ISSN:0031-9228    

DOI:10.1063/1.2913810

出版商:AIP    

年代:1980

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2913782

出版商:AIP    

年代:1980

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2913783

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Two ideas advanced in recent years for improving the confinement of plasmas in mirror machines have added much to the promise of such devices as potential fusion‐power reactors. In an experiment just completed at Livermore, the tandem‐mirror configuration, first suggested in 1976, appears to have passed its first major experimental test with colors flying.1The more recently proposed thermal‐barrier idea, which is expected to strengthen the confinement capabilities of the tandem configuration, will undergo its first experimental trial next year at this same, Tandem Mirror Experimental Facility (TMX).

ISSN:0031-9228    

DOI:10.1063/1.2913784

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

In its first year of operation, the Cornell electron–positron storage ring, CESR, has provided strong evidence for the existence of a fifth quark flavor. The three narrow upsilon mesonic states near 10 GeV, first seen at Fermilab in 1977 and 1978, had offered the initial experimental evidence for a hadronic building block heavier than the charmed quark (seePHYSICS TODAY, October 1977, page 17 and January 1979, page 17). The &Ggr;,&Ggr;′and&Ggr;″were generally believed to be bound states of a massive new “bottom” quark, b, and its antiparticle.

ISSN:0031-9228    

DOI:10.1063/1.2913785

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

The rapidly increasing complexity of microelectronic circuits is confronting the designers and manufacturers of integrated circuitry with new technological difficulties. By the end of the decade it may well be possible to pack a million logic gates onto a single chip. But the yield of defect‐free chips falls rapidly with increasing number of components. With current lithographic techniques, the production of custom circuits in small numbers is often uneconomical, and it is widely felt that the semiconductor industry is not meeting the need for such circuits. Furthermore, these lithographic procedures cannot produce large‐area integrated circuits bigger than a few square inches, and their slow turnaround time hinders the design testing necessitated by increasing miniaturization.

ISSN:0031-9228    

DOI:10.1063/1.2913786

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

Concert‐hall acoustics are governed by the meshing of two sets of problems: on the one hand the physical problems of wave propagation and attenuation in irregularly bounded spaces and, on the other hand, the psychological problems of how the human listener perceives the sounds impinging on his ears and what heprefersto hear.

ISSN:0031-9228    

DOI:10.1063/1.2913787

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

For solid‐state physicists and engineers the “ultimate in miniaturization” would be to produce devices with structures that are about 8 or 10 nm across—about a tenth of the smallest scale that can currently be produced. (SeePHYSICS TODAY, November 1979, page 25.) Biological systems, however, have, in a sense, solved the problems associated with such small microstructures. The fundamental unit of many cell functions, the lipid bilayer membrane (figure 1), is 4 nm thick; in regions where the membrane carries proteins it may be as much as 10 nm thick. Other elements of the cell, such as the microtubules that provide its structural framework, have similar dimensions.

ISSN:0031-9228    

DOI:10.1063/1.2913788

出版商:AIP    

年代:1980

数据来源: AIP

摘要:

As electronic systems—and especially computers—are used more and more widely in almost all areas of endeavor and daily life, the semiconductor technology on which they are based is being pushed to ever larger‐scale integration and ever greater miniaturization. As the devices get smaller, and smaller, new problems (and maybe new opportunities) appear.1

ISSN:0031-9228    

DOI:10.1063/1.2913789

出版商:AIP    

年代:1980

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2913790

出版商:AIP    

年代:1980

数据来源: AIP