Optimisation experimental results

KL-a and v for the 10 litres/min airflow rate for the 15 litre aeration system was 0.0509 h-1 and 1.3 ms 1. From the experimental results, the microbial growth was not at the optimum stage for the reasons mentioned earlier. Nevertheless, a reduction of around 95% can be achieved for carbohydrate reduction. However, further studies should be earned out for optimisation of the treatment and to improve COD reduction for pharmaceutical waste-water treatment. 

Computer simulations therefore have several inter-related objectives. In the long term one would hope that molecular level simulations of structure and bonding in liquid crystal systems would become sufficiently predictive so as to remove the need for costly and time-consuming synthesis of many compounds in order to optimise certain properties. In this way, predictive simulations would become a routine tool in the design of new materials. Predictive, in this sense, refers to calculations without reference to experimental results. Such calculations are said to be from first principles or ab initio. As a step toward this goal, simulations of properties at the molecular level can be used to parametrise interaction potentials for use in the study of phase behaviour and condensed phase properties such as elastic constants, viscosities, molecular diffusion and reorientational motion with maximum specificity to real systems. Another role of ab initio computer simulation lies in its interaction... 

These objective functions have to be minimised during the optimisation process to maximise the benefit in terms of ecological and economic sustainability. They are calculated on the basis of experimental results obtained for process parameter variations during the... 

Klima J, Frias-Ferrer A, Gonzalez-Garcy J, Ludvyk J, Saez V, Iniesta J (2007) Optimisation of 20 kHz sonoreactor geometry on the basis of numerical simulation of local ultrasonic intensity and qualitative comparison with experimental results. Ultrason Sonochem 14 19-28... 

Abstract A preconcentration method using Amberlite XAD-16 column for the enrichment of aluminum was proposed. The optimization process was carried out using fractional factorial design. The factors involved were pH, resin amount, reagent/metal mole ratio, elution volume and samphng flow rate. The absorbance was used as analytical response. Using the optimised experimental conditions, the proposed procedure allowed determination of aluminum with a detection limit (3o/s) of 6.1 ig L and a quantification limit (lOa/s) of 20.2 pg L, and a precision which was calculated as relative standard deviation (RSD) of 2.4% for aluminum concentration of 30 pg L . The preconcentration factor of 100 was obtained. These results demonstrated that this procedure could be applied for separation and preconcentration of aluminum in the presence of several matrix. 

Firstly, the optimisation shows how well the various thermodynamic quantities are matched and the excellent agreement with the experimentally observed phase diagram. It also shows a clear discrepancy between one set of experimental results and the optimised values for the mixing enthalpy in the liquid, emphasising the point that the combined thermodynamic and phase-diagram optimisation has been able to differentiate between conflicting experiments. 

An extensive literature survey shows that very little attention has been given to modelling and simulation of batch reactive distillation, let alone optimisation of such process. The published literature deals with the mathematical modelling and numerical integration of the resulting dynamic equations systems, with few presenting computer simulation vs experimental results. Only few authors have discussed the design, control and optimal operational aspects of batch reactive distillation processes. 

The influence of injection moulding conditions on the occurrence of surface defects on PVC pipe fittings was studied experimentally and by finite element analysis. Comparison of the experimental results with theoretical predictions allowed optimisation of the processing conditions for the production of parts having the required surface quality. 3 refs. 

The model-based dynamic optimisation results that were obtained from a fixed feed composition, same initial condition as the batch culture, and a feeding interval of 6-12 h, suggested an optimal cell cycle-arrest time at 126 h and supplementation with feed from 48 h onwards. The results of three different fed-batch cultures with identical supplementation strategies but various cell cycle-arrest times are shown in Fig.3. The viable cell concentration, Xy, was closely predicted up to about 80 h. However, after lOOh, Xv decreased significantly in all three cultures. The predicted MAb concentration was in accordance with the experimental results with only a slight under-prediction around 80-100 h. Both model predictions and experimental results indicated a small difference in MAb yield when the cultures were arrested at different times. The optimised fed-batch experiments involved a total of 9 shake flask cultures so the... 

The model was able to predict the culture dynamics for batch, fed-batch, and cell growth arrested cultures, especially up to the exponential growth phase, after which certain variable predictions deviated from the experimental results in fed-batch cultures, e.g. the viable cell concentration in the optimised fed-batch culture tended to be overestimated, and the simulated glucose uptake rate near the end of the fed-batch cultures was higher than observed. The model closely predicted the monoclonal antibody concentration in the optimised fed-batch culture despite an underestimation of the viable cell concentration. The model developed was able to direct experimental efforts to a more focused area in this case study. The monoclonal antibody yield in the optimised fed-batch culture was 3.5xl0 mg L" which was about 40% higher than the initial fed-batch culture. Further improvement of the model structure may be necessary to enhance its predictive capability. 

Concentration of HI over Hix solution by polymer electrolyte membrane electrodialysis was investigated using galvanodynamic and galvanostatic polarisation method. For this purpose, Hix solution with sub-azeotrope composition (HI L HjO = 1.0 0.5 5.8) was prepared. It was noticed that the electrical energy demand for electrodialysis of Hix solution decreases with increasing temperature. From the experimental results, it is concluded that the system resistance crucially affects the electrodialysis cell overpotential and hence the optimisation of cell assembly as well as the selection of low resistance materials should be carried out in order to obtain high performance electrodialysis cell. 

B, Wessling A Method of Preparing Compositions with Optimised Conductivity Behaviour. Summary of experimental results and various other articles. 

This approach is not always adequate if wide spectral ranges (several GHz) are required, due to fi-equency dependent reflections and resonances. The dimensions are so small and the measurements of complex impedance so difficult at MMW frequencies that careful experimentation is usually the only practical way to achieve optimisation. The result has been apertures in the range 2-5 mm wide X 0.2-0.5 mm high, or circular holes of 1-3 mm diameter in brass septa about 100 fim thick for frequencies in the 20-200 GHz region. The criteria for success have been whether the frequency range and sensitivity were adequate and the MMW structure background reasonably flat at the desired operating frequency (Section 6.1). 

Table 1 Selected GCxGC applications involving the analysis of persistent organohalogenated pollutants. For simplicity, only optimised experimental setups or those providing the most conclusive results have been mentioned...

An open volume, high isolation RF system suitable for pulsed NMR and EPR spectrometers with reduced dead time has been described. It comprises a set of three RF surface coils disposed with mutually parallel RF fields and a double-channel receiver (RX). Theoretical and experimental results obtained with a prototype operating at about 100 MHz have been reported. Each surface RF coil (diameter 5.5 cm) was tuned to 100.00 0.01 MHz when isolated. Because of the mutual coupling and the geometry of the RF coils, only two resonances at 97.94 MHz and 101.85 MHz were observed. These were associated with two different RF field spatial distributions. In continuous mode operation the isolation between the TX coil and one of the RX coils (singlechannel) was about —10 dB. By setting the double-channel RF assembly in subtraction mode the isolation values were optimised to about —75 dB. The described system was selected as a model for potential applications in solid-state NMR and in free radical EPR spectroscopy and imaging. 

Fifthly, a SOGA and MOGA tool were developed to optimise several parameterised operational strategies in various scenarios. The experimental results from the tools enabled the impact of coordinated management on SCP to be quantified. 

A comparison of the theoretical prediction of boundary B for low-velocity pneumatic conveying with the experimental results from the test rig described in this paper is shown in Fig, 7. The input data required for the model include the particle density (897 kg m ), the voidage of bulk solid (0.391), the coefficient of friction between the particles and wall (0.23), the coefficient of particle internal friction (0.5) and pipeline diameter (60 mm). The agreement between Ae modelling results and the experiments is quite good and the model can be used for design and optimisation purposes. Also, the model described in this paper is able to represent the mechanism of slug formation. 

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