torsional ultrasonic waves, utilizing the Wiedemann effect, and extensional ultrasonic waves, using the Joule effect. The measured torsional wave transit time is a function of the density, level, and temperature of the fluid surrounding the waveguide. The measured extensional wave transit time is a function of the temperature of the waveguide only. The sensor is divided into zones by the introduction of reflecting surfaces at measured intervals along its length. Consequently, the transit times from each reflecting surface can be analyzed to yield a temperature profile and a density profile along the length of the sensor. Improvements in acoustic wave dampener and pressure seal designs enhance the compatibility of the probe with high-temperature, high-radiation, water-steam environments and increase the likelihood of survival in such environments. Utilization of a microcomputer to automate data sampling and processing has resulted in improved resolution of the sensor

  2. Ultrasonic measurements and technologies

    CERN Document Server

    Kočiš, Štefan

    1996-01-01

    An impulse for writing this book has originated from the effort to sum­ marize and publicise the acquired results of a research team at the De­ partment of Automation of the Faculty of Electrical Engineering and In­ formatics, Slovak Technical University in Bratislava. The research team has been involved for a long time with control problems for machine production mechanisms and, in recent (approximately 15) years, its effort was aimed mostly at the control of electrical servosystems of robots. Within this scope, the members of the authors' staff solved the State Re­ search Task Ultrasonic sensing of the position of a robot hand, which was coordinated by the Institute of Technical Cybernetics of the Slovak Academy of Sciences in Bratislava. The problem was solved in a complex way, i.e. from a conceptual de­ sign of the measurement, through the measurement and evaluation sys­ tem, up to connection to the control system of a robot. Compensation of the atmospheric influence on the precision of measurement,...

  3. Ultrasonic-testing method

    International Nuclear Information System (INIS)

    Thome, Paul.

    1973-01-01

    Description is given of a device adapted to the detection, by means of ultrasonic waves, of all the flaws and defects included in workpieces when only one face of the latter is accessible. A beam is directed towards the rear-face of the workpiece (e.g. a plate) on which it is reflected. The image thus reflected is fed into a receiver. The latter is under the control of the displacement of that image; simultaneously a transducer checks the condition of the mirror at the places where the beam is reflected. Whenever a flow or defect comes between, a silent zone is formed. By recording the silent zones with respect to the positions of several emitters, it is possible to locates a flaw and to define the outline thereof. The apparatus comprises several ''emitter-receiver'' groups intersecting over the emitter used in order to check the good conditions of the mirror. The invention can be used for searching and identifying flaws and defects in buildings which have to be of top quality (e.g., cofferdams, nuclear devices, shipbuilding yards, aeronautics) [fr

  4. Ultrasonic monitoring system

    International Nuclear Information System (INIS)

    McLain, R.E.

    1975-01-01

    The ultrasonic monitoring system is used in LMFBR's, BWR's or PWR's. A remotely controlled, movable instrument carrier may be used which contains the piezo-electric transducer and is connected to the main control console by a transmission cable. An excitation pulse coming from a pulse generator is used to excite the transducer with a maximum of energy, independent of the length of the transmission line. Pulse width and pulse amplitude can be set without any direct interference into the transducer. For this purpose, a resistor whose impedance has been matched to that of the transmission line is connected to the input of the transmission line. Moreover, a capacitor for generation of the excitation pulse is coupled with the transmission line by means of a four-layer switching diode and is discharged. For termination of the excitation and the control pulses, respectively, another four-layer switching diode connected parallel to the capacitor quickly discharges the capacitor. The capacitor and the capacitance of the line constitute a voltage divider. In this way it is possible to change the length of the transmission line and, to safeguard the generation of a pulse of the desired amplitude, only vary the capacitance of the capacitor. (DG/RF) [de

  5. Token Ring Project

    Directory of Open Access Journals (Sweden)

    Adela Ionescu

    2007-01-01

    Full Text Available Ring topology is a simple configuration used to connect processes that communicate among themselves. A number of network standards such as token ring, token bus, and FDDI are based on the ring connectivity. This article will develop an implementation of a ring of processes that communicate among themselves via pipe links. The processes are nodes in the ring. Each process reads from its standard input and writes in its standard output. N-1 process redirects the its standard output to a standard input of the process through a pipe. When the ring-structure is designed, the project can be extended to simulate networks or to implement algorithms for mutual exclusion

  6. Ultrasonic propulsion of kidney stones.

    Science.gov (United States)

    May, Philip C; Bailey, Michael R; Harper, Jonathan D

    2016-05-01

    Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

  7. An Estimation of Wave Attenuation Factor in Ultrasonic Assisted Gravity Drainage Process

    Directory of Open Access Journals (Sweden)

    Behnam Keshavarzi

    2014-01-01

    Full Text Available It has been proved that ultrasonic energy can considerably increase the amount of oil recovery in an immiscible displacement process. Although many studies have been performed on investigating the roles of ultrasonic waves, based on the best of our knowledge, little attention has been paid to evaluate wave attenuation parameter, which is an important parameter in the determination of the energy delivered to the porous medium. In this study, free fall gravity drainage process is investigated in a glass bead porous medium. Kerosene and Dorud crude oil are used as the wetting phases and air is used as the non-wetting phase. A piston-like displacement model with considering constant capillary pressure and applying Corey type approximation for relative permeabilities of both wetting and nonwetting phases is applied. A pressure term is considered to describe the presence of ultrasonic waves and the attenuation factor of ultrasonic waves is calculated by evaluating the value of external pressure applied to enhance the flow using the history matching of the data in the presence and absence of ultrasonic waves. The results introduce the attenuation factor as an important parameter in the process of ultrasonic assisted gravity drainage. The results show that only a low percentage of the ultrasonic energy (5.8% for Dorud crude oil and 3.3% for kerosene is delivered to the flow of the fluid; however, a high increase in oil recovery enhancement (15% for Dorud crude oil and 12% for Kerosene is observed in the experiments. This proves that the ultrasonic waves, even when the contribution is not substantial, can be a significantly efficient method for flow enhancement.

  8. Mechanisms of microstructure formation under the influence of ultrasonic vibrations

    Science.gov (United States)

    Rakita, Milan

    Positive effects of ultrasound on crystallization have been known for almost 90 years. Application of ultrasound has been very successful in many industries, most notably in chemistry, creating a new branch of science - sonochemistry. However, ultrasonication has not found wide commercial application in the solidification processing. The reason for that is the complexity of underlying phenomena and the lack of predicting models which correlate processing parameters with the properties of a product. The purpose of this study is to give some contribution toward better understanding of mechanisms that lead to changes in the solidifying microstructure. It has been found that, under experimental conditions used in this work, cavitation-induced nucleation is the major contributor to the grain refinement. Ultrasonication at minimal supercoolings is expected to give maximal grain refinement. Dendrite fragmentation has not shown to be a significant contributor to the grain refinement. Dendrite fragmentation is maximal if done by bubbles that come in contact with the solidifying phase, or that are created there. Alloys/solutions with long solidification interval, or wide mushy zone, are expected to exhibit more dendrite fragmentation. Bubbles are recognized as a crucial feature in ultrasonication. Their size distribution in the liquid phase prior to ultrasonication dictates the cavitation threshold and intensity of cavitation. For the first time, radiation pressure has been recognized as potentially significant factor in grain refinement. In the experimental setup used in this study, acoustic pressure at the main (driving) frequency is not substantial to cause significant fragmentation, and only dendrites close to the sonotrode were fragmented. However, application of ultrasound with frequencies that are several times higher than the current industrial practice could substantially increase dendrite fragmentation. Appearance of fractional harmonics has also been recognized

  9. Token ring technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This report provides an overview of the IBM Token-Ring technology and products built by IBM and compatible vendors. It consists of two sections: 1. A summary of the design trade-offs for the IBM Token-Ring. 2. A summary of the products of the major token-ring compatible vendors broken down by adapters and components, wiring systems, testing, and new chip technology.

  10. Radioactive gold ring dermatitis

    International Nuclear Information System (INIS)

    Miller, R.A.; Aldrich, J.E.

    1990-01-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy

  11. Ultrasonic stir welding process and apparatus

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2009-01-01

    An ultrasonic stir welding device provides a method and apparatus for elevating the temperature of a work piece utilizing at least one ultrasonic heater. Instead of relying on a rotating shoulder to provide heat to a workpiece an ultrasonic heater is utilized to provide ultrasonic energy to the workpiece. A rotating pin driven by a motor assembly performs the weld on the workpiece. A handheld version can be constructed as well as a fixedly mounted embodiment.

  12. The effects of ultrasonic solidification on aluminum

    OpenAIRE

    Đorđević Slavko 1

    2003-01-01

    The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

  13. The effects of ultrasonic solidification on aluminum

    Directory of Open Access Journals (Sweden)

    Đorđević Slavko 1

    2003-01-01

    Full Text Available The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

  14. Helium-flow measurement using ultrasonic technique

    International Nuclear Information System (INIS)

    Sondericker, J.H.

    1983-01-01

    While designing cryogenic instrumentation for the Colliding Beam Accelerator (CBA) helium-distribution system it became clear that accurate measurement of mass flow of helium which varied in temperature from room to sub-cooled conditions would be difficult. Conventional venturi flow meters full scale differential pressure signal would decrease by more than an order of magnitude during cooldown causing unacceptable error at operating temperature. At sub-cooled temperatures, helium would be pumped around cooling loops by an efficient, low head pressure circulating compressor. Additional pressure drop meant more pump work was necessary to compress the fluid resulting in a higher outlet temperature. The ideal mass flowmeter for this application was one which did not add pressure drop to the system, functioned over the entire temperature range, has high resolution and delivers accurate mass flow measurement data. Ultrasonic flow measurement techniques used successfully by the process industry, seemed to meet all the necessary requirements. An extensive search for a supplier of such a device found that none of the commercial stock flowmeters were adaptable to cryogenic service so the development of the instrument was undertaken by the CBA Cryogenic Control and Instrumentation Engineering Group at BNL

  15. Physics of quantum rings

    International Nuclear Information System (INIS)

    Fomin, Vladimir M.

    2014-01-01

    Presents the new class of materials of quantum rings. Provides an elemental basis for low-cost high-performance devices promising for electronics, optoelectronics, spintronics and quantum information processing. Explains the physical properties of quantum rings to cover a gap in scientific literature. Presents the application of most advanced nanoengineering and nanocharacterization techniques. This book deals with a new class of materials, quantum rings. Innovative recent advances in experimental and theoretical physics of quantum rings are based on the most advanced state-of-the-art fabrication and characterization techniques as well as theoretical methods. The experimental efforts allow to obtain a new class of semiconductor quantum rings formed by capping self-organized quantum dots grown by molecular beam epitaxy. Novel optical and magnetic properties of quantum rings are associated with non-trivial topologies at the nanoscale. An adequate characterization of quantum rings is possible on the basis of modern characterization methods of nanostructures, such as Scanning Tunneling Microscopy. A high level of complexity is demonstrated to be needed for a dedicated theoretical model to adequately represent the specific features of quantum rings. The findings presented in this book contribute to develop low-cost high-performance electronic, spintronic, optoelectronic and information processing devices based on quantum rings.

  16. Commissioning of the diamond light source storage ring vacuum system

    International Nuclear Information System (INIS)

    Cox, M P; Boussier, B; Bryan, S; Macdonald, B F; Shiers, H S

    2008-01-01

    The Diamond storage ring has been operating with a 3 GeV electron beam since September 2006 and 190 A.h of beam dose have been accumulated. The pressure in the storage ring is 4.2 10 -10 mbar without beam, rising to 7.9 10 -10 mbar with 125 mA of stored beam. Data on the storage ring vacuum performance and experience from commissioning and beam conditioning are presented

  17. 21 CFR 872.4850 - Ultrasonic scaler.

    Science.gov (United States)

    2010-04-01

    ... DEVICES DENTAL DEVICES Surgical Devices § 872.4850 Ultrasonic scaler. (a) Identification. An ultrasonic scaler is a device intended for use during dental cleaning and periodontal (gum) therapy to remove calculus deposits from teeth by application of an ultrasonic vibrating scaler tip to the teeth. (b...

  18. Pitch-catch only ultrasonic fluid densitometer

    Science.gov (United States)

    Greenwood, M.S.; Harris, R.V.

    1999-03-23

    The present invention is an ultrasonic fluid densitometer that uses a material wedge and pitch-catch only ultrasonic transducers for transmitting and receiving ultrasonic signals internally reflected within the material wedge. Density of a fluid is determined by immersing the wedge into the fluid and measuring reflection of ultrasound at the wedge-fluid interface. 6 figs.

  19. Development of a finite element model for ultrasonic NDT phenomena

    International Nuclear Information System (INIS)

    Lord, W.

    1988-01-01

    Ultrasonic NDT techniques are used extensively in the nuclear industry for the detection and characterization of defects in critical structural components such as pressure vessels and piping. The feasibility of applying finite element analysis methods to the problem of modeling ultrasound/defect interactions has been shown. Considerable work remains to be done before a full three-dimensional model is available for the prediction of realistic ultrasonic transducer signals from sound wave interaction with arbitrarily shaped defects in highly attenuative and anisotropic materials. However, a two-dimensional code has been developed that is capable of predicting finite aperture ultrasonic transducer signals associated with wave propagations in isotropic materials and that shows good qualitative agreement with corresponding experimental observations. This 2-D code has now been extended to include anisotropic materials such as centrifugally cast stainless steel (CCSS), a necessary step in the development of the full 3-D code. Results are given showing the capability of the 2-D code to predict the anomalous wave behavior normally associated with ultrasonic wave propagation in anisotropic materials. In addition, a new signal processing technique is discussed, based on the Wigner transformation, that shows promise for application to centrifugally cast stainless steel NDT problems

  20. An N-body Integrator for Planetary Rings

    Science.gov (United States)

    Hahn, Joseph M.

    2011-04-01

    A planetary ring that is disturbed by a satellite's resonant perturbation can respond in an organized way. When the resonance lies in the ring's interior, the ring responds via an m-armed spiral wave, while a ring whose edge is confined by the resonance exhibits an m-lobed scalloping along the ring-edge. The amplitude of these disturbances are sensitive to ring surface density and viscosity, so modelling these phenomena can provide estimates of the ring's properties. However a brute force attempt to simulate a ring's full azimuthal extent with an N-body code will likely fail because of the large number of particles needed to resolve the ring's behavior. Another impediment is the gravitational stirring that occurs among the simulated particles, which can wash out the ring's organized response. However it is possible to adapt an N-body integrator so that it can simulate a ring's collective response to resonant perturbations. The code developed here uses a few thousand massless particles to trace streamlines within the ring. Particles are close in a radial sense to these streamlines, which allows streamlines to be treated as straight wires of constant linear density. Consequently, gravity due to these streamline is a simple function of the particle's radial distance to all streamlines. And because particles are responding to smooth gravitating streamlines, rather than discrete particles, this method eliminates the stirring that ordinarily occurs in brute force N-body calculations. Note also that ring surface density is now a simple function of streamline separations, so effects due to ring pressure and viscosity are easily accounted for, too. A poster will describe this N-body method in greater detail. Simulations of spiral density waves and scalloped ring-edges are executed in typically ten minutes on a desktop PC, and results for Saturn's A and B rings will be presented at conference time.

  1. Ultrasonic techniques for fluids characterization

    CERN Document Server

    Povey, Malcolm J W

    1997-01-01

    This book is a comprehensive and practical guide to the use of ultrasonic techniques for the characterization of fluids. Focusing on ultrasonic velocimetry, the author covers the basic topics and techniques necessaryfor successful ultrasound measurements on emulsions, dispersions, multiphase media, and viscoelastic/viscoplastic materials. Advanced techniques such as scattering, particle sizing, and automation are also presented. As a handbook for industrial and scientific use, Ultrasonic Techniques for Fluids Characterization is an indispensable guide to chemists and chemical engineers using ultrasound for research or process monitoring in the chemical, food processing, pharmaceutical, cosmetic, biotechnology,and fuels industries. Key Features * Appeals to anyone using ultrasound to study fluids * Provides the first detailed description of the ultrasound profiling technique for dispersions * Describes new techniques for measuring phase transitions and nucleation, such as water/ice and oil/fat * Presents the l...

  2. Ultrasonic inspection development at HEDL

    International Nuclear Information System (INIS)

    Day, C.K.; Mech, S.J.; Michaels, T.E.; Dixon, N.E.

    1978-01-01

    Ultrasonic testing methods and equipment are being developed to support preservice and in-service inspection of selected FFTF welds. A digital computer system is employed in the analysis of both simulated FFTF pipe sections and plate specimens containing fatigue cracks. It is anticipated that test evaluation standards containing fatigue cracks will partially eliminate questions formerly associated with weld test calibration producers by providing natural cracks which follow grain boundaries and stress patterns resembling piping situ conditions. Studies have revealed that commercial transducers may satisfy LMFBR ultrasonic pipe inspection applications: The test system evaluation included transducers and wedge coupling and fluid coupling materials which exhibited acceptable performance at temperatures to 2300C. Results are presented that demonstrate the feasibility of ultrasonic inspection of components immersed in sodium at temperatures to 2600C. (UK)

  3. Ultrasonic wave propagation in powders

    Science.gov (United States)

    Al-Lashi, R. S.; Povey, M. J. W.; Watson, N. J.

    2018-05-01

    Powder clumps (cakes) has a significant effect on the flowability and stability of powders. Powder caking is mainly caused by moisture migration due to wetting and environmental (temperature and humidity) changes. The process of moisture migration caking involves creating liquid bridges between the particles during condensation which subsequently harden to form solid bridges. Therefore, an effective and reliable technique is required to quantitatively and non-invasively monitor caking kinetics and effective stiffness. This paper describes two ultrasonic instruments (ultrasonic velocity pulse and airborne ultrasound systems) that have been used to monitor the caking phenomenon. Also, it discusses the relationship between the ultrasonic velocity and attenuation measurements and tracking caking kinetics and the effective stiffness of powders.

  4. Vortex rings from Sphagnum moss capsules

    Science.gov (United States)

    Whitaker, Dwight; Strassman, Sam; Cha, Jung; Chang, Emily; Guo, Xinyi; Edwards, Joan

    2010-11-01

    The capsules of Sphagnum moss use vortex rings to disperse spores to suitable habitats many kilometers away. Vortex rings are created by the sudden release of pressurized air when the capsule ruptures, and are an efficient way to carry the small spores with low terminal velocities to heights where they can be carried by turbulent wind currents. We will present our computational model of these explosions, which are carried out using a 2-D large eddy simulation (LES) on FLUENT. Our simulations can reproduce the observed motion of the spore clouds observed from moss capsules with high-speed videos, and we will discuss the roles of bursting pressure, cap mass, and capsule morphology on the formation and quality of vortex rings created by this plant.

  5. Ultrasonic sweep arm for sodium cooled reactors

    International Nuclear Information System (INIS)

    Rohrbacher, H.A.; Bartholomay, R.

    1975-05-01

    This report describes experience in the use of a new type of monitoring and testing device to be applied in conjunction with components under sodium. In the method outlined, ultrasonic pulses are used which are emitted into the sodium plenum of fast breeder reactors by newly developed high temperature transducers. The basic work was conducted under out-of-pile conditions in a sodium tank of the sodium tank facility of the Karlsruhe Institute for Reactor Development. The sensor development, which preceded this phase, resulted in the use of soldered lithium niobate crystals whose operating characteristics were improved by the preliminary treatment outlined in the report. Special materials and techniques suitable for sensor fabrication are proposed. An alternative to soldering is suggested for contacting the crystals with their diaphragms, i.e. a contact pressure concept for the range of application up to 2 MHz. (orig.) [de

  6. Inline Ultrasonic Rheometry by Pulsed Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Pfund, David M.; Greenwood, Margaret S.; Bamberger, Judith A.; Pappas, Richard A.

    2006-12-22

    This will be a discussion of the non-invasive determination of the viscosity of a non-Newtonian fluid in laminar pipe flow over the range of shear rates present in the pipe. The procedure used requires knowledge of the flow profile in and the pressure drop along a long straight run of pipe. The profile is determined by using a pulsed ultrasonic Doppler velocimeter. This approach is ideal for making non-invasive, real-time measurements for monitoring and control. Rheograms of a shear thinning, thixotropic gel will be presented. The operating parameters and limitations of the Doppler-based instrument will be discussed. The most significant limitation is velocity gradient broadening of the Doppler spectra near the walls of the pipe. This limitation can be significant for strongly shear thinning fluids (depending also on the ratio of beam to pipe diameter and the transducer's insertion angle).

  7. Ultrasonic wave damage detecting device

    International Nuclear Information System (INIS)

    Miura, Yuichi; Nagao, Tetsuya; Nishi, Yuji; Kubota, Keisuke; Maruyama, Takayuki.

    1994-01-01

    Upon detecting a damage for a joint between a connecting nozzle at the outer circumference of a reactor pressure vessel and pipelines, the present invention greatly shortens the operation time. That is, it is noted that the connecting nozzle has a tapered portion and a small-diameter portion in view of strength. A main magnetic wheel supported on a base of a running vehicle is attracted to the small-diameter portion and an auxiliary magnet wheel is attracted to the tapered portion respectively and they are rolled. This regulate the deviation of the position of the base of the running vehicle in axial direction of the nozzle by the small-diameter portion and the tapered portion. Accordingly, the running vehicle can be circulated along a predetermined course on the outer circumference of the connecting nozzle without using tracks such as an existent ring track. The test can be performed conveniently only by placing the damage detecting device on the connecting nozzle. As a result, preparation time required before the test can remarkably be shortened. (I.S.)

  8. On line ultrasonic integrated backscatter

    International Nuclear Information System (INIS)

    Landini, L.; Picano, E.; Mazzarisi, A.; Santarelli, F.; Benassi, A.; De Pieri, G.

    1988-01-01

    A new equipment for on-line evaluation of index based on two-dimensional integrated backscatter from ultrasonic images is described. The new equipment is fully integrated into a B-mode ultrasonic apparatus which provides a simultaneous display of conventional information together with parameters of tissue characterization. The system has been tested with a backscattering model of microbubbles in polysaccharide solution, characterized by a physiological exponential time decay. An exponential fitting to the experimental data was performed which yielded r=0.95

  9. Ultrasonically assisted drilling of rocks

    Science.gov (United States)

    Mikhailova, N. V.; Onawumi, P. Y.; Roy, A.; Silberschmidt, V. V.

    2018-05-01

    Conventional drilling of rocks can generate significant damage in the drilled material; a material layer is often split off a back surface of a sample during drilling, negatively affecting its strength. To improve finish quality, ultrasonically assisted drilling (UAD) was employed in two rocks - sandstone and marble. Damage areas in both materials were reduced in UAD when compared to conventional drilling. Reductions in a thrust force and a torque reduction were observed only for UAD in marble; ultrasonic assistance in sandstone drilling did not result in improvements in this regard.

  10. Very high temperature ultrasonic thermometer

    International Nuclear Information System (INIS)

    Jorzik, E.

    1983-01-01

    An ultrasonic thermometer comprises an electric pulse transducer head, a pulse transmission line, a notched sensor wire attached to and extending along the axis of said transmission line and a sheath enclosing the transmission line and the sensor wire, a portion of the interior face of the sheath being covered by a stuffing material along at least the length of the notched part of the sensor wire, such that contact between the sensor wire and the stuffing material does not substantially give rise to reflection of an ultrasonic pulse at the point of contact. (author)

  11. Comparing weld inspection codes: radiography vs. ultrasonics

    International Nuclear Information System (INIS)

    Moles, M.; Ginzel, E.

    2007-01-01

    Requirements for weld quality are continually increasing. This is due to a combination of factors: increased public awareness; bigger legal penalties; improved and thinner steels; better analysis techniques such as Engineering Critical Assessment (ECA); higher material costs. Weld quality is primarily dictated by construction codes, which should reflect the needs of society and industry: safety, the environment, society, and cost-effectiveness. As R and D produces new products, techniques and procedures, ideally these developments should be reflected in the codes. While pressure vessel and structural welding are certainly included here, it is really pipeline weld inspections that are setting the pace on new developments. For pipelines, a major shift was made from radiography to ultrasonics in Alberta some decades ago. This was driven by the 'need for speed', plus the requirement to size defects in the vertical plane for ECA (also called Fracture Mechanics or Fitness-For-Purpose). One of the main objectives of ECA was to benefit from the calculated fracture toughness of materials, and not to rely on the overly conservative workmanship criteria in radiography. In practice, performing repairs on higher quality material often does more harm than good; changing the microstructure can seriously compromise the material properties. Rising steel costs are another major driving force, so higher strength, thinner materials are being used. Under these conditions, ECA and defect sizing are critical. This paper compares where the various North American codes for pipelines, pressure vessels and structural welds stand on using advanced inspection techniques: ultrasonics, phased arrays, ECA, sizing techniques. For those codes which are not using the latest technologies, there are typical routes for incorporating them. (author)

  12. Smart ultrasonic flowmeter used for the operation support of water resource management in the agricultural areas

    Science.gov (United States)

    Elmostafa, Ziani; Mustapha, Bennouna; Boissier, Raymond

    2008-10-01

    Ultrasonic sensors transmit acoustic waves and receive them later. This is done by ultrasonic transducers, which transform an ultrasonic wave into an electrical signal and vice versa. Often, it is possible to use the same transducer for both transmitting and receiving. The most important parts of any ultrasonic sensor are the transducers. The spectral and spatial radiation characteristics of these components are the prime determinants of sensor performance. Such transducers must have a robust design, stable radiation pattern (high directivity) and good receiving sensitivity. Intelligent ultrasonic sensors have the possibility to extract the information about the variables to be measured, carried by the ultrasonic signals efficiently and with accuracy. To achieve this performance, the signals are processed by dedicated hardware (accurate electronic measuring devices). Ultrasound has the property, that its velocity is strongly affected by the flow velocity of the fluids in which it propagates. The ultrasonic flowmeters have gained a lot of attention over the past few years; they have several advantages over the differential pressure flowmeter, turbine meters, coriolis meters and vortex meters. They are widely used to measure the flow of liquids, first, they are either less intrusive (wetted flowmeter) or non-intrusive (clamp-on flowmeter), depending on the model. Also, they don't have moving parts that are subject to wear over time, and with minimum obstruction of the flow. Ultrasonic flowmeter are not limited to clean liquids (Transit time flowmeter), a special type of ultrasonic flowmeter can also accurately measure the flow of slurries and liquids with many impurities (Doppler flowmeter). This part of paper describes the intelligent ultrasonic sensor. The conception or the realization of intelligent ultrasonic sensor requires the synthesis of several technologies, a knowledge in the fields of sensor, digital ultrasonic signal processing, distributed system and

  13. Spatially resolved ultrasonic attenuation in resistance spot welds: implications for nondestructive testing.

    Science.gov (United States)

    Mozurkewich, George; Ghaffari, Bita; Potter, Timothy J

    2008-09-01

    Spatial variation of ultrasonic attenuation and velocity has been measured in plane parallel specimens extracted from resistance spot welds. In a strong weld, attenuation is larger in the nugget than in the parent material, and the region of increased attenuation is surrounded by a ring of decreased attenuation. In the center of a stick weld, attenuation is even larger than in a strong weld, and the low-attenuation ring is absent. These spatial variations are interpreted in terms of differences in grain size and martensite formation. Measured frequency dependences indicate the presence of an additional attenuation mechanism besides grain scattering. The observed attenuations do not vary as commonly presumed with weld quality, suggesting that the common practice of using ultrasonic attenuation to indicate weld quality is not a reliable methodology.

  14. Piezoelectric Sensor to Measure Soft and Hard Stiffness with High Sensitivity for Ultrasonic Transducers

    Directory of Open Access Journals (Sweden)

    Yan-Rui Li

    2015-06-01

    Full Text Available During dental sinus lift surgery, it is important to monitor the thickness of the remaining maxilla to avoid perforating the sinus membrane. Therefore, a sensor should be integrated into ultrasonic dental tools to prevent undesirable damage. This paper presents a piezoelectric (PZT sensor installed in an ultrasonic transducer to measure the stiffness of high and low materials. Four design types using three PZT ring materials and a split PZT for actuator and sensor ring materials were studied. Three sensor locations were also examined. The voltage signals of the sensor and the displacement of the actuator were analyzed to distinguish the low and high stiffness. Using sensor type T1 made of the PZT-1 material and the front location A1 provided a high sensitivity of 2.47 Vm/kN. The experimental results demonstrated that our design can measure soft and hard stiffness.

  15. EBT ring physics

    International Nuclear Information System (INIS)

    Uckan, N.A.

    1980-04-01

    This workshop attempted to evaluate the status of the current experimental and theoretical understanding of hot electron ring properties. The dominant physical processes that influence ring formation, scaling, and their optimal behavior are also studied. Separate abstracts were prepared for each of the 27 included papers

  16. Degradation evaluation of high temperature pipeline material for power plant using ultrasonic noise analysis

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Chung, Min Hwa; Cho, Yong Sang; Lee, In Cheol

    2001-01-01

    Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep and thermal fatigue damage due to severe operating conditions such as high temperature and high pressure for an extended period time. Conventional measurement techniques for measuring creep damage have such disadvantages as complex preparation and measurement procedures, too many control parameters. And also these techniques have low practicality and applied only to component surfaces with good accessibility. In this paper, artificial degradation test and ultrasonic measurement for their degraded specimens were carried out for the purpose of evaluation for creep and thermal fatigue damage. Absolute measuring method of quantitative ultrasonic measurement for material degradation was established, and long term creep/thermal fatigue degradation tests using life prediction formula were carried out. As a result of ultrasonic tests for crept and thermal fatigued specimens, we conformed that the ultrasonic noise linearly increased in proportion to the increase of degradation.

  17. Ultrasonic detection technology based on joint robot on composite component with complex surface

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Juan; Xu, Chunguang; Zhang, Lan [School of Mechanical Engineering, Beijing Institute of Technology, Beijing (China)

    2014-02-18

    Some components have complex surface, such as the airplane wing and the shell of a pressure vessel etc. The quality of these components determines the reliability and safety of related equipment. Ultrasonic nondestructive detection is one of the main methods used for testing material defects at present. In order to improve the testing precision, the acoustic axis of the ultrasonic transducer should be consistent with the normal direction of the measured points. When we use joint robots, automatic ultrasonic scan along the component surface normal direction can be realized by motion trajectory planning and coordinate transformation etc. In order to express the defects accurately and truly, the robot position and the signal of the ultrasonic transducer should be synchronized.

  18. Annular spherically focused ring transducers for improved single-beam acoustical tweezers

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F. G., E-mail: F.G.Mitri@ieee.org [Chevron, Area 52 Technology—ETC, Santa Fe, New Mexico 87508 (United States)

    2016-02-14

    The use of ultrasonic transducers with a central hollow is suggested for improved single-beam acoustical tweezers applications. Within the framework of the Fresnel-Kirchhoff parabolic approximation, a closed-form partial-wave series expansion (PWSE) for the incident velocity potential (or pressure) field is derived for an annular spherically focused ring (asfr) with uniform vibration across its surface in spherical coordinates. The Rayleigh-Sommerfeld diffraction integral and the addition theorems for the Legendre and spherical wave functions are used to obtain the PWSE assuming a weakly focused beam (with a focusing angle α ≤ 20°). The PWSE allows evaluating the incident field from the finite asfr in 3D. Moreover, the obtained solution allows computing efficiently the acoustic scattering and radiation force on a sphere centered on the beam's axis of wave propagation. The analytical solution is valid for wavelengths largely exceeding the radius of the asfr and when the viscosity of the surrounding fluid can be neglected. Numerical predictions for the beam-forming, scattering, and axial time-averaged radiation force are performed with particular emphasis on the asfr thickness, the axial distance separating the sphere from the center of the transducer, the (non-dimensional) size of the transducer, as well as the sphere's elastic properties without restriction to the long- (i.e., Rayleigh) or the short-wavelength (i.e., ray acoustics) regimes. Potential applications of the present solution are in beam-forming design, particle tweezing, and manipulation due to negative forces using ultrasonic asfr transducers.

  19. Measurement of a 3D Ultrasonic Wavefield Using Pulsed Laser Holographic Microscopy for Ultrasonic Nondestructive Evaluation

    Directory of Open Access Journals (Sweden)

    Xing Wang

    2018-02-01

    Full Text Available In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pulsed laser, ultrasonic excitation, and synchronization and control circuit is designed. A consecutive sequence of holograms of ultrasonic wavefields are recorded by the system. The interferograms are calculated from the recorded holograms at different time sequence. The amplitudes and phases of the transient ultrasonic wavefields are recovered from the interferograms by phase unwrapping. The consecutive sequence of transient ultrasonic wavefields are stacked together to generate 3D ultrasonic wavefields. Simulation and experiments are carried out to verify the proposed technique, and preliminary results are presented.

  20. Evolution of the ring current during two geomagnetic storms

    International Nuclear Information System (INIS)

    Lui, A.T.Y.; McEntire, R.W.; Krimigis, S.M.

    1987-01-01

    The progressive developments in the radial profiles of the particle pressure, plasma beta, and electric currents of the storm time ring current are investigated with data from the medium energy particle analyzer on the AMPTE Charged Particle Explorer spacecraft. Measurements of ions from 25 keV to 1 MeV, which carry 70--85% of the energy density of the entire ring current population, are used in this work. Two geomagnetic storms in September of 1984 are selected and four traversals of the equatorial ring current region during the course of each storm are studied. It is shown that enhancements in the particle pressure occur initially in the outer region and reach the inner region in the late phase of the storm. Structures suggestive of multiple particle injections are seen in the pressure profile. The leading and trailing edges of the particle injection structures are associated, respectively, with the depressions and enhancements of the westward current densities of the ring current. Plasma beta occasionally increases to values of the order of 1 in some regions of the ring current from prestorm values of the order of 0.1 or less. It is also found that the location of the maximum ring current particle pressure can be several earth radii from where the most intense westward ring current flows. This is a consequence of the dominance of pressure gradient current over the current associated with the magnetic field line curvature and particle anisotropy. copyright American Geophysical Union 1987

  1. Microfluidic ultrasonic particle separators with engineered node locations and geometries

    Science.gov (United States)

    Rose, Klint A.; Fisher, Karl A.; Wajda, Douglas A.; Mariella, Jr., Raymond P.; Bailey, Christopher; Dehlinger, Dietrich; Shusteff, Maxim; Jung, Byoungsok; Ness, Kevin D.

    2016-04-26

    An ultrasonic microfluidic system includes a separation channel for conveying a sample fluid containing small particles and large particles, flowing substantially parallel, adjacent to a recovery fluid, with which it is in contact. An acoustic transducer produces an ultrasound standing wave, that generates a pressure field having at least one node of minimum pressure amplitude. An acoustic extension structure is located proximate to said separation channel for positioning said acoustic node off center in said acoustic area and concentrating the large particles in said recovery fluid stream.

  2. Microalgal cell disruption via ultrasonic nozzle spraying.

    Science.gov (United States)

    Wang, M; Yuan, W

    2015-01-01

    The objective of this study was to understand the effect of operating parameters, including ultrasound amplitude, spraying pressure, nozzle orifice diameter, and initial cell concentration on microalgal cell disruption and lipid extraction in an ultrasonic nozzle spraying system (UNSS). Two algal species including Scenedesmus dimorphus and Nannochloropsis oculata were evaluated. Experimental results demonstrated that the UNSS was effective in the disruption of microalgal cells indicated by significant changes in cell concentration and Nile red-stained lipid fluorescence density between all treatments and the control. It was found that increasing ultrasound amplitude generally enhanced cell disruption and lipid recovery although excessive input energy was not necessary for best results. The effect of spraying pressure and nozzle orifice diameter on cell disruption and lipid recovery was believed to be dependent on the competition between ultrasound-induced cavitation and spraying-generated shear forces. Optimal cell disruption was not always achieved at the highest spraying pressure or biggest nozzle orifice diameter; instead, they appeared at moderate levels depending on the algal strain and specific settings. Increasing initial algal cell concentration significantly reduced cell disruption efficiency. In all UNSS treatments, the effectiveness of cell disruption and lipid recovery was found to be dependent on the algal species treated.

  3. Mode structure in an optically pumped D2O far infrared ring laser

    International Nuclear Information System (INIS)

    Yuan, D.C.; Soumagne, G.; Siegrist, M.R.

    1989-07-01

    The mode structures in an optically pumped D 2 O far infrared ring laser and a corresponding linear resonator have been compared. While single mode operation can be obtained over the whole useful pressure range in the ring structure, this is only possible at pressures greater than 8 Torr in the linear resonator case. A numerical model predicts quite well the pulse shape, pressure dependence and influence of the resonator quality in the ring cavity. (author) 12 figs., 8 refs

  4. Ultrasonic inspection of austenitic welds

    International Nuclear Information System (INIS)

    Baikie, B.L.; Wagg, A.R.; Whittle, M.J.; Yapp, D.

    1976-01-01

    Optical and X-ray metallography combined with ultrasonic testing by compression waves was used for inspection of stainless steel weld metal produced by three different welding techniques. X-ray diffraction showed that each weld possessed a characteristic fibre textured structure which was shown by optical microscopy to be parallel to columnar grain boundaries. Metallographic evidence suggested that the development of fibre texture is due to the mechanism of competitive growth. From observations made as a result of optical metallographic examination the orientation of the fibre axis could be predicted if the weld geometry and welding procedure were known. Ultrasonic velocity and attenuation measurements as a continuous function of grain orientation, made on cylinders machined from weld samples, showed that attenuation was strongly orientation dependent. It was concluded that the sensitivity of ultrasonic inspection to small defects is unlikely to be as high for austenitic welds as for ferritic even when transmission is improved by modifying the welding procedure to improve the ultrasonic transmission. (U.K.)

  5. Atmospheric contamination during ultrasonic scaling

    NARCIS (Netherlands)

    Timmerman, MF; Menso, L; Steinfort, J; van Winkelhoff, AJ; van der Weijden, GA

    Objective: The aim of this study was to determine the microbial atmospheric contamination during initial periodontal treatment using a piezoelectric ultrasonic scaler in combination with either high-volume evacuation (HVE) or conventional dental suction (CDS). Methods: The study included 17

  6. Automated evaluation of ultrasonic indications

    International Nuclear Information System (INIS)

    Hansch, M.K.T.; Stegemann, D.

    1994-01-01

    Future requirements of reliability and reproducibility in quality assurance demand computer evaluation of defect indications. The ultrasonic method with its large field of applications and a high potential for automation provides all preconditions for fully automated inspection. The survey proposes several desirable hardware improvements, data acquisition requirements and software configurations. (orig.) [de

  7. Ultrasonic flowmeters. Progress report II

    International Nuclear Information System (INIS)

    Wittekind, W.D.

    1980-01-01

    This progress report presents results of in-plant testing of the prototype ultrasonic flowmeter and describes modifications to the prototype as a result of these tests. The modified prototype, designated MOD-I, is described in detail including the principle of operation, equipment used and the results of both laboratory and in-plant demonstrations

  8. Calculations for Piezoelectric Ultrasonic Transducers

    DEFF Research Database (Denmark)

    Jensen, Henrik

    1986-01-01

    Analysis of piezoelectric ultrasonic transducers implies a solution of a boundary value problem, for a boay which consists of different materials, including a piezoelectric part. The problem is dynamic at frequencies, where a typical wavelength is somewhat less than the size of the body. Radiation...

  9. Nondestructive characterization of metal-matrix-composites by ultrasonic technique

    International Nuclear Information System (INIS)

    Lee, Joon Hyun

    1992-01-01

    Nondestructive characterizations using ultrasonic technique were conducted systematically on Al 2 O 3 short fiber reinforced pure Al and AC8A aluminium metal-matrix composites. In order to determine the elastic moduli of metal-matrix composites(MMCs), Al 2 O 3 /AC8A composites with volume fraction of Al 2 O 3 short fiber varying up to 30% were fabricated by squeeze casting technique. Pure Al and AC8A reinforced with Al 2 O 3 short fiber were also fabricated by changing the fabrication parameters such as the applied pressure, the volume fraction of fiber. The Influences of texture change associated with change of fabrication parameters were investigated using the sophisticated LFB acoustic microscope with the frequency of 225 MHz. Ultrasonic velocities of longitudinal, shear and Rayleigh waves of the composites were measured by pulse-echo method and line-focus-beam(LBF) acoustic microscope. Ultrasonic velocities of the longitudinal, the shear and Rayleigh waves were found to correlate primarily with the volume fraction of Al 2 O 3 . The elastic constants of composites including Young's Modulus, Shear Modulus, Bulk Modulus and Poisson's ratio were determined on the basis of the longitudinal and the shear wave velocities measured by an ultrasonic pulse-echo method. The Young's Modulus of the composites obtained by ultrasonic technique were slightly lower than those measured by 4-point-bend test and also showed relatively good agreements with the calculated results derived from the equal stress condition. The applicability of LFB acoustic microscope on material characterization of the MMCs was discussed on the basis of the relationships between Rayleigh wave velocity as a function of rotated angle of specimen and fabrication parameters of the MMCs.

  10. Ultrasonic C-scan Technique for Nondestructive Evaluation of Spot Weld Quality

    International Nuclear Information System (INIS)

    Park, Ik Gun

    1994-01-01

    This paper discusses the feasibility of ultrasonic C-scan technique for nondestructive evaluation of spot weld quality. Ultrasonic evaluation for spot weld quality was performed by immersion method with the mechanical and the electronic scanning of point-focussed ultrasonic beam(25 MHz). For the sake of the approach to the quantitative measurement of nugget diameter and the discrimination of the corona bond from nugget, preliminary infinitesimal gap experiment by newton ring is tried in order to set up the optimum ultrasonic test condition. Ultrasonic image data obtained were confirmed and compared by optical microscope and SAM(Scanning Acoustic Microscope) observation of the spot-weld cross section. The results show that the nugget diameter can be measured with the accuracy of 1.0mm, and voids included in nugget can be detected to 10μm extent with simplicity and accuracy. Finally, it was found that it is necessary to make a profound study of definite discrimination of corona bond from nugget and the approach of quantitative evaluation of nugget diameter by utilizing the various image processing techniques

  11. On the Laurent polynomial rings

    International Nuclear Information System (INIS)

    Stefanescu, D.

    1985-02-01

    We describe some properties of the Laurent polynomial rings in a finite number of indeterminates over a commutative unitary ring. We study some subrings of the Laurent polynomial rings. We finally obtain two cancellation properties. (author)

  12. Assessment of the reliability of ultrasonic inspection methods

    International Nuclear Information System (INIS)

    Haines, N.F.; Langston, D.B.; Green, A.J.; Wilson, R.

    1982-01-01

    The reliability of NDT techniques has remained an open question for many years. A reliable technique may be defined as one that, when rigorously applied by a number of inspection teams, consistently finds then correctly sizes all defects of concern. In this paper we report an assessment of the reliability of defect detection by manual ultrasonic methods applied to the inspection of thick section pressure vessel weldments. Initially we consider the available data relating to the inherent physical capabilities of ultrasonic techniques to detect cracks in weldment and then, independently, we assess the likely variability in team to team performance when several teams are asked to follow the same specified test procedure. The two aspects of 'capability' and 'variability' are brought together to provide quantitative estimates of the overall reliability of ultrasonic inspection of thick section pressure vessel weldments based on currently existing data. The final section of the paper considers current research programmes on reliability and presents a view on how these will help to further improve NDT reliability. (author)

  13. Analysis of reforming process of large distorted ring in final enlarging forging

    International Nuclear Information System (INIS)

    Miyazawa, Takeshi; Murai, Etsuo

    2002-01-01

    In the construction of reactors or pressure vessels for oil chemical plants and nuclear power stations, mono block open-die forging rings are often utilized. Generally, a large forged ring is manufactured by means of enlarging forging with reductions of the wall thickness. During the enlarging process the circular ring is often distorted and becomes an ellipse in shape. However the shape control of the ring is a complicated work. This phenomenon makes the matter still worse in forging of larger rings. In order to make precision forging of large rings, we have developed the forging method using a v-shape anvil. The v-shape anvil is geometrically adjusted to fit the distorted ring in the final circle and reform automatically the shape of the ring during enlarging forging. This paper has analyzed the reforming process of distorted ring by computer program based on F.E.M. and examined the effect on the precision of ring forging. (author)

  14. Heavy ion storage rings

    International Nuclear Information System (INIS)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented. 35 refs

  15. Faithfully quadratic rings

    CERN Document Server

    Dickmann, M

    2015-01-01

    In this monograph the authors extend the classical algebraic theory of quadratic forms over fields to diagonal quadratic forms with invertible entries over broad classes of commutative, unitary rings where -1 is not a sum of squares and 2 is invertible. They accomplish this by: (1) Extending the classical notion of matrix isometry of forms to a suitable notion of T-isometry, where T is a preorder of the given ring, A, or T = A^2. (2) Introducing in this context three axioms expressing simple properties of (value) representation of elements of the ring by quadratic forms, well-known to hold in

  16. Experimental Study of the Ultrasonic Vibration-Assisted Abrasive Waterjet Micromachining the Quartz Glass

    Directory of Open Access Journals (Sweden)

    Rongguo Hou

    2018-01-01

    Full Text Available The ultrasonic vibration is used to enhance the capability of the abrasive water micromachining glass. And, the ultrasonic vibration is activated on the abrasive waterjet nozzle. The quality of the flow is improved, and the velocity of the abrasive is increased because of the addition of the ultrasonic energy. The relevant experimental results indicate that the erosion depth and the material volume removal of the glass are obviously increased when ultrasonic vibration is working. As for the influence of process parameters on the material removal of the glass such as vibration amplitude, system pressure, distance of the standoff, and abrasive size, the experimental results indicate that the system pressure and vibration contribute greatly to the glass material removal. Also, the erosion depth and the volume of material removal are increased with the increase in the vibration amplitude and system pressure. There are some uplifts found at the edge of erosion pit. Then, it can be inferred that the plastic method is an important material removal method during the machining process of ultrasonic vibration-assisted abrasive waterjet.

  17. Grain fragmentation in ultrasonic-assisted TIG weld of pure aluminum.

    Science.gov (United States)

    Chen, Qihao; Lin, Sanbao; Yang, Chunli; Fan, Chenglei; Ge, Hongliang

    2017-11-01

    Under the action of acoustic waves during an ultrasonic-assisted tungsten inert gas (TIG) welding process, a grain of a TIG weld of aluminum alloy is refined by nucleation and grain fragmentation. Herein, effects of ultrasound on grain fragmentation in the TIG weld of aluminum alloy are investigated via systematic welding experiments of pure aluminum. First, experiments involving continuous and fixed-position welding are performed, which demonstrate that ultrasound can break the grain of the TIG weld of pure aluminum. The microstructural characteristics of an ultrasonic-assisted TIG weld fabricated by fixed-position welding are analyzed. The microstructure is found to transform from plane crystal, columnar crystal, and uniform equiaxed crystal into plane crystal, deformed columnar crystal, and nonuniform equiaxed crystal after application of ultrasound. Second, factors influencing ultrasonic grain fragmentation are investigated. The ultrasonic amplitude and welding current are found to have a considerable effect on grain fragmentation. The degree of fragmentation first increases and then decreases with an increase in ultrasonic amplitude, and it increases with an increase in welding current. Measurement results of the vibration of the weld pool show that the degree of grain fragmentation is related to the intensity of acoustic nonlinearity in the weld pool. The greater the intensity of acoustic nonlinearity, the greater is the degree of grain fragmentation. Finally, the mechanism of ultrasonic grain fragmentation in the TIG weld of pure aluminum is discussed. A finite element simulation is used to simulate the acoustic pressure and flow in the weld pool. The acoustic pressure in the weld pool exceeds the cavitation threshold, and cavitation bubbles are generated. The flow velocity in the weld pool does not change noticeably after application of ultrasound. It is concluded that the high-pressure conditions induced during the occurrence of cavitation, lead to grain

  18. Numerical Analysis of Ultrasonic Beam Profile Due to the Change of the Number of Piezoelectric Elements for Phased Array Transducer

    International Nuclear Information System (INIS)

    Choi, Sang Woo; Lee, Joon Hyun

    1999-01-01

    A phased array is a multi-element piezoelectric device whose elements are individually excited by electric pulses at programmed delay time. One of the advantages of using phased array in nondestructive evaluation (NDE) application over conventional ultrasonic transducers is their great maneuverability of ultrasonic beam. There are some parameters such as the number and the size of the piezoelectric elements and the inter-element spacing of the elements to design phased array transducer. In this study, the characteristic of ultrasonic beam for phased array transducer due to the variation of the number of elements has been simulated for ultrasonic SH-wave on the basis of Huygen's principle. Ultrasonic beam directivity and focusing due to the change of time delay of each element were discussed due to the change of the number of piezoelectric elements. It was found that ultrasonic beam was much more spreaded and hence its sound pressure was decreased as steering angle of ultrasonic beam was increased. In addition, the ability of ultrasonic bean focusing decreased gradually with the increase of focal length at the same piezoelectric elements. However, the ability of beam focusing was improved as the number of consisting elements was increased

  19. Heliotropic dust rings for Earth climate engineering

    Science.gov (United States)

    Bewick, R.; Lücking, C.; Colombo, C.; Sanchez, J. P.; McInnes, C. R.

    2013-04-01

    This paper examines the concept of a Sun-pointing elliptical Earth ring comprised of dust grains to offset global warming. A new family of non-Keplerian periodic orbits, under the effects of solar radiation pressure and the Earth's J2 oblateness perturbation, is used to increase the lifetime of the passive cloud of particles and, thus, increase the efficiency of this geoengineering strategy. An analytical model is used to predict the orbit evolution of the dust ring due to solar-radiation pressure and the J2 effect. The attenuation of the solar radiation can then be calculated from the ring model. In comparison to circular orbits, eccentric orbits yield a more stable environment for small grain sizes and therefore achieve higher efficiencies when the orbit decay of the material is considered. Moreover, the novel orbital dynamics experienced by high area-to-mass ratio objects, influenced by solar radiation pressure and the J2 effect, ensure the ring will maintain a permanent heliotropic shape, with dust spending the largest portion of time on the Sun facing side of the orbit. It is envisaged that small dust grains can be released from a circular generator orbit with an initial impulse to enter an eccentric orbit with Sun-facing apogee. Finally, a lowest estimate of 1 × 1012 kg of material is computed as the total mass required to offset the effects of global warming.

  20. A feasiblity study of an ultrasonic test phantom arm

    Science.gov (United States)

    Schneider, Philip

    This thesis is a feasibility study for the creation of a test phantom that replicates the physiological features, from an acoustic and mechanical standpoint, of that of a human arm. Physiological feature set includes; Heart, Arteries, Veins, Bone, Muscle, Fat, Skin, and Dermotographic Features (finger prints). Mechanical Aspects include, vascular compression and distention, elasticity of tissue layers, mechanics of human heart. The end goal of which to have a working understanding of each component in order to create a controllable, real time, physiologically accurate, test phantom for a wide range of ultrasonic based applications. These applications can range from devices like wearable technologies to medical training, to biometric "Liveness" detection methods. The proposed phantom would allow for a number of natural bodily functions to be measured including but not limited to vascular mapping, blood pressure, heart rate, subdermal imaging, and general ultrasonic imaging.

  1. Reactor vessel and core two-phase flow ultrasonic densitometer

    International Nuclear Information System (INIS)

    Arave, A.E.

    1979-01-01

    A local ultrasonic density (LUD) detector has been developed by EG and G Idaho, Inc., at the Idaho National Engineering Laboratory (INEL) for the Loss-of-Fluid Test (LOFT) reactor vessel and core two-phase flow density measurements. The principle of operating the sensor is the change in propagation time of a torsional ultrasonic wave in a metal transmission line as a function of the density of the surrounding media. A theoretical physics model is presented which represents the total propagation time as a function of the sensor modulus of elasticity and polar moment of inertia. Separate effects tests and two-phase flow tests have been conducted to characterize the detector. Tests show the detector can perform in a 343 0 C pressurized water reactor environment and measure the average density of the media surrounding the sensor

  2. Use of ultrasonic waves in sub-cooled boiling

    International Nuclear Information System (INIS)

    Bartoli, Carlo; Baffigi, Federica

    2012-01-01

    This work focuses on the use of ultrasounds in heat transfer fields. Under particular conditions, ultrasonic waves induce a convection coefficient increase. This initial research work, indicates that there are some practical applications in the cooling of the latest generation electronic components. In the first part of this paper, some background on this subject is reported. The ultrasound's influence on heat transfer rate has been observed since the 60's: different authors studied the cooling effect due to ultrasonic waves from different heat transfer regimes. The most investigated configuration was a thin platinum wire immersed in water. Later, a bibliographic research on possible practical applications of ultrasounds was carried out. This research focused in particular on the issue for 3D highly integrated electronic components. For these systems the thermal problem is a major challenge, because they cannot exceed critical temperatures, after which they could be damaged irreversibly. On the basis of our experimental results, ultrasounds could represent a valid means to overcome these thermal problems. Finally, the paper presents a series of experiments performed in the Thermal-Fluid- Dynamic Lab at the Energy and Engineering Systems Department of University of Pisa. The experiments provide systematic evidence of ultrasonic waves effects, on free convection heat transfer, from a heated circular cylinder to sub-cooled water, at atmospheric pressure. Many variables involved in the heat transfer rise were tested, for example: the ultrasonic generator's power, the position of the heater inside the ultrasonic tank, the variation of the water sub-cooling degree, as function of the heat flux needed dissipating. The aim of the experiment was to find out the set of optimal conditions, in order to successively apply all the results to real packaging systems, as mentioned before. The maximum increase in the heat transfer coefficient, due to ultrasonic waves, was 57

  3. Test Accumulation Ring for NUMATRON Project - TARN -

    International Nuclear Information System (INIS)

    Hirao, Y.; Chida, K.; Hattori, T.; Hori, T.; Katayama, T.

    1979-03-01

    TARN is now under construction at INS, University of Tokyo. Heavy ions from the SF Cyclotron such as N 5+ with an energy of 8.5 MeV per nucleon, are planned to be injected and stacked in the ring by a combination of multiturn injection and RF stacking method. Expected intensity of the stacked beam, e.g. N 5+ , is 2 x 10 10 particles, and survival rate of 90% is anticipated at the pressure of 1 x 10 -10 torr during a stacking time of 1 sec. In this paper the present status of the ring is described as well as the performances of the major subsystems. (author)

  4. Evaluation of radiation-induced degradation of silicon '0' ring

    International Nuclear Information System (INIS)

    Ikeshima, Yoshiaki; Shiraishi; Tadao; Sato, Ryuichi; Tanaka, Isao; Ichihashi, Yoshinori; Ito, Masayuki.

    1990-12-01

    Currently there is too few available data on mechanical properties of an 'O' ring made of organic material, which is used over an extensive period of time under actual Nuclear Reactor environmental conditions. The 'O' rings which were evaluated were made of Silicon Rubber, and are used to provide water tightness. The 'O' rings also served as a pressure boundary within the nozzle of the in-reactor tube in the Water Loop-2 (OWL-2) at the JMTR in Oarai, Ibaraki. The 'O' rings were subjected to a constant penetrating radiation (up to 3.46 kGy) over a period of thirteen (13) years. The effects on the mechanical properties of a Silicon Rubber 'O' Ring were evaluated after having been used over an extensive period of time in an actual in-reactor tube within a radiation environment; a full thirteen years in durations. In making comparison of the properties of other Silicon Rubber 'O' Rings. It was also found that these other 'O' rings were subject to Gamma Rays for a shorter period, but with the same amount of radiation as the 'O' rings in the reactor were supposedly to have received. The evaluation showed that a Silicon Rubber 'O' Ring could have been used for a period, as much as forty (40) years even with a (absorbed) dose of about 300 kGy, before the life expectancy of such an 'O' ring is fully met. It was also discovered that the mechanical properties of an Ethylene Propylene 'O' Rings (currently used in the new OWL-2 in-reactor tube) were much superior to those of the Silicon Rubber 'O' Rings. The Ethylene Propylene 'O' Rings had a live expectancy which was about three times that of a Silicon Rubber 'O' Rings. (author)

  5. New graft sizing rings for aortic valve reimplantation procedures.

    Science.gov (United States)

    Jelenc, Matija; Jelenc, Blaž; Kneževic, Ivan; Klokocovnik, Tomislav

    2018-01-01

    The objective was to design sizing rings that would enable proper sizing of the graft in reimplantation procedures and to perform leaflet repair before graft implantation. The rings were designed in Autodesk Fusion 360 (San Rafael, CA, USA) and 3D printed using a commercial online 3D printing service. We designed incomplete rings with a low profile and complete rings with a high profile. The complete rings are best suited for reimplantation procedures, whereas low profile C rings are intended for isolated aortic valve repair, where the ascending aorta is not transected. The rings come in sizes corresponding to Vascutek Gelweave graft sizes (Vascutek Terumo, Renfrewshire, Scotland). The ring internal diameters are 5% larger than the designated ring sizes and account for the 5% stretch of the grafts when pressurized. Blades of the rings are placed at 20° intervals. The slits between the blades are designed in such a way that the commissural U-sutures, when put in place and under tension, will lock the ring in position. The rings were successfully used in 10 of our latest reimplantation procedures. After dissection of the aortic root, the commissures were suspended with U-stitches and then the ring was seated onto them. Complete leaflet repair with plication to achieve adequate effective height was then performed, followed by graft implantation. No additional leaflet repair was needed. The newly designed sizing rings enable proper sizing of the graft in reimplantation procedures and enable complete leaflet repair before graft implantation. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  6. On arbitrarily graded rings

    Indian Academy of Sciences (India)

    58

    paper is devoted to the study of arbitrary rings graded through arbitrary sets. .... which recover certain multiplicative relations among the homogeneous components ... instance the case in which the grading set A is an Abelian group, where the ...

  7. The g-2 ring

    CERN Multimedia

    1974-01-01

    The precise measurement of "g-2", the anomalous magnetic moment of the muon, required a special muon storage ring with electrostatic focussing and very accurate knowledge of the magnetic bending field. For more details see under photo 7405430.

  8. Ultrasonic assisted extraction - an alternative for sample preparation (M4)

    International Nuclear Information System (INIS)

    Santos Junior, P.; Barbosa Junior, F.; Krug, F.J.; Trevizan, L.C.; Nobrega, J.A.

    2002-01-01

    Full text: In the last years the ultrasound assisted metal extraction has been frequency proposed as a simple and inexpensive alternative for sample preparation of biological and inorganic samples. The extraction effect is considered as being caused by acoustic cavitation, that is, bubble formation and subsequent disruptive action. The collapse of bubbles created by sonication of solutions results in the generation of extremely high local temperature and pressure gradients, which may be regarded as localized 'hot spots'. On a timescale of about 10 -10 s, effective local pressures and temperature of about 10 5 atm and about 5000 K, respectively, are generated under sonochemical conditions. Usually, this method uses a diluted acid medium decreasing blank values and reducing both reagents and time consumption compared to traditional wet digestion systems using conductive or microwave-assisted heating. Furthermore, sonication can also allow the preparation of samples directly within the sample container, thereby preventing sample losses and minimizing sample contamination. Although some controversial results concerning metals extraction behavior have been reported, they could be explained by analyte-matrix interaction and the ability of the ultrasonic processor to generate ultrasound (i.e. the use of an ultrasonic bath or an ultrasonic probe at different power, frequency, and amplitude). This contribution presents a review of ultrasound assisted metal extraction and recent performance data obtained in our laboratory for determination of elements in biological materials, soils and sediments by ICP-OES and ETAAS. The effect of extraction parameters, such as type and concentration of the leaching solution, sonication time and performance of ultrasonic processor (bath or probe) will be presented. (author)

  9. A new approach to ultrasonic elasticity imaging

    Science.gov (United States)

    Hoerig, Cameron; Ghaboussi, Jamshid; Fatemi, Mostafa; Insana, Michael F.

    2016-04-01

    Biomechanical properties of soft tissues can provide information regarding the local health status. Often the cells in pathological tissues can be found to form a stiff extracellular environment, which is a sensitive, early diagnostic indicator of disease. Quasi-static ultrasonic elasticity imaging provides a way to image the mechanical properties of tissues. Strain images provide a map of the relative tissue stiffness, but ambiguities and artifacts limit its diagnostic value. Accurately mapping intrinsic mechanical parameters of a region may increase diagnostic specificity. However, the inverse problem, whereby force and displacement estimates are used to estimate a constitutive matrix, is ill conditioned. Our method avoids many of the issues involved with solving the inverse problem, such as unknown boundary conditions and incomplete information about the stress field, by building an empirical model directly from measured data. Surface force and volumetric displacement data gathered during imaging are used in conjunction with the AutoProgressive method to teach artificial neural networks the stress-strain relationship of tissues. The Autoprogressive algorithm has been successfully used in many civil engineering applications and to estimate ocular pressure and corneal stiffness; here, we are expanding its use to any tissues imaged ultrasonically. We show that force-displacement data recorded with an ultrasound probe and displacements estimated at a few points in the imaged region can be used to estimate the full stress and strain vectors throughout an entire model while only assuming conservation laws. We will also demonstrate methods to parameterize the mechanical properties based on the stress-strain response of trained neural networks. This method is a fundamentally new approach to medical elasticity imaging that for the first time provides full stress and strain vectors from one set of observation data.

  10. [Liesegang's rings resembling helminthiasis].

    Science.gov (United States)

    Zámecník, M; Riedl, I

    1996-12-01

    So called Liesegang's rings are lamellar corpuscles which develop after periodical precipitation of oversaturated solutions in gel medium. They can occur in cysts, closed cavities, inflammatory exudates and necroses. They resemble parasitic eggs, larvae or adult forms. A case of 28-year-old woman is presented with many Liesegang's rings in a stuff from dilated renal calyx. Their preliminary evaluation considered helminths, especially Dioctophyma renale.

  11. Storage ring group summary

    International Nuclear Information System (INIS)

    King, N.M.

    1980-01-01

    The Storage Ring Group set out to identify and pursue salient problems in accelerator physics for heavy ion fusion, divorced from any particular reference design concept. However, it became apparent that some basic parameter framework was required to correlate the different study topics. As the Workshop progressed, ring parameters were modified and updated. Consequently, the accompanying papers on individual topics will be found to refer to slightly varied parameters, according to the stage at which the different problems were tackled

  12. The rings of Uranus

    Science.gov (United States)

    Elliot, J. L.; Dunham, E.; Mink, D.

    1977-01-01

    A description is given of the observation of five brief occultations of the star SAO 158687 which occurred both before and after its occultation by Uranus on March 10, 1977. The events were observed with a three-channel occultation photometer, attached to a 91-cm telescope. The observations indicate that at least five rings encircle the planet Uranus. Possible reasons for the narrowness of the Uranus rings are discussed.

  13. Newly developed non-destructive testing method for evaluation of irradiation brittleness of structural materials using ultrasonic

    International Nuclear Information System (INIS)

    Ishii, Toshimitsu; Ooka, Norikazu; Kato, Yoshiaki; Saito, Junichi; Hoshiya, Taiji; Shibata, Saburo; Kobayashi, Hideo

    1999-01-01

    Surveillance testing is important to evaluate neutron irradiation embrittlement of reactor pressure vessel material for long life operation. An alternative test method for evaluating the irradiation embrittlement of the pressure vessel material will have to be proposed to support the limited number of surveillance test specimens in order to manage the plant life to be extended. In this study, ultrasonic testing for irradiated A533B-1 steel and weld metal was applied to examine material degradation nondestructively. With increasing the shift of Charpy 41 J transition temperature, ultrasonic velocity decreased and attenuation coefficient of ultrasonic wave increased. Especially, the difference of ultrasonic velocity for 5 MHz shear wave between as-received and irradiated material is corresponding to the shift of transition temperature showing material degradation. (author)

  14. Study on Method of Ultrasonic Gas Temperature Measure Based on FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Wen, S H; Xu, F R [Institute of Electrical Engineering, Yanshan University, Qinhuangdao, 066004 (China)

    2006-10-15

    It is always a problem to measure instantaneous temperature of high-temperature and high-pressure gas. There is difficulty for the conventional method of measuring temperature to measure quickly and exactly, and the measuring precision is low, the ability of anti-jamming is bad, etc. So the article introduces a method of measuring burning gas temperature using ultrasonic based on Field-Programmable Gate Array (FPGA). The mathematic model of measuring temperature is built with the relation of velocity of ultrasonic transmitting and gas Kelvin in the ideal gas. The temperature can be figured out by measuring the difference of ultrasonic frequency {delta}f. FPGA is introduced and a high-precision data acquisition system based on digital phase-shift technology is designed. The feasibility of proposed above is confirmed more by measuring pressure of burning gas timely. Experimental result demonstrates that the error is less than 12.. and the precision is heightened to 0.8%.

  15. A study of weld quality in ultrasonic spot welding of similar and dissimilar metals

    International Nuclear Information System (INIS)

    Al-Sarraf, Z; Lucas, M

    2012-01-01

    Several difficulties are faced in joining thinner sheets of similar and dissimilar materials from fusion welding processes such as resistance welding and laser welding. Ultrasonic metal welding overcomes many of these difficulties by using high frequency vibration and applied pressure to create a solid-state weld. Ultrasonic metal welding is an effective technique in joining small components, such as in wire bonding, but is also capable of joining thicker sheet, depending on the control of welding conditions. This study presents the design, characterisation and test of a lateral-drive ultrasonic metal welding device. The ultrasonic welding horn is modelled using finite element analysis and its vibration behaviour is characterised experimentally to ensure ultrasonic energy is delivered to the weld coupon. The welding stack and fixtures are then designed and mounted on a test machine to allow a series of experiments to be conducted for various welding and ultrasonic parameters. Weld strength is subsequently analysed using tensile-shear tests. Control of the vibration amplitude profile through the weld cycle is used to enhance weld strength and quality, providing an opportunity to reduce part marking. Optical microscopic examination and scanning electron microscopy (SEM) were employed to investigate the weld quality. The results show how the weld quality is particularly sensitive to the combination of clamping force and vibration amplitude of the welding tip.

  16. Facile nanofibrillation of chitin derivatives by gas bubbling and ultrasonic treatments in water.

    Science.gov (United States)

    Tanaka, Kohei; Yamamoto, Kazuya; Kadokawa, Jun-ichi

    2014-10-29

    In this paper, we report that nanofiber network structures were constructed from chitin derivatives by gas bubbling and ultrasonic treatments in water. When chitin was first subjected to N2 gas bubbling with ultrasonication in water, the SEM images of the product showed nanofiber network morphology. However, nanofiber network was not re-constructed by the same N2 gas bubbling and ultrasonic treatments after agglomeration. We then have paid attention to an amidine group to provide the agglomeration-nanofibrillation behavior of chitin derivatives. An amidinated chitin was synthesized by the reaction of the amino groups in a partially deacetylated chitin with N,N-dimethylacetamide dimethyl acetal, which was subjected to CO2 gas bubbling and ultrasonic treatments in water to convert into an amidinium chitin by protonation. The SEM images of the product clearly showed nanofiber network morphology. We further examined re-nanofibrillation of the agglomerated material, which was obtained by mixing the nanofibrillated amidinium chitin with water, followed by drying under reduced pressure. Consequently, the material was re-nanofibrillated by N2 gas bubbling with ultrasonication in water owing to electrostatic repulsion between the amidinium groups. Furthermore, deprotonation of the amidinium chitin and re-protonation of the resulting amidinated chitin were conducted by alkaline treatment and CO2 gas bubbling-ultrasonic treatments, respectively. The material showed the agglomeration-nanofibrillation behavior during the processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. An extended model for ultrasonic-based enhanced oil recovery with experimental validation.

    Science.gov (United States)

    Mohsin, Mohammed; Meribout, Mahmoud

    2015-03-01

    This paper suggests a new ultrasonic-based enhanced oil recovery (EOR) model for application in oil field reservoirs. The model is modular and consists of an acoustic module and a heat transfer module, where the heat distribution is updated when the temperature rise exceeds 1 °C. The model also considers the main EOR parameters which includes both the geophysical (i.e., porosity, permeability, temperature rise, and fluid viscosity) and acoustical (e.g., acoustic penetration and pressure distribution in various fluids and mediums) properties of the wells. Extended experiments were performed using powerful ultrasonic waves which were applied for different kind of oils & oil saturated core samples. The corresponding results showed a good matching with those obtained from simulations, validating the suggested model to some extent. Hence, a good recovery rate of around 88.2% of original oil in place (OOIP) was obtained after 30 min of continuous generation of ultrasonic waves. This leads to consider the ultrasonic-based EOR as another tangible solution for EOR. This claim is supported further by considering several injection wells where the simulation results indicate that with four (4) injection wells; the recovery rate may increase up-to 96.7% of OOIP. This leads to claim the high potential of ultrasonic-based EOR as compared to the conventional methods. Following this study, the paper also proposes a large scale ultrasonic-based EOR hardware system for installation in oil fields. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Ultrasonic Linear Motor with Two Independent Vibrations

    Science.gov (United States)

    Muneishi, Takeshi; Tomikawa, Yoshiro

    2004-09-01

    We propose a new structure of an ultrasonic linear motor in order to solve the problems of high-power ultrasonic linear motors that drive the XY-stage for electron beam equipment and to expand the application fields of the motor. We pay special attention to the following three points: (1) the vibration in two directions of the ultrasonic linear motor should not influence mutually each other, (2) the vibration in two directions should be divided into the stage traveling direction and the pressing direction of the ultrasonic linear motor, and (3) the rigidity of the stage traveling direction of the ultrasonic linear motor should be increased. As a result, the supporting method of ultrasonic linear motors is simplified. The efficiency of the motor is improved and temperature rise is reduced. The stage position drift is also improved.

  19. Effect of Ultrasonic Frequency on Lactic Acid Fermentation Promotion by Ultrasonic Irradiation

    Science.gov (United States)

    Shimada, Tadayuki; Ohdaira, Etsuzo; Masuzawa, Nobuyoshi

    2004-05-01

    The authors have been researching the promotion of lactic acid fermentation by ultrasonic irradiation. In the past research, it was proven that ultrasonic irradiation is effective in the process of fermentation, and the production of yoghurt and kefir was promoted. In this study, the effect of the ultrasonic frequency in this fermentation process was examined. In the frequency range of this study, it was found that the action of fermentation promotion was exponentially proportionate to the irradiated ultrasonic frequency.

  20. Ultrasonic inspection of austenitic welds

    Energy Technology Data Exchange (ETDEWEB)

    Tomlinson, J R; Wagg, A R; Whittle, M J [N.D.T. Applications Centre, CEGB, Manchester (United Kingdom)

    1980-11-01

    The metallurgical structure of austenitic welds is described and contrasted with that found in ferritic welds. It is shown that this structure imparts a marked elastic anisotropy in the ultrasonic propagation parameters. Measurements of variations in the apparent attenuation of sound and deviations in the beam direction are described. The measurements are interpreted in terms of the measured velocity anisotropy. Two applications of the fundamental work are described. In the first it is shown how, by using short pulse compression wave probes, and with major modification of the welding procedure, a stainless steel fillet weld in an AGR boiler can be inspected. In the second application, alternative designs of a transition butt weld have been compared for ease of ultrasonic inspection. The effects of two different welding processes on such an inspection are described. Finally, the paper examines the prospects for future development of inspection and defect-sizing techniques for austenitic welds. (author)

  1. Numerical modeling of ultrasonic cavitation in ionic liquids

    Science.gov (United States)

    Calvisi, Michael L.; Elder, Ross M.

    2017-11-01

    Ionic liquids have favorable properties for sonochemistry applications in which the high temperatures and pressures achieved by cavitation bubbles are important drivers of chemical processes. Two different numerical models are presented to simulate ultrasonic cavitation in ionic liquids, each with different capabilities and physical assumptions. A model based on a compressible form of the Rayleigh-Plesset equation (RPE) simulates ultrasonic cavitation of a spherical bubble with a homogeneous interior, incorporating evaporation and condensation at the bubble surface, and temperature-varying thermodynamic properties in the interior. A second, more computationally intensive model of a spherical bubble uses the finite element method (FEM) and accounts for spatial variations in pressure and temperature throughout the flow domain. This model provides insight into heat transfer across the bubble surface and throughout the bubble interior and exterior. Parametric studies are presented for sonochemistry applications involving ionic liquids as a solvent, examining a range of realistic ionic liquid properties and initial conditions to determine their effect on temperature and pressure. Results from the two models are presented for parametric variations including viscosity, thermal conductivity, water content of the ionic liquid solvent, acoustic frequency, and initial bubble pressure. An additional study performed with the FEM model examines thermal penetration into the surrounding ionic liquid during bubble oscillation. The results suggest the prospect of tuning ionic liquid properties for specific applications.

  2. Proposed new ultrasonic test bed

    International Nuclear Information System (INIS)

    Maxfield, B.W.

    1978-01-01

    Within the last four or five years, a great deal of progress has been made both here and in a number of other laboratories in developing techniques that will enable considerably more information to be obtained from the ultrasonic examination of an object. Some of these recent developments relate to information contained within the diffracted beam which does not return along the incident path. An ultrasonic examination based upon an evaluation of diffracted energy must use at least two transducers, one for transmission and the other for reception. Current indications are that even more reliable test results will be achieved using a receiving transducer that can scan a significant portion of the diffracted field including that portion which is back-reflected. In general, this scan can be interpreted most accurately if it follows a path related to the surface shape. If more than one region within the object is to be interrogated, then the transmitting transducer must also be scanned, again along a path related to the surface shape. The large quantity of information obtained as the result of such an examination must be subjected to sophisticated computer analysis in order to be displayed in a meaningful and intelligible manner. Although one motivation for building such an instrument is to explore new ultrasonic test procedures that are evolving from current laboratory research, this is neither the sole motivation nor the only use for this instrument. Such a mechanical and electronic device would permit conventional ultrasonic tests to be performed on parts of complex geometry without the expensive and time-consuming special fixturing that is currently required. May possible test geometries could be explored in practice prior to the construction of a specialized test apparatus. Hence, it would be necessary to design much, if any, flexibility into the special test apparatus

  3. Ultrasonic sizing of fatigue cracks

    International Nuclear Information System (INIS)

    Burns, D.J.

    1983-12-01

    Surface and buried fatigue cracks in steel plates have been sized using immersion probes as transmitters-receivers, angled to produce shear waves in the steel. Sizes have been estimated by identifying the ultrasonic waves diffracted from the crack tip and by measuring the time taken for a signal to travel to and from the crack tip. The effects of compression normal to a fatigue crack and of crack front curvature are discussed. Another diffraction technique, developed by UKAEA, Harwell, is reviewed

  4. Some Aspects of Ring Theory

    CERN Document Server

    Herstein, IN

    2011-01-01

    S. Amitsur: Associative rings with identities.- I.N. Herstein: Topics in ring theory.- N. Jacobson: Representation theory of Jordan algebras.- I. Kaplansky: The theory of homological dimension.- D. Buchsbaum: Complexes in local ring theory.- P.H. Cohn: Two topics in ring theory.- A.W. Goldie: Non-commutative localisation.

  5. Ultrasonic characterization of yogurt fermentation process

    OpenAIRE

    IZBAIM , DRIS; FAIZ , BOUAZZA; MOUDDEN , ALI; MALAININE , MOHAMED; ABOUDAOUD , Idriss

    2012-01-01

    International audience; The objective of this work is to characterize the fermentation of yogurt based on an ultrasonic technique. Conventionally, the acidity of the yogurt is measured by a pH meter to determine the progress of fermentation. However, the pH meter should be cleaned and calibrated for each measurement and, therefore, this method is not practical. In this regard, ultrasonic techniques are fast, non-invasive and inexpensive. The measurement of ultrasonic parameters such as amplit...

  6. Experimental investigation of ultrasonic velocity anisotropy in ...

    Indian Academy of Sciences (India)

    Permanent link: https://www.ias.ac.in/article/fulltext/pram/077/02/0345-0355. Keywords. Magnetic fluids; ultrasonic wave; sound velocity; anisotropy. Abstract. Magnetic field-induced dispersion of ultrasonic velocity in a Mn0.7Zn0.3Fe2O4 fluid (applied magnetic field is perpendicular to the ultrasonic propagation vector) is ...

  7. Automated ultrasonic inspection using PULSDAT

    International Nuclear Information System (INIS)

    Naybour, P.J.

    1992-01-01

    PULSDAT (Portable Ultrasonic Data Acquisition Tool) is a system for recording the data from single probe automated ultrasonic inspections. It is one of a range of instruments and software developed by Nuclear Electric to carry out a wide variety of high quality ultrasonic inspections. These vary from simple semi-automated inspections through to multi-probe, highly automated ones. PULSDAT runs under the control of MIPS software, and collects data which is compatible with the GUIDE data display system. PULSDAT is therefore fully compatible with Nuclear Electric's multi-probe inspection systems and utilises all the reliability and quality assurance of the software. It is a rugged, portable system that can be used in areas of difficult access. The paper discusses the benefits of automated inspection and gives an outline of the main features of PULSDAT. Since April 1990 PULSDAT has been used in several applications within Nuclear Electric and this paper presents two examples: the first is a ferritic set-through nozzle and the second is an austenitic fillet weld. (Author)

  8. Ring correlations in random networks.

    Science.gov (United States)

    Sadjadi, Mahdi; Thorpe, M F

    2016-12-01

    We examine the correlations between rings in random network glasses in two dimensions as a function of their separation. Initially, we use the topological separation (measured by the number of intervening rings), but this leads to pseudo-long-range correlations due to a lack of topological charge neutrality in the shells surrounding a central ring. This effect is associated with the noncircular nature of the shells. It is, therefore, necessary to use the geometrical distance between ring centers. Hence we find a generalization of the Aboav-Weaire law out to larger distances, with the correlations between rings decaying away when two rings are more than about three rings apart.

  9. Recent progress in online ultrasonic process monitoring

    Science.gov (United States)

    Wen, Szu-Sheng L.; Chen, Tzu-Fang; Ramos-Franca, Demartonne; Nguyen, Ky T.; Jen, Cheng-Kuei; Ihara, Ikuo; Derdouri, A.; Garcia-Rejon, Andres

    1998-03-01

    On-line ultrasonic monitoring of polymer co-extrusion and gas-assisted injection molding are presented. During the co- extrusion of high density polyethylene and Santoprene ultrasonic sensors consisting of piezoelectric transducers and clad ultrasonic buffer rods are used to detect the interface between these two polymers and the stability of the extrusion. The same ultrasonic sensor also measures the surface temperature of the extruded polymer. The results indicate that temperature measurements using ultrasound have a faster response time than those obtained by conventional thermocouple. In gas-assisted injection molding the polymer and gas flow front positions are monitored simultaneously. This information may be used to control the plunger movement.

  10. Internal ultrasonic inspection of flexible pipe

    Energy Technology Data Exchange (ETDEWEB)

    Baltzersen, O. (IKU Petroleumsforskning A/S, Trondheim (Norway) Norwegian Inst. of Tech., Trondheim (Norway). Div. of Petroleum Engineering and Applied Geophysics); Waag, T.I. (IKU Petroleumsforskning A/S, Trondheim (Norway))

    1993-10-01

    Methods for internal ultrasonic inspection of flexible pipe have been investigated through experiments with a short sample of Coflexip pipe. Ultrasonic backscatter methods using normal and non-normal incidence have been used for qualitative high contrast ultrasonic imaging of the inner surface of the pipe. Analysis of the internal cross-section has been performed based on the use of a non-contact ultrasonic caliper, and processing procedures which enable calculation of, and compensation for, eccentricity of the tool in the pipe. The methods developed can be used to quantitatively estimate the thickness of the internal carcass, and perform high resolution topographic mapping of the inner surface. (Author)

  11. Under sodium ultrasonic imaging system for PFBR

    International Nuclear Information System (INIS)

    Patankar, V.H.; Lalwani, S.K.; Agashe, A.A.

    2014-01-01

    Under Sodium UltraSonic Scanner (USUSS) has been developed to detect the growth and protrusion of fuel sub-assemblies of PFBR, submerged in liquid sodium by using the ultrasonic imaging technique during reactor shut-down when liquid sodium is at 180 ℃. The imaging is carried out prior to every Fuel handling operation. Electronics Division, BARC has designed and developed an 8-Channel Ultrasonic Imaging System (UIS) which consists of 4 downward viewing and 4 side viewing ultrasonic transducers alongwith pulser-receiver, signal processing electronics hardware and software. An automated mechanical scanner developed by IGCAR houses sodium immersible transducers to image the fuel sub assemblies. The system has been successfully tested with dummy protruding and grown FSAs, submerged under liquid sodium. Such ultrasonic imaging systems are not available to India from international market. The USUSS developed indigenously has all the features available in similar systems developed by other countries. After every imaging campaign, the mechanical scanner containing ultrasonic transducers is stored in the Argon filled storage-pit. Before every campaign of USUSS, it is necessary to check the healthiness of the sodium immersible and contaminated ultrasonic transducers, as the under-sodium scanner is decontaminated once in five years. For this purpose, a novel Non Contact Ultrasonic Inspection System (NCUIS) has been designed and developed by Electronics Division, BARC to check the functionality of the high-temperature and contaminated transducers of USUSS, using air-coupled ultrasonic technique. (author)

  12. Stresses in ultrasonically assisted bone cutting

    International Nuclear Information System (INIS)

    Alam, K; Mitrofanov, A V; Silberschmidt, V V; Baeker, M

    2009-01-01

    Bone cutting is a frequently used procedure in the orthopaedic surgery. Modern cutting techniques, such as ultrasonic assisted drilling, enable surgeons to perform precision operations in facial and spinal surgeries. Advanced understanding of the mechanics of bone cutting assisted by ultrasonic vibration is required to minimise bone fractures and to optimise the technique performance. The paper presents results of finite element simulations on ultrasonic and conventional bone cutting analysing the effects of ultrasonic vibration on cutting forces and stress distribution. The developed model is used to study the effects of cutting and vibration parameters (e.g. amplitude and frequency) on the stress distributions in the cutting region.

  13. Mapping Ring Particle Cooling across Saturn's Rings with Cassini CIRS

    Science.gov (United States)

    Brooks, Shawn M.; Spilker, L. J.; Edgington, S. G.; Pilorz, S. H.; Deau, E.

    2010-10-01

    Previous studies have shown that the rings' thermal inertia, a measure of their response to changes in the thermal environment, varies from ring to ring. Thermal inertia can provide insight into the physical structure of Saturn's ring particles and their regoliths. Low thermal inertia and quick temperature responses are suggestive of ring particles that have more porous or fluffy regoliths or that are riddled with cracks. Solid, coherent particles can be expected to have higher thermal inertias (Ferrari et al. 2005). Cassini's Composite Infrared Spectrometer has recorded millions of spectra of Saturn's rings since its arrival at Saturn in 2004 (personal communication, M. Segura). CIRS records far infrared radiation between 10 and 600 cm-1 (16.7 and 1000 µm) at focal plane 1 (FP1), which has a field of view of 3.9 mrad. Thermal emission from Saturn's rings peaks in this wavelength range. FP1 spectra can be used to infer ring temperatures. By tracking how ring temperatures vary, we can determine the thermal inertia of the rings. In this work we focus on CIRS observations of the shadowed portion of Saturn's rings. The thermal budget of the rings is dominated by the solar radiation absorbed by its constituent particles. When ring particles enter Saturn's shadow this source of energy is abruptly cut off. As a result, ring particles cool as they traverse Saturn's shadow. From these shadow observations we can create cooling curves at specific locations across the rings. We will show that the rings' cooling curves and thus their thermal inertia vary not only from ring to ring, but by location within the individual rings. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.

  14. The cryogenic storage ring CSR

    Science.gov (United States)

    von Hahn, R.; Becker, A.; Berg, F.; Blaum, K.; Breitenfeldt, C.; Fadil, H.; Fellenberger, F.; Froese, M.; George, S.; Göck, J.; Grieser, M.; Grussie, F.; Guerin, E. A.; Heber, O.; Herwig, P.; Karthein, J.; Krantz, C.; Kreckel, H.; Lange, M.; Laux, F.; Lohmann, S.; Menk, S.; Meyer, C.; Mishra, P. M.; Novotný, O.; O'Connor, A. P.; Orlov, D. A.; Rappaport, M. L.; Repnow, R.; Saurabh, S.; Schippers, S.; Schröter, C. D.; Schwalm, D.; Schweikhard, L.; Sieber, T.; Shornikov, A.; Spruck, K.; Sunil Kumar, S.; Ullrich, J.; Urbain, X.; Vogel, S.; Wilhelm, P.; Wolf, A.; Zajfman, D.

    2016-06-01

    An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm-3 is derived, equivalent to a room-temperature pressure below 10-14 mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

  15. The cryogenic storage ring CSR.

    Science.gov (United States)

    von Hahn, R; Becker, A; Berg, F; Blaum, K; Breitenfeldt, C; Fadil, H; Fellenberger, F; Froese, M; George, S; Göck, J; Grieser, M; Grussie, F; Guerin, E A; Heber, O; Herwig, P; Karthein, J; Krantz, C; Kreckel, H; Lange, M; Laux, F; Lohmann, S; Menk, S; Meyer, C; Mishra, P M; Novotný, O; O'Connor, A P; Orlov, D A; Rappaport, M L; Repnow, R; Saurabh, S; Schippers, S; Schröter, C D; Schwalm, D; Schweikhard, L; Sieber, T; Shornikov, A; Spruck, K; Sunil Kumar, S; Ullrich, J; Urbain, X; Vogel, S; Wilhelm, P; Wolf, A; Zajfman, D

    2016-06-01

    An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm(-3) is derived, equivalent to a room-temperature pressure below 10(-14) mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

  16. The cryogenic storage ring CSR

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R. von; Becker, A.; Berg, F.; Blaum, K.; Fadil, H.; Fellenberger, F.; Froese, M.; George, S.; Göck, J.; Grieser, M.; Grussie, F.; Guerin, E. A.; Herwig, P.; Karthein, J.; Krantz, C.; Kreckel, H.; Lange, M.; Laux, F.; Lohmann, S.; Menk, S. [Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany); and others

    2016-06-15

    An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm{sup −3} is derived, equivalent to a room-temperature pressure below 10{sup −14} mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

  17. The Rings of Saturn

    Science.gov (United States)

    Cuzzi, J. N.; Filacchione, G.; Marouf, E. A.

    2018-03-01

    One could become an expert on Saturn's iconic rings pretty easily in the early 1970s, as very little was known about them beyond the distinction between the A, B, and C rings, and the Cassini Division or "gap" between rings A and B (Alexander, 1962; Bobrov, 1970). Water ice was discovered spectroscopically on the ring particle surfaces, and radar and microwave emission observations proved that the particles must be centimeters to meters in size, consisting primarily, not just superficially, of water ice (Pollack, 1975). While a 2:1 orbital resonance with Mimas had long been suspected of having something to do with the Cassini Division, computers of the time were unable to model the subtle dynamical effects that we now know to dominate ring structure. This innocent state of affairs was exploded by the Voyager 1 and 2 encounters in 1980 and 1981. Spectacular images revealed filigree structure and odd regional color variations, and exquisitely detailed radial profiles of fluctuating particle abundance were obtained from the first stellar and radio occultations, having resolution almost at the scale of single particles. Voyager-era understanding was reviewed by Cuzzi et al. (1984) and Esposito et al. (1984). While the Voyager data kept ring scientists busy for decades, planning which led to the monumentally successful NASA-ESA-ASI Cassini mission, which arrived in 2004, had been under way even before Voyager got to Saturn. A review of pre-Cassini knowledge of Saturn's Rings can be found in Orton et al. (2009). This chapter will build on recent topical and process-specific reviews that treat the gamut of ring phenomena and its underlying physics in considerable detail (Colwell et al., 2009; Cuzzi et al., 2009; Horányi et al., 2009; Schmidt et al., 2009; Esposito, 2010; Tiscareno, 2013b; Esposito, 2014). We will follow and extend the general organization of Cuzzi et al. (2010), the most recent general discussion of Saturn's rings. For brevity and the benefit of the

  18. Compressible Vortex Ring

    Science.gov (United States)

    Elavarasan, Ramasamy; Arakeri, Jayawant; Krothapalli, Anjaneyulu

    1999-11-01

    The interaction of a high-speed vortex ring with a shock wave is one of the fundamental issues as it is a source of sound in supersonic jets. The complex flow field induced by the vortex alters the propagation of the shock wave greatly. In order to understand the process, a compressible vortex ring is studied in detail using Particle Image Velocimetry (PIV) and shadowgraphic techniques. The high-speed vortex ring is generated from a shock tube and the shock wave, which precedes the vortex, is reflected back by a plate and made to interact with the vortex. The shadowgraph images indicate that the reflected shock front is influenced by the non-uniform flow induced by the vortex and is decelerated while passing through the vortex. It appears that after the interaction the shock is "split" into two. The PIV measurements provided clear picture about the evolution of the vortex at different time interval. The centerline velocity traces show the maximum velocity to be around 350 m/s. The velocity field, unlike in incompressible rings, contains contributions from both the shock and the vortex ring. The velocity distribution across the vortex core, core diameter and circulation are also calculated from the PIV data.

  19. Interaction of Sound with Sound by Novel Mechanisms: Ultrasonic Four-Wave Mixing Mediated by a Suspension and Ultrasonic Three-Wave Mixing at a Free Surface

    Science.gov (United States)

    Simpson, Harry Jay

    Two mechanisms of sound interacting with sound are experimentally and theoretically investigated. Ultrasonic four-wave mixing in a dilute particle suspension, analogous to optical four-wave mixing in photorefractive materials, involves the interaction of three ultrasonic wavefields that produces a fourth scattered wavefield. The experimental configuration consists of two ultrasonic (800 kHz) pump waves that are used to produce a grating in a suspension of 25 μm diameter polymer particles in salt water. The pump waves are counter-propagating, which form a standing wavefield in the suspension and the less compressible particles are attracted to the pressure nodes in response to the time averaged radiation pressure. A higher frequency (2-10 MHz) ultrasonic wavefield is used to probe the resulting grating. The ultrasonic Bragg scattering is then measured. The scattering depends strongly on the response to the pump wave and is an unusual class of acoustical nonlinearity. Investigation of very small amplitude gratings are done by studying the temporal response of the Bragg scattering to a sudden turn on of a moderate amplitude pump wavefield in a previously homogeneous particle suspension. The Bragg scattering has been verified experimentally and is modeled for early-time grating formations using a sinusoidal grating. The larger amplitude gratings are studied in equilibrium and are modeled using an Epstein layer approximation. Ultrasonic three-wave mixing at a free surface involves the interaction of a high amplitude 400 kHz plane wavefield incident at 33^circ on a water-air interface with a normally incident high frequency (4.6 MHz) focused wavefield. The 400 kHz "pump" wavefield reflects from the surface and produces an oscillating surface displacement that forms a local traveling phase grating. Simultaneously the 4.6 MHz "probe" wavefield is reflected from the free surface. The grating scatters the focused probe wavefield and produces (or contributes to) spatially

  20. Ultrasonic superlensing jets and acoustic-fork sheets

    Energy Technology Data Exchange (ETDEWEB)

    Mitri, F.G., E-mail: F.G.Mitri@ieee.org

    2017-05-18

    Focusing acoustical (and optical) beams beyond the diffraction limit has remained a major challenge in imaging instruments and systems, until recent advances on “hyper” or “super” lensing and higher-resolution imaging techniques have shown the counterintuitive violation of this rule under certain circumstances. Nonetheless, the proposed technologies of super-resolution acoustical focusing beyond the diffraction barrier require complex tools such as artificially engineered metamaterials, and other hardware equipment that may not be easily synthesized or manufactured. The present contribution therefore suggests a simple and reliable method of using a sound-penetrable circular cylinder lens illuminated by a nonparaxial Gaussian acoustical sheet (i.e. finite beam in 2D) to produce non-evanescent ultrasonic superlensing jets (or bullets) and acoustical ‘snail-fork’ shaped wavefronts with limited diffraction. The generalized (near-field) scattering theory for acoustical sheets of arbitrary wavefronts and incidence is utilized to synthesize the incident beam based upon the angular spectrum decomposition method and the multipole expansion method in cylindrical wave functions to compute the scattered pressure around the cylinder with particular emphasis on its physical properties. The results show that depending on the beam and lens parameters, a tight focusing (with dimensions much smaller than the beam waist) can be achieved. Subwavelength resolution can be also achieved by selecting a lens material with a speed of sound exceeding that of the host fluid medium. The ultrasonic superlensing jets provide the impetus to develop improved subwavelength microscopy and acoustical image-slicing systems, cell lysis and surgery, and photoacoustic imaging to name a few examples. Moreover, an acoustical fork-sheet generation may open innovative avenues in reconfigurable on-chip micro/nanoparticle tweezers and surface acoustic waves devices. - Highlights: • Ultrasonic

  1. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions

    Directory of Open Access Journals (Sweden)

    Rymantas Kazys

    2015-08-01

    Full Text Available An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10−3 g/cm3 (1%.

  2. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions

    Science.gov (United States)

    Kazys, Rymantas; Sliteris, Reimondas; Rekuviene, Regina; Zukauskas, Egidijus; Mazeika, Liudas

    2015-01-01

    An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer) on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C) and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10−3 g/cm3 (1%). PMID:26262619

  3. Ultrasonic Technique for Density Measurement of Liquids in Extreme Conditions.

    Science.gov (United States)

    Kazys, Rymantas; Sliteris, Reimondas; Rekuviene, Regina; Zukauskas, Egidijus; Mazeika, Liudas

    2015-08-07

    An ultrasonic technique, invariant to temperature changes, for a density measurement of different liquids under in situ extreme conditions is presented. The influence of geometry and material parameters of the measurement system (transducer, waveguide, matching layer) on measurement accuracy and reliability is analyzed theoretically along with experimental results. The proposed method is based on measurement of the amplitude of the ultrasonic wave, reflected from the interface of the solid/liquid medium under investigation. In order to enhance sensitivity, the use of a quarter wavelength acoustic matching layer is proposed. Therefore, the sensitivity of the measurement system increases significantly. Density measurements quite often must be performed in extreme conditions at high temperature (up to 220 °C) and high pressure. In this case, metal waveguides between piezoelectric transducer and the measured liquid are used in order to protect the conventional transducer from the influence of high temperature and to avoid depolarization. The presented ultrasonic density measurement technique is suitable for density measurement in different materials, including liquids and polymer melts in extreme conditions. A new calibration algorithm was proposed. The metrological evaluation of the measurement method was performed. The expanded measurement uncertainty Uρ = 7.4 × 10(-3) g/cm(3) (1%).

  4. Steady reconstruction process - development, testing and comparison in ultrasonic testing

    International Nuclear Information System (INIS)

    Langenberg, K.J.; Schmitz, V.

    1986-01-01

    The fault parameters can be extracted from a few data of high quality in steady test procedures. The boundary conditions for the successful use of such a process were researched and found, so that by using theoretical models for the elasto-dynamic interaction of fault and ultrasonics, a concentration of wavefronts instead of resonances and a wide band careful collection of data makes a physical interpretation in the form of specific geometry torques possible. Models of the interaction of ultrasonics and faults for two fault geometries (cracks and pores) were developed which permit the calculation of A scans of any bandwidth and with any angle of scatter for the direct and mode converted parts of the elastic ultrasonic scatter wave. The curved pressure and shear waves including the mode converted bending fields over an angular range of 360deg were experimentally recorded. Their agreement including the additional wavefronts caused by the close field of the crack bending field is close. Classification of torques is done on two examples (crack, cylinder) for evaluation purposes. It was found that a classification was possible according to the sign of the a 1 polynomial coefficient. (orig./HP) [de

  5. Design of ultrasonic probe and evaluation of ultrasonic waves on E.coli in Sour Cherry Juice

    Directory of Open Access Journals (Sweden)

    B Hosseinzadeh Samani

    2015-09-01

    Full Text Available Introduction: The common method used for juice pasteurization is the thermal method since thermal methods contribute highly to inactivating microbes. However, applying high temperatures would lead to inefficient effects on nutrition and food value. Such effects may include vitamin loss, nutritional flavor loss, non-enzyme browning, and protein reshaping (Kuldiloke, 2002. In order to decrease the adverse effects of the thermal pasteurization method, other methods capable of inactivation of microorganisms can be applied. In doing so, non-thermal methods including pasteurization using high hydrostatic pressure processing (HPP, electrical fields, and ultrasound waves are of interest (Chen and Tseng, 1996. The reason for diminishing microbial count in the presence of ultrasonic waves could be due to the burst of very tiny bubbles developed by ultrasounds which expand quickly and burst in a short time. Due to this burst, special temperature and pressure conditions are developed which could initiate or intensify several physical and/or chemical reactions. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. Materials and methods: In order to supply uniform ultrasonic waves, a 1000 W electric generator (Model MPI, Switzerland working at 20±1 kHz frequency was used. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. For this purpose, a certain amount of sour cherry fruit was purchased from local markets. First, the fruits were washed, cleaned and cored. The prepared fruits were then dewatered using an electric juicer. In order to separate pulp suspensions and tissue components, the extracted juice was poured into a centrifuge with the speed of 6000 rpm for 20 min. For complete separation of the remaining suspended particles, the transparent portion of the extract was passed through a

  6. Plasma Surface Modification of Glass-Fibre-Reinforced Polyester Enhanced by Ultrasonic Irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Bardenshtein, Alexander

    2010-01-01

    treatment can be highly enhanced by simultaneous high-power ultrasonic irradiation of the treating surface, because the delivered acoustic energy can reduce the thickness of the boundary gas layer. Here surfaces of glass-fibre-reinforced polyester (GFRP) plates were treated using an atmospheric pressure...

  7. Use of Multidimensional Fiber Grating Strain Sensors for Damage Detection in Composite Pressure Vessels

    National Research Council Canada - National Science Library

    Kunzler, Marley

    2004-01-01

    ... during curing and pressure cycling near cut tow and Teflon tape defects. These changes in the multi-axis strain due to four pressure cycles and repeated impacts are measured and compared to ultrasonic and eddy current scans...

  8. Almost ring theory

    CERN Document Server

    2003-01-01

    This book develops thorough and complete foundations for the method of almost etale extensions, which is at the basis of Faltings' approach to p-adic Hodge theory. The central notion is that of an "almost ring". Almost rings are the commutative unitary monoids in a tensor category obtained as a quotient V-Mod/S of the category V-Mod of modules over a fixed ring V; the subcategory S consists of all modules annihilated by a fixed ideal m of V, satisfying certain natural conditions. The reader is assumed to be familiar with general categorical notions, some basic commutative algebra and some advanced homological algebra (derived categories, simplicial methods). Apart from these general prerequisites, the text is as self-contained as possible. One novel feature of the book - compared with Faltings' earlier treatment - is the systematic exploitation of the cotangent complex, especially for the study of deformations of almost algebras.

  9. Ultrasound periodic inspections of reactor pressure vessels

    International Nuclear Information System (INIS)

    Haniger, L.

    1980-01-01

    Two versions are described of ultrasonic equipment for periodic inspections of reactor pressure vessels. One uses the principle of exchangeable programmators with solid-state logic while the other uses programmable logic with semiconductor memories. The equipment is to be used for inspections of welded joints on the upper part of the V-1 reactor pressure vessel. (L.O.)

  10. Compact electron storage rings

    International Nuclear Information System (INIS)

    Williams, G.P.

    1987-01-01

    There have been many recent developments in the area of compact storage rings. Such rings would have critical wavelengths of typically 10 A, achieved with beam energies of several hundreds of MeV and superconducting dipole fields of around 5 Tesla. Although the primary motivation for progress in this area is that of commercial x-ray lithography, such sources might be an attractive source for college campuses to operate. They would be useful for many programs in materials science, solid state, x-ray microscopy and other biological areas. We discuss the properties of such sources and review developments around the world, primarily in the USA, japan and W. Germany

  11. The covariant chiral ring

    Energy Technology Data Exchange (ETDEWEB)

    Bourget, Antoine; Troost, Jan [Laboratoire de Physique Théorique, École Normale Supérieure, 24 rue Lhomond, 75005 Paris (France)

    2016-03-23

    We construct a covariant generating function for the spectrum of chiral primaries of symmetric orbifold conformal field theories with N=(4,4) supersymmetry in two dimensions. For seed target spaces K3 and T{sup 4}, the generating functions capture the SO(21) and SO(5) representation theoretic content of the chiral ring respectively. Via string dualities, we relate the transformation properties of the chiral ring under these isometries of the moduli space to the Lorentz covariance of perturbative string partition functions in flat space.

  12. Vortex and source rings

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    2017-01-01

    The velocity field, vector potential and velocity gradient of a vortex ring is derived in this chapter. The Biot-Savart law for the vector potential and velocity is expressed in a first section. Then, the flow is derived at specific locations: on the axis, near the axis and in the far field where...... the analogy to a doublet field is made. The following section derive the value of the vector potential and velocity field in the full domain. The expression for the velocity gradient is also provided since it may be relevant in a simulation with vortex particles and vortex rings. Most of this chapter...

  13. The Saturnian rings

    International Nuclear Information System (INIS)

    Alfven, H.

    1975-09-01

    The structure of the Saturnian rings is traditionally believed to be due to resonances caused by Mimas (and possibly other satellites). It is shown that both theoretical and observational evidence rule out this interpretation. The increased observational accuracy on one hand and the increased understanding of the cosmogonic processes on the other makes it possible to explain the structure of the ring system as a product of condensation from a partially corotating plasma. In certain respects the agreement between theory and observations is about 1%. (Auth.)

  14. RINGED ACCRETION DISKS: INSTABILITIES

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, D.; Stuchlík, Z., E-mail: d.pugliese.physics@gmail.com, E-mail: zdenek.stuchlik@physics.cz [Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Faculty of Philosophy and Science, Silesian University in Opava, Bezručovo náměstí 13, CZ-74601 Opava (Czech Republic)

    2016-04-01

    We analyze the possibility that several instability points may be formed, due to the Paczyński mechanism of violation of mechanical equilibrium, in the orbiting matter around a supermassive Kerr black hole. We consider a recently proposed model of a ringed accretion disk, made up by several tori (rings) that can be corotating or counter-rotating relative to the Kerr attractor due to the history of the accretion process. Each torus is governed by the general relativistic hydrodynamic Boyer condition of equilibrium configurations of rotating perfect fluids. We prove that the number of the instability points is generally limited and depends on the dimensionless spin of the rotating attractor.

  15. Effects of ultrasonic instrumentation on enamel surfaces with various defects.

    Science.gov (United States)

    Kim, S-Y; Kang, M-K; Kang, S-M; Kim, H-E

    2018-05-01

    The aim of this study was to analyse the enamel damage caused by ultrasonic scaling of teeth with various enamel conditions that are difficult to identify by visual inspection, such as enamel cracks, early caries and resin restorations. In total, 120 tooth surfaces were divided into 4 experimental groups using a quantitative light-induced fluorescence-digital system: sound enamel group, enamel cracks group, early caries group and resin restoration group. A skilled dental hygienist performed ultrasonic scaling under a standardized set of conditions: a ≤ 15° angle between the scaler tip and tooth surface and 40-80 g of lateral pressure at the rate of 12 times/10 s. Following scaling, the depth of enamel damage was measured using a surface profilometer and observed using scanning electron microscopy (SEM). The damage depth was the greatest in the enamel cracks group (37.63 ± 34.42 μm), followed by the early caries group (26.81 ± 8.67 μm), resin restoration group (19.63 ± 6.73 μm) and the sound enamel group (17.00 ± 5.66 μm). The damage depth was significantly deeper in the enamel cracks and early caries groups than in the sound enamel group (P enamel loss in the enamel cracks, early caries and resin restoration groups. The results of this study suggest that ultrasonic scaling can cause further damage to teeth with enamel cracks, early caries and resin restorations. Therefore, accurate identification of tooth conditions and calculus before the initiation of ultrasonic scaling is necessary to minimize damage. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Ultrasonic examination of defects close to the outer surface

    International Nuclear Information System (INIS)

    Benoist, P.; Serre, M.; Champigny, F.

    1986-11-01

    During the examination of a pressurized water reactor vessel with an in Service Inspection Machine (MIS), various welds are scanned with immersion ultrasonic focused transducers from the inside of the vessel. Defects close to the outer surface are sometimes detected, and sizing with the successive 6 dB drop method leads to oversize some indications; this is caused by various reflections on the outer wall; the corner echo is of particular importance here. CEA and EDF have started an experimental program in order to study the response of volumetric and planar defects located near the outer surface. We present here the first results obtained with artificial defects. 2 refs

  17. Track formation in a liquid hydrogen ultrasonic bubble chamber

    CERN Document Server

    Brown, R C A; Jarman, P D

    1973-01-01

    Track sensitivity to minimum ionising particles has been demonstrated in liquid hydrogen using only an intense ultrasonic field. Carefully designed transducer systems are shown to be capable of producing pressure amplitudes >2.8 atm in a standing wave system in liquid hydrogen. The growth of bubbles to visible size (0.1 mm) in less than 0.2 ms, and their collapse in less than 15 ms, indicates that rapid cycling rates of 50-100 pulses per second may be feasible with this technique. (11 refs).

  18. Ultrasonic Abrasive Removal Of EDM Recast

    Science.gov (United States)

    Mandel, Johnny L.; Jacobson, Marlowe S.

    1990-01-01

    Ultrasonic abrasive process removes layer of recast material generated during electrical-discharge machining (EDM) of damper pocket on turbine blade. Form-fitted tool vibrated ultrasonically in damper pocket from which material removed. Vibrations activate abrasive in pocket. Amount of material removed controlled precisely.

  19. Defect detection and sizing in ultrasonic imaging

    International Nuclear Information System (INIS)

    Moysan, J.; Benoist, P.; Chapuis, N.; Magnin, I.

    1991-01-01

    This paper introduces imaging processing developed with the SPARTACUS system in the field of ultrasonic testing. The aim of the imaging processing is to detect and to separate defects echoes from background noise. Image segmentation and particularities of ultrasonic images are the base of studied methods. 4 figs.; 6 refs [fr

  20. Reproducibility of the results in ultrasonic testing

    International Nuclear Information System (INIS)

    Chalaye, M.; Launay, J.P.; Thomas, A.

    1980-12-01

    This memorandum reports on the conclusions of the tests carried out in order to evaluate the reproducibility of ultrasonic tests made on welded joints. FRAMATOME have started a study to assess the dispersion of results afforded by the test line and to characterize its behaviour. The tests covered sensors and ultrasonic generators said to be identical to each other (same commercial batch) [fr

  1. Backward ray tracing for ultrasonic imaging

    NARCIS (Netherlands)

    Breeuwer, R.

    1990-01-01

    Focused ultrasonic beams frequently pass one or more media interfaces, strongly affecting the ultrasonic beamshape and focusing. A computer program, based on backward ray tracing was developed to compute the shape of a corrected focusing mirror. This shape is verified with another program; then the

  2. Beat-Frequency/Microsphere Medical Ultrasonic Imaging

    Science.gov (United States)

    Yost, William T.; Cantrell, John H.; Pretlow, Robert A., III

    1995-01-01

    Medical ultrasonic imaging system designed to provide quantitative data on various flows of blood in chambers, blood vessels, muscles, and tissues of heart. Sensitive enough to yield readings on flows of blood in heart even when microspheres used as ultrasonic contrast agents injected far from heart and diluted by circulation of blood elsewhere in body.

  3. Fusion rings and fusion ideals

    DEFF Research Database (Denmark)

    Andersen, Troels Bak

    by the so-called fusion ideals. The fusion rings of Wess-Zumino-Witten models have been widely studied and are well understood in terms of precise combinatorial descriptions and explicit generating sets of the fusion ideals. They also appear in another, more general, setting via tilting modules for quantum......This dissertation investigates fusion rings, which are Grothendieck groups of rigid, monoidal, semisimple, abelian categories. Special interest is in rational fusion rings, i.e., fusion rings which admit a finite basis, for as commutative rings they may be presented as quotients of polynomial rings...

  4. Sector ring accelerator ''RESATRON''

    International Nuclear Information System (INIS)

    Schwabe, E.

    1980-01-01

    Project of sector ring accelerator RESATRON is described. The curiosity of this accelerator is the second cycle of acceleration of the beam after stripping it on the foil. In such an accelerator heavy ions with a different ratio Z to A can be accelerated. (S.B.)

  5. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation...

  6. SXLS storage ring design

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    X-ray lithography has emerged as a strong candidate to meet the demands of ever finer linewidths on integrated circuits, particularly for linewidths less than .25 microns. Proximity printing X-ray lithography makes use of soft X-rays to shadow print an image of a mask onto a semiconductor wafer to produce integrated circuits. To generate the required X-rays in sufficient quantities to make commercial production viable, electron storage rings have been proposed as the soft X-ray sources. Existing storage rings have been used to do the initial development work and the success of these efforts has led the lithographers to request that new rings be constructed that are dedicated to X-ray lithography. As a result of a series of workshops held at BNL [10.3] which were attended by both semiconductor and accelerator scientists, the following set of zeroth order specifications' on the light and electron beam of a storage ring for X-ray lithography were developed: critical wavelength of light: λ c = 6 to 10 angstroms, white light power: P = 0.25 to 2.5 watts/mrad, horizontal collection angle per port: θ = 10 to 50 mrad, electron beam sizes: σ x ∼ σ y y ' < 1 mrad

  7. Ring magnetron ionizer

    International Nuclear Information System (INIS)

    Alessi, J.G.

    1986-01-01

    A ring magnetron D - charge exchange ionizer has been built and tested. An H - current of 500 μA was extracted with an estimated H 0 density in the ionizer of 10 12 cm -3 . This exceeds the performance of ionizers presently in use on polarized H - sources. The ionizer will soon be tested with a polarized atomic beam

  8. Algebras, rings and modules

    CERN Document Server

    Hazewinkel, Michiel; Kirichenko, V V

    Provides both the classical aspects of the theory of groups and their representations as well as a general introduction to the modern theory of representations, including the representations of quivers and finite partially ordered sets. This volume provides the theory of semiprime Noetherian semiperfect and semidistributive rings.

  9. Lattices for antiproton rings

    International Nuclear Information System (INIS)

    Autin, B.

    1984-01-01

    After a description of the constraints imposed by the cooling of Antiprotons on the lattice of the rings, the reasons which motivate the shape and the structure of these machines are surveyed. Linear and non-linear beam optics properties are treated with a special amplification to the Antiproton Accumulator. (orig.)

  10. The Dynamic Performance of Flexural Ultrasonic Transducers

    Directory of Open Access Journals (Sweden)

    Andrew Feeney

    2018-01-01

    Full Text Available Flexural ultrasonic transducers are principally used as proximity sensors and for industrial metrology. Their operation relies on a piezoelectric ceramic to generate a flexing of a metallic membrane, which delivers the ultrasound signal. The performance of flexural ultrasonic transducers has been largely limited to excitation through a short voltage burst signal at a designated mechanical resonance frequency. However, a steady-state amplitude response is not generated instantaneously in a flexural ultrasonic transducer from a drive excitation signal, and differences in the drive characteristics between transmitting and receiving transducers can affect the measured response. This research investigates the dynamic performance of flexural ultrasonic transducers using acoustic microphone measurements and laser Doppler vibrometry, supported by a detailed mechanical analog model, in a process which has not before been applied to the flexural ultrasonic transducer. These techniques are employed to gain insights into the physics of their vibration behaviour, vital for the optimisation of industrial ultrasound systems.

  11. Eddy current and ultrasonic fuel channel inspection at Karachi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Mayo, W.R.; Alam, M.M.

    1997-01-01

    In November of 1993 and in-service inspection was performed on eight fuel channels in the Karachi Nuclear Power Plant (KANUPP) reactor. The workscope included ultrasonic and eddy current volumetric examinations, and eddy current measurement of pressure-to calandria tube gap. This paper briefly discusses the planning strategy of the ultrasonic and eddy current examinations, and describes the equipment developed to meet the requirements, followed by details of the actual channel inspection campaign. The presented nondestructive examinations assisted in determining fitness for service of KANUPP reactor channels in general, and confirmed that the problems associated with channel G12 were not generic in nature. (author)

  12. Proceedings of a specialist meeting on the ultrasonic inspection of reactor components

    International Nuclear Information System (INIS)

    1976-01-01

    Beside synthesis of two conferences on nondestructive testing and on inspection, the contributions of this conference are reporting experimental observations and research works on ultrasonic techniques, methods, procedures (pre-service or in-service) and equipment for the inspection of nuclear reactor components (pressure vessels, tubing and piping), generally in stainless steel (often austenitic or ferritic) material or in zirconium alloy. Some contributions are also dealing with the relationship between material microstructure and ultrasonic inspection method and equipment, or with the detection and sizing precision of flaws (cracks)

  13. Whole-body ring-shaped confocal photoacoustic computed tomography of small animals in vivo

    Science.gov (United States)

    Xia, Jun; Chatni, Muhammad R.; Maslov, Konstantin; Guo, Zijian; Wang, Kun; Anastasio, Mark; Wang, Lihong V.

    2012-05-01

    We report a novel small-animal whole-body imaging system called ring-shaped confocal photoacoustic computed tomography (RC-PACT). RC-PACT is based on a confocal design of free-space ring-shaped light illumination and 512-element full-ring ultrasonic array signal detection. The free-space light illumination maximizes the light delivery efficiency, and the full-ring signal detection ensures a full two-dimensional view aperture for accurate image reconstruction. Using cylindrically focused array elements, RC-PACT can image a thin cross section with 0.10 to 0.25 mm in-plane resolutions and 1.6 s/frame acquisition time. By translating the mouse along the elevational direction, RC-PACT provides a series of cross-sectional images of the brain, liver, kidneys, and bladder.

  14. Plasma Sterilizer with Ultrasonic Cavitation

    International Nuclear Information System (INIS)

    Krasnyj, V.V.; Klosovsky, A.V.; Panasko, T.A.; Shvets, O.M.; Semenova, O.T.; Taran, V.S.; Tereshin, V.I.

    2006-01-01

    A sterilizer consists of ozone generator based on a barrier glow discharge with the flat electrodes covered with dielectric with a high-voltage pulsed power supply of up to 250 W (1). The sterilization camera is equipped with ultrasonic source with the power of 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. Ozone concentration in the aqueous solution was 6 mg/liter with ozone concentration at the output of ozone generator 30 mg/liter. The complete inactivation of spores took 15 min

  15. Propellers in Saturn's rings

    Science.gov (United States)

    Sremcevic, M.; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2013-12-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings. Even if the objects are too small to be directly observed, each creates a much larger gravitational imprint on the surrounding ring material. These strongly depend on the mass of the object and range from "S" like propeller-shaped structures for about 100m-sized icy bodies to the opening of circumferential gaps as in the case of the embedded moons Pan and Daphnis and their corresponding Encke and Keeler Gaps. Since the beginning of the Cassini mission many of these smaller objects (~data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We show evidence that B ring seems to harbor two distinct populations of propellers: "big" propellers covering tens of degrees in azimuth situated in the densest part of B ring, and "small" propellers in less dense inner B ring that are similar in size and shape to known A ring propellers. The population of "big" propellers is exemplified with a single object which is observed for 5 years of Cassini data. The object is seen as a very elongated bright stripe (40 degrees wide) in unlit Cassini images, and dark stripe in lit geometries. In total we report observing the feature in images at 18 different epochs between 2005 and 2010. In UVIS occultations we observe this feature as an optical depth depletion in 14 out of 93 occultation cuts at corrotating longitudes compatible with imaging data. Combining the available Cassini data we infer that the object is a partial gap located at r=112,921km embedded in the high optical depth region of the B ring. The gap moves at Kepler speed appropriate for its radial location. Radial offsets of the gap locations in UVIS occultations are consistent with an asymmetric propeller shape. The asymmetry of the observed shape is most likely a consequence of the strong surface mass density gradient, as the feature is located at an edge between

  16. Initial evaluation of ultrasonic attenuation measurements for estimating fracture toughness of RPV steels

    Energy Technology Data Exchange (ETDEWEB)

    Hiser, A.L. Jr.; Green, R.E. Jr. [Johns Hopkins Univ., Baltimore, MD (United States). Center for Nondestructive Evaluation

    1999-08-01

    Neutron bombardment of reactor pressure vessel (RPV) steels causes reductions in fracture toughness in these steels, termed neutron irradiation embrittlement. Currently, there are no accepted methods for nondestructive determination of the extent of the irradiation embrittlement nor the actual fracture toughness of the reactor pressure vessel. This paper provides initial results of an effort addressing the use of ultrasonic attenuation as a suitable parameter for nondestructive determination of irradiation embrittlement in RPV steels. (orig.)

  17. A New Low-frequency Sonophoresis System Combined with Ultrasonic Motor and Transducer

    Science.gov (United States)

    Zhu, Pancheng; Peng, Hanmin; Yang, Jianzhi; Mao, Ting; Sheng, Juan

    2018-03-01

    Low frequency sonophoresis (LFS) is currently being attempted as a transdermal drug delivery method in clinical areas. However, it lacks both an effective control method and the equipment to satisfy the varying drug dosage requirements of individual patients. Herein, a novel method aimed at controlling permeability is proposed and developed, using a pressure control strategy which is based on an accurate, adjustable and non-invasive ultrasound transdermal drug delivery system in in vitro LFS. The system mainly consists of a lead screw linear ultrasonic motor and an ultrasonic transducer, in which the former offers pressure and the latter provides ultrasound wave in the liquid. The ultrasound can enhance non-invasive permeation and the pressure from the motor can control the permeability. The calculated and experimental results demonstrate that the maximum pressure on artificial skin is under the area with the maximum vibration amplitude of the ultrasonic transducer, and the total pressure consists of acoustic pressure from the transducer and approximate static pressure from the motor. Changing the static pressure from the ultrasonic motor can effectively control the non-invasive permeability, by adjusting the duty ratio or the amplitude of the motor’s driving voltage. In addition, the permeability control of calcein by thrust control is realized in 15 min, indicating the suitability of this method for application in accurate medical technology. The obtained results reveal that the issue of difficult permeability control can be addressed, using this control method in in vitro LFS to open up a route to the design of accurate drug delivery technology for individual patients.

  18. Ultrasonic imaging of projected components of PFBR

    Energy Technology Data Exchange (ETDEWEB)

    Sylvia, J.I., E-mail: sylvia@igcar.gov.in [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India); Jeyan, M.R.; Anbucheliyan, M.; Asokane, C.; Babu, V. Rajan; Babu, B.; Rajan, K.K.; Velusamy, K.; Jayakumar, T. [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, Tamil Nadu (India)

    2013-05-15

    Highlights: ► Under sodium ultrasonic scanner in PFBR is for detecting protruding objects. ► Feasibility study for detecting Absorber rods and its drive mechanisms. ► Developed in-house PC based ultrasonic imaging system. ► Different case studies were carried out on simulated ARDM's. ► Implemented the experimental results to PFBR application. -- Abstract: The 500 MWe, sodium cooled, Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam in India. Opacity of sodium restricts visual inspection of components immersed in sodium by optical means. Ultrasonic wave passes through sodium hence ultrasonic techniques using under sodium ultrasonic scanners are developed to obtain under sodium images. The main objective of such an Under Sodium Ultrasonic Scanner (USUSS) for Prototype Fast Breeder Reactor (PFBR) is to detect and ensure that no core Sub Assembly (SA) or Absorber Rod or its Drive Mechanism is protruded in the above core plenum before starting the fuel handling operation. Hence, it is necessary to detect and locate the object, if it is protruding the above core plenum. To study the feasibility of detecting the absorber rods and their drive mechanisms using direct ultrasonic imaging technique, experiments were carried out for different orientations and profiles of the projected components in a 5 m diameter water tank. The in-house developed PC based ultrasonic scanning system is used for acquisition and analysis of data. The pseudo three dimensional color images obtained are discussed and the results are applicable for PFBR. This paper gives the details of the features of the absorber rods and their drive mechanisms, their orientation in the reactor core, experimental setup, PC based ultrasonic scanning system, ultrasonic images and the discussion on the results.

  19. FUZZY RINGS AND ITS PROPERTIES

    Directory of Open Access Journals (Sweden)

    Karyati Karyati

    2017-01-01

      One of algebraic structure that involves a binary operation is a group that is defined  an un empty set (classical with an associative binary operation, it has identity elements and each element has an inverse. In the structure of the group known as the term subgroup, normal subgroup, subgroup and factor group homomorphism and its properties. Classical algebraic structure is developed to algebraic structure fuzzy by the researchers as an example semi group fuzzy and fuzzy group after fuzzy sets is introduced by L. A. Zadeh at 1965. It is inspired of writing about semi group fuzzy and group of fuzzy, a research on the algebraic structure of the ring is held with reviewing ring fuzzy, ideal ring fuzzy, homomorphism ring fuzzy and quotient ring fuzzy with its properties. The results of this study are obtained fuzzy properties of the ring, ring ideal properties fuzzy, properties of fuzzy ring homomorphism and properties of fuzzy quotient ring by utilizing a subset of a subset level  and strong level  as well as image and pre-image homomorphism fuzzy ring.   Keywords: fuzzy ring, subset level, homomorphism fuzzy ring, fuzzy quotient ring

  20. 21 CFR 882.1925 - Ultrasonic scanner calibration test block.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic scanner calibration test block. 882... Ultrasonic scanner calibration test block. (a) Identification. An ultrasonic scanner calibration test block is a block of material with known properties used to calibrate ultrasonic scanning devices (e.g., the...

  1. Experiments on Ultrasonic Lubrication Using a Piezoelectrically-assisted Tribometer and Optical Profilometer.

    Science.gov (United States)

    Dong, Sheng; Dapino, Marcelo

    2015-09-28

    Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at a frequency above the acoustic range (20 kHz). As a solid-state technology, ultrasonic lubrication can be used where conventional lubricants are unfeasible or undesirable. Further, ultrasonic lubrication allows for electrical modulation of the effective friction coefficient between two sliding surfaces. This property enables adaptive systems that modify their frictional state and associated dynamic response as the operating conditions change. Surface wear can also be reduced through ultrasonic lubrication. We developed a protocol to investigate the dependence of friction force reduction and wear reduction on the linear sliding velocity between ultrasonically lubricated surfaces. A pin-on-disc tribometer was built which differs from commercial units in that a piezoelectric stack is used to vibrate the pin at 22 kHz normal to the rotating disc surface. Friction and wear metrics including effective friction force, volume loss, and surface roughness are measured without and with ultrasonic vibrations at a constant pressure of 1 to 4 MPa and three different sliding velocities: 20.3, 40.6, and 87 mm/sec. An optical profilometer is utilized to characterize the wear surfaces. The effective friction force is reduced by 62% at 20.3 mm/sec. Consistently with existing theories for ultrasonic lubrication, the percent reduction in friction force diminishes with increasing speed, down to 29% friction force reduction at 87 mm/sec. Wear reduction remains essentially constant (49%) at the three speeds considered.

  2. Inorganic glass ceramic slip rings

    Science.gov (United States)

    Glossbrenner, E. W.; Cole, S. R.

    1972-01-01

    Prototypes of slip rings have been fabricated from ceramic glass, a material which is highly resistant to deterioration due to high temperature. Slip ring assemblies were not structurally damaged by mechanical tests and performed statisfactorily for 200 hours.

  3. Uniquely Strongly Clean Group Rings

    Institute of Scientific and Technical Information of China (English)

    WANG XIU-LAN

    2012-01-01

    A ring R is called clean if every element is the sum of an idempotent and a unit,and R is called uniquely strongly clean (USC for short) if every element is uniquely the sum of an idempotent and a unit that commute.In this article,some conditions on a ring R and a group G such that RG is clean are given.It is also shown that if G is a locally finite group,then the group ring RG is USC if and only if R is USC,and G is a 2-group.The left uniquely exchange group ring,as a middle ring of the uniquely clean ring and the USC ring,does not possess this property,and so does the uniquely exchange group ring.

  4. Ultrasonic relaxations in borate glasses

    International Nuclear Information System (INIS)

    D'Angelo, G.; Tripodo, G.; Carini, G.; Cosio, E.; Bartolotta, A.; Di Marco, G.

    2004-01-01

    The attenuation and velocity of ultrasonic waves of frequencies in the range from 10 to 70 MHz have been measured in M 2 O-B 2 O 3 borate glasses (M: Li or Ag) as a function of temperature between 15 and 350 K. The velocity of sound waves decreases with increasing temperature in all the glasses, the decrease as the temperature is increased is larger in glasses containing silver than in those with lithium. A broad relaxation peak characterises the attenuation behaviour of the lithium and silver borate glasses at temperatures below 100 K and is paralleled by a corresponding dispersive behaviour of the sound velocity. Above 100 K, the ultrasonic velocity shows a nearly linear behaviour regulated by the vibrational anharmonicity, which decreases with increasing content of modifier oxide and is smaller in lithium than in silver borates. These results suggest that the relaxation of structural defects and the anharmonicity of borate glasses are strongly affected by two parameters: the number of bridging bonds per network forming ion and the polarising power of network modifier ions which occupy sites in the existing interstices

  5. Deconvolution algorithms applied in ultrasonics

    International Nuclear Information System (INIS)

    Perrot, P.

    1993-12-01

    In a complete system of acquisition and processing of ultrasonic signals, it is often necessary at one stage to use some processing tools to get rid of the influence of the different elements of that system. By that means, the final quality of the signals in terms of resolution is improved. There are two main characteristics of ultrasonic signals which make this task difficult. Firstly, the signals generated by transducers are very often non-minimum phase. The classical deconvolution algorithms are unable to deal with such characteristics. Secondly, depending on the medium, the shape of the propagating pulse is evolving. The spatial invariance assumption often used in classical deconvolution algorithms is rarely valid. Many classical algorithms, parametric and non-parametric, have been investigated: the Wiener-type, the adaptive predictive techniques, the Oldenburg technique in the frequency domain, the minimum variance deconvolution. All the algorithms have been firstly tested on simulated data. One specific experimental set-up has also been analysed. Simulated and real data has been produced. This set-up demonstrated the interest in applying deconvolution, in terms of the achieved resolution. (author). 32 figs., 29 refs

  6. Ultrasonic Characterization of Aerospace Composites

    Science.gov (United States)

    Leckey, Cara; Johnston, Patrick; Haldren, Harold; Perey, Daniel

    2015-01-01

    Composite materials have seen an increased use in aerospace in recent years and it is expected that this trend will continue due to the benefits of reduced weight, increased strength, and other factors. Ongoing work at NASA involves the investigation of the large-scale use of composites for spacecraft structures (SLS components, Orion Composite Crew Module, etc). NASA is also involved in work to enable the use of composites in advanced aircraft structures through the Advanced Composites Project (ACP). In both areas (space and aeronautics) there is a need for new nondestructive evaluation and materials characterization techniques that are appropriate for characterizing composite materials. This paper will present an overview of NASA's needs for characterizing aerospace composites, including a description of planned and ongoing work under ACP for the detection of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking. The research approaches include investigation of angle array, guided wave, and phase sensitive ultrasonic methods. The use of ultrasonic simulation tools for optimizing and developing methods will also be discussed.

  7. Ultrasonic inspection of inpile tubes

    International Nuclear Information System (INIS)

    Boyd, D.M.; Bossi, H.

    1985-01-01

    The in-service inspection (ISI) of inpile tubes can be performed accurately and safely with a semiautomatic ultrasonic inspection system. The ultrasonic technique uses a set of multiple transducers to detect and size cracks, voids, and laminations radially and circumferentially. Welds are also inspected for defects. The system is designed to inspect stainless steel and Inconel tubes ranging from 53.8 mm (2.12 in.) to 101.6 mm (4 in.) inner diameter with wall thickness on the order of 5 mm. The inspection head contains seven transducers mounted in a surface-following device. Six angle-beam transducers generate shear waves in the tubes. Two of the six are oriented to detect circumferential cracks, and two detect axial cracks. Although each of these four transducers is used in the pulse-echo mode, they are oriented in aligned sets so pitch-catch operation is possible if desired. The remaining angle-beam transducers are angulated to detect flaws that are off axial or circumferential orientation. The seventh transducer is used for longitudinal inspection and detects and sizes laminar-type defects

  8. Reproduction of mouse-pup ultrasonic vocalizations by nanocrystalline silicon thermoacoustic emitter

    Science.gov (United States)

    Kihara, Takashi; Harada, Toshihiro; Kato, Masahiro; Nakano, Kiyoshi; Murakami, Osamu; Kikusui, Takefumi; Koshida, Nobuyoshi

    2006-01-01

    As one of the functional properties of ultrasound generator based on efficient thermal transfer at the nanocrystalline silicon (nc-Si) layer surface, its potential as an ultrasonic simulator of vocalization signals is demonstrated by using the acoustic data of mouse-pup calls. The device composed of a surface-heating thin-film electrode, an nc-Si layer, and a single-crystalline silicon (c-Si) wafer, exhibits an almost completely flat frequency response over a wide range without any mechanical surface vibration systems. It is shown that the fabricated emitter can reproduce digitally recorded ultrasonic mouse-pups vocalizations very accurately in terms of the call duration, frequency dispersion, and sound pressure level. The thermoacoustic nc-Si device provides a powerful physical means for the understanding of ultrasonic communication mechanisms in various living animals.

  9. The Ring Current Response to Solar and Interplanetary Storm Drivers

    Science.gov (United States)

    Mouikis, C.; Kistler, L. M.; Bingham, S.; Kronberg, E. A.; Gkioulidou, M.; Huang, C. L.; Farrugia, C. J.

    2014-12-01

    The ring current responds differently to the different solar and interplanetary storm drivers such as coronal mass injections, (CME's), corotating interaction regions (CIR's), high-speed streamers and other structures. The resulting changes in the ring current particle pressure, in turn, change the global magnetic field, controlling the transport of the radiation belts. To quantitatively determine the field changes during a storm throughout the magnetosphere, it is necessary to understand the transport, sources and losses of the particles that contribute to the ring current. Because the measured ring current energy spectra depend not only on local processes, but also on the history of the ions along their entire drift path, measurements of ring current energy spectra at two or more locations can be used to strongly constrain the time dependent magnetic and electric fields. In this study we use data predominantly from the Cluster and the Van Allen Probes, covering more than a full solar cycle (from 2001 to 2014). For the period 2001-2012, the Cluster CODIF and RAPID measurements of the inner magnetosphere are the primary data set used to monitor the storm time ring current variability. After 2012, the Cluster data set complements the data from the Van Allen Probes HOPE and RBSPICE instruments, providing additional measurements from different MLT and L shells. Selected storms from this periods, allow us to study the ring current dynamics and pressure changes, as a function of L shell, magnetic local time, and the type of interplanetary disturbances.

  10. Design and development of an ultrasonic pulser-receiver unit for non-destructive testing of materials

    International Nuclear Information System (INIS)

    Patankar, V.H.; Joshi, V.M.

    2002-11-01

    The pulser/receiver constitutes the most vital part of an ultrasonic flaw detector or an ultrasonic imaging system used for inspection of materials. The ultrasonic properties of the material and resolution requirements govern the choice of the frequency of ultrasound that can be optimally used. The pulser/receiver in turn decides the efficiency of excitation of the transducer and the overall signal to noise ratio of the system for best sensitivity and resolution. A variety of pulsers are used in the ultrasonic instruments employed for materials inspection. This report describes a square wave type of an ultrasonic pulser-receiver unit developed at Ultrasonic Instrumentation Section, Electronics Division, BARC. It has been primarily designed for excitation of the transducer that is used with a multi-channel ultrasonic imaging system ULTIMA 100M targeted for inspection of SS403 billets, which are in turn used as the base material for fabrication of end fittings for coolant channels of pressurized heavy water nuclear reactors (PHWRs). The design of the pulser is based upon very fast MOSFETs, configured as electronic switches. The pulser is operated with a linear bipolar H.V. supply (+/- 500V max.). The receiver provides a 60 dB gain with a -3 dB BW of 40 MHz. This pulser/receiver unit has been successfully interfaced with a 4 channel ULTIMA 100 M4 multichannel ultrasonic C-scan imaging system, also designed and developed by the authors at Ultrasonic Instrumentation Section (Electronics Division, BARC) and supplied to Centre for Design and Manufacturer - CDM, BARC. This system is being regularly used in C-scan imaging mode for volumetric inspection of SS403 billets for end fittings of 500 MWe PHWRs. (author)

  11. A new approach involving a multi transducer ultrasonic system for cleaning turbine engines' oil filters under practical conditions.

    Science.gov (United States)

    Nguyen, Dinh Duc; Ngo, Huu Hao; Yoon, Yong Soo; Chang, Soon Woong; Bui, Hong Ha

    2016-09-01

    The purpose of this paper is to provide a green technology that can clean turbine engine oil filters effectively in ships using ultrasound, with ultrasonic devices having a frequency of 25kHz and different powers of 300W and 600W, respectively. The effects of temperature, ultrasonic cleaning times, pressure losses through the oil filter, solvent washing, and ultrasonic power devices were investigated. In addition, the cleaning efficiency of three modes (hand washing, preliminary washing and ultrasonic washing) were compared to assess their relative effectiveness. Experimental results revealed that the necessary ultrasonic time varied significantly depending on which solvent was used for washing. For instance, the optimum ultrasonic cleaning time was 50-60min when the oil filter was cleaned in a solvent of kerosene oil (KO) and over 80min when in a solvent of diesel oil (DO) using the same ultrasonic generator device (25kHz, 600W) and experimental conditions. Furthermore, microscopic examination did not reveal any damage or breakdown on or within the structure of the filter after ultrasonic cleaning, even in the filter's surfaces at a constantly low frequency of 25kHz and power specific capacity (100W/gal). Overall, it may be concluded that ultrasound-assisted oil filter washing is effective, requiring a significantly shorter time than manual washing. This ultrasonic method also shows promise as a green technology for washing oil filters in turbine engines in general and Vietnamese navy ships in particular, because of its high cleaning efficiency, operational simplicity and savings. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Ring closure in actin polymers

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Supurna, E-mail: supurna@rri.res.in [Raman Research Institute, Bangalore 560080 (India); Chattopadhyay, Sebanti [Doon University, Dehradun 248001 (India)

    2017-03-18

    We present an analysis for the ring closure probability of semiflexible polymers within the pure bend Worm Like Chain (WLC) model. The ring closure probability predicted from our analysis can be tested against fluorescent actin cyclization experiments. We also discuss the effect of ring closure on bend angle fluctuations in actin polymers. - Highlights: • Ring closure of biopolymers. • Worm like chain model. • Predictions for experiments.

  13. Simulation and Optimization of Contactless Power Transfer System for Rotary Ultrasonic Machining

    Directory of Open Access Journals (Sweden)

    Wang Xinwei

    2016-01-01

    Full Text Available In today’s rotary ultrasonic machining (RUM, the power transfer system is based on a contactless power system (rotary transformer rather than the slip ring that cannot cope with high-speed rotary of the tool. The efficiency of the rotary transformer is vital to the whole rotary ultrasonic machine. This paper focused on simulation of the rotary transformer and enhancing the efficiency of the rotary transformer by optimizing three main factors that influence its efficiency, including the gap between the two ferrite cores, the ratio of length and width of the ferrite core and the thickness of ferrite. The finite element model of rotary transformer was built on Maxwell platform. Simulation and optimization work was based on the finite element model. The optimization results compared with the initial simulation result showed an approximate 18% enhancement in terms of efficiency, from 77.69% to 95.2%.

  14. Design of low energy ring(s)

    CERN Document Server

    Lachaize, Antoine

    During the last two years, several upgrades of the initial baseline scenario were studied with the aim of increasing the average intensity of ion beams in the accelerator chain of the Beta Beam complex. This is the reason why the Rapid Cycling Synchrotron (RCS) specifications were reconsidered many times [1], [2], [3].General considerations on the optical design were presented at the Beta Beam Task Meetings held at CERN and at Saclay in 2005 [4]. More detailed beam optics studies were performed during the next months. Lattices, RF system parameters, multi-turn injection scheme, fast extraction, closed orbit correction and chromaticity correction systems were proposed for different versions of the RCS [5], [6], [7].Finally, the RCS specifications have stabilized in November 2006 after the fourth Beta Beam Task Meeting when it was decided to fix the maximum magnetic rigidity of ion beams to 14.47 T.m (3.5 GeV equivalent proton energy) and to adopt a ring physical radius of 40 m in order to facilitate injectio...

  15. Fusion Rings for Quantum Groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Stroppel, Catharina

    2012-01-01

    We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from [12] and give a similar description of the sp2n-fusion ring in terms of noncommutative symmetric...

  16. RINGED ACCRETION DISKS: EQUILIBRIUM CONFIGURATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Pugliese, D.; Stuchlík, Z., E-mail: d.pugliese.physics@gmail.com, E-mail: zdenek.stuchlik@physics.cz [Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Faculty of Philosophy and Science, Silesian University in Opava, Bezručovo náměstí 13, CZ-74601 Opava (Czech Republic)

    2015-12-15

    We investigate a model of a ringed accretion disk, made up by several rings rotating around a supermassive Kerr black hole attractor. Each toroid of the ringed disk is governed by the general relativity hydrodynamic Boyer condition of equilibrium configurations of rotating perfect fluids. Properties of the tori can then be determined by an appropriately defined effective potential reflecting the background Kerr geometry and the centrifugal effects. The ringed disks could be created in various regimes during the evolution of matter configurations around supermassive black holes. Therefore, both corotating and counterrotating rings have to be considered as being a constituent of the ringed disk. We provide constraints on the model parameters for the existence and stability of various ringed configurations and discuss occurrence of accretion onto the Kerr black hole and possible launching of jets from the ringed disk. We demonstrate that various ringed disks can be characterized by a maximum number of rings. We present also a perturbation analysis based on evolution of the oscillating components of the ringed disk. The dynamics of the unstable phases of the ringed disk evolution seems to be promising in relation to high-energy phenomena demonstrated in active galactic nuclei.

  17. Assessment of precipitates of isothermal aged austenitic stainless steel using measurement techniques of ultrasonic attenuation

    International Nuclear Information System (INIS)

    Kim, Hun Hee; Kim, Hak Joon; Song, Sung Jin; Lim, Byeong Soo; Kim, Kyung Cho

    2014-01-01

    AISI 316L stainless steel is widely used as a structural material of high temperature thermoelectric power plants, since austenitic stainless steel has excellent mechanical properties. However, creep damage is generated in these components, which are operated under a high temperature and high pressure environment. Several researches have been done on how microstructural changes of precipitates affect to the macroscopic mechanical properties. And they investigate the relation between ultrasonic parameters and metallurgical results. But, these studies are limited by experiment results only. In this paper, attenuations of ultrasonic with isothermal damaged AISI 316L stainless steel were measured. Also, simulation of ultrasonic attenuation with variation of area fraction and size of precipitates were performed. And, from the measured attenuations, metallographic data and simulation results, we investigate the relations between the ultrasonic attenuations and the material properties which is area fraction of precipitates for the isothermal damaged austenitic stainless steel specimens. And, we studied parametric study for investigation of the relation between ultrasonic parameters and metallurgical results of the isothermal damaged AISI 316L stainless steel specimens using numerical methods.

  18. NEET In-Pile Ultrasonic Sensor Enablement-FY 2012 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    JE Daw; JL Rempe; BR Tittmann; B Reinhardt; P Ramuhalli; R Montgomery; HT Chien

    2012-09-01

    Several Department Of Energy-Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials when irradiated. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive. Ultrasonic technologies offer the potential to measure a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes, under harsh irradiation test conditions. There are two primary issues associated with in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. Due to the harsh nature of in-pile testing, and the range of measurements that are desired, an enhanced signal processing capability is needed to make in-pile ultrasonic sensors viable. This project addresses these technology deployment issues.

  19. Quality control of disinfection in ultrasonic baths

    Energy Technology Data Exchange (ETDEWEB)

    Schoene, H. [Technical University Dresden (Germany). Faculty of Mechanical Engineering; Jatzwauk, L. [University Hospital of the Technical University Dresden (Germany). Abt. Krankenhaushygiene

    2002-07-01

    Numerous investigations under laboratory conditions confirmed the microbicidal efficacy of ultrasonication. Morphological destruction was shown on bacteria and fungi as well as on different virus species. Ultrasonic treatment seems to increase the effect of different antibiotics and disinfectants. Reasons for this synergism are largely unknown and uninvestigated, but the active principle seems to bee the dispersing effect of ultrasonication in combination with the destruction of cell wall or cell membrane. Unfortunately no validation of test conditions exists for most of these investigations, regarding intensity and frequency of ultrasonic waves, temperature of liquid medium and measurement of cavitation which is an essential part of physical and chemical effects in ultrasonic baths. In contrast to most laboratory experiments sound density of ultrasound for treatment of medical instruments is below 1 W/cm{sup 2} because instruments will be destroyed under stronger ultrasonic conditions. The frequency is below 50 KHz. This paper describes bactericidal and fungicidal effects of low- intensity-ultrasonication and its synergistical support to chemical disinfection. (orig.)

  20. Characterization of the ultrasonic welding process in the production of women's health devices

    International Nuclear Information System (INIS)

    Morales Elizondo, Jenniffer

    2014-01-01

    The characterization of the ultrasonic welding process in the area of women's health is performed to determine appropriate levels for the critical variables of the process to guarantee the quality specifications of the devices. The handle of the product A is detached. The assembly was made under pressure. Available technologies have been studied to comply with the regulations of medical industry to propose a change in process to a product B. The ultrasonic technology is used to weld the handle of the device to prevent the release of the two parts of the handle of the medical device. A variable characterization process was performed to determine which variables are critical to the process and define the operation parameters of ultrasonic welding. A number of designs of experiments is carried out, first the parameters behavior of the equipment is evaluated to analyze which have greater influence on the quality of the weld. A full factorial design was developed with all process input variables and input variables that are significant was performed another series of designs of experiments to determine the parameters of the process.The conclusion for the ultrasonic welding process in the product B has been that the critical variables or that have had a greater influence on the quality and appearance in experienced designs are: pressure and soldier collapse. The process of ultrasonic welded cycle has started to arrive at the value of driving force that tells the computer. The input variable is recommended to be the lowest possible to weld components using the ordering of particles product of ultrasonic welded avoiding compression component. (author) [es

  1. Small electrostatic storage rings; also for highly charged ions?

    International Nuclear Information System (INIS)

    Moeller, S.P.; Pedersen, U.V.

    2001-01-01

    Two years ago, a small electrostatic storage ring ELISA (electrostatic ion storage ring, Aarhus) was put into operation. The design of this small 7 m circumference ring was based on electrostatic deflection plates and quadrupoles. This is in contrast to the larger ion storage rings, which are based on magnetic focusing and deflection. The result is a small, relatively inexpensive, storage ring being able to store ions of any mass and any charge at low energy ( -11 mbar resulting in storage times of several tens of seconds for singly charged ions. The maximum number of singly charged ions that can be stored is a few 10 7 . Several experiments have already been performed in ELISA. These include lifetime studies of metastable ions and studies of fullerenes and metal-cluster ions. Lasers are also used for excitation of the circulating ions. Heating/cooling of the ring is possible. Cooling of the ring leads to significantly lower pressures, and correspondingly longer lifetimes. A change of the temperature of the vacuum chambers surrounding the ion beam also leads to a change of the spectrum of the black-body radiation, which has a significant influence on weakly bound negative ions. At the time of writing, at least two other electrostatic storage rings are being built, and more are planned. In the following, the electrostatic storage ring ELISA will be described, and results from some of the initial experiments demonstrating the performance will be shown. The relative merits of such a ring, as opposed to the larger magnetic rings and the smaller ion traps will be discussed. The potential for highly charged ions will be briefly mentioned. (orig.)

  2. Pressure Dome for High-Pressure Electrolyzer

    Science.gov (United States)

    Norman, Timothy; Schmitt, Edwin

    2012-01-01

    A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom

  3. Novel Fiber-Optic Ring Acoustic Emission Sensor.

    Science.gov (United States)

    Wei, Peng; Han, Xiaole; Xia, Dong; Liu, Taolin; Lang, Hao

    2018-01-13

    Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

  4. Novel Fiber-Optic Ring Acoustic Emission Sensor

    Directory of Open Access Journals (Sweden)

    Peng Wei

    2018-01-01

    Full Text Available Acoustic emission technology has been applied to many fields for many years. However, the conventional piezoelectric acoustic emission sensors cannot be used in extreme environments, such as those with heavy electromagnetic interference, high pressure, or strong corrosion. In this paper, a novel fiber-optic ring acoustic emission sensor is proposed. The sensor exhibits high sensitivity, anti-electromagnetic interference, and corrosion resistance. First, the principle of a novel fiber-optic ring sensor is introduced. Different from piezoelectric and other fiber acoustic emission sensors, this novel sensor includes both a sensing skeleton and a sensing fiber. Second, a heterodyne interferometric demodulating method is presented. In addition, a fiber-optic ring sensor acoustic emission system is built based on this method. Finally, fiber-optic ring acoustic emission experiments are performed. The novel fiber-optic ring sensor is glued onto the surface of an aluminum plate. The 150 kHz standard continuous sinusoidal signals and broken lead signals are successfully detected by the novel fiber-optic ring acoustic emission sensor. In addition, comparison to the piezoelectric acoustic emission sensor is performed, which shows the availability and reliability of the novel fiber-optic ring acoustic emission sensor. In the future, this novel fiber-optic ring acoustic emission sensor will provide a new route to acoustic emission detection in harsh environments.

  5. Ultrasonic tests on materials with protective coatings

    International Nuclear Information System (INIS)

    Whaley, H.L.

    1977-01-01

    Protective coatings are applied to some nuclear components such as reactor vessels to inhibit surface corrosion. Since in-service ultrasonic inspection is required for such components, a study was performed to determine whether the use of protective coatings can affect ultrasonic tests. Two 2 in. thick steel plates were uniformly machined, sandblasted, and used as bases for two types of protective coatings. The type and thickness of the coating and the presence of contamination, such as fingerprints or mild oxidation under the paint, were the independent variables associated with the coating. Tests were run to determine the effects of the protective coatings on ultrasonic tests conducted on the steel plates. Significant variations in ultrasonic test sensitivity occurred as a function of the type and thickness of protective coating, couplant (material that conducts the ultrasound from the transducer into the test part, normally water or some type of oil), transducer wear plate, and ultrasonic test frequency. Ultrasonic tests can be strongly affected by a protective coating on the component to be inspected. As compared to the test sensitivity for an uncoated reference sample, the sensitivity may be dramatically shifted up or down on the coated surface. In certain coating thickness ranges, the sensitivity can fluctuate widely with small changes in coating thickness. If a coating is chosen properly, however, components with protective coatings can be tested ultrasonically with valid results. These results are for the case of ultrasonic input on the coated surface. It is not expected that an ultrasonic test conducted from the front surface would be appreciably affected by a coating on the rear surface

  6. Ring Confidential Transactions

    Directory of Open Access Journals (Sweden)

    Shen Noether

    2016-12-01

    Full Text Available This article introduces a method of hiding transaction amounts in the strongly decentralized anonymous cryptocurrency Monero. Similar to Bitcoin, Monero is a cryptocurrency which is distributed through a proof-of-work “mining” process having no central party or trusted setup. The original Monero protocol was based on CryptoNote, which uses ring signatures and one-time keys to hide the destination and origin of transactions. Recently the technique of using a commitment scheme to hide the amount of a transaction has been discussed and implemented by Bitcoin Core developer Gregory Maxwell. In this article, a new type of ring signature, A Multilayered Linkable Spontaneous Anonymous Group signature is described which allows one to include a Pedersen Commitment in a ring signature. This construction results in a digital currency with hidden amounts, origins and destinations of transactions with reasonable efficiency and verifiable, trustless coin generation. The author would like to note that early drafts of this were publicized in the Monero Community and on the #bitcoin-wizards IRC channel. Blockchain hashed drafts are available showing that this work was started in Summer 2015, and completed in early October 2015. An eprint is also available at http://eprint.iacr.org/2015/1098.

  7. Anomalies of ultrasound attenuation in metals under hydrostatic pressure

    International Nuclear Information System (INIS)

    Galkin, A.A.; Datsko, O.I.; Varyukhin, V.N.; Pilipenko, N.P.

    1978-01-01

    Ultrasonic attenuation was measured in polycrystal specimens of molybdenum, chromium and zinc under hydrostatic pressure up to 6 kbar. On the plot of ultrasound attenuation dependence on the pressure in molybdenum the maxima are observed under the pressure of 2 kbar. The anomaly of ultrasound attenuation is shown to connect only with brittle-ductile transtion

  8. Ultrasonic splitting of oil-in-water emulsions

    DEFF Research Database (Denmark)

    Hald, Jens; König, Ralf; Benes, Ewald

    1999-01-01

    Standing resonant ultrasonic wave fields can be utilized for liquid–liquid separation of the dispersed particles and the fluid caused by the acoustic radiation pressure and the induced particle agglomeration or coagulation/coalescence process. For the splitting of oil-in-water emulsions, the avai......Standing resonant ultrasonic wave fields can be utilized for liquid–liquid separation of the dispersed particles and the fluid caused by the acoustic radiation pressure and the induced particle agglomeration or coagulation/coalescence process. For the splitting of oil-in-water emulsions......, the available piezoelectric composite transducer technology was improved and a dedicated resonator with crossed plane wave sonication geometry has been developed. The resonator chamber is entirely made of aluminium or tempax glass and the PZT piezoceramic transducer delivers an acoustic energy flow density...... of up to 24 W/cm2 into the sonication volume. The chosen resonance frequency is kept stable by automatic frequency control utilizing the maximum true power criterion. Physically and chemically well-defined low and high density pure laboratory and also industrially used cooling-lubricating oil...

  9. Computer simulation of ultrasonic waves in solids

    International Nuclear Information System (INIS)

    Thibault, G.A.; Chaplin, K.

    1992-01-01

    A computer model that simulates the propagation of ultrasonic waves has been developed at AECL Research, Chalk River Laboratories. This program is called EWE, short for Elastic Wave Equations, the mathematics governing the propagation of ultrasonic waves. This report contains a brief summary of the use of ultrasonic waves in non-destructive testing techniques, a discussion of the EWE simulation code explaining the implementation of the equations and the types of output received from the model, and an example simulation showing the abilities of the model. (author). 2 refs., 2 figs

  10. Ultrasonic characterization of vegetable oil product

    International Nuclear Information System (INIS)

    Sidek Hj Abd Aziz; Chow Sai Pew; Abdul Halim Shaari; Nor Azizah Shaari

    1992-01-01

    The ultrasonic wave velocity and attenuation of a number vegetable oil products were measured using an ultrasonic pulse echo overlap technique from room temperature up to 90 0 C. Among the liquid samples studied were refined bleach deodorized (RED) palm oil, palm olein, coconut oil, corn oil and soya bean oil. The velocity of sound in vegetable oil products varies from about 1200 to 200 ms-1 and decrease linearly as the temperature increases. The ultrasonic properties of the oil are much dependent on their viscosity, density, relaxation effect and vibrational anharmonicity

  11. On-line ultrasonic gas entrainment monitor

    International Nuclear Information System (INIS)

    Day, C.K.; Pedersen, H.N.

    1978-01-01

    Apparatus employing ultrasonic energy for detecting and measuring the quantity of gas bubbles present in liquids being transported through pipes is described. An ultrasonic transducer is positioned along the longitudinal axis of a fluid duct, oriented to transmit acoustic energy radially of the duct around the circumference of the enclosure walls. The back-reflected energy is received centrally of the duct and interpreted as a measure of gas entrainment. One embodiment employs a conical reflector to direct the transmitted acoustic energy radially of the duct and redirect the reflected energy back to the transducer for reception. A modified embodiment employs a cylindrical ultrasonic transducer for this purpose

  12. Fundamentals and applications of ultrasonic waves

    CERN Document Server

    Cheeke, J David N

    2002-01-01

    Ultrasonics. A subject with applications across all the basic sciences, engineering, medicine, and oceanography, yet even the broader topic of acoustics is now rarely offered at undergraduate levels. Ultrasonics is addressed primarily at the doctoral level, and texts appropriate for beginning graduate students or newcomers to the field are virtually nonexistent.Fundamentals and Applications of Ultrasonic Waves fills that void. Designed specifically for senior undergraduates, beginning graduate students, and those just entering the field, it begins with the fundamentals, but goes well beyond th

  13. Fusion Rings for Quantum Groups

    DEFF Research Database (Denmark)

    Andersen, Henning Haahr; Stroppel, Catharina

    2014-01-01

    We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from Korff, C., Stroppel, C.: The sl(ˆn)k-WZNW fusion ring: a combinato-rial construction...... and a realisation as quotient of quantum cohomology. Adv. Math. 225(1), 200–268, (2010) and give a similar description of the sp2n-fusion ring in terms of non-commutative symmetric functions. Moreover we give a presentation of all fusion rings in classical types as quotients of polynomial rings. Finally we also...... compute the fusion rings for type G2....

  14. Cracks assessment using ultrasonic technology

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Maria Pia; Tomasella, Marcelo [OLDELVAL S.A. Oleoductos del Valle, Rio Negro (Argentina). Pipeline Integrity Dept.

    2005-07-01

    The goal of Oldelval Integrity Program is to prevent ruptures and leaks, developing strategies for a better handling of the integrity of our pipelines. In order to achieve it we have studied and modeled each process that involved in the integrity pipeline. Those processes are mainly based on defects reported by an internal inspection tool and supplied with field inspection and monitoring data. Years of evaluation, study and the continuous effort overturned towards a phenomenon that worries to the industry, as it is the SCC. Since 1998 up to 2004 SCC was included in the integrity program with some preventive maintenance programs. The accomplishment of the inspection based on ultrasound tools, is the culmination of years of evaluation and investigations supported by field digs and materials susceptibility. This paper describes Oldelval's results with ultrasonic crack detection tool, and how it can be reliably to detect SCC. (author)

  15. Integrated Ultrasonic-Photonic Devices

    DEFF Research Database (Denmark)

    Barretto, Elaine Cristina Saraiva

    in channel waveguides and Mach-Zehnder interferometers. Numerical models are developed based on the finite element method, and applied to several scenarios, such as optimization of the geometrical parameters of waveguides, use of slow light in photonic crystal waveguides and use of Lamb waves in membranized......This thesis deals with the modeling, design, fabrication and characterization of integrated ultrasonic-photonic devices, with particular focus on the use of standard semiconductor materials such as GaAs and silicon. The devices are based on the use of guided acoustic waves to modulate the light...... investigated. Comparisons are made with the numerical and experimental results, and they validate the obtained response of the acoustic and photonic components of the device. Finally, a new design for an optical frequency shifter is proposed, posing several advantages over existing devices in terms of size...

  16. Ultrasonic Histotripsy for Tissue Therapy

    Science.gov (United States)

    Pahk, K. J.; Dhar, D. K.; Malago, M.; Saffari, N.

    2015-01-01

    Hepatocyte transplantation has been considered and investigated as a promising and alternative method to liver transplantation for treating liver-based metabolic disorder in newborns over the past two decades. Although some clinical trials have been conducted and shown clinical benefits and outcomes, it is difficult to deliver and achieve a desired level of integration and transplantation of hepatocytes in the liver parenchyma. To overcome this problem, this work introduces an alternative method to a portal-infused-hepatocyte cell transplantation. To improve the level of engraftment of transplantable hepatocytes, these are injected directly into cavities generated by ultrasonic histotripsy. Histotripsy is an extracorporeal noninvasive technique which has been recently developed using high intensity focused ultrasound (HIFU) for inducing tissue fractionation with no coagulative necrosis. The exact mechanisms for the tissue fractionation are not well understood yet; but the possible mechanisms are thought to be a combination of nonlinear wave propagation effect, explosive bubble growth and ultrasonic atomization. The main objectives of this work are to demonstrate the feasibility of this new cell therapy and evaluate and distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion. In the present work, numerical studies on the bubble dynamics (the Gilmore-Akulichev bubble model coupled with the Khokhlov-Zabolotskaya-Kuznetsov equation) and both ex- and in vivo liver experiments are conducted with histological analysis (haematoxylin and eosin stain). The numerical and the experimental results suggest that (a) the acoustic emissions emitted during the thermal ablation and the histotripsy exposure can be distinguished both numerically and experimentally and (b) the proposed cell therapy may potentially form an effective and safe clinical treatment for replacing and correcting disordered hepatocytes, although the

  17. Ultrasonic Histotripsy for Tissue Therapy

    International Nuclear Information System (INIS)

    Pahk, K J; Saffari, N; Dhar, D K; Malago, M

    2015-01-01

    Hepatocyte transplantation has been considered and investigated as a promising and alternative method to liver transplantation for treating liver-based metabolic disorder in newborns over the past two decades. Although some clinical trials have been conducted and shown clinical benefits and outcomes, it is difficult to deliver and achieve a desired level of integration and transplantation of hepatocytes in the liver parenchyma. To overcome this problem, this work introduces an alternative method to a portal-infused-hepatocyte cell transplantation. To improve the level of engraftment of transplantable hepatocytes, these are injected directly into cavities generated by ultrasonic histotripsy. Histotripsy is an extracorporeal noninvasive technique which has been recently developed using high intensity focused ultrasound (HIFU) for inducing tissue fractionation with no coagulative necrosis. The exact mechanisms for the tissue fractionation are not well understood yet; but the possible mechanisms are thought to be a combination of nonlinear wave propagation effect, explosive bubble growth and ultrasonic atomization. The main objectives of this work are to demonstrate the feasibility of this new cell therapy and evaluate and distinguish between the different types of cavitation activity for either a thermally or a mechanically induced lesion. In the present work, numerical studies on the bubble dynamics (the Gilmore-Akulichev bubble model coupled with the Khokhlov-Zabolotskaya-Kuznetsov equation) and both ex- and in vivo liver experiments are conducted with histological analysis (haematoxylin and eosin stain). The numerical and the experimental results suggest that (a) the acoustic emissions emitted during the thermal ablation and the histotripsy exposure can be distinguished both numerically and experimentally and (b) the proposed cell therapy may potentially form an effective and safe clinical treatment for replacing and correcting disordered hepatocytes, although the

  18. Tree Rings: Timekeepers of the Past.

    Science.gov (United States)

    Phipps, R. L.; McGowan, J.

    One of a series of general interest publications on science issues, this booklet describes the uses of tree rings in historical and biological recordkeeping. Separate sections cover the following topics: dating of tree rings, dating with tree rings, tree ring formation, tree ring identification, sample collections, tree ring cross dating, tree…

  19. Ultrasonically-assisted Thermal Stir Welding System

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2014-01-01

    A welding head assembly has a work piece disposed between its containment plates' opposing surfaces with the work piece being maintained in a plastic state thereof at least in a vicinity of the welding head assembly's stir rod as the rod is rotated about its longitudinal axis. The welding head assembly and the work piece experience relative movement there between in a direction perpendicular to the rod's longitudinal axis as the work piece is subjected to a compressive force applied by the containment plates. A first source coupled to the first containment plate applies a first ultrasonic wave thereto such that the first ultrasonic wave propagates parallel to the direction of relative movement. A second source coupled to the second containment plate applies a second ultrasonic wave thereto such that the second ultrasonic wave propagates parallel to the direction of relative movement.propagates parallel to the direction of relative movement.

  20. Ultrasonic determination of the size of defects

    International Nuclear Information System (INIS)

    Zetterwall, T.

    1989-01-01

    The paper presents results from a study of ultrasonic testing of materials. The main topic has been the determination of the size, length and deep, of cracks or defects in stainless steel plates. (K.A.E)

  1. Advanced ultrasonic technology for natural gas measurement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    In recent years, due to rising environmental and safety concerns, increasing commodity prices, and operational inefficiencies, a paradigm shift has been taking place with respect to gas measurement. The price of natural gas depends on the location, time of the year, and type of consumer. There is wide uncertainty associated with an orifice meter. This paper presents the use of advanced ultrasonic technology for the measurement of natural gas. For many years, multi-path ultrasonic meters with intelligent sensor technology have been used for gas measurement. This paper gives the various applications of ultrasonic technology along with their advantages and a draws a comparison with orifice meters. From the study it can be concluded that extensive advances in the use of ultrasonic technology for gas measurement have widened the areas of application and that varying frequencies combined with sealed transducer designs make it possible to measure atmospheric and sour gas in custody transfer process control and flaring accurately.

  2. Ultrasonic assisted hot metal powder compaction.

    Science.gov (United States)

    Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

    2017-09-01

    Hot pressing of metal powders is used in production of parts with similar properties to wrought materials. During hot pressing processes, particle rearrangement, plastic deformation, creep, and diffusion are of the most effective powder densification mechanisms. Applying ultrasonic vibration is thought to result in great rates of densification and therefore higher efficiency of the process is expected. This paper deals with the effects of power ultrasonic on the densification of AA1100 aluminum powder under constant applied stress. The effects of particle size and process temperature on the densification behavior are discussed. The results show that applying ultrasonic vibration leads to an improved homogeneity and a higher relative density. Also, it is found that the effect of ultrasonic vibration is greater for finer particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Hand Gesture Recognition Using Ultrasonic Waves

    KAUST Repository

    AlSharif, Mohammed Hussain

    2016-01-01

    estimation of the moving hand and received signal strength (RSS). These two factors are estimated using two simple methods; channel impulse response (CIR) and cross correlation (CC) of the reflected ultrasonic signal from the gesturing hand. A customized

  4. Ultrasonic Morphological Analyzers for Breast Cancer Diagnosis

    National Research Council Canada - National Science Library

    Lizzi, Frederic

    1999-01-01

    The goal of this research is to improve ultrasonic classification of breast lesions and guide decisions regarding biopsy requirements, especially for small lesions and those in young, dense breasts...

  5. Rail inspection using noncontact laser ultrasonics

    International Nuclear Information System (INIS)

    Kim, Nak Hyeon; Sohn, Hoon; Han, Soon Woo

    2012-01-01

    In this study, a noncontact laser ultrasonic system is proposed for rail defect detection. An Nd Yag pulse laser is used for generation of ultrasonic waves, and the corresponding ultrasonic responses are measured by a laser Doppler vibrometer. For the detection of rail surface damages, the shape of the excitation laser beam is transformed into a line. On the other hand, a point source laser beam is used for the inspection of defects inside a rail head. Then, the interactions of propagating ultrasonic waves with defects are examined using actual rail specimens. Amplitude attenuation was mainly observed for a surface crack, and reflections were most noticeable from an internal damage. Finally, opportunities and challenges associated with real time rail inspection from a high speed train are discussed

  6. Nondestructive control of materials by ultrasonic tests

    International Nuclear Information System (INIS)

    Mercier, Noelle.

    1974-01-01

    A bibliographic study of nondestructive control methods of solids by ultrasonic tests, and of the ultrasonic emission of a transducer of finite dimension, is first presented. The principle of two of these methods is verified experimentally; they should permit the measurement of various physical parameters of solids, and the detection of local inhomogeneities. The first method calls upon the analysis of the ultrasonic signal (amplitude and phase), after it has crossed a constant thickness of a metallic specimen. This analysis reveals variations of attenuation and of ultrasonic propagation velocity within the specimen. A good spatial resolution is obtained by using 1mm-diameter probes. The second method leads, thanks to a test rig equipped with broad frequency band electrostatic transducers, to the knowledge of the attenuation law of the specimens as a function of frequency (present range: 5 to 15MHz); from this a classification of these specimens as regards their granulometry is deduced [fr

  7. Ultrasonic testing of materials at level 2

    International Nuclear Information System (INIS)

    1988-06-01

    Ultrasonic inspection is a nondestructive method in which high frequency sound waves are introduced into the material being inspected. Ultrasonic testing has a superior penetrating power to radiography and can detect flaws deep in the test specimen (say up to about 6 to 7 meters of steel). It is quite sensitive to small flaws and allows the precise determination of the location and size of the flaws. Basic ultrasonic test methods such as the through transmission method and the resonance method, sensors and testing techniques are described. Pulse echo type flaw detectors and their applications for inspection of welds are surveyed. Ultrasonic standards, calibration of the equipment and evaluation methods are presented. Examples of practical applications in welding, casting and forging processes are given. Figs and tabs

  8. Improvement of Ultrasonic Distance Measuring System

    Directory of Open Access Journals (Sweden)

    Jiang Yu

    2018-01-01

    Full Text Available This paper mainly introduces a kind of ultrasonic distance measuring system with AT89C51 single chip as the core component. The paper expounds the principle of ultrasonic sensor and ultrasonic ranging, hardware circuit and software program, and the results of experiment and analysis.The hardware circuit based on SCM, the software design adopts the advanced microcontroller programming language.The amplitude of the received signal and the time of ultrasonic propagation are regulated by closed loop control. [1,2]The double closed loop control technology for amplitude and time improves the measuring accuracy of the instrument. The experimental results show that greatly improves the measurement accuracy of the system.

  9. Influence of pressure on acoustic and rheologic parameters in water solutions of laury sodium sulfate

    Science.gov (United States)

    Khamidov, B. T.; Lezhnev, N. B.

    1995-10-01

    Ultrasonic velocity and density in water solutions of lauril sodium sulphate at frequency 36 MHz, within the range of pressures from 0.1 to 105 MPa at temperature T equals 293 K were measured. According to data of ultrasonic velocity and density under high pressures there was calculated adiabatic compressibility in objects studied from pressure. It was found out that the region of critical concentration of micelle formation has been shifted to the zone of much more low concentrations.

  10. Graphite Microstructural Characterization Using Time-Domain and Correlation-Based Ultrasonics

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, James [Johns Hopkins Univ., Baltimore, MD (United States)

    2017-12-06

    Among techniques that have been used to determine elastic modulus in nuclear graphites, ultrasonic methods have enjoyed wide use and standards using contacting piezoelectric tranducers have been developed to ensure repeatability of these types of measurements. However, the use of couplants and the pressures used to effectively couple transducers to samples can bias measurements and produce results that are not wholly related to the properties of the graphite itself. In this work, we have investigated the use of laser ultrasonic methods for making elastic modulus measurements in nuclear graphites. These methods use laser-based transmitters and receivers to gather data and do not require use of ultrasonic couplants or mechanical contact with the sample. As a result, information directly related to the elastic responses of graphite can be gathered even if the graphite is porous, brittle and compliant. In particular, we have demonstrated the use of laser ultrasonics for the determination of both Young’s modulus and shear modulus in a range of nuclear graphites including those that are being considered for use in future nuclear reactors. These results have been analyzed to assess the contributions of porosity and microcracking to the elastic responses of these graphites. Laser-based methods have also been used to assess the moduli of NBG-18 and IG-110 where samples of each grade were oxidized to produce specific changes in porosity. These data were used to develop new models for the elastic responses of nuclear graphites and these models have been used to infer specific changes in graphite microstructure that occur during oxidation that affect elastic modulus. Specifically, we show how ultrasonic measurements in oxidized graphites are consistent with nano/microscale oxidation processes where basal plane edges react more readily than basal plane surfaces. We have also shown the use of laser-based methods to perform shear-wave birefringence measurements and have shown

  11. The multi-element ultrasonic technology: examples of application on military naval structures

    International Nuclear Information System (INIS)

    Recolin, P.; Rivalin, S.

    2009-01-01

    DCNS is the European leader in the military ship construction and maintenance (conventional and nuclear propulsion). The potential of ultrasonic technologies with multi-element probes has been studied in its Materials laboratory since the end of the 80's, and a growing number of applications has appeared these last ten years. A series of examples is given: in-service nuclear reactor pipe welds monitoring, time-of-flight diffraction (TOFD) technique for the inspection of containment welds, coating fabrication control, detection of laminating corrosion on aluminum rings, detection of corrosion on submarine hulls in basin, inspection of hull welded joints

  12. Ultrasonic Generation and Optimization for EMAT

    International Nuclear Information System (INIS)

    Jian, X.; Dixon, Steve; Edwards, Rachel S.

    2005-01-01

    A model for transient ultrasonic wave generation by EMATs in non-magnetic metals is presented. It combines analytical solutions currently available and FEM to calculate ultrasonic bulk and Rayleigh waves generated by the EMAT. Analytical solutions are used as they can be calculated quickly on a standard mathematical computer package. Calculations agree well with the experimental measurement. The model can be used to optimize EMAT design, and has explained some of the results from our previous published measurements

  13. Extrinsic Fabry-Perot ultrasonic detector

    Science.gov (United States)

    Kidwell, J. J.; Berthold, John W., III

    1996-10-01

    We characterized the performance of a commercial fiber optic extrinsic Fabry-Perot interferometer for use as an ultrasonic sensor, and compared the performance with a standard lead zirconate titanate (PZT) detector. The interferometer was unstabilized. The results showed that the fiber sensor was about 12 times less sensitive than the PZT detector. Ultrasonic frequency response near 100 kHz was demonstrated. We describe the design of the fiber sensor, the details of the tests performed, and potential applications.

  14. An advanced system for automated ultrasonic testing

    International Nuclear Information System (INIS)

    Dressler, K.

    1989-01-01

    As the main component of the AUP system, an ALOK ultrasonic unit has been chosen as it allows for testing of large component areas both search for defects and description of defect geometries. All data required for fault analysis can be obtained by one measuring run. For inspection of primary circuit components in nuclear power stations, the manipulator control and the ultrasonic probe are installed behind the first sufficient shielding. (orig./HP) [de

  15. Fundamentals and Applications of Ultrasonic Waves

    CERN Document Server

    Cheeke, J David N

    2012-01-01

    Designed specifically for newcomers to the field, this fully updated second edition begins with fundamentals and quickly advances beyond general wave concepts into an in-depth treatment of ultrasonic waves in isotropic media. Focusing on the physics of acoustic waves, their propagation, technology, and applications, this accessible overview of ultrasonics includes accounts of viscoelasticity and multiple scattering. It examines new technologies, including atomic force acoustic microscopy, lasers, micro-acoustics, and nanotechnology. In addition, it highlights both direct and indirect applicati

  16. Longitudinal ultrasonic waves dispersion in bars

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2001-01-01

    The exhibition intends to review some aspects of the propagation of the longitudinal ultrasonic pulses shortly in bars of traverse section uniform.Aspects they are part of the denominated geometric dispersion of the pulses.This phenomenon It can present like an additional complication in the ultrasonic essay of low frequency of thin pieces in structures and machines but takes place former ex professed in some applications of the wave guides been accustomed to in the prosecution of signs

  17. SOR-ring failure

    International Nuclear Information System (INIS)

    Kitamura, Hideo

    1981-01-01

    It was in the autumn of 1976 that the SOR-ring (synchrotron radiation storage ring) has commenced the regular operation. Since then, the period when the operation was interrupted due to the failures of SOR-ring itself is in total about 8 weeks. Failures and accidents have occurred most in the vacuum system. Those failure experiences are described on the vacuum, electromagnet, radio-frequency acceleration and beam transport systems with their interrupted periods. The eleven failures in the vacuum system have been reported, such as bellows breakage in a heating-evacuating period, leakage from the bellows of straight-through valves (made in U.S.A. and Japan), and leakage from the joint flange of the vacuum system. The longest interruption was 5 weeks due to the failure of a domestically manufactured straight-through valve. The failures of the electromagnet system involve the breakage in a cooling water system, short circuit of a winding in the Q magnet power transformer, blow of a fuse protecting the deflection magnet power source by the current less than the rating, and others. The failures of the RF acceleration system include the breakage of an output electronic tube the breakage of a cavity ceramic, RF voltage fluctuation due to the contact deterioration at a cavity electrode, and the failure of grid bias power source. It is necessary to select the highly reliable components for the vacuum system because the vacuum system failures require longer time for recovery, and very likely to induce secondary and tertiary failures. (Wakatsuki, Y.)

  18. Proton storage rings

    International Nuclear Information System (INIS)

    Rau, R.R.

    1978-04-01

    A discussion is given of proton storage ring beam dynamic characteristics. Topics considered include: (1) beam energy; (2) beam luminosity; (3) limits on beam current; (4) beam site; (5) crossing angle; (6) beam--beam interaction; (7) longitudinal instability; (8) effects of scattering processes; (9) beam production; and (10) high magnetic fields. Much of the discussion is related to the design parameters of ISABELLE, a 400 x 400 GeV proton---proton intersecting storage accelerator to be built at Brookhaven National Laboratory

  19. Ring-constrained Join

    DEFF Research Database (Denmark)

    Yiu, Man Lung; Karras, Panagiotis; Mamoulis, Nikos

    2008-01-01

    . This new operation has important applications in decision support, e.g., placing recycling stations at fair locations between restaurants and residential complexes. Clearly, RCJ is defined based on a geometric constraint but not on distances between points. Thus, our operation is fundamentally different......We introduce a novel spatial join operator, the ring-constrained join (RCJ). Given two sets P and Q of spatial points, the result of RCJ consists of pairs (p, q) (where p ε P, q ε Q) satisfying an intuitive geometric constraint: the smallest circle enclosing p and q contains no other points in P, Q...

  20. Femtoslicing in Storage Rings

    CERN Document Server

    Khan, Shaukat

    2005-01-01

    The generation of ultrashort synchrotron radiation pulses by laser-induced energy modulation of electrons and their subsequent transverse displacement, now dubbed "femtoslicing," was demonstrated at the Advanced Light Source in Berkeley. More recently, a femtoslicing user facility was commissioned at the BESSY storage ring in Berlin, and another project is in progress at the Swiss Light Source. The paper reviews the principle of femtoslicing, its merits and shortcomings, as well as the variations of its technical implementation. Various diagnostics techniques to detect successful laser-electron interaction are discussed and experimental results are presented.