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2,105 records were found.

This presentation describes the variety of government information resources on space warfare and defense produced by U.S. military and government agencies. It also shows how important space has become to U.S. national security and to U.S. and international economic activity.
We present results of measurements of cosmogenic Be-10, Al-26 and Cl-36, and the indigenous (intrinsic) concentrations of the stable elements Be, Al and Cl in 120-200 kyr old corals from Barbados and Puerto Rico. The concentration levels of these radionuclides in the corals lie in the range 10(4) to 10(8) atoms/g. A comparison of the measured nuclide concentrations with those expected to be produced in the corals by nuclear interactions of energetic cosmic radiation shows that (i) the radionuclides Al-26 and Cl-36 are derived from in situ cosmic ray interactions in the corals after their formation, but that (ii) the radionuclide Be-10 owes its provenance in the coralline lattice primarily due to incorporation ...
Single-walled carbon nanotubes (SWNTs) have many exceptional electronic properties. Realizing the full potential of SWNTs in realistic electronic systems requires a scalable approach to device and circuit integration. We report the use of dense, perfectly aligned arrays of long, perfectly linear SWNTs as an effective thin-film semiconductor suitable for integration into transistors and other classes of electronic devices. The large number of SWNTs enable excellent device-level performance characteristics and good device-to-device uniformity, even with SWNTs that are electronically heterogeneous. Measurements on p- and n-channel transistors that involve as many as 2,100 SWNTs reveal device-level mobilities and scaled transconductances approaching 1,000 cm2 V21 s21 and 3,000 Sm21, respectively, and with current outputs of up to 1 A in d...
The extremely high rates of heat transfer obtained by employing microchannels makes them an attractive alternative to conventional methods of heat dissipation, especially in applications related to the cooling of microelectronics. A compilation and analysis of the results from investigations on fluid flow and heat transfer in micro- and mini-channels and microtubes in the literature is presented in this review, with a special emphasis on quantitative experimental results and theoretical predictions. Anomalies and deviations from the behavior expected for conventional channels, both in terms of the frictional and heat transfer characteristics, are discussed.
Near-infrared metamaterials that possess a reconfigurable index of refraction from negative through zero to positive values are presented. Reconfigurability is achieved by cladding thin layers of liquid crystal both as a superstrate and a substrate on an established negative-index metamaterial, and adjusting the permittivity of the liquid crystal. Numerical results show that the index of refraction for the proposed structure can be changed over the range from -1 to +1.8 by tuning the liquid crystal permittivity from 2 to 6 at a wavelength of 1.4 mu m.
With higher education shifting its emphasis from teaching to learning and inputs to outcomes, active learning techniques are gaining prominence. Research has shown that students learn better when they actively engage the course content, rather than passively absorb lecture material. However, many faculty are unsure of how to take advantage of these new techniques to improve the learning outcomes for their students. For one active learning technique, problem-based learning, librarians are well positioned to facilitate its adoption into course curriculum. In order to effect a high-quality problem-based learning experience, a true collaboration of efforts needs to take place between the subject faculty and librarian. In such a synergistic system, information skills are integrated directly into course content, while an engaging active lear...
The USA and China have had a complex relationship since the 1949 establishment of the People’s Republic of China. This relationship has gone from hostility to guarded friendliness to increased tension at the beginning of the new millennium. Recent years have seen the emergence of literature stressing China’s potential emergence as a national security threat to the USA. This article will look at books, government documents, and Internet resources examining the current and possible future national security relationship between these two countries from 1995/1996 to the present. This literature presents US and international perspectives representing a variety of viewpoints on a subject that may have a major impact on international relations during the twenty-first century.
A monograph summarizing the contributions of the School of Consumer and Family Sciences at Purdue University to family well-being. Features an introductory chapter by Dean Dennis Saviano and a chapter by Founding Director of The Center for Families Susan Kontos.
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