Proposed Building Blocks Research Articles

Systematic realisation of binary and multivalued logic functions using charge coupled building blocks

The suitability of basic CCD gates for the synthesis and realisation of binary and multivalued logic (MVL) functions is now investigated. Systematic design methods for these functions are presented using the proposed building blocks. Characterisation of functions in terms of the type of CCD gates required for their implementation is introduced and used to introduce two functionally complete sets of operations in the charge domain. Use of these operations in the realisation of binary functions is explained and illustrative examples are given. Realisation of some important binary and MVL circuits is also presented. A high-level (macro-cell-like) synthesis approach is proposed for the realisation of functions using CCD building blocks. It does not address circuit-level problems such as charge level degradation, delay synchronisation, layout constraints, etc. Remedies for these problems, using, for example, charge regeneration, charge-to-voltage conversion, etc., may change the cost set up for individual blocks. However, they do not influence the synthesis approaches presented.

Structural investigations of aquatic humic substances by pyrolysis-field ionization mass spectrometry and pyrolysis-gas chromatography/mass spectrometry

The present state-of-the-art in structural investigations of aquatic humic substances and their fractions such as fulvic and humic acids by pyrolysis-field ionization mass spectrometry is outlined. An integrated approach to interpretation uses complementary data of elemental analysis, functional group determinations, Cu 2+-complexation, H +-capacity and results from u.v.-vis- and FT-i.r.-spectroscopy. Proposed building blocks of the molecular structure are supported by chromatographic investigations using Curie-point Py-GC/MS and the available literature reports. The potential and limitation of the applied methodology are discussed.

Design of parasitic-insensitive four-phase wave SC filters

Design of four-phase wave SC filters using modular building blocks is presented. The proposed building blocks and filters are all parasitic-insensitive. The number of operational amplifiers is essentially low in comparison with earlier presented parasitic-insensitive wave SC filters. Since adaptor equations of wave digital filters are realised, the sensitivities to element variations are low. The simulation results are in good agreement with the theory.