ISSN:0031-9228    

DOI:10.1063/1.3066527

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

It seems but natural for physicists to ponder on the dramatic possibilities of using nuclear power to operate a rocket propulsion plant. It is possible, without trespassing on classified information in any way, to reach some interesting and perhaps melancholy conclusions, merely by the use of elementary and well‐disseminated ideas.

ISSN:0031-9228    

DOI:10.1063/1.3066528

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

A personnel officer considering the placement of students had the following jobs to fill: The Mine Safety Appliance Company of Pittsburgh wanted laboratory assistants; a patent attorney in Harrisburg, Pa. wanted a physics major to work in his office; the Quartz Research Project at Antioch College wanted men to operate high pressure, high temperature autoclaves, and the controlling and recording devices that go with them; the Biology Department at MIT wanted an assistant in a research project in biophysics to develop some techniques for spectroscopy under a microscope.

ISSN:0031-9228    

DOI:10.1063/1.3066494

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

If the idea works out well there will be a joint meeting of the Member Societies of the Institute in the year 1951.

ISSN:0031-9228    

DOI:10.1063/1.3066495

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

The introduction by Bohr of Planck's quantum of actionhin atomic theory to explain the stability of atoms and their fixed properties culminated in the discovery of the Uncertainty Principle, or the Principle of Indeterminancy, as it is sometimes called. This principle necessitates a redefinition and generalization of the concept of causality, and in the early days of its discovery caused much confusion and misunderstanding among physicists.

ISSN:0031-9228    

DOI:10.1063/1.3066496

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

In a previous letter I described the slow birth of the Netherlands Foundation for Pure Research. I mentioned that, in spite of the fact that the bill about the foundation has not yet passed Parliament, the provisional council of the foundation has not delayed its activities. The Sub‐Foundation for Research on Matter has been at work for three years.

ISSN:0031-9228    

DOI:10.1063/1.3066497

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

Argonne National Laboratory has recently announced important results in the treatment of radioelement poisoning by metal displacement therapy. The treatment, reported by Jack Schubert of the Laboratory's division of medicine, involves injections of a solution of zirconium citrate given to rats which have received previous injections of significant amounts of radioactive materials such as plutonium and yttrium. The zirconium treatment has resulted in at least three‐fourths of the radioactive materials previously injected into rats being removed within six days. The method has been found to cause a great increase in the urinary excretion of plutonium and yttrium and a large decrease in the amount of these elements deposited in the animal's skeleton.

ISSN:0031-9228    

DOI:10.1063/1.3066500

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

The annual meeting of the American Physical Society's Division of Solid State Physics was held March 10 to 12 in Cleveland at the Case Institute of Technology and Western Reserve University. The division was informally organized in 1943 by six individuals who formed a committee, and acted (in the words of Frederick Seitz, who spoke at the dinner meeting on March 11) “as spokesmen for the field during the somewhat stormy period in which the Society as a whole was attempting to decide whether to remain a one‐celled organism like a Paramecium or to evolve into something more complex like a starfish or a sea anemone.” The division was formulated and authorized in 1947–48. Roman Smoluchowski served as its first chairman during the 1948–49 term. William Shockley is the new chairman, and A. von Hippel (vicechairman) and S. L. Quimby have taken the place of T. A. Read and S. Siegal, the retiring members of the executive committee. The other members of the committee are A. Lawson and R. Smoluchowski.

ISSN:0031-9228    

DOI:10.1063/1.3066504

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

Edwin H. Colpitts, retired vice‐president of Bell Telephone Laboratories and pioneer in the development of long‐distance and transoceanic telephone, died March 6, at the age of seventy‐seven. Best known for having developed the vacuum‐tube oscillator circuit which bears his name, he is remembered as well for his work with magnetic coils, his developments in the application of thermodynamic tubes to long‐distance communication, and his studies of capacity unbalance between adjacent telephone circuits. In 1948 he was awarded the Cresson Medal of the Franklin Institute of Philadelphia in recognition of his scientific achievements. He was a fellow of the American Physical Society and the Acoustical Society of America.

ISSN:0031-9228    

DOI:10.1063/1.3066507

出版商:AIP    

年代:1949

数据来源: AIP

摘要:

When the speed of a gas stream exceeds the local velocity of sound, the changes which take place in the nature of the flow suggest corresponding alterations in the experimental techniques used for studying the associated physical phenomena.

ISSN:0031-9228    

DOI:10.1063/1.3066511

出版商:AIP    

年代:1949

数据来源: AIP