ISSN:0031-9228    

DOI:10.1063/1.2810269

出版商:AIP    

年代:1991

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2810271

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Ultralarge‐scale integrated circuits are patterned by optical lithography, which can now imprint linewidths narrower than 0.8 micron in commercial production. With some promising innovations, optical lithography may be able to push its limiting linewidths below 0.25 microns, narrow enough to produce the next two generations of circuits—16‐Mbit and 64‐Mbit dynamic random‐access memory chips. To cram still more electronic features onto a given area, as is envisioned for the manufacture of chips with 256 Mbits or more, will probably require wavelengths typical of soft x rays rather than visible or ultraviolet light. Thus for nearly 20 years researchers have been developing the sources, masks, aligners, resists and other components of x‐ray lithographic systems.

ISSN:0031-9228    

DOI:10.1063/1.2810272

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The construction of Gammasphere, an important new photon detector for nuclear physics, began last month at the Lawrence Berkeley Laboratory. The principal purpose of this $20 million spherical array of germanium and bismuth germanate crystals will be to measure simultaneously the energies of as many as half a dozen gammas from the step‐by‐step deexcitation of a single excited nucleus.

ISSN:0031-9228    

DOI:10.1063/1.2810273

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Ambitious attempts to obtain a unified description of all the interactions of nature have so far been more notable for their ingenuity, beauty andchutzpahthan for any help they have afforded toward understanding concrete facts about the physical world. In this article we wish to describe one shining exception: how ideas about the unification of the strong, weak and electromagnetic interactions lead to concrete, quantitative predictions about the relative strengths of these interactions.

ISSN:0031-9228    

DOI:10.1063/1.881292

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Quantum mechanics works exceedingly well in all practical applications. No example of conflict between its predictions and experiment is known. Without quantum physics we could not explain the behavior of solids, the structure and function of DNA, the color of the stars, the action of lasers or the properties of superfluids. Yet well over half a century after its inception, the debate about the relation of quantum mechanics to the familiar physical world continues. How can a theory that can account ith precision for everything we can measure still be deemed lacking?

ISSN:0031-9228    

DOI:10.1063/1.881293

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Pour yourself a glass of beer and look closely at the rising bubbles. Careful examination shows that they are seldom distributed uniformly throughout the liquid. Instead, streams of bubbles appear to rise from certain spots on the surface of the glass. Closer inspection reveals that the bubbles rapidly grow in size as they ascend, the volume of each bubble often doubling or more by the time it reaches the top of the glass. In addition, the speed of the bubbles increases as they travel upward.

ISSN:0031-9228    

DOI:10.1063/1.881294

出版商:AIP    

年代:1991

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2810274

出版商:AIP    

年代:1991

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2810275

出版商:AIP    

年代:1991

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2810277

出版商:AIP    

年代:1991

数据来源: AIP