ISSN:0034-6748    

DOI:10.1063/1.1751465

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

A bridge voltmeter is described in which a duo‐triode is used in place of two separate triodes with a resulting gain in simplicity and compactness.

ISSN:0034-6748    

DOI:10.1063/1.1751466

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751467

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751468

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751469

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

This paper deals with the details of design and operation of air core water‐cooled coils dissipating up to 1700 kilowatts. Four magnets have been built and used. The first is intended primarily for the measurement of the magnetization of any substance at any temperature in fields up to 40,000 gauss. The second was designed to test the desirability of a new type of construction. The third gives fields up to 100,000 gauss uniform within 1 percent in a volume of 25 cc, and is to be used primarily for Zeeman effect and other optical experiments. The fourth can produce fields up to 50,000 gauss uniform within 1 percent in a volume of almost a liter, and is designed primarily for experiments at very low temperatures. The power to operate these magnets is supplied by a motor generator capable of giving 10,000 amperes at 170 volts continuously.

ISSN:0034-6748    

DOI:10.1063/1.1751470

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

The resources of ultrasonic interferometry have been extended by the development of an interferometer of fixed path. In this device a fixed distance is maintained between a piezoelectric resonator and a reflector. Variation of acoustic reaction of the medium between them is secured by a variation of the acoustic wave‐length produced by changes of temperature, pressure or composition, or in liquids and solids by a change in frequency. It is particularly adaptable to the study of the velocity of sound in gases from the lowest temperatures attainable to approximately 500°C and over a pressure range of at least 100 atmospheres because of the elimination of moving parts and packed joints. The method is also applicable, when results are obtained with two precisely known lengths of path, to the measurement of acoustic absorption and reflection coefficients. Results obtained with air and CO2are given.

ISSN:0034-6748    

DOI:10.1063/1.1751471

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

A potentiometric circuit designed for the measurement of small currents is described, together with its application to the measurement of the filament current in a portable optical pyrometer. Its feature is the elimination of several elements from the conventional potentiometer with the advantages of increased portability and simplicity of operation.

ISSN:0034-6748    

DOI:10.1063/1.1751472

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751474

出版商:AIP    

年代:1939

数据来源: AIP