Extraction of Carrier-Free 103Pd from Thin Rhodium Wire Irradiated with a Proton Beam in a U-150 Cyclotron

A procedure was developed for preparing 99.9% pure ¹⁰³Pd by neutron irradiation of a thin rhodium wire in a cyclotron. ¹⁰³Pd was isolated by extraction.     

Replacement metal-gate NMOSFETs with ALD TaN/EP-Cu, PVD Ta, and PVD TaN electrode

This work reports the first replacement (damascene) metal gate NMOSFETs with atomic layer deposition (ALD) TaN/PVD and electroplated Cu as the stacked gate electrode. Transistors with PVD TaN and PVD Ta electrode are also fabricated. Our data show that ALD TaN has the right work function for the N-MOSFETs. The Cu damascene process can reduce the gate resistivity. The ALD process has the advantage of reducing the stress and radiation damage to the gate oxide. The damascene process flow bypasses high temperature steps (>600/spl deg/C)-critical for metal gate and high-k materials.     

Minimizing dioxin and furan emissions during zinc dust recycle by the waelz process

The Waelz process is a classic method for treating steel plant dusts containing zinc and lead. This process makes especially exacting demands on the off-gas cleaning system because, in most cases, the feed material is heavily contaminated with organic and inorganic components. As a result of the thermal treatment of the residues, dioxins and furans are liberated on the raw-gas side, requiring the installation of additional off-gas cleaning systems. Using as examples two Waelz kiln plants, this article describes the primary measures that minimize the formation of dioxins and furans. Formore information, contact K. Mager, Nordag AG, Cologne, Germany; e-mail kmager@bus-ag.de.     

Light-emitting porous silicon

Although porous silicon has been known for more than 35 years, only in 1990 was it recognized that porous silicon shows an increased bandgap and efficient room-temperature photoluminescence in the visible. This paper will give an overview of porous silicon research, with special emphasis on the formation mechanism of microporous silicon in terms of a depletion of holes in the porous region due to quantum confinement and the understanding of the origin of the visible luminescence. The status of research on electroluminescent and other devices based on porous silicon will be discussed, as well as results for other luminescent forms of nanocrystalline silicon.     

Nanofiltration for the Separation of Nonvolatile Products from Solutions Containing Ionic Liquids

Nanofiltration (NF) can be used to isolate nonvolatile compounds from solutions containing ionic liquids (IL). This was shown for the mixtures bromophenol blue/IL and lactose/IL. In both cases the product was rejected while the ionic liquid permeated. Alternatively, the rejection of the ionic liquid is possible as well. Such separations are possible because nanofiltration membranes are selective towards size and charge of the components.     

On the sensitivity of coupled resonator filters without some direct couplings

This paper presents an analysis of the sensitivity of coupled resonator filters in which some direct couplings are missing. The effect of changes in the coupling coefficients and resonant frequencies of the resonators is investigated by directly computing the gradient of the scattering parameters. It is shown that structures that are modular in the input-to-output direction are much less sensitive than those with modularity in the orthogonal direction for the same frequency response.     

Microprocessor controlled FSK/PSK wave modulation: experimentalmodel for a digital communication laboratory

A simple digitally programmable oscillator (DPO) based on a two-integrator loop is described. A simple experimental model for signal processing/generation (e.g., frequency shift keying, amplitude shift keying, phase shift keying/binary phase shift keying) useful in digital communication has been derived from the DPO by employing a microprocessor. The setup can be conveniently utilized for demonstration and experimentation in the communications laboratory. Some test results are included     

Elemental composition of deposits on natural iron oxide catalyst in processing medium-sulfur feed

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 28–30, November–December, 1995.