Fields Of Different Intensities Research Articles

The thermal effect of the superhigh frequency electromagnetic field

Rectal and subcutaneous temperatures were studied in experiments on 170 animals—dogs, cats, rabbits, rats, and frogs—by the method of continuous thermometry in super-high-frequency electromagnetic fields of different intensities. In addition, thermometry was carried out in muscles and brain of rabbits. The survival time of various animals was determined, as well as the temperature increase. The characteristics of heating and cooling were investigated. The temperature curves followed the law of ascending and descending exponentials in heating and cooling, respectively. The heating effect was greatest in the subcutaneous tissue, less in the brain and deep in the muscles of the thigh, and even less in the rectum. The thermal effect, in the super-high-frequency field, depends on the energy flux, the exposure time, and the size and species of the animal. The lower limit of the “thermal conditions” which cause the death of small animals, including cats (lethal effect), is 0.05 watt/cm2. The lower limit of the “thermal conditions”., at which there is no heating effect on tissues, is 0.01 watt/cm2.

Experiments on color vision in mice in relation to the duplicity theory

1. In training experiments with Hering papers three mice gave results indicating color blindness. One specimen confused blue with Hering gray no. 13. Two confused red with gray no. 49; and one gave inconclusive results but seemed not to be able to discriminate between red and a gray slightly darker than no. 49. 2. Similar experiments, with a field of artificial colored light of known wave length opposite a non-colored field of variable intensity, demonstrated that four mice were color blind, for the colors employed, and that one specimen could apparently see color. The last is the same mouse which gave doubtful results with Hering papers.One mouse confused blue with a neutral light field of intensity 2.1 Lux; two were unable to distinguish between green and a non-colored field of intensity 27.2 Lux; and one could not discriminate between red and a neutral intensity of 0.04 Lux. 3. A single specimen succeeded in discriminating between red and a great number of neutral intensities, though often with some difficulty. Also he chose, not according to relative brightness as did the other specimens, but on the basis of a specific characteristic of the red field. The animal's ability to distinguish between two neutral fields of different intensities was not fine enough readily to suggest that the results with red were due alone to brightness discrimination. 4. Examination of preparations of the retinae of the experimental specimens and others has revealed no cones among the rods. 5. The retinae of the apparently color-seeing mouse were abnormal in that all elements were small and underdeveloped. Cones may possibly have been present in a partly differentiated condition but could not be identified. 6. A discussion of the results is made in regard to the duplicity theory.

On the Poulsen Arc and its Theory

The paper deals with an experimental investigation of the Poulsen arc carried out by means of: 1. The ordinary electrical methods of testing, 2. Gehrcke's oscillograph for taking oscillograms of arc voltage, 3. Photographic side views of the arc, 4. Photographs of the arc and craters viewed in a rotating mirror, i. e., crater oscillograms. The chief results of the investigation are: The experimental values of ratio between radio frequency current and the direct current are satisfactorily explained on the basis of the A-theory. This is not the case for the theory based on Barkhausen's simple characteristic. (B-theory.) The maximum voltage across the arc is very much smaller than required by the B-theory. For the normal Poulsen arc, the extinction voltage is almost as high as the ignition voltage. The most suitable intensity of the magnetic field H<R>o</R> is proportional to the density of the gas and to the frequency of the oscillations, approximately proportional to the feeding current and increases linearly with the r.f. resistance. The behavior of the arc in fields of different intensities is investigated.