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Aims: In this study, the relationship between morphology and cephalosporin C (CPC) production in a 30-l bioreactor culture of Cephalosporium acremonium M25 using a 3 : 7 seed mixture was investigated. In addition, the kinetic model was established and applied. Methods and Results: CPC production was performed in a 30-l bioreactor using a 3 : 7 seed mixture. It was recognized that a 3 : 7 seed mixture was able to reduce lag phase and enhance CPC production. The maximum CPC production and cell mass were 1AE96 and 81AE5 g l )1 respectively. Through a morphology study by observation using image analysis, it was concluded that changes of morphological features predicted the progressive production of CPC and that a morphology study could be useful in monitoring the CPC fermentation by C. acremonium M25. In the kinetics study, a kinetic model of CPC fermentation was developed and applied. The proposed model could adequately describe the fermentation of C. acremonium M25 in a 30-l bioreactor. Conclusions: CPC productivity was improved by using a 3 : 7 seed mixture in a 30-1 bioreactor. The changes in morphological features showed a very similar tendency with CPC production. A kinetic model of CPC fermentation was successfully established. Significance and Impact of the Study: The results of the present study suggest that the use of a 3 : 7 seed mixture inocula has considerable possibilities for improving CPC productivity if applied to industrial scale fermentations. Through morphology and kinetics study, the kinetic model to describe the morphological differentiation and CPC production by C. acremonium M25 was established.

The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions.

To reaffinn the use of a mainstream CMOS process for designing passive-like attenuator structures, a linear-controlled variable attenuator is realized with 0.35um CMOS process, which covers the broad frequency band (DC-I GHz). Compared to existing passive-like CMOS attenuators, it is demonstrated that this work advances the frequency band from MHz to GHz, and reduces the size. To elevate the limit of bandwidth, an alternative topology, which covers DC2GHz, is proposed as well. Operation principle and its characteristics are exolained in detail.