RSI Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

SECTION LISTING

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

Jun 1965

Volume 36, Issue 6, pp. 731-869

Page 1 of 3 Pages Next Page | Jump to Page

Procedures and Apparatus for Zone Purification of the Alkali Halides

R. W. Warren

Rev. Sci. Instrum. 36, 731 (1965); http://dx.doi.org/10.1063/1.1719687 (7 pages) | Cited 11 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A simple apparatus and special techniques are described which have been used to purify and to grow single crystals of KCl and KBr. The measured inpurity content of such crystals is lower than that of commonly used, commercially available crystals by a large factor. Residual impurities have fractional concentrations, in most cases, of less than ten parts per billion. The techniques used, with appropriate modifications, can be employed for the growth of most of the other alkali halides.

Position Transducer for Use at Extreme Environmental Temperatures

Lawrence Fleming

Rev. Sci. Instrum. 36, 737 (1965); http://dx.doi.org/10.1063/1.1719688 (4 pages)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
Considerations are discussed which underlie the choice of operating principles for mechanoelectric transduction in very high temperature environments. An experimental displacement pickup is described which uses a mutual‐inductance principle and functions well at 1100°C.

Proton Magnetometer and Stable Oscillator for Remote Measurement of Strong Magnetic Fields

R. L. Garwin and A. M. Patlach

Rev. Sci. Instrum. 36, 741 (1965); http://dx.doi.org/10.1063/1.1719689 (2 pages) | Cited 4 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A simple apparatus for proton‐resonance magnetic‐field measurement permits remote location of the rf source and indicator. A high stability variable‐frequency oscillator is also described.

Method for Measuring Small Nonlinearities of Electric Characteristics

T. Guldbrandsen, N. I. Meyer, and J. Schjaer‐Jakobsen

Rev. Sci. Instrum. 36, 743 (1965); http://dx.doi.org/10.1063/1.1719690 (4 pages) | Cited 8 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A method is described for measuring very small deviations from linearity in electric characteristics. The measurement is based on the harmonics generated by the nonlinear element when subjected to a sine wave signal. A special bridge circuit is used to balance out the undesired harmonics of the signal generator together with the first harmonic frequency. The set‐up measures the small‐signal value and the first and second derivative with respect to voltage. The detailed circuits are given for measuring nonlinearities in Ohmic and capacitive components. In the Ohmic case, a sensitivity in the measurement of the relative second order nonlinearity of about 5×10−8 is obtained. In the capacitive case, the sensitivity expressed in terms of the minimum measurable values of the derivatives is dC∕dV = 1.5×10−17 F∕V and d2C∕dV2 = 2×10−16 F∕V2.

Arc Image Furnace System for Electrical Conductivity and Thermal Expansion Measurements

Robert C. Folweiler and Philip S. Schaffer

Rev. Sci. Instrum. 36, 747 (1965); http://dx.doi.org/10.1063/1.1719691 (3 pages)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A ``double‐clamshell'' arc image furnace system has been successfully utilized in a practical arrangement for the measurement of thermal expansion and electrical conductivity under a controlled atmosphere. Maximum sample temperature of 2138°K has been achieved by using two 5000 W xenon arc lamps as energy sources. At 1500°K, a temperature gradient of 6°K∕cm was measured along the furnace axis by thermocouples shielded with alumina, but without a sample in position. The thermal conductivity of a sample would reduce the gradient to less than 1°K∕cm.

Stored Program Computer as an Associative Radiation Analyzer

Branko Souček

Rev. Sci. Instrum. 36, 750 (1965); http://dx.doi.org/10.1063/1.1719692 (4 pages)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A system design based on the use of a stored program on‐line computer is presented here. The system is used as an associative radiation analyzer. The channel capacity of the system is 20 bits (one million channel analyzer). The data storage program is based on a threaded list (tree) algorithm. The number of different events which will be measured during a particular experiment can be assigned for each experiment. The count capacity is 4096 counts per channel, but can be extended. Two alternatives are discussed, depending on whether a fast or medium speed computer is used. The mean input rates are 5000 or 1000 events per second alternatively. In both cases the resolution between two events is determined mainly by the analogue‐to‐digital converters used. There is a good flicker‐free display on the CRT. The display can be in map, isometric, or curve form. The display format (grid, unblanking, etc.) as well as the experimental conditions are under typewriter control.

Diaphragm Pressure Transducer

W. I. Honeywell and C. J. Pings

Rev. Sci. Instrum. 36, 754 (1965); http://dx.doi.org/10.1063/1.1719693 (3 pages) | Cited 1 time

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A diaphragm pressure transducer has been developed for the purpose of separating a sample fluid from a hydraulic oil used in a dead weight tester. The diaphragm null position is determined by a commercially available magnetic sensing unit. The null position shifts systematically with absolute pressure, but the shift is reproducible and may be calibrated. With the output scheme utilized, the unit has a sensitivity of 0.00007 atm and a reproducibility of 0.0003 atm. The equipment has been used extensively at pressures up to 70 atm, but as designed should be operable to much higher pressures. The equipment described includes a small injector for refined pressure adjustments.

Cell for Dielectric Measurements on Hygroscopic Materials

A. J. Nanassy

Rev. Sci. Instrum. 36, 756 (1965); http://dx.doi.org/10.1063/1.1719694 (2 pages) | Cited 5 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A cell for the measurement of dielectric parameters of hygroscopic materials over the frequency range from 0 to 100 Mc and at temperatures from −50 to 150°C is described. Provision is made for measurement of humidity inside the cell.

Noise Tests of an Airborne Microwave Refractometer System

M. C. Thompson and W. B. Grant

Rev. Sci. Instrum. 36, 758 (1965); http://dx.doi.org/10.1063/1.1719695 (2 pages)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
An airborne microwave refractometer system was tested to determine its noise spectrum and the distribution of this noise within the system. Samples of atmospheric turbulence spectra are shown from about 180 to 1800 m above ground [about 1800 to 3300 m above msl (mean sea level)]. Total noise in a 0.03–15 cps passband is found to be about 0.04 ppm rms and to be approximately ``white.''

Vacuum System and Cleaving Mechanism for Photoemission Measurement of CdS Single Crystals in the Vacuum Ultraviolet

N. B. Kindig and W. E. Spicer

Rev. Sci. Instrum. 36, 759 (1965); http://dx.doi.org/10.1063/1.1719696 (4 pages) | Cited 8 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
Apparatus and techniques are described for cleaving large (1 cm3) crystals of CdS and for making photoemission quantum yield and energy distribution measurements in the vacuum ultraviolet (hv ≤ 11.8 eV; λ ≥ 1050 Å) and at longer wavelengths. It is found that CdS cleaves only in the (1010) and (1210) planes. The cleaving and measurements are done at pressures of 10−9 Torr or less, in a metal system provided with a VacIon and a titanium sublimation pump. For measurements in the vacuum ultraviolet, the sample chamber is provided with a LiF window and a special face plate which can be attached directly to the output housing of a vacuum monochromator. Measurements have been made for hv ≤ 21.2 eV by mounting the cleaving chamber directly on the output housing of the vacuum monochromator, with no window between the sample and the vacuum monochromator. In this case the cleaving and measurements are carried out at the much higher pressure (10−4 Torr or greater) of the vacuum monochromator.

Servo‐Controlled Measuring Bridge for Semiconductors of High Resistivity

J. H. Fermor and A. Kjekshus

Rev. Sci. Instrum. 36, 763 (1965); http://dx.doi.org/10.1063/1.1719697 (4 pages) | Cited 4 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A servo‐controlled measuring bridge for resistivity and Hall effect measurements on semiconducting materials with specimen resistances of up to 1013 Ω is described.

Pairs of CdS Crystals with Matched Photoresponses

Donald D. Snyder

Rev. Sci. Instrum. 36, 767 (1965); http://dx.doi.org/10.1063/1.1719698 (1 page)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
This paper is a report of a study undertaken to ascertain the feasibility of developing identically photoresponsive CdS crystals for x‐ray monitoring applications. Of the crystals studied nearly one half could be matched into pairs with very nearly identical photoresponse to changes in visible and x‐ray (30 kV) irradiation intensity.

Economical Liquid Helium Cryostat and other Cryogenic Apparatus

J. E. Whitehouse, T. A. Callcott, J. A. Naber, and J. S. Raby

Rev. Sci. Instrum. 36, 768 (1965); http://dx.doi.org/10.1063/1.1719699 (4 pages) | Cited 7 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A liquid helium cryostat which is inexpensive and simple to build is described. Its main features originate from the use of spherical metal floats arranged concentrically to form the body of the vessel. The tailpiece used with the cryostat provides for liquid helium to circulate in the sample holder. A mechanical valve allows the flow of liquid to be interrupted so that temperatures above 4.2°K may be maintained. A typical combination of cryostat and tailpiece has a capacity for 2 liters of liquid helium and will store this charge for nearly 4 days.
A liquid nitrogen vacuum system cold trap and a liquid helium transfer tube are also described. The former also features the use of metal floats in its construction. The transfer tube has a degree of flexibility and a very small outer diameter.

Field Modulation Techniques for Resolution Enhancement in ESR Spectroscopy

Sivert H. Glarum

Rev. Sci. Instrum. 36, 771 (1965); http://dx.doi.org/10.1063/1.1719700 (4 pages) | Cited 14 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
Methods for reducing linewidths in electron spin resonance spectroscopy by 50–70% using complex magnetic field modulation waveforms are described. Results obtained using a field modulation line sharpener are presented to demonstrate the usefulness of such techniques.

Stable, Distributed‐Dynode Electron Multiplier

C. A. Spindt and K. R. Shoulders

Rev. Sci. Instrum. 36, 775 (1965); http://dx.doi.org/10.1063/1.1719701 (5 pages) | Cited 10 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
The development of a high gain, stable electron multiplier is described. The configuration investigated consists of two rectangular, continuous dynodes forming a plane‐parallel channel. Details of strip preparation, film deposition, and experimental performance values are discussed.

New Precision Thermometric Titration Calorimeter

J. J. Christensen, R. M. Izatt, and L. D. Hansen

Rev. Sci. Instrum. 36, 779 (1965); http://dx.doi.org/10.1063/1.1719702 (5 pages) | Cited 26 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A new solution calorimeter is described which combines the thermometric titration techniques with the precision and accuracy of conventional solution calorimetry. The calorimeter through use of a unique design has a low heat leakage, k = 1.1×10−3 min−1, and a short equilibration period, 1–3 sec. Measurements of quantities of heat as small as 4 calories with an accuracy of 0.1% are possible. The heat of ionization of water at zero ionic strength has been determined to be 13.34±0.02 kcal∕mole which is in excellent agreement with the value of 13.34±0.01 kcal∕mole determined by conventional solution calorimetry. The large amount of information obtained from a single run makes this type of calorimeter a valuable addition to the field of solution calorimetry.

Calculation of Spectral Distortion due to Pile‐Up Effect

Raymond Gold

Rev. Sci. Instrum. 36, 784 (1965); http://dx.doi.org/10.1063/1.1719703 (11 pages) | Cited 8 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
The effect of pile‐up distortion in the pulse height spectrum of a detector has been determined in the form of an integral representation. A number of important special cases, which arise in experimental applications, are treated. The integral representations for these cases have been evaluted in regions of experimental interest. Comparisons are given between the present numerical results and other estimates of pile‐up distortion.

Frequency Modulation of Large Cavities

K. B. Rajangam, F. Hai, and K. R. MacKenzie

Rev. Sci. Instrum. 36, 794 (1965); http://dx.doi.org/10.1063/1.1719704 (3 pages)

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A model study is described in which a rotating capacitor is coupled to a large re‐entrant cavity. The size and capacitive loading (∼500 pF) are such as to make modulation by ferrites or broadband amplifiers difficult and expensive. A nominal frequency range of 3 to 1 is achieved with a single‐plate six‐bladed rotor. On a possible fullscale cavity with a range of approximately 9 to 3 Mc, the data are scaled to a voltage of 5 kV peak for rf power requirements of 1 to 4.4 kW.

Equilibration of the Ice‐Water Temperature Standard

Edmond S. Miksch

Rev. Sci. Instrum. 36, 797 (1965); http://dx.doi.org/10.1063/1.1719705 (3 pages) | Cited 5 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A test has been made of the accuracy with which an ice‐water system establishes the equilibrium temperature. A device consisting of a bulb containing ice and water with provision for volumetric measurement is used as a thermometer. This was placed in the re‐entrant well of a chamber similar to those used to establish the triple point. The temperature established by the well chamber was varied by varying the pressure of the water in it. It was found that when the temperature was made to differ from the equilibrium temperature of the thermometer by as little as 3×10−6°C, growth or melting occurred in the thermometer.

Precision (0.1°C) Vacuum Cryostat and Furnace for Mössbauer Experiments

F. Van Der Woude and G. Boom

Rev. Sci. Instrum. 36, 800 (1965); http://dx.doi.org/10.1063/1.1719706 (3 pages) | Cited 12 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
The design of a small vacuum cryostat and furnace for a Mössbauer spectrometer is described. A regulating system for a 0.1°C temperature stability for periods of several days is given.

Technique for Measuring the Absorption Coefficient of a Plasma

W. G. Braun

Rev. Sci. Instrum. 36, 802 (1965); http://dx.doi.org/10.1063/1.1719707 (4 pages) | Cited 7 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
Instrumentation for determining the absorption coefficient in a plasma in the optical wavelength region has been developed for the study of a hydrogen arc discharge. The arc column is scanned with a beam of its own radiation emitted from the central zone which usually displays the highest brightness. The accuracy of the attenuation measurements near the edges of the plasma column is significantly increased over the accuracy obtainable with the double‐path method. The described instrumentation produces a lateral scan of the plasma in digital form suitable for the computation of the spatial distribution of the absorption coefficient.

Proton Beam Technique for Measuring the Ion Density in a Plasma

Donald P. Duclos

Rev. Sci. Instrum. 36, 806 (1965); http://dx.doi.org/10.1063/1.1719708 (4 pages) | Cited 1 time

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A technique is described for obtaining localized measurements of the ion density in a plasma which is not affected by the presence of a magnetic field or the absence of thermodynamic equilibrium. The technique consists basically of exciting the ions with a proton beam and relating the measured absolute intensity of certain spectral lines to the ion density. Three requirements are discussed which must be satisfied in order to apply the method to a particular gas. The technique appears to be well suited to measuring the density of helium ions. The possible sources of error are examined and, for helium plasmas, none of the errors are large provided that the gas pressure is less than 1 mm Hg and the temperature is over 10 000°K. A preliminary experiment is described.

Versatile and Stable Recording Spectrofluorometer for the Measurement of Corrected Spectra

P. Rosen and G. M. Edelman

Rev. Sci. Instrum. 36, 809 (1965); http://dx.doi.org/10.1063/1.1719709 (7 pages) | Cited 12 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
The design and performance of a versatile automatic recording spectrofluorometer are described. The instrument has a modular design and is capable of measuring fluorescence excitation and emission spectra, polarization of fluorescence, and phosphorescence spectra, each as a function of temperature and pH. Both right angle and frontal illumination may be used. A split beam optical system combined with an automatic gain control (AGC) amplifier assures long term stability and freedom from the effects of light source fluctuations. Corrected emission spectra in energy units are obtained automatically by the use of an adjustable function generator (Vernistat). A quantum counter used in conjunction with a second function generator and the AGC amplifier permits recording of true excitation spectra.

Instability of Refractory Metal Thermocouples

B. E. Walker, C. T. Ewing, and R. R. Miller

Rev. Sci. Instrum. 36, 816 (1965); http://dx.doi.org/10.1063/1.1719710 (10 pages) | Cited 4 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
Thermoelectric instabilities of some refractory metal thermocouples have been studied in the temperature range 1000–2000°C under vacuum and neutral atmospheres. The sources of instability were found to be complex, involving contamination from ceramic protection tubes and furnace environments, preferential volatilization, and various thermal anomalies such as recrystallization and phase changes in the refractory thermoelements. Refractory thermocouples and thermoelements were studied under a variety of conditions and emf changes associated with each are reported. Recommendations are presented for the selection and application of these thermocouples to attain maximum thermoelectric stability.

Large High Field Superconducting Magnet System

C. Laverick and G. Lobell

Rev. Sci. Instrum. 36, 825 (1965); http://dx.doi.org/10.1063/1.1719711 (6 pages) | Cited 9 times

Online Publication Date: 29 December 2004

Full Text: | Download PDF

Show Abstract
A superconducting magnet system composed of three separate, easily removable, nested solenoids is described. The outer two solenoids are split coil systems so that particle beams can be directed through the magnet when these sections are used to provide the magnetic field for a helium bubble chamber. Magnetic fields of 67, 42, and 17 kG have been achieved in winding diameters of 17.8, 27.9, and 45.7 cm, respectively. The results indicate that the system is capable of operation at fields in excess of 70 kG. The magnet is wound from various types of superconducting cable. Some of the considerations governing the choice of cable types and magnet design are given. A description of the tests is given, and the test results are discussed.
Page 1 of 3 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close