Ch. 6. Critical Systems Heuristics: The Idea and Practice of Boundary Critique

Critical systems heuristics (CSH) is a framework for reflective professional practice organised around the central tool of boundary critique. This chapter, written jointly by the original developer, Werner Ulrich, and Martin Reynolds, an experienced practitioner of CSH, offers a systematic introduction to the idea and use of boundary critique. Its core concepts are explained in detail and their use is illustrated by means of two case studies from the domain of environmental planning and management. A particular focus is on working constructively with tensions between opposing perspectives as they arise in many situations of professional intervention. These include tensions such as ‘situation’ versus ‘system’, ‘is’ versus ‘ought’ judgements, concerns of ‘those involved’ versus ‘those affected but not involved’, stakeholders’ ‘stakes’ versus ‘stakeholding issues’, and others. Accordingly, boundary critique is presented as a participatory process of unfolding and questioning boundary judgements rather than as an expert-driven process of boundary setting. The paper concludes with a discussion of some essential skills and considerations regarding the practice of boundary critique

Extraction of ß- carotene from palm oil mesocarp using sub-critical r134a

Sub-critical extraction of palm oil from palm mesocarp using R134a solvent was conducted via the dynamic mode to investigate the ability of R134a to extract ß-carotene. The yield of palm oil and the solubility of ß-carotene were investigated at 40, 60 and 80 °C and pressure range from 45–100 bar. The extracted oil was analysed for ß-carotene content using UV–Vis spectrophotometry. The results showed that palm oil yield increased with pressure and temperature. The maximum solubility of ß-carotene was obtained at 100 bar and 60 °C while the lowest solubility occurred at 80 bar and 40 °C. The higher concentration of extracted ß-carotene ranging from 330–780 ppm as compared to that achieved through conventional palm oil processing indicates that extraction of ß-carotene using R134a is viable

Extraction of ß-carotenes from palm oil mesocarp using sub-critical R134a

Sub-criticalextraction of palmoil from palmmesocarp using R134a solvent was conducted via the dynamic mode to investigate the ability of R134a to extract ß-carotene. The yield of palmoil and the solubility of ß-carotene were investigated at 40, 60 and 80 °C and pressure range from 45–100 bar. The extracted oil was analysed for ß-carotene content using UV–Vis spectrophotometry. The results showed that palmoil yield increased with pressure and temperature. The maximum solubility of ß-carotene was obtained at 100 bar and 60 °C while the lowest solubility occurred at 80 bar and 40 °C. The higher concentration of extracted ß-carotene ranging from 330–780 ppm as compared to that achieved through conventional palmoil processing indicates that extraction of ß-carotene using R134a is viable

Effects of supercritical carbon dioxide extraction parameters on virgin coconut oil yield and medium-chain triglyceride content

The extraction of coconut oil has been performed using supercritical carbon dioxide (SC-CO2). The extractions were performed at pressure and temperature ranges of 20.7-34.5 MPa and 40-80 °C, respectively. It was observed that almost all (more than 99%) of the total oil could be extracted. Response surface methodology (RSM) was applied to evaluate the effects of the parameters (pressure, temperature and CO2 consumption) on the extraction yield and medium-chain triglycerides (MCTs), in terms of the fatty acid content in the extracted oil. A correlation was established with p-values for both responses significant at the 95% confidence level