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Biomedical subjects

G Zhu

Publications and source records attributed to G Zhu.

291 records · Page 17Linked to original sources
PubMedDate not supplied

Pilot scale study on retrofitting conventional activated sludge plant for biological nutrient removal.

Eutrophication of receiving waters due to the discharge of nitrogen and phosphorus through the wastewater effluent has received much interest in recent years. Numerous techniques have been proposed and aimed at retrofitting the existing conventional activated sludge process for nutrient removal. A pilot-scale research program was conducted to evaluate the effectiveness of a biological nutrient process for this purpose. The results indicated that creating an anoxic/anaerobic zone before aeration basin significantly enhances total phosphorus (TP) and total nitrogen (TN) removal. Without internal cycle, about 80 percent TP and TN removal were respectively achieved under their optimal conditions. However, adverse trends for phosphorus and nitrogen removal were observed when the ratio of return sludge to the influent was varied in the range between 0.5 and 3.0. The total phosphorus removal decreased as the concentration of BOD5 in the mixture of influent and return sludge decreased. Improved sludge settling properties and reduced foaming problems were also observed during the pilot plant operation. Based upon experimental results, the strategies to modify an existing conventional activated sludge plant into a biological nutrient removal (BNR) system are discussed.

Acinetobacter↗
PubMedDate not supplied

Recognition of the bouquet of Chinese spirits by artificial neural network analysis.

Forty-six samples of Chinese spirits, whose bouquets were determined by sensory evaluations, and 17 compounds characteristic of the flavors determined by gas chromatography/gas chromatography-mass spectrometry (GC/GC-MS), were subjected to neural network analysis and their corresponding factor scores developed. To make the bouquet recognition more efficient, an improved artificial back-propagation neural network (BPNN) was applied. In each kind of data, the BPNN was trained repeatedly until the error rate was less than the predetermined threshold error; then the trained network was applied to the test set that was not involved in the training process to establish the validity of the network, and a correct prediction rate of 100% was obtained. The BPNN provided a correlation between the data offered from sensory evaluations and the data of chemical compositions determined by instrumental analysis. The BPNN approach is feasible regardless of whether the crude data or the factor scores are used; however, recognition results were better with the latter than with the former. In a comparison of all the results obtained by BPNN, cluster analysis, and discriminant analysis, the method of artificial neural network analysis appeared to be the optimal technique for recognizing the bouquet of Chinese spirits.

Alcoholic Beverages↗