Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), usi...Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), using the process variable trajectories to monitoring the batch process is presented in this paper. It does not need to estimate or fill in the unknown part of the process variable trajectory deviation from the current time until the end. The approach is based on a MPCA method that processes the data in a sequential and adaptive manner. The adaptive rate is easily controlled through a forgetting factor that controls the weight of past data in a summation. This algorithm is used to evaluate the industrial streptomycin fermentation process data and is compared with the traditional MPCA. The results show that the method is more advantageous than MPCA, especially when monitoring multi-stage batch process where the latent vector structure can change at several points during the batch.展开更多
In the past several decades,SINOPEC has devoted continuously great efforts to the development of DCC technology,the only commercial process using heavy feeds aiming at propylene production.Recently,a series of researc...In the past several decades,SINOPEC has devoted continuously great efforts to the development of DCC technology,the only commercial process using heavy feeds aiming at propylene production.Recently,a series of research breakthroughs have been achieved in molecular refining.Based on the detailed analysis on the complex DCC reaction network,an innovative catalyst technology has been developed to Optimize Catalysis Kinetics (OCK in brief).The deep-cracking process can be improved with optimizing the availability of the active sites.The updated MFI and beta zeolites are used to boost the propylene selectivity.The latest generation catalyst DMMC-1 has been applied commercially.Compared with the best historical records in the past,the propylene yield upon application of the catalyst DMMC-1 increases by 2.4 m% coupled with an improved distribution of products.The DCC technology continues to assume a leading position for manufacturing propylene from heavy feedstocks.展开更多
The performance of Guatemala grass （Tripsacum laxum） under fertigation using hydroponic effluents at different dilution rates （effluent：water： 4：0, 3：1, 1：1, 1：3, 0：4） was compared to fertilisation using fa...The performance of Guatemala grass （Tripsacum laxum） under fertigation using hydroponic effluents at different dilution rates （effluent：water： 4：0, 3：1, 1：1, 1：3, 0：4） was compared to fertilisation using farmers＇ fertiliser rate of 475 kg 17：8：25/ha applied at planting ＋ 235 kg Sulphate of Ammonia/ha applied as top dressing one month after and 150 kg 17：8：25/ha applied after each harvest. Yield response obtained in plots fertilised using undiluted hydroponic effluents was 16.7% lower than that recorded in plots fertilised using farmers＇ fertiliser rate. The study showed that there-is potential for using hydroponic effluents （undiluted or diluted in the ratio of 3 HE： 1 water） in fodder production as it can provide sustainable yield in the range of 39.5-41.7 t/ha per harvest. Moreover, dilution rate of hydroponic effluents has a direct impact on crop development and fresh biomass yield. Fodder crop yield responded negatively to the increase dilution of hydroponic effluents from 4HE： 0 water to 3HE： 1 water, 1HE： 1 water and 1HE： 3 water. Consequently, the use of hydroponic effluents can eventually help to save on mineral fertiliser use and reduce cost of production while at the same time address environmental hazards related to hydroponic effluents disposal.展开更多
基金Supported by the National High-tech Program of China (No. 2001 AA413110).
文摘Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), using the process variable trajectories to monitoring the batch process is presented in this paper. It does not need to estimate or fill in the unknown part of the process variable trajectory deviation from the current time until the end. The approach is based on a MPCA method that processes the data in a sequential and adaptive manner. The adaptive rate is easily controlled through a forgetting factor that controls the weight of past data in a summation. This algorithm is used to evaluate the industrial streptomycin fermentation process data and is compared with the traditional MPCA. The results show that the method is more advantageous than MPCA, especially when monitoring multi-stage batch process where the latent vector structure can change at several points during the batch.
文摘In the past several decades,SINOPEC has devoted continuously great efforts to the development of DCC technology,the only commercial process using heavy feeds aiming at propylene production.Recently,a series of research breakthroughs have been achieved in molecular refining.Based on the detailed analysis on the complex DCC reaction network,an innovative catalyst technology has been developed to Optimize Catalysis Kinetics (OCK in brief).The deep-cracking process can be improved with optimizing the availability of the active sites.The updated MFI and beta zeolites are used to boost the propylene selectivity.The latest generation catalyst DMMC-1 has been applied commercially.Compared with the best historical records in the past,the propylene yield upon application of the catalyst DMMC-1 increases by 2.4 m% coupled with an improved distribution of products.The DCC technology continues to assume a leading position for manufacturing propylene from heavy feedstocks.
文摘The performance of Guatemala grass （Tripsacum laxum） under fertigation using hydroponic effluents at different dilution rates （effluent：water： 4：0, 3：1, 1：1, 1：3, 0：4） was compared to fertilisation using farmers＇ fertiliser rate of 475 kg 17：8：25/ha applied at planting ＋ 235 kg Sulphate of Ammonia/ha applied as top dressing one month after and 150 kg 17：8：25/ha applied after each harvest. Yield response obtained in plots fertilised using undiluted hydroponic effluents was 16.7% lower than that recorded in plots fertilised using farmers＇ fertiliser rate. The study showed that there-is potential for using hydroponic effluents （undiluted or diluted in the ratio of 3 HE： 1 water） in fodder production as it can provide sustainable yield in the range of 39.5-41.7 t/ha per harvest. Moreover, dilution rate of hydroponic effluents has a direct impact on crop development and fresh biomass yield. Fodder crop yield responded negatively to the increase dilution of hydroponic effluents from 4HE： 0 water to 3HE： 1 water, 1HE： 1 water and 1HE： 3 water. Consequently, the use of hydroponic effluents can eventually help to save on mineral fertiliser use and reduce cost of production while at the same time address environmental hazards related to hydroponic effluents disposal.
