摘要:

Some substances , for example iron and nickel, show a rather complicated magnetic behavior at room temperature. When placed in a magnetic field they show a magnetic moment which not only is a function of field and temperature, but which also depends on the history of the specimen; that is, it depends on the fields and temperatures in which the substance has been before. These materials are called ferromagnetics. One characteristic property is the occurrence of remanent magnetism, i.e., if the material is taken out of the field the moment does not fall back to zero but it goes to a certain value also determined by the history.

ISSN:0031-9228    

DOI:10.1063/1.3061161

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

The operational and engineering problems encountered in acquiring and maintaining air supremacy are manifold. Not the least of these problems concerns the behavior, characteristics, and properties of the atmosphere and the related phenomena of the lithosphere and the hydrosphere which directly or indirectly influence the atmosphere, the medium in which the Air Force operates. As part of the Air Research and Development Command, the Geophysics Research Directorate of the Air Force Cambridge Research Center carries on a major portion of the investigation being conducted today to increase our knowledge of such geophysical phenomena as are pertinent to air operating techniques and procedures. The fruits of this research contribute not only to new concepts of air warfare and to the over‐all effectiveness of the United States Air Force, but also to the national economy through application of results to civil aviation, agriculture, hydroelectricity, and flood control.

ISSN:0031-9228    

DOI:10.1063/1.3061131

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

The progress physics has recently made as a field of employment, as well as a field of inquiry, is well known to the readers of this journal. During the present century, the science has grown at an ever‐increasing pace. Since World War II, its growth has been more rapid than that of any other major branch of the natural sciences.

ISSN:0031-9228    

DOI:10.1063/1.3061132

出版商:AIP    

年代:1953

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3061133

出版商:AIP    

年代:1953

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3061136

出版商:AIP    

年代:1953

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3061138

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

One of Mr. Truman's last official acts as President of the United States was to transmit to Congress on January 16th the second annual report of the National Science Foundation, which had been submitted by NSF Director Alan T. Waterman in review of the Foundation's work during the 1952 fiscal year.

ISSN:0031-9228    

DOI:10.1063/1.3061141

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

The following statement was approved by the Council of the American Physical Society at its meeting in St. Louis, Missouri, on November 28, 1952.

ISSN:0031-9228    

DOI:10.1063/1.3061142

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

In reviewing some of the outstanding contributions to applied science made during the past fifty years as a result of the programs in basic research of the Carnegie Institution of Washington, Vannevar Bush, president of the Institution, had some things to say about the difference between fundamental and applied research in his annual report for 1952, released last December.

ISSN:0031-9228    

DOI:10.1063/1.3061145

出版商:AIP    

年代:1953

数据来源: AIP

摘要:

Detailed plans for the Summer School on Semiconductors and Transistor Electronics to be held at the University of Illinois (Urbana) are nearing completion, according to John Bardeen, professor of physics at the university, who is chairman of the arrangements committee.

ISSN:0031-9228    

DOI:10.1063/1.3061146

出版商:AIP    

年代:1953

数据来源: AIP