ISSN:0031-9228    

DOI:10.1063/1.3069099

出版商:AIP    

年代:1975

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3069100

出版商:AIP    

年代:1975

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3069102

出版商:AIP    

年代:1975

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3069104

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Thanks to teams at two laboratories, that textbook abstraction of quantum mechanics, the one‐dimensional square well, has become realized in a physical object. Known as a “heterostructure,” this object consists of accurately deposited thin layers of two different semiconductors of matching lattice constants. When these man‐made square wells are built up into stacks of 10–100 periods, they constitute essentially an infinite configuration (because of the finite mean free path of the carriers) known as a “superlattice” (PHYSICS TODAY, August 1973, page 20). These structures open the possibility of creating quantum states with predetermined energy levels and bandwidths.

ISSN:0031-9228    

DOI:10.1063/1.3069106

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Even though there have been offshore and deep‐sea drilling projects in recent years, a comprehensive continental drilling program in the United States has not been started. The Carnegie Institution (Washington, D.C.) has just released a report that includes recommendations for such a program, to last ten years and cost over $110 million.

ISSN:0031-9228    

DOI:10.1063/1.3069107

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

A satellite launched in May and a new observatory at Kitt Peak, Arizona will provide astrophysicists with a dual means to observe x‐ray sources. The satellite is Explorer 52, the third in the NASA Small Astronomy Satellite series; it has four experiments that make up a research package developed at MIT's Center for Space Research. The package includes▸ a galactic absorption experiment, to monitor the absorption of low‐energy diffuse x‐ray background interstellar matter in the galaxy,▸ a Scorpio monitor experiment, to view the time variations of x‐ray activity in the x‐ray source Sco X‐1,▸ a galactic monitor experiment, to help locate x‐ray sources in the Milky Way to a precision of 15 arcsec and▸ an extra‐galactic experiment, which will monitor weak x‐ray sources outside our galaxy.

ISSN:0031-9228    

DOI:10.1063/1.3069108

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

Energy, it is becoming increasingly clear, is a precious commodity. Efforts are underway worldwide to seek new energy sources, to extend and conserve existing sources, and to educate consumers toward more intelligent use of the sources we have. We of this APS Study Group have been looking into the special contributions physics can make in the particular area of conservation by improved efficiency of energy‐consuming devices. Here we present a brief summary of our report (see box on page 24). We have limited ourselves almost entirely to an analysis of thetechnicalcomponents of energy use,1rather than the regulatory, economic and persuasive tools that may be brought to bear on energy conservation2; our intention is to point out areas where scientists and engineers may contribute to the invention or improvement of the technical structure of the energy economy so as to provide new options, new opportunities and a more flexible basis for choice. (A listing of selected research opportunities appears on pages 32–33.)

ISSN:0031-9228    

DOI:10.1063/1.3069109

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

In France, around 1780, many Parisians believed in curing their illnesses by magnetism. To perform this cure, they sat in a group around a tub containing “mesmerized” water and iron filings; this was part of the cult introduced to Paris by Dr Franz Mesmer. He proclaimed that animal magnetism of the human body controlled the flow of a universal fluid through the body and that illness resulted when there was an obstacle to that flow. The illness would be cured by magnetically redirecting the fluid with arrangements such as the filings and water.

ISSN:0031-9228    

DOI:10.1063/1.3069110

出版商:AIP    

年代:1975

数据来源: AIP

摘要:

For the American Institute of Physics, 1974 was a year in which great effort was concentrated on service operations—those connected with subscription fulfillment and data processing, with fiscal reporting and with publishing. The Governing Board, several of its committees, and outside consultants all provided input to the AIP staff to bring about changes that would give physicists and the physics societies improved essential services. On the whole, AIP services by the close of 1974 were on a sound basis.

ISSN:0031-9228    

DOI:10.1063/1.3069111

出版商:AIP    

年代:1975

数据来源: AIP