Rev Sci Instrum Research Articles

Q‐band to V‐band 1D and 2D elliptical lens antenna arrays

AbstractAn investigation of the receiving properties of both 1D 13‐element and 2D 8 × 4‐element dual dipole antenna arrays on an elliptical MACOR lens from Q‐ to V‐band is reported. Theoretical and measurement results agree well. The intended application is for millimeter wave plasma radar reflectometric imaging, although the results have broader applicability (Munsat et al., Rev Sci Instrum 74 (2003) 1426–1432). © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1798–1801, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22620

Simultaneous measurement of the concentration of a supercritical gas absorbed in a polymer and of the concomitant change in volume of the polymer. The coupled VW-pVT technique revisited

The purpose of this article is to re-examine the simultaneous measurements of the concentration of a supercritical gas in a polymer and of the concomitant change in volume of the polymer with the coupled VW-pVT technique [Hilic S, Pádua AAH, Grolier J-PE. Rev Sci Instrum 71 (11) (2000) 4236–41; Hilic S, Boyer SAE, Pádua AAH, Grolier J-PE. J Polym Sci B: Polym Phys 39 (2001) 2063–2070]. The experimental set-up consists of an original coupling of two techniques, a vibrating-wire sensor VW to weigh the polymer sample during the sorption and a pressure decay pVT-method to measure the quantity of gas, transferred from a high-pressure calibrated volume, which is absorbed by the polymer sample. The present study is related to the sorption and desorption of light gases (like CH4, CO2, H2S, N2) usually found in petroleum products circulating in pipelines made of semicrystalline polymers (like polyolefins and fluorinated polymers).Results for CO2 in medium-density polyethylene, MDPE, and in poly(vinylidene fluoride), PVDF (or PVF2), in the range of temperatures up to 391K and pressures up to 43MPa, are reported and discussed. Experiments allow the apparent concentration of gas dissolved in the polymer to be established; the associated swelling of the polymer is estimated using the Sanchez–Lacombe equation of state. Then, the data of the corrected concentration of the gas in the polymer are correlated with the semi-empirical ‘dual-mode’ model. Whenever possible to compare our results are in good agreement with existing literature data.

Simultaneous measurement of velocity and temperature in high-temperature turbulent flows: a combination of LDV and a three-wire temperature probe

This paper deals with a simple and reliable technique for simultaneous measurement of velocity and temperature in high-temperature turbulent flows, including combustion. The technique is based on the combination of laser Doppler velocimetry and a digitally compensated fine-wire thermocouple. For temperature measurement, a two-thermocouple probe with a fine cold wire [Tagawa et al. (1998) Rev Sci Instrum 69: 3370–3378] is used, which enables in situ measurement of thermocouple time constants and accurate compensation of the thermocouple response. When tested in a turbulent wake behind a heated cylinder, the technique proves to be highly reliable and effective for investigating heat transport processes in various non-isothermal turbulent flows.

A respiratory ozone analyzer optimized for high resolution and swift dynamic response during exercise conditions.

The breath-to-breath determination of total respiratory ozone (O3) uptake requires the monitoring of O3 concentration at the airway opening with an instrument that responds rapidly relative to the frequency of respiration. Originally, the authors developed an analyzer that used the homogeneous chemiluminescent reaction of O3 with 2-methyl-2-butene, but it was suitable only for monitoring O3 during quiet breathing and light exercise (Ben-Jebria and Ultman, Rev Sci Instrum 1989; 60:3004-11, and Ben-Jebria et al., Rev Sci Instrum 1990; 61:3435-39). The improvement of performance characteristics of the aforementioned analyzer enabled the authors to use the newly constructed and self-contained instrument, which used ethylene as the reactant gas, for respiratory O3 monitoring during moderate-to-heavy exercise. Operating at a reaction chamber pressure of 350 torr, an ethylene/sample flow ratio of 4:1, and a sampling flow of 0.6 lpm, the authors achieved an optimum analyzer performance (i.e., 10-90% step-response of 70 msec and a minimum resolution of 0.006 ppm O3). Furthermore, the new instrument did not exhibit the nonlinear calibration and the CO2 interference suffered by the original analyzer. To demonstrate the quality of the new O3 analyzer in a respiratory application (i.e., total O3 uptake), the authors measured a series of single breaths on two subjects who breathed 0.11 and 0.43 ppm O3-in-air mixtures for 15 min during rest, and during moderate and heavy exercise.

Detection and Localization of Early Lung Cancer by Imaging Techniques*

The detection and localization of lung cancer in the carcinoma in situ or the microinvasive stage offers an excellent prognosis for patients. However, these, small, early lung cancers are difficult to detect and localize even with conventional fiberoptic bronchoscopy. Several attempts have been made in the past to enhance the detection of early lung cancer by using fluorescent tumor markers such as hematoporphyrin derivatives. 1 Profio AE Doiron DR King EGL. Laser fluorescence bronchoscopy for localization of occult lung tumors. Med Phys. 1979; 6: 532-535 Crossref Scopus (80) Google Scholar , 2 Hirano T Ishizuka M Suzuki K Ishida K Suzuki S Miyaki S et al. Photodynamic cancer diagnosis and treatment system consisting of pulsed lasers and endoscopic spectro-image analyzer. Lasers Life Sci. 1989; 3: 1-18 Google Scholar , 3 Baumgartner R Fisslinger H Jocham D Lenz H Ruprecht L Stepp H et al. A fluorescence imaging device for endoscopic detection of early stage cancer—instrumental and experimental studies. Photochem Photobiol. 1987; 46: 759-763 Crossref PubMed Scopus (102) Google Scholar , 4 Montan S Svanberg K Svanberg S. Multicolor imaging and contrast enhancement in cancer-tumor localization using laser-induced fluorescence in hematoporphyrin-derivative-bearing tissue. Optics Letters. 1985; 10: 56-58 Crossref PubMed Scopus (74) Google Scholar , 5 Kinsey JH Cortese DA. Endoscopic system for simultaneous visual examination and electronic detection of fluorescence. Rev Sci Instrum. 1980; 51: 1403-1406 Crossref PubMed Scopus (27) Google Scholar , 6 Profio AE Doiron DR Sarnaik J. Fluorometer for endoscopic diagnosis of tumors. Med Phys. 1984; 11: 516-520 Crossref PubMed Scopus (45) Google Scholar , 7 Lam S Palcic B McLean D Hung J Korbelik M Profio AE. Detection of early lung cancer using low dose Photofrin II. Chest. 1990; 97: 333-337 Abstract Full Text Full Text PDF PubMed Scopus (89) Google Scholar A new method to image early lung cancer without the use of investigative drugs has been developed. This new procedure exploits spectral differences of the autofluorescence of normal and cancerous tissue. Fluorescence images at two (or more) characteristic spectral bands are amplified and captured by a sensitive image-intensified camera. These images are then digitized using a mathematical transformation and converted into a pseudo image that clearly delineates the cancerous area when displayed on a color video monitor.

Auger electron spectroscopy : method for the accurate measurement of signal and noise and a figure of merit for the performance of AES instrument sensitivity: M P Seah and C P Hunt, Rev Sci Instrum, 59, 1988, 217–227

Auger electron spectroscopy : method for the accurate measurement of signal and noise and a figure of merit for the performance of AES instrument sensitivity: M P Seah and C P Hunt, Rev Sci Instrum, 59, 1988, 217–227

Design and performance of an UHV beamline to produce low and hyperthermal energy ion beams: D L Adler and B H Cooper,Rev Sci Instrum,59, 1988, 137–145

Design and performance of an UHV beamline to produce low and hyperthermal energy ion beams: D L Adler and B H Cooper,Rev Sci Instrum,59, 1988, 137–145

Novel approach for particle velocity and size measurement under plasma conditions: Tadahiro Sakuta and Maher I Boulos, Rev Sci Instrum, 59, 1988, 285–291

Novel approach for particle velocity and size measurement under plasma conditions: Tadahiro Sakuta and Maher I Boulos, Rev Sci Instrum, 59, 1988, 285–291

Scanning differential polarization microscope : its use to image linear and circular differential scattering: William Mickols and Marcos F Maestre, Rev Sci Instrum, 59, 1988, 867–872

Scanning differential polarization microscope : its use to image linear and circular differential scattering: William Mickols and Marcos F Maestre, Rev Sci Instrum, 59, 1988, 867–872

Oscillating vane for measuring speed of gas flow: H H Johnsson and B Vonnegut,Rev Sci Instrum,59, 1988, 783–7786

Several Neutral Beam Injection (NBI) systems are now capable of injection of powers greater than 20 MW, some for pulse lengths in excess of 5 s. These high power NBI systems have demonstrated the flexibility and utility of neutral beam heating; coupling easily to many plasma configurations; providing heating, fuelling and current drive capability and allowing access to new, improved plasma confinement regimes. All the high power NBI systems have now achieved routinely high reliability and system availability (≥ 80–90%).The current status of NBI systems is reviewed and successful solutions to the technological problems encountered in design of high power beams, ranging from high heat transfer elements to large area cryopumps, are discussed. The interface to tokamak operations such as the drift duct, stray field cancellation and fast interlock mechanisms are presented, emphasising the considerable progress in these areas.The upgrading of NBI systems for tritium injection on JET and TFTR is reviewed.The possible parameters for a ‘Next Step’ injector are presented, showing the choice of negative ion beams as an attractive option. With reference to the existing conceptual designs for ITER/NET it is shown that the main areas of uncertainty exist in the source and accelerator stack designs. The beamlines themselves should be able to take advantage of the properties of negative ions to lead to some marked simplifications.

Reduction of the impurity concentration of an intense hydrogen ion beam: W Ott et al,Rev Sci Instrum, 54 (1), 1983, 50–55

Reduction of the impurity concentration of an intense hydrogen ion beam: W Ott et al,Rev Sci Instrum, 54 (1), 1983, 50–55

New technique for measuring win velocity: Govind S Khandelwal and Jag J Singh, Rev Sci Instrum, 53 (2), 1982, 239–244

New technique for measuring win velocity: Govind S Khandelwal and Jag J Singh, Rev Sci Instrum, 53 (2), 1982, 239–244

New operation mode of a microchannel plate for the detection of low-energy positive ions: Nobuyoshi Koshida and Norio Nagashima,Rev Sci Instrum,54 (1), 1983, 62–64

New operation mode of a microchannel plate for the detection of low-energy positive ions: Nobuyoshi Koshida and Norio Nagashima,Rev Sci Instrum,54 (1), 1983, 62–64

Scattered electron counting system for nozzle beam studies of small clusters: Sang S Kim and Gilbert D Stein,Rev Sci Instrum, 53 (6), 1982, 838–844

Scattered electron counting system for nozzle beam studies of small clusters: Sang S Kim and Gilbert D Stein,Rev Sci Instrum, 53 (6), 1982, 838–844

Ion-extraction performance of the circular magnetic-multipole bucket ion source applied for the neutral beam injection system of the Heliotron E machine: Fumimichi Sano et al,Rev Sci Instrum, 54 (1) 1983, 41–45

Ion-extraction performance of the circular magnetic-multipole bucket ion source applied for the neutral beam injection system of the Heliotron E machine: Fumimichi Sano et al,Rev Sci Instrum, 54 (1) 1983, 41–45

Design of a continuous guard ring and its application to swarm experiments: K Iinuma et al, Rev Sci Instrum, 53 (6), 1982, 845–850

Design of a continuous guard ring and its application to swarm experiments: K Iinuma et al, Rev Sci Instrum, 53 (6), 1982, 845–850

Extraction of volume-produced H − ions from a multicusp source : K N Leung et al, rev Sci Instrum, 54 (1), 1983, 56– 61

Extraction of volume-produced H − ions from a multicusp source : K N Leung et al, rev Sci Instrum, 54 (1), 1983, 56– 61

Electron beam probe for charge neutralization studies of heavy ion beams: J Shiloh et al, Rev Sci Instrum, 54 (1), 1982, 46–49

Electron beam probe for charge neutralization studies of heavy ion beams: J Shiloh et al, Rev Sci Instrum, 54 (1), 1982, 46–49

New technique for direct measurement of electron temperature: Nobuyuki Kaya, Rev Sci Instrum, 53 (7), 1982, 1049–1052

New technique for direct measurement of electron temperature: Nobuyuki Kaya, Rev Sci Instrum, 53 (7), 1982, 1049–1052

Low-energy ion beam system for materials studies: G C Nelson et al, Rev Sci Instrum, 53 (5), 1982, 610–614

Low-energy ion beam system for materials studies: G C Nelson et al, Rev Sci Instrum, 53 (5), 1982, 610–614