摘要:

As a result of the processes of manufacture of tubes having oxide cathodes, high resistance layers often exist in the cathode and tube elements. This can produce anomalous retarding potential characteristics such as, for example, an apparently high electron temperature in diodes. By accounting for the effect of these resistances the apparent anomalies can be explained. Also given are the conditions required to minimize these errors and a method for evaluating the sum of these resistances.

ISSN:0021-8979    

DOI:10.1063/1.1721541

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

A rigorous solution of Maxwell's equations is carried through for the case of a rectangular magnetization curve. Formulas for the depth of penetration and the wave impedance are derived yielding a theoretical power input formula which relates to the popular quasi‐theoretical formula of Rosenberg by just the factor 4/&pgr;.

ISSN:0021-8979    

DOI:10.1063/1.1721542

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

A mathematical study utilizing the statistics of noise theory is presented which derives light spot brightness probabilities for PPI target returns of various signal‐to‐noise ratios. An idealized model is employed which differs from similar previous ones by taking account of the cathode‐ray tube's highlight brightnessvsintensifier electrode voltage characteristic. For the 10KP7 cathode‐ray tube this characteristic obeys an approximate 2.5 power law in typical operation. This law, together with a square law second detector, combine to form an over‐all fifth power detector. The light spot brightness of the display is assumed to be formed by linear superposition of individual target returns resulting from the radar antenna scan. In the model, seven identical returns are so integrated.Various mathematical methods of handling the problem are considered. The Edgeworth series approximation is found to give poor results compared with the Laguerre polynomial approximation. By the latter method the light brightness probabilities are found to be obtainable by interpolation from a table of the incomplete gamma function. Ancillary tables of statistical moments and selected values of the confluent hypergeometric function,1F1(−5n/2; 1; −x), are included in the text.

ISSN:0021-8979    

DOI:10.1063/1.1721543

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

A new procedure for rigorously deducing the energy distribution of states, formulated upon a direct summing of cells inkspace, provides a sound basis for assessing the classical approximation so familiar in statistical mechanics. It is thus established that the latter approach underestimates the density of states to the extent that the conventional Fermi energy calculation for electrons in metals is a few percent too high.

ISSN:0021-8979    

DOI:10.1063/1.1721544

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

This paper presents a theory of focusing long cylindrical electron streams by means of electric fields which vary periodically along the stream. The use of a bifilar helix or a series of annular rings to produce periodic electric fields is considered.The potential distribution at the position of the electrons is expanded in a power series, and an equation of electron motion is written. The solutions obtained indicate that the flow of electrons is essentially parallel, provided that the electrons enter the focusing structure practically without transverse velocities and are distributed across the stream such that the space charge fields decrease radially toward the axis in a manner similar to that of the periodic electric fields.The method of periodic electrostatic focusing is of particular interest in connection with traveling wave tubes. The possibility of using a bifilar helix as both the slow wave and the focusing structure is discussed.

ISSN:0021-8979    

DOI:10.1063/1.1721545

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

Calculations of pressure and production histories are presented for one‐dimensional flow of non‐ideal gases through porous media. The non‐ideal properties considered in this paper are the gas viscosity and deviation factor (compressibility factor) which are assumed to vary as simple functions of pressure. The effect of each of these parameters is investigated independently as well as in combination. The results demonstrate that pressure declines and production histories in linear gas‐flow systems are markedly influenced by variations in these parameters. Numerical solutions of the flow equations were obtained by solving the corresponding difference equations on an electronic digital computer.

ISSN:0021-8979    

DOI:10.1063/1.1721546

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

A solution for the density of minority carriers is obtained for a semiconductor device having a two‐dimensional rectangular geometry and a transverse field. The solution is developed for a variety of boundary conditions and the current‐gain factor &agr; of the corresponding semiconductor devices is obtained from this solution.

ISSN:0021-8979    

DOI:10.1063/1.1721547

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

Dielectric amplifiers with high‐input impedance and low‐output impedance have high power gain and slow response. Analyses of two basic types of dielectric amplifier circuits, i.e., parallel and series, are given here. Both steady‐state and transient responses are studied.

ISSN:0021-8979    

DOI:10.1063/1.1721548

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

The evaluation of certain integrals is attained by use of ordinary linear differential equations having inputs that depend on the Dirac delta function. The method is illustrated by several examples.

ISSN:0021-8979    

DOI:10.1063/1.1721549

出版商:AIP    

年代:1954

数据来源: AIP

摘要:

A method for obtaining experimental compression wave velocities in metals is described. Measurements of the compression wave velocity in copper were made and found to be in good agreement with theoretical predictions. It is suggested that the discrepancy between the velocity (4730 m/sec) reported herein and that reported by Rinehart and Pearson (3600 m/sec) is associated with the different geometries of the two sets of experiments.

ISSN:0021-8979    

DOI:10.1063/1.1721550

出版商:AIP    

年代:1954

数据来源: AIP