The Preparation of High Purity Silicon (3rd Report)

Preparation of Sulfur of High Purity

A mc thod is described for producing sulfur thaL conLains Ie. Lhan 1.3 X lO5 m ole [racLion of li q uid-solu ble, solid-insolubl e impuriLies as dcLermin ed by Lh e fr'eezing point depression . This corr e ponds t.o a purity of 99.999 mole p ercen t . Man y of Lhe impurities, including organic maLLcl', a r(' re moved by o,(ldaLion with s ulfuric and nitric ac ids. The nonvo lati le impuri ties ...

Preparation of High Purity Mullite Ceramics

High-purity preparation of a large DNA dumbbell.

We report on the efficient biochemical synthesis of a large DNA dumbbell starting from a pair of short DNA hairpins with long single-stranded tails of arbitrary sequence. The DNA dumbbell is obtained by enzymatic ligation yielding a 94-bp duplex stem closed at both termini by single-stranded loops of 5 nt. Following ligation, all unligated precursors and monoligated by-products were multiply bi...

Laboratory for preparation of high-purity clinical chemicals.

A laboratory is described for the preparation and analysis of high-purity clinical chemicals. The work area is designed to minimize contact of high-purity materials with the main source of contamination, the chemical operator. We discuss the use of a perforated, curved, anodized aluminum membrane that permits completely free access to the work area and describe the general construction of the l...

Perforated diode neutron detector modules fabricated from high-purity silicon

Compact neutron detectors are being designed and tested for use as low-power real-time personnel dosimeters. The neutron detectors are pin diodes that are mass produced from high-purity Si wafers. Each detector has thousands of circular perforations etched vertically into the device. The perforations are backfilled with LiF to make the pin diodes sensitive to thermal neutrons. The prototype dev...