ISSN:0031-9228    

DOI:10.1063/1.2808430

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2808431

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

Two research groups—one in Missouri that specializes in the identification and analysis of extraterrestrial particles, and one in California that has a long history of using laser technology to solve a range of problems—have combined their expertise to confirm the presence of polycyclic aromatic (benzene‐skelton‐containing) hydrocarbon molecules on interplanetary dust particles. Frank Stadermann (now at the Technische Hochschule in Darmstadt, Germany), Patrick Swan and Robert Walker, in work done at the McDonnell Center for the Space Sciences at Washington University, Saint Louis, demonstrated that the particles were indeed extraterrestrial and classified them mineralogically. Then the microprobe two‐step laser mass spectrometer, an instrument built by graduate students Simon Clemett and Claude Maechling in the laboratory of Richard Zare at Stanford University, provided evidence of the complex organic compounds: aromatic hydrocarbons composed of two or more six‐carbon rings, and their alkylated (hydrocarbon‐chain‐containing) derivatives.

ISSN:0031-9228    

DOI:10.1063/1.2808432

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

An increasing number of physicists are investigating nuclear collisions at relativistic energies. (See figure 1.) Accelerators completely devoted to the study of these collisions (such as the Relativistic Heavy Ion Collider at Brookhaven National Laboratory) are under construction. So are hadron colliders (such as the Large Hadron Collider at CERN), which can also be used to accelerate heavy ions. The aim of these projects is to study what happens to nuclear matter at high pressures and temperatures. The expectation is that such experiments will access information that can test important predictions of quantum chromodynamics—for example, a nuclear matter transition from a mixture of quarks and gluons to hadrons, as occurred in the first moments of the universe according to the Big Bang theory.

ISSN:0031-9228    

DOI:10.1063/1.881416

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

Lubkin: In the 1990s physics is under strong pressure to change. Federal policies that have guided America's science and technology enterprise almost continuously since the end of World War II have come under increasingly close scrutiny in Congress, and once more, as in the 1960s, an attempt is being made to direct basic research supported by the government to more relevant and practical ends. American industry, at the same time, has virtually abdicated its support of basic research, thereby leaving the Federal government as the sole guardian of one of the nation's most important responsibilities—that of assuring the benefits of basic research. All this has happened in a period of unexpected and unsettling political, social and economic changes brought about by the end of the cold war and by the country's technological malaise. At a time like this we physicists ought to be wondering how we should reinvent ourselves to remain as robust, creative and productive as we have been in the past half‐century. So I begin with a question: How can universities respond to the changing demands on physicists and the changing market for physicists?

ISSN:0031-9228    

DOI:10.1063/1.881439

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2808433

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2808434

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

The place of physics in our society, in the workplace and in academic institutions is undergoing change, and we physicists need to be agile and responsive to the challenges and opportunities we face. The professional staff at the American Institute of Physics wants to be responsive; for this reason, advisory committees meet regularly to help staff members evaluate and improve their activities.

ISSN:0031-9228    

DOI:10.1063/1.2808435

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2808437

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.2808439

出版商:AIP    

年代:1994

数据来源: AIP