ISSN:0034-6748    

DOI:10.1063/1.1752484

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

The article describes an apparatus which may be used for the study of low frequency or noncyclic wave forms. The instrument comprises a short period suspended magnet galvanometer from the mirror of which a beam of light is reflected to a moving phosphorescent screen in the form of a continuous belt. The wave form appears as a bright line on a nonluminous background and remains easily visible for approximately one minute when observed in a dark room. The instrument is especially suitable for the study of electrocardiac impulses.

ISSN:0034-6748    

DOI:10.1063/1.1752503

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

Monochromatic irradiation studies of biological objects usually require a large slit area, high intensity, comparable irradiation conditions at all wave‐lengths, and frequently some provision for treating on a horizontal surface. The present instrument provides for the simultaneous irradiation of seventeen different samples, each covering 100 square millimeters of a horizontal surface with the exception of two which cover 75 mm2each, each sample being exposed to a single wave‐length of the Hg are spectrum. The seventeen wave‐lengths are as follows: 3655, 3341, 3131, 3022, 2967, 2925, 2894, 2804, 2752, 2699, 2652, 2576, 2536, 2483, 2399, 2378 and 2352A. The straight spectral lines are 2×50 mm. The optical system consists of two 60° crystal quartz prisms, Cornu type, 51 mm high and 85 mm length of face; collimator and camera lenses have 70 mm aperture and 418 mm focal length. Exchangeable with the special holder for the biological materials are two other attachments: a photographic film holder and a calibrated traversing slit mechanism designed to carry a thermopile or a photo‐cell. The instrument can be used in either a vertical or a horizontal position.

ISSN:0034-6748    

DOI:10.1063/1.1752504

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752505

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

In an attempt to reduce exposure times for monochromatic x‐ray diffraction patterns of liquids, a Fluorazure intensifying screen has been used, and several tests of the applicability of this method to intensity measurements have been made. The intensifying factor for MoK&agr; radiation varied from 1 for very low intensities or very short exposures, to 13.3 for intermediate intensities, and for CuK&agr; radiation, it varied from 1 to 4. It appears impractical to use this screen when true intensity measurements are necessary. However, by using two ordinary x‐ray films in contact, the exposure time, with Mo radiation, may be reduced to nearly one‐half, and true intensity measurements may be made. With a new type of double emulsion film, true intensities are recorded and exposure times are reduced by a factor of 2.5 for Mo radiation.

ISSN:0034-6748    

DOI:10.1063/1.1752506

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752508

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752509

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1752510

出版商:AIP    

年代:1938

数据来源: AIP