1. |
Physics in 1938 |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 377-395
Thomas H. Osgood,
Preview
|
PDF (1488KB)
|
|
ISSN:0034-6748
DOI:10.1063/1.1752373
出版商:AIP
年代:1938
数据来源: AIP
|
2. |
The Associates of the Institute |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 396-396
H. A. B.,
Preview
|
PDF (42KB)
|
|
ISSN:0034-6748
DOI:10.1063/1.1752374
出版商:AIP
年代:1938
数据来源: AIP
|
3. |
Rounding Off Decimal Values |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 397-397
Preview
|
PDF (58KB)
|
|
ISSN:0034-6748
DOI:10.1063/1.1752375
出版商:AIP
年代:1938
数据来源: AIP
|
4. |
Van de Graaff Generator for General Laboratory Use |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 398-403
J. G. Trump,
F. H. Merrill,
F. J. Safford,
Preview
|
PDF (406KB)
|
|
摘要:
An air‐insulated direct‐current electrostatic generator of the Van de Graaff type, characterized by simplicity and low cost and suitable for a wide variety of research applications, is described. The generator, which employs re‐entrant terminals, is capable of 500 kv and produces a short‐circuit current of about 200 microamperes with a single 10″ belt. The manner in which the unit can be extended to higher voltages and currents is indicated, as well as the effect of operation in the presence of CCl4and CCl2F2vapors. The operating principles, design considerations, theory of multiple belts, effect of humidity, problem of surge elimination, and cost are discussed.
ISSN:0034-6748
DOI:10.1063/1.1752376
出版商:AIP
年代:1938
数据来源: AIP
|
5. |
A Recording Spectrograph for the Far Infra‐Red |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 404-413
H. M. Randall,
F. A. Firestone,
Preview
|
PDF (723KB)
|
|
摘要:
This spectrograph records upon sheets of photographic paper 20×30 inches in size, spectra lying in the range between 18&mgr; and 200&mgr;. Of this range, 9&mgr; may be spread over a single record, or as much as 100&mgr; may be covered, depending upon the gratings and the adjustments used. The spectrograph is a vacuum instrument of high resolving power, being capable of separating sharp lines somewhat closer than 0.5 cm−1apart. Detailed drawings of its construction together with several records are shown and described. The recorded galvanometer deflections are usually adjusted to lie between 100 and 300 mm.
ISSN:0034-6748
DOI:10.1063/1.1752377
出版商:AIP
年代:1938
数据来源: AIP
|
6. |
A Tubular Vacuum‐Type Centrifuge |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 413-416
J. W. Beams,
Preview
|
PDF (275KB)
|
|
摘要:
A method of spinning tubular rotors to high speeds in a vacuum is described. The rotors are spun by air‐supported, air‐driven turbines situated below the vacuum chamber. The maximum rotational speed attainable is set only by the bursting strength of the tubular rotor. The material to be centrifuged enters the spinning tube at the top at a continuous rate and is collected in light and heavy fractions at the bottom. The apparatus has been used for centrifuging materials in gaseous, vapor and liquid states.
ISSN:0034-6748
DOI:10.1063/1.1752378
出版商:AIP
年代:1938
数据来源: AIP
|
7. |
A Radiometer‐Type Vacuum Gauge |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 417-420
Arthur E. Lockenvitz,
Preview
|
PDF (221KB)
|
|
摘要:
A radiometer‐type vacuum gauge is described, which is rugged and simple to construct, which can be calibrated from the dimensions of the gauge, and for which the temperature of the moving system does not enter. The gauge, when constructed entirely of metal has a range from 2 dynes per square centimeter to 0.01 dyne per square centimeter. If constructed of glass, the lower limit can be extended to 0.001 dyne per square centimeter or better.
ISSN:0034-6748
DOI:10.1063/1.1752379
出版商:AIP
年代:1938
数据来源: AIP
|
8. |
A Device to Protect Large Vacuum Systems Against Accidental Interruptions of the Mechanical Pump |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 420-421
J. Paul Youtz,
Preview
|
PDF (106KB)
|
|
ISSN:0034-6748
DOI:10.1063/1.1752380
出版商:AIP
年代:1938
数据来源: AIP
|
9. |
Photoelectrically Balanced Recording Potentiometer |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 422-425
C. Owen Fairchild,
V. Lawrence Parsegian,
Preview
|
PDF (270KB)
|
|
摘要:
The problem of stopping a moving light‐beam on the edge of a phototube without any tendency to oscillate or ``hunt,'' and with speed and precision has been solved by a new method and a recording potentiometer is rapidly and accurately balanced. By (1) artificially canceling the generated back e.m.f. of the moving galvanometer thus advancing its return movement from a deflected position, and (2) delaying the grid potential change of a triode amplifier in the photoelectric circuit, galvanometer lag is counteracted and the potentiometer is balanced with an accuracy of a few hundredths of a percent of the range. The total power input to the instrument is about 35 watts and the contact carriage speed is made as high as 10″ in 20 seconds.1The fundamentals of the complete instrument are discussed and equations describing the galvanometer movement are included.
ISSN:0034-6748
DOI:10.1063/1.1752381
出版商:AIP
年代:1938
数据来源: AIP
|
10. |
A Vacuum Furnace for the Production of Single Crystals of Metals and Alloys |
|
Review of Scientific Instruments,
Volume 9,
Issue 12,
1938,
Page 426-427
Foster C. Nix,
Preview
|
PDF (133KB)
|
|
ISSN:0034-6748
DOI:10.1063/1.1752382
出版商:AIP
年代:1938
数据来源: AIP
|