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This paper describes the design and construction of a low-frequency line impedance stabilization network with reliable stabilizing properties and high-power handling capacity, usuable from 15 kc to 10 Mc. The design was initiated to meet the need to investigate low-frequency conducted radio interference. Its design, characteristics, construction, and operation are discussed.

A study has been made of superelasticity and the strain-memory effect in Cu−Al−Ni alloys in the composition range 14 wt pct Al and 2 to 3 wt pct Ni. These alloys have a bcc structure on quenching and show a low temperature martensitic transformation which is responsible for both the superelastic and strain-memory effects. Tests on both single and polycrystalline specimens showed that the maximum superelasticity occurred close toA s. At higher temperatures the effect gradually decreased, whilst at lower temperatures it decreased very quickly. The magnitude of the effect was large in single crystal specimens (>5.8 pct), but small in polycrystal specimens (

Two line impedance stabilization networks — a single unit and a dual unit-for the measurement of conducted radio interference have been redesigned from the present line impedance stabilization network to yield a smooth repeatable response up to 100 megacycles.

A virus is associated with a strain of transovarially-transmitted SR-spirochetes, NSR, of Drosophila . This virus, designated spv-1, is able to infect and to multiply in another strain of SR-spirochetes, WSR, thereby eliminating the SR condition from the host flies. Spv-1 contains DNA, has a buoyant density of 1.480 in CsCl, and is spherical in shape, measuring 50-60 nm in diameter.

The magnetic susceptibility from 1.9 to 300°K of the stable radical 1-(4-methoxyphenyl)-3,5-diphenyl-verdazyl has been measured. The temperature dependence of the susceptibility is fitted better by the linear Heisenberg model than by the linear Ising model. The exchange interaction energy along the chain is estimated to be −7.3°K.