Waveform stability of a traveling high-field domain in a Gunn diode

We assume that a constant voltage is applied across a sample of a Gunn diode of finite length. When a periodic boundary condition is assumed, the dynamical behavior of the electric field within the sample is described by a nonlinear integral-partial differential equation. By using this equation, we can study the waveform stability of a traveling high-field domain of solitary-wave type which plays an essential role in the Gunn effect. We obtain simple criteria which the sample length and the applied voltage must satisfy for the existence and stability of the high-field domain. The stability analysis is carried out by using Liapunov's second method.     

LEED-AES study of the AuSi(100) system

The system Au/Si(100) has been studied using LEED and AES. Au films grow as Au(111) | Si(100) having six azimuthally rotated orientations at low deposition temperatures below 50°C after the formation of intermediate gold suicide layers. Crystalline gold silicide thin layers are formed on the Au(111) film after heat treatment at 100–400°C. Two types of suicide LEED pattern observed seem to have no correlation with crystallographic data reported on quenched alloy films. Heat treatment over 450°C leads to agglomeration of the film, producing a series of Au-induced superstructures. Heat treatment of the Au film over 1000°C regenerates the clean Si surface accompanied with many etch pits.     

Electron-transfer polymers. XXVIII. Synthesis of vinyl hydroquinone derivatives by means of the wittig reaction

The Wittig reaction has been applied to unsubstituted, monomethyl-, 3,6-dimethyl-, and trimethyl-2,5-dimethoxybenzyl chlorides to produce in quantitative to good yields the corresponding vinyl monomers, unsubstituted, monomethyl-, 3,6-dimethyl-, and trimethyl-2,5-dimethoxystyrenes. The reaction is applicable also to 2,5-dimethoxy-4-methylbenzaldehyde, and to O,O′-bis-(methoxymethyl)resorcinol-4-aldehyde to yield the corresponding vinyl monomers. The reaction is particularly suitable with all these compounds because it is run at room temperature or below and gives good to quantitative yields.