ISSN:0031-9228    

DOI:10.1063/1.2405452

出版商:AIP    

年代:1900

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.882993

出版商:AIP    

年代:1900

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.882994

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

In the old nursery rhyme, little Jack Horner stuck in his thumb and pulled out a plum. That's more or less what experimenters from the University of California, Berkeley, and the University of Tokyo did recently: They stuck a zinc atom into the copper site of a high‐Tcsuperconductor and extracted a plum of an image using a specially developed scanning tunneling microscope (STM). That image provided dramatic visual confirmation of the d‐wave nature of the electron pairing state in such materials (see the cover of this issue).

ISSN:0031-9228    

DOI:10.1063/1.883014

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

If the world's oceans relied only on molecular diffusion and smooth laminar flow to spread the Sun's heat, they'd consist of a thin Sun‐warmed layer atop a mass of icy water. But other transport mechanisms are at work. In the North Atlantic, for instance, wind‐driven currents push warm water from the Caribbean to the Arctic, where it cools, sinks, and flows back southward. And throughout its journey, the seawater is swirled and agitated by continent‐sized gyres and centimeter‐sized turbulent eddies.

ISSN:0031-9228    

DOI:10.1063/1.883015

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The far‐infrared (FIR) region of the electromagnetic spectrum, covering wavelengths between 10 &mgr;m and 1 mm, contains a wealth of information. In the laboratory, this range includes the vibrational and rotational spectra of molecules and the energy gaps of superconductors. And in astrophysics and cosmology, it is the realm of emissions from the earliest galaxies, which, due to their large redshifts, emit more than half of their energy in submillimeter radiation. Also in this spectral range is radiation from protostellar regions and planets, which are too cool to emit in the visible.

ISSN:0031-9228    

DOI:10.1063/1.883016

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

On 1 January 1801, reckoned by sticklers to be the first day of the 19th century, the Sicilian astronomer Giuseppe Piazzi discovered Ceres, the first of the asteroids. With a diameter of almost 1000 km, Ceres remains by far the largest of the known asteroids. Piazzi was searching the region between the orbits of Mars and Jupiter where Bode's law, an empirical formula of the day, said there ought to be an undiscovered planet.

ISSN:0031-9228    

DOI:10.1063/1.883017

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

For over 5000 years, granular mixing has been a topic of acutely practical concern. Paleolithic cave painters mixed their colors from blends of ochre and animal products; ancient Chinese and Egyptians blended inks and cosmetics from pork soot, crushed pearls, and compounds of lead; Aztec priests prepared drugs from concoctions of herbs and roots; and Michelangelo pigmented the Sistine chapel frescoes with blends including chalk, charcoal, and lead.

ISSN:0031-9228    

DOI:10.1063/1.883018

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Imagine a world in which you could hear not just nearby conversations and the noise of traffic a few blocks away, but also the sound of blasting in a quarry in the next state, the rumblings of an avalanche or volcano a thousand miles away, and the roar of a typhoon halfway around the world. Fortunately, nature has spared our senses from direct exposure to this incessant din. But our relentless quest to extend our senses has yielded instruments that can do just that—and more. Waves of infrasound, sounds at frequencies too low for us to hear, permeate the atmosphere and offer us insights into natural and human‐made events on a global scale.

ISSN:0031-9228    

DOI:10.1063/1.883019

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Carbon atoms can be found in a variety of structures, including the tetrahedra of diamond, the stacked planes of graphite, and the celebrated fullerene spheres and nanotubes. The graphite family alone includes a rich variety of materials, ranging from pencil “lead” to interstellar dust to chimney soot, and from metallurgical coke to activated charcoal for water filtration to lightweight composites for aerospace components—such as the nose cone of the space shuttle, for which carbon composites were chosen because of their high strength at elevated temperatures.

ISSN:0031-9228    

DOI:10.1063/1.883020

出版商:AIP    

年代:1900

数据来源: AIP