PubMed · 11612735
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
K H Leven. 1991. [Not Available].. https://pubmed.ncbi.nlm.nih.gov/11612735/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
The occurrence and the fate of heavy metals (Cd, Pb, Mn, Cu, Zn, Fe and Ni) during the wastewater treatment process were investigated in the wastewater treatment plant (WTP) of the city of Thessaloniki, northern Greece, operating in the activated sludge mode. For this purpose, wastewater and sludge samples were collected from six different points of the plant, namely, the influent (raw wastewater, RW), the effluent of the primary sedimentation tank (primary sedimentation effluent, PSE), the effluent of the secondary sedimentation tank (secondary sedimentation effluent, SSE), sludge from the primary sedimentation tank (primary sludge, PS), activated sludge from the recirculation stream (activated sludge, AS), and the digested/dewatered sludge (final sludge, FS).The distribution of metals between the aqueous and the solid phase of wastewater was investigated. Good exponential correlation was found between the metal partition coefficient, logK(p), and the suspended solids concentration. The mass balance of heavy metals in the primary, secondary and the whole treatment process showed good closures for all metal species. The relative distribution of individual heavy metals in the treated effluent and the sludge streams indicated that Mn and Cu are primarily (>70%) accumulated in the sludge, while 47-63% of Cd, Cr, Pb, Fe, Ni and Zn remain in the treated effluent.
OBJECTIVE: To report on the career of Professor Nicolas Taptas of Constantinople (1871-1955) and his contribution to the development of an artificial larynx. STUDY DESIGN: Historical review. METHODS: The unpublished documents of Taptas's family archives and one of his papers, describing his own original technique for voice rehabilitation after total laryngectomies, were studied. RESULTS: In his texts, Taptas described the application of external laryngeal prostheses in one of his patients who underwent total laryngectomy. Taptas meticulously recorded his own first successful attempt in a woman with cancer of the larynx. He was one of the first scientists who, at the end of the 19th century, devised an external laryngeal prosthesis, which had the advantage of rehabilitating a sufficiently strong whispering voice; by using a prototype valve, he avoided problems of aspiration of liquids and food to the bronchi. CONCLUSION: Nicolas Taptas's contribution to the development of the artificial larynx was vital because he devised and applied one of the first external laryngeal artificial prostheses with satisfactory functional results.