ISSN:0034-6748    

DOI:10.1063/1.1770287

出版商:AIP    

年代:1945

数据来源: AIP

摘要:

With the construction of larger BF3‐tubes for use in cosmic‐ray neutron research, the conventional tube construction making use of a brass cylinder enclosed with co‐axial wire in a glass envelope becomes cumbersome owing to the large weight of the cylinder. A new method of construction, making use of the evaporation of copper in vacuum is described. Some of the characteristics of the new tubes are given together with an estimate of the time of discharge.

ISSN:0034-6748    

DOI:10.1063/1.1770288

出版商:AIP    

年代:1945

数据来源: AIP

摘要:

A new technique has been developed for locating air leaks in vacuum devices. It employs a sealed‐off, highly evacuated ionization gauge having a section of its envelope made of thin palladium sheet which, when heated, is highly permeable to hydrogen. In use the gauge is connected to the manifold of a vacuum system with the palladium section isolating the vacuum of the gauge from that of the manifold. When the manifold or any vacuum device connected to it is probed with hydrogen, leaks in the system are indicated by an increase in the ion current of the gauge. This new technique, because it utilizes a sealed‐off, highly evacuated gauge which responds only to hydrogen and is unaffected by other residual gases and vapors, provides a simple but sensitive test for very small leaks.

ISSN:0034-6748    

DOI:10.1063/1.1770289

出版商:AIP    

年代:1945

数据来源: AIP

摘要:

The value of a magnetic field at a point is equal to the volume average of the field over the interior of any sphere centered at the point and not containing any sources of the field. It is therefore possible to wind a coil on the surface of a sphere in such a way that the flux through the coil is proportional to the field at a point even though the field varies over the region occupied by the coil. By combining concentric windings of this type one obtains a solid spherical winding equivalent to a series of coaxial cylindrical windings of different lengths but of equal and constant axial turn spacing, and therefore not difficult to wind. Design formulas are derived and construction procedures described.

ISSN:0034-6748    

DOI:10.1063/1.1770290

出版商:AIP    

年代:1945

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1770292

出版商:AIP    

年代:1945

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1770293

出版商:AIP    

年代:1945

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1770294

出版商:AIP    

年代:1945

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1770296

出版商:AIP    

年代:1945

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1770297

出版商:AIP    

年代:1945

数据来源: AIP