ISSN:0034-6748    

DOI:10.1063/1.1751815

出版商:AIP    

年代:1934

数据来源: AIP

摘要:

Several types of large ultraviolet monochromatic illuminator are described, in which water or other transparent liquid is used as the dispersing medium. The most readily made consists merely of a spherical concave mirror immersed in a basin of distilled water at an angle of about 30° from the horizontal; this acts as a crude prism somewhat on the principle of the Fe´ry quartz prism, and gives monochromatic though distorted images of a high power horizontal mercury arc used as a source. By placing an exit slit of suitable shape in the focal plane these images can be isolated one at a time, giving surprisingly pure monochromatic radiation. Such an instrument of large size can be constructed at small expense and should be useful for many types of biophysical and photochemical work. A somewhat more expensive but more distortion‐free instrument can be made by using a plane mirror under water with one or two large lenses of fused quartz. The horizontal position of the input face of the water prism greatly reduces convection currents, and renders large sheets of expensive optical material unnecessary. Instruments of both types with aluminum, chromium and platinum‐coated glass mirrors over eight inches in diameter have been constructed and found to operate satisfactorily. Typical spectrum photographs taken with one of the concave mirror instruments show the degree of spectrum resolution obtained.

ISSN:0034-6748    

DOI:10.1063/1.1751816

出版商:AIP    

年代:1934

数据来源: AIP

摘要:

The adiabatic heat produced in a sound field up to frequencies of 5000 cycles has been measured with a thermocouple. Similar thermocouples have been used to measure small intensities of radiation. The response of these sensitive couples depends upon the use of thin films of metal and the use of a.c. amplification. The couples have been made by cathodic sputtering of bismuth, antimony and tellurium on thin cellulose. A detailed account of their construction is presented.

ISSN:0034-6748    

DOI:10.1063/1.1751817

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751818

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751819

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751820

出版商:AIP    

年代:1934

数据来源: AIP