Magnesium alloys have been used in the automotive industry and 3C (computer, communication, and consumer electronics) for many years. Their room temperature properties combined with their low density offer a wide range of applications, especially when processed by High Pressure Die Casting (HPDC). The use of magnesium alloys at higher temperatures is well-studied; special creep resistant alloys...

As a supplemental process of heat treatment, deep cryogenic treatment (DCT) is believed to have favorable effects on the mechanical properties steels. In this study, three different sequences DCT and tempering, including QCTT (Q: quenching, C: DCT, T: tempering), QTC, QTCT, were investigated discover an effective method improve impact toughness fatigue life typical ultrahigh strength steel simu...

Double-aluminized kapton (DAK) is commonly used in multi-layer insulation blankets in cryogenic systems. NASA plans to use individual DAK sheets in lightweight deployable shields for satellites carrying instruments. A set of these shields will reflect away thermal radiation from the sun, the earth, and the instrument's warm side and allow the instrument's cold side to radiate its own heat to de...

WIMP-nucleon cross sections σ ∼ < 10 −9 pb may be probed by ton-scale experiments with low thresholds and background rates ∼ 20 events per year. An array of cryogenic detectors (" CryoArray ") could perform well enough to reach this goal. Sufficient discrimination and background suppression of photons has already been demonstrated. Reduction of neutron backgrounds may be achieved by siting the ...

We use temperature and power-dependent photoluminescence spectroscopy to demonstrate efficient free exciton emission at room temperature in high quality, strongly confining Zn0.5Cd0.5Se/MgxZnyCd1KxKySe quantum wells. Our measurements indicate that at low temperatures (T!50 K), the luminescence is dominated by bound exciton emission. However, free exciton emission becomes dominant at high temper...

A novel approach based on the Poisson spot effect in a conventional optical lithography system is presented for fabricating large-scale ordered ring patterns at low cost, in which the pattern geometries are tuned by controlling the exposure dose and deliberate design of the mask patterns. Following this by cryogenic deep etching, the ring patterns are transferred into Si substrates, resulting i...

This article reports the design, the breadboarding, and the validation of an ultrastable cryogenic sapphire oscillator operated in an autonomous cryocooler. The objective of this project was to demonstrate the feasibility of a frequency stability of 3x10(-15) between 1 and 1000 s for the European Space Agency deep space stations. This represents the lowest fractional frequency instability ever ...

The Cryogenic Dark Matter Search (CDMS) employs Ge and Si detectors to search for WIMPs via their elastic-scattering interactions with nuclei while discriminating against interactions of background particles. CDMS I data, from the Stanford Underground Facility shallow site, give limits on the spin-independent WIMPnucleon elastic-scattering cross-section that exclude unexplored parameter space a...

(Dated: March 12, 2004) The feasibility of creating molecular quantum entanglement in functionalized semiconductor nanostructures is computationally demonstrated. Entangled hole states, localized deep in the semiconductor band gap, are generated by electron-hole pair separation after photoexcitation of molecular surface complexes. The approach is illustrated for model arrays of catechol molecul...