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Aug 1991

Volume 62, Issue 8, pp. 1893-2047

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Laser‐induced fluorescence measurement of a 50‐MeV hydrogen atom beam

R. K. Sander, F. Archuleta, W. Harker, R. Martinez, C. R. Quick, R. Reeder, D. J. Taylor, F. Brumwell, and C. Hummer

Rev. Sci. Instrum. 62, 1893 (1991); http://dx.doi.org/10.1063/1.1142388 (6 pages)

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Laser‐induced fluorescence has been used to measure the velocity, direction, and divergence of a beam of neutral hydrogen atoms traveling at 50 MeV or one‐third the speed of light. The beam was produced by neutralizing a negative hydrogen ion beam in a foil stripper, which generated a fraction of the atoms in the metastable 2s state. These metastables were measured by pumping the 2s to 3p transition with a flashlamp pumped dye laser at 623 nm and detecting fluorescence in the vacuum ultraviolet from the 3p to 1s ground‐state transition.
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07.77.-n Atomic, molecular, and charged-particle sources and detectors
32.50.+d Fluorescence, phosphorescence (including quenching)
32.80.Xx Level crossing and optical pumping

Laser beam alignment devices for ultrashort pulses

D. L. MacFarlane

Rev. Sci. Instrum. 62, 1899 (1991); http://dx.doi.org/10.1063/1.1142389 (5 pages) | Cited 2 times

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We describe two novel devices for optical beam alignment. One allows for a variable angle, fixed position of incidence upon a target. The other allows for a variable position, fixed angle of incidence upon a target. Cascaded together, these devices allow placement of a laser beam upon a sample with arbitrary angle and arbitrary position of incidence. These devices are particularly useful for experiments and applications involving ultrashort pulses since the time of flight through either of these devices is a constant independent of the angle of incidence and position of incidence.
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42.60.-v Laser optical systems: design and operation
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.15.Eq Optical system design

Waveform analysis with optical multichannel detectors: Applications for rapid‐scan spectroscopic ellipsometry

Ilsin An and R. W. Collins

Rev. Sci. Instrum. 62, 1904 (1991); http://dx.doi.org/10.1063/1.1142390 (8 pages) | Cited 21 times

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A unique rapid‐scanning ellipsometer employing a rotating polarizer optical configuration and a multichannel detector for a 1.5–4.5 eV spectral range, has been developed recently for real time studies of film growth and surfaces. This is a new application of the photodiode array‐based optical multichannel detector that entails waveform analysis of the incident irradiance at each photon energy. For accurate ellipsometric spectra {ψ(hν),Δ(hν)}, the raw data in the form of photon counts, integrated over four or more equal sectors of polarizer rotation, must be corrected for systematic errors originating from the detection system. Simple procedures are described to characterize and correct for the most significant errors including detection system nonlinearity, image persistence, and scattered stray light in the spectrograph/detector enclosure.
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07.60.Fs Polarimeters and ellipsometers
68.55.-a Thin film structure and morphology
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors

An instrument for measuring circular dichroism simultaneously at all wavelengths in a limited spectral range

K. Andert, W. Schälike, B. Nölting, R. Pittelkow, R. Wetzel, and G. Snatzke

Rev. Sci. Instrum. 62, 1912 (1991); http://dx.doi.org/10.1063/1.1142391 (4 pages) | Cited 3 times

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An instrument is described for the simultaneous measurement of circular dichroism at all wavelengths in a limited spectral range. A polychromator and a charge‐coupled device (CCD), serving as multichannel sensor, are arranged behind the sample cell, which is located close to the entrance slit, in contrast to the arrangement of a monochromator before the cell and using a photomultiplier as radiation detector, as usual until now. The CCD with low‐noise electronics is driven by the system clock of a microprocessing unit controlled by a quartz oscillator and works fully synchronously with modulation and acquisition cycles. This leads to a high suppression of noise and systematic deviations. An electro‐optic modulator with approximately rectangular excitation voltage is used. Partial CD spectra over the range of 80 nm each down to 200 nm have been recorded. The detection of a smaller amount of substance is possible than with other modern commercial instruments such as a JASCO J‐600, with the same signal‐to‐noise ratio.
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07.60.-j Optical instruments and equipment
87.50.S- Radiofrequency/microwave fields effects
87.50.W- Optical/infrared radiation effects
33.55.+b Optical activity and dichroism

Temperature measurements with micrometer spatial resolution

F. Izaguirre, G. Csanky, and G. F. Hawkins

Rev. Sci. Instrum. 62, 1916 (1991); http://dx.doi.org/10.1063/1.1142392 (5 pages)

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A novel technique has been developed to measure temperatures with a spatial resolution less than 10 μm. This method uses the temperature‐sensitive time decay fluorescence of a phosphor as a surface sensor. The spatial resolution is obtained by using an electron beam to excite individual phosphor grains deposited on the surface of interest. The phosphor selected for its dynamic range and chemical stability is the inorganic compound magnesium fluorogermanate activated with manganese. The time decay constant of its fluorescence decreases monotonically with temperature between −200 °C to 450 °C. This method was verified on a cross‐sectioned Zener diode. A description of the technique and a temperature map of the sectioned area of an operating diode are presented.
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07.20.Dt Thermometers
78.55.-m Photoluminescence, properties and materials

Macintosh/LabVIEW based control and data acquisition system for a single photon counting fluorometer

Wieslaw J. Stryjewski

Rev. Sci. Instrum. 62, 1921 (1991); http://dx.doi.org/10.1063/1.1142393 (5 pages) | Cited 3 times

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A flexible software system has been developed for controlling fluorescence decay measurements using the virtual instrument approach offered by LabVIEW. The time‐correlated single photon counting instrument operates under computer control in both manual and automatic mode. Implementation time was short and the equipment is now easier to use, reducing the training time required for new investigators. It is not difficult to customize the front panel or adapt the program to a different instrument. We found LabVIEW much more convenient to use for this application than traditional, textual computer languages.  
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07.05.-t Computers in experimental physics
07.60.Rd Visible and ultraviolet spectrometers
42.50.Ar Photon statistics and coherence theory

Fluorescence sorting instrument for the removal of aflatoxin from large numbers of peanuts

M. J. Pelletier, W. L. Spetz, and T. R. Aultz

Rev. Sci. Instrum. 62, 1926 (1991); http://dx.doi.org/10.1063/1.1142394 (6 pages) | Cited 2 times

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A device capable of measuring fluorescence intensities from peanut surfaces and physically rejecting peanuts having undesired fluorescence properties is described. The device operates at a feed rate of 22 000 peanut halves per hour. The entire surface of each peanut is examined as 10 to 20 discrete spatial regions. Fluorescence intensities from each spatial region of each peanut are used to make accept/reject decisions in real time and are stored on an optical disk for off‐line analysis.
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07.60.Rd Visible and ultraviolet spectrometers
78.55.Hx Other solid inorganic materials
42.87.-d Optical testing techniques

A new coincidence technique for vacuum ultraviolet photoelectron spectroscopy of neutral clusters in a molecular beam

K. Rademann, T. Rech, B. Kaiser, U. Even, and F. Hensel

Rev. Sci. Instrum. 62, 1932 (1991); http://dx.doi.org/10.1063/1.1142395 (10 pages) | Cited 9 times

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The magnetic bottle photoelectron spectrometer principle has been employed for the study of neutral clusters in a seeded supersonic molecular beam. Mass selectivity is achieved by correlating each detached photoelectron to the cluster cation that is produced simultaneously. The necessary high detection probabilities for both particles, the photoelectron and the cluster ion, are achieved by time‐of‐flight spectrometers for both channels. The collection efficiency of the magnetic photoelectron spectrometer is increased to ≊80% of 4π by combining a permanent ring magnet, which produces an inhomogeneous field to parallelize the electron trajectories, with a 730‐mm‐long coil that guides the electrons by a weak, homogeneous field through the flight tube towards a scintillation detector. An advanced data acquisition electronics is described that is capable of recording and storing simultaneously photoelectron‐photoion coincidence spectra of those neutral clusters that have sufficient intensity in the molecular beam.
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33.60.+q Photoelectron spectra
07.78.+s Electron, positron, and ion microscopes; electron diffractometers
36.40.-c Atomic and molecular clusters

Measurement of vaporized atom flux and velocity in a vacuum using a microbalance

Naohito Uetake, Takashi Asano, and Kazumichi Suzuki

Rev. Sci. Instrum. 62, 1942 (1991); http://dx.doi.org/10.1063/1.1142396 (5 pages) | Cited 13 times

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The flux and velocity of Cu and Ti vaporized by an electron beam were measured by a microbalance. A small disk was hung horizontally above the crucible and its weight change was measured by the microbalance. The flux was determined from the weight change due to vaporized atom deposition under the disk base. The total momentum of deposited atoms per unit time was determined from the weight change before and after the vapor was turned off by a shutter. The velocity could then be calculated from these two values. The velocity obtained for Cu depended slightly on the vaporization temperature and had reasonable agreement with the theoretical estimation obtained using an ideal gas treatment. The velocity of Ti was slightly higher than the theoretical result. Since Ti was excited to several metastable energy levels by electron beam heating, such an internal energy should be converted to kinetic energy following adiabatic expansion and would account for the velocity increase. The internal energy by excitation to the metastable energy levels must be taken into consideration in the case of high temperature heating, as with an electron beam evaporative source.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
06.30.Dr Mass and density

Statistical analysis of interferometer detection systems

Geoffrey I. Opat

Rev. Sci. Instrum. 62, 1947 (1991); http://dx.doi.org/10.1063/1.1142397 (4 pages)

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Interferometers are often used to measure small phase shifts introduced into the paths of recombining beams by some physical influence. An analysis of the associated counting statistics is presented leading to a maximum likelihood prescription for extracting the (small) phase shift. Although presented in the context of neutron interferometry, the results are easily extended to other situations involving particle counting.
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07.60.Ly Interferometers
02.50.-r Probability theory, stochastic processes, and statistics
29.40.-n Radiation detectors

A simple and reliable method of thermoelectic effect spectroscopy for semi‐insulating III‐V semiconductors

Z. C. Huang, K. Xie, and C. R. Wie

Rev. Sci. Instrum. 62, 1951 (1991); http://dx.doi.org/10.1063/1.1142398 (4 pages) | Cited 19 times

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We have developed a simpler and more reliable method of thermoelectric effect spectroscopy (TEES), eliminating the second heater in the technique. We have applied this method to the deep level studies in the semi‐insulating undoped or Cr‐doped GaAs materials and in the GaAs epitaxial layers grown at a low temperature by molecular beam epitaxy. We have found that the electrical contacts made on front and back surfaces of the sample are more reliable for the TEES measurement than both contacts made on the same surface. In this contact arrangement, the temperature difference of about 1–2 K between the back and front surfaces is enough to produce a clear and reliable TEES data, without the need for a second heater. The results obtained by TEES are consistent with the results obtained by photoinduced transient spectroscopy (PITS) and by thermally stimulated current (TSC) measurements. The TEES results clearly distinguish between the electron traps and the hole traps. We discuss the results on the various semi‐insulating GaAs samples and the advantages and limitations of the TEES technique.
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72.20.Pa Thermoelectric and thermomagnetic effects
73.50.Lw Thermoelectric effects
71.55.Eq III-V semiconductors
07.50.-e Electrical and electronic instruments and components

A multipoint correlation method for bulk trap and interface state measurements in MOS structures from capacitance, voltage, and current transients

K. Dmowski, K. Bethge, and Ch. Maurer

Rev. Sci. Instrum. 62, 1955 (1991); http://dx.doi.org/10.1063/1.1142399 (9 pages) | Cited 5 times

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A multipoint correlation method is described to improve the analysis of the energy resolution of bulk traps and interface states in metal‐oxide‐semiconductor structures measured by constant voltage, constant capacitance, and current deep‐level transient spectroscopy. The results obtained for the proposed method are given with those obtained for both Lang’s method and the method utilizing an exponential weighting function.
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73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
07.50.-e Electrical and electronic instruments and components

Operation of a TFTR ion source with a ground potential gas feed into the neutralizer

J. H. Kamperschroer, L. E. Dudek, L. R. Grisham, R. A. Newman, T. E. O’Connor, T. N. Stevenson, A. von Halle, M. D. Williams, and K. E. Wright

Rev. Sci. Instrum. 62, 1964 (1991); http://dx.doi.org/10.1063/1.1142400 (6 pages) | Cited 3 times

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TFTR long pulse ion sources have been operated with gas fed only into the neutralizer. Gas for the plasma generator entered through the accelerator rather than directly into the arc chamber. This modification has been proposed for tritium beam operation to locate control electronics at ground potential and to simplify tritium plumbing. Source operation with this configuration and with the nominal gas system that feeds gas into both the ion source and the center of the neutralizer are compared. Comparison is based upon accelerator grid currents, beam composition, and neutral power delivered to the calorimeter. Charge exchange in the accelerator can be a significant loss mechanism in both systems at high throughput. A suitable operating point with the proposed system was found that requires 30% less gas than used presently. The extracted D+, D+2, and D+3 fractions of the beam were found to be a function of the gas throughput; at similar throughputs, the two gas feed systems produced similar extracted ion fractions. Operation at the proposed gas efficient point results in a small reduction (relative to the old high throughput mode) in the extracted D+ fraction of the beam from 77% to 71%, with concomitant changes in the D+2 fraction from 18% to 26%, and 6% to 3% for D+3. The injected power is unchanged, ∼2.2 MW at 95 kV.
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07.77.-n Atomic, molecular, and charged-particle sources and detectors
52.50.Dg Plasma sources
52.55.Fa Tokamaks, spherical tokamaks

Cylindrically symmetric extractors with space charge dominated flow

Marco Cavenago and Giovanni Bisoffi

Rev. Sci. Instrum. 62, 1970 (1991); http://dx.doi.org/10.1063/1.1142401 (8 pages) | Cited 3 times

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The design of a charged particle extraction system in cylindrical symmetry is discussed in the ideal case when the radial extension of the system is unlimited. A parallel beam equilibrium is derived for a diode case. The ideal shape z(r) of the cylindrically symmetric focusing electrode is determined exactly near the beam edge, that is for r < 2rh, where rh is the beam radius: differently from the planar gun theory, only at the beam edge this profile is at 67.5° angle with the beam axis z; an asymptotic formula, corrected up to the fourth order in r/rh is given for the rest of the focusing electrode, resulting in a 74.17° angle with the beam axis at infinity (r→∞). Numerical simulations performed by a particle tracking code are shown, after briefly discussing a few numerical algorithms used. The code validation with the well‐known Pierce planar gun theory is performed, showing an adequate precision to check whether a beam propagates parallel in a long gap. The ideal focusing electrode exhibits the expected beam parallelism and improves the gun perveance with respect to a simple 67.5° cone.
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07.77.-n Atomic, molecular, and charged-particle sources and detectors
41.75.Ak Positive-ion beams
41.75.Cn Negative-ion beams
41.75.Fr Electron and positron beams

Repetitive two‐stage light gas gun for high‐speed pellet injection

S. K. Combs, C. R. Foust, D. T. Fehling, M. J. Gouge, and S. L. Milora

Rev. Sci. Instrum. 62, 1978 (1991); http://dx.doi.org/10.1063/1.1142402 (12 pages) | Cited 2 times

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A repetitive two‐stage light gas gun for high‐speed pellet injection has been developed at Oak Ridge National Laboratory. In general, applications of the two‐stage light gas gun have been limited to only single shots, with a finite time (at least minutes) needed for recovery and preparation for the next shot. The new device overcomes problems associated with repetitive operation, including rapidly evacuating the propellant gases, reloading the gun breech with a new projectile, returning the piston to its initial position, and refilling the first‐ and second‐stage gas volumes to the appropriate pressure levels. In addition, some components are subjected to and must survive severe operating conditions, which include rapid cycling to high pressures and temperatures (up to thousands of bars and thousands of kelvins) and significant mechanical shocks. Small plastic projectiles (4 mm nominal size) and helium gas have been used in the prototype device, which was equipped with a 1‐m‐long pump tube and a 1‐m‐long gun barrel, to demonstrate repetitive operation (up to 1 Hz) at relatively high pellet velocities (up to 3000 m/s). The highest experimental velocity is twice that available from conventional repeating single‐stage pneumatic injectors that accelerate frozen pellets of hydrogen isotopes and are now used to fuel magnetically confined plasmas for controlled thermonuclear fusion research. Also, the pellet test repetition rate of 1 Hz is relevant for fueling applications on future large fusion research devices. The equipment is described, and experimental results are presented and compared with calculated results from gas dynamics models.
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28.52.Cx Fueling, heating and ignition
52.55.Pi Fusion products effects (e.g., alpha-particles, etc.), fast particle effects
52.75.-d Plasma devices

Equation‐of‐state measurements of low‐density materials

N. C. Holmes

Rev. Sci. Instrum. 62, 1990 (1991); http://dx.doi.org/10.1063/1.1142403 (5 pages) | Cited 9 times

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A precise optical method for determining the velocities of strong shock waves in low‐density materials is described. Using an experiment on a polystyrene (CH) low‐density microcellular material (LDMM), we also describe the analysis of the experimental data. Applications to the studies of other materials will be described.
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64.30.-t Equations of state of specific substances
62.50.-p High-pressure effects in solids and liquids
07.60.-j Optical instruments and equipment
07.35.+k High-pressure apparatus; shock tubes; diamond anvil cells

Rock property assessment using laser‐generated acoustic waves

D. A. Hutchins and R. P. Young

Rev. Sci. Instrum. 62, 1995 (1991); http://dx.doi.org/10.1063/1.1142404 (4 pages)

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A pulsed laser has been used to generate wide bandwidth acoustic pulses in a range of rock samples in the laboratory. A nonresonant piezoelectric transducer was used as the detector. This system can measure longitudinal and shear wave velocities simultaneously, from a single waveform, and can also be used to determine frequency‐dependent attenuation in the MHz region. Values of a quality factor (Q) for longitudinal waves are evaluated.
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43.58.+z Acoustical measurements and instrumentation
91.60.Lj Acoustic properties

Acoustic wave viscometer

M. Hoummady and F. Bastien

Rev. Sci. Instrum. 62, 1999 (1991); http://dx.doi.org/10.1063/1.1142353 (5 pages) | Cited 6 times

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This article presents an acoustic wave viscometer using shear bulk waves excited by interdigital transducers on quartz. The attenuation of acoustic waves at the quartz‐liquid interface is associated with liquid viscosity. Good agreement is found between theoretical results and experiments. The device can be used for viscosity measurements up to 600 cP. For higher viscosity the high‐frequency rigidity modulus must be taken into account.
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47.80.-v Instrumentation and measurement methods in fluid dynamics
43.38.+n Transduction; acoustical devices for the generation and reproduction of sound
68.43.-h Chemisorption/physisorption: adsorbates on surfaces

A spring‐guided micropositioner with linearized subnanometer resolution

Kunitoshi Nishimura

Rev. Sci. Instrum. 62, 2004 (1991); http://dx.doi.org/10.1063/1.1142526 (4 pages) | Cited 4 times

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A micropositioner consisting of flexure pivoted levers with a displacement amplifying mode to enhance displacement sensor sensitivity and a displacement reducing mode to achieve high resolution is described. The micropositioner is actuated by a piezoelectric driving element controlled by a closed‐loop servocircuit, and provides fast response and high repeatability. A successful application to STM is also described.
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06.60.Sx Positioning and alignment; manipulating, remote handling
07.78.+s Electron, positron, and ion microscopes; electron diffractometers
06.30.Bp Spatial dimensions (e.g., position, lengths, volume, angles, and displacements)

A flange‐mounted UHV‐compatible axial fatigue apparatus using a piezoelectric actuator

T. S. Sriram, M. E. Fine, and Y. W. Chung

Rev. Sci. Instrum. 62, 2008 (1991); http://dx.doi.org/10.1063/1.1142354 (3 pages) | Cited 3 times

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The design and construction of a flange‐mounted ultra‐high vacuum compatible fatigue apparatus using a piezoelectric actuator is described. This apparatus is capable of operation under ambient pressures down to 10−9 Torr. Push‐pull fatigue tests can be performed under load, total strain, and plastic strain control at frequencies up to 100 Hz. Control of the fatigue tests and data acquisition are done using standard fatigue control electronics and software.
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07.30.Hd Vacuum testing methods; leak detectors
62.20.M- Structural failure of materials
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure

An apparatus for vapor pressure measurements of organic solids using a computer controlled null‐detector

P. Tobaly

Rev. Sci. Instrum. 62, 2011 (1991); http://dx.doi.org/10.1063/1.1142355 (5 pages) | Cited 4 times

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An apparatus is described for the measurement of vapor pressures of low volatility solids and liquids by a static method in the range 10−2–100 mm Hg and 30 °C–300 °C. The method consists in inserting between the pressure gauge (here a capacitance manometer) and the product to be tested, a membrane that is maintained in equipressure by a suitable control loop. Experimental problems related to this arrangement are discussed. A test of the apparatus with a known product (benzoic acid) has been performed. The results have been found to be in good accordance with data found in the literature.
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07.30.Dz Vacuum gauges
07.05.Bx Computer systems: hardware, operating systems, computer languages, and utilities

An integrated microwave Doppler cinemometer for transport applications

P. Descamps, M. El Bekkali, and J. Vindevoghel

Rev. Sci. Instrum. 62, 2016 (1991); http://dx.doi.org/10.1063/1.1142356 (3 pages)

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In order to automate the driving of terrestrial vehicles it is necessary to know at any time and with the highest accuracy the values of the speed of the vehicle and of the distance covered by the vehicle; it is also necessary to know the direction of the motion relative to the ground. These values must be measured in the real‐time domain and this involves that contactless and very low time‐constant sensors must be used. On the other hand, the applications concerned ask for a miniaturization of the whole measurement system. For these reasons, sensors using the Doppler effect in the microwave range are particularly well convenient to these applications. We developed an X band microwave Doppler cinemometer (MDC) with a printed antenna that is built using microstrip technology.
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06.30.Gv Velocity, acceleration, and rotation
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology
89.40.-a Transportation

Use of a phase‐sensitive detector for measuring magnetic hysteresis loops

Fedor Gömöry

Rev. Sci. Instrum. 62, 2019 (1991); http://dx.doi.org/10.1063/1.1142357 (3 pages) | Cited 7 times

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A method for magnetic hysteresis loop measurement on small samples of high Tc superconductors is described, applicable to other types of magnetic materials as well. It is based on an unusual working regime of the phase‐sensitive detector with a square wave mixer signal and controllable reference phase setting. The main advantages of the method are its sensitivity and the possibility of measuring in a wide frequency range. A drawback of the method is that it is fully correct only in the case of a symmetrical hysteresis loop.
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07.55.-w Magnetic instruments and components
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
74.70.-b Superconducting materials other than cuprates

A system to study the stability of the wires of multiwire proportional chambers exposed to a 10 G time variable force field

N. Ceci, A. Rainò, P. Spinelli, and V. Stagno

Rev. Sci. Instrum. 62, 2022 (1991); http://dx.doi.org/10.1063/1.1142358 (4 pages)

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We report the results of a system to test the behavior of the wires of multiwire proportional chambers (MWPC) exposed for 10 min to a uniform force field of about 10 G strength and variable in time in the frequency range 0–2000 Hz. This acceleration will be present when the chambers, mounted inside a cosmic ray spectrometer, are launched by the Space Shuttle towards the NASA Space Station ‘‘FREEDOM.’’ We have reproduced these conditions in the laboratory by an electronic device and we have found that, after repeated cycles of this treatment, the wire performance remained unchanged. This system can also be used to control the tension of the wires of a MWPC during its normal testing procedure.
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29.40.Cs Gas-filled counters: ionization chambers, proportional, and avalanche counters
07.78.+s Electron, positron, and ion microscopes; electron diffractometers
95.55.-n Astronomical and space-research instrumentation

Improving the accuracy of a quartz crystal microbalance with automatic determination of acoustic impedance ratio

Abdul Wajid

Rev. Sci. Instrum. 62, 2026 (1991); http://dx.doi.org/10.1063/1.1142359 (8 pages) | Cited 6 times

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A new method for automatic determination of acoustic impedance ratio, or z ratio, of a thin solid film deposited upon an AT‐cut quartz crystal is described. The method uses frequency information from two piezoelectrically excitable resonant modes which are not harmonically related. This results in an improvement of accuracy for the quartz crystal microbalance (QCM) technique, requiring no prior knowledge of a material’s z ratio. The method is quite general and requires no adjustable parameter specific to a particular quartz crystal design. Results of extensive testing on wide ranging materials including metals, dielectrics, codeposited alloys, and sequential layers is presented. Excellent agreement is found between the predicted values and the gravimetrically measured mass of deposited films.
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06.30.Dr Mass and density
68.60.Bs Mechanical and acoustical properties
81.70.-q Methods of materials testing and analysis
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