Application of Optimization Methods to Solid Phase Analysis of Combustion Gases Desulphurization Products
Abstract The variations in calcium and sulphur concentrations measured along cross-sections of limestone-lime sulphated particles in scanning electron microscope (EDS microanalysis) and the computation of the sum of oxides CaO+SO 3 , ( s ) and the molar ratio CaO/SO 3 , ( r ) are essential to identifying the compounds which could appear. A method of estimating the phase of sulphation limestone/lime products is presented in this paper. The aim of this method is to find such component proportions which minimize the differences between the measured and the calculated values of s and r . The method is developed using the software package CAMOS and enables one to calculate automatically the component proportions for the given system. In the paper the CaS–CaSO 4 –CaO–CaCO 3 and CaS–CaSO 4 –CaO–Ca(OH) 2 systems are considered. Some experimental examples are also shown.
The Use of Optimization Techniques in the Phase Identification of Sulphation Limestone Products
Abstract A new general method has been employed for the solid phase analysis of sulphation limestone products. The variations in calcium and sulphur concentrations measured along cross-sections of limestone sulphated particles in scanning electron microscope (EDS microanalysis) and the computation of sum of oxides CaO + SO3, (s) and the molar ratio CaO SO 3 , (r) are essential to identifying the compounds which could appear. The method of estimating the composition of the system uses an optimization technique, the aim of which is to find such component proportions which minimize the differences between the measured and the calculated values of s and r. The method is developed using a computer program which calculates automatically the component proportions for the given system. In the paper the CaSCaSO4CaOCaCO3 system is considered. Some experimental examples have also been shown.
Submicron polymer structures with X-ray lithography and hot embossing
This article describes the process chain for replication of submicron structures with varying aspect ratios (AR) up to 6 in polymethylmethacrylate (PMMA) by hot embossing to show the capability of the entire LIGA process to fabricate structures with these dimensions. Therefore a 4.7 μm thick layer of MicroChem 950k PMMA A11 resist was spin-coated on a 2.3 μm Ti/TiOx membrane. It was patterned with X-ray lithography at the electron storage ring ANKA (2.5 GeV and λc ≈ 0.4 nm) at a dose of 4 kJ/cm3 using a Si3N4 membrane mask with 2 μm thick gold-absorbers. The samples were developed in GG/BDG and resulted in AR of 6–14. Subsequent nickel plating at 52°C resulted in a 200 μm thick nickel tool of 100 mm diameter, which was used to replicate slit-nozzles and columns in PMMA. Closely packed submicron cavities with AR 6 in the nickel shim were filled to 60% during hot embossing.