The complete works of Mark Twain

- Autobiography. - [v.1.] The adventures of Tom Sawyer. -[v.2.] The innocents abroad. - [v.3.] Pudd'nhead Wilson. - [v.4.] The American claimant. - [v.5.] Connecticut Yankee in King Arthur's court. -[v.6.] Roughing it. - [v.7.] Life on the Mississippi. - [v.8.] The mysterious stranger. -[v.9.] The adventures of Huckleberry Finn. - [v.10.] The gilded age. - [v.11.] A tramp abroad. -[v.12.] What is man? - [v.13.] Following the equator. -[v.14.] Tom Sawyer abroad. - [v.15.] The man that corrupted Hadleybrug. -[v.16.] In defense of Harriet Shelley. - [v.17.] Joan of Arc. - [v.18.] The 30,000 bequest. - [v.19.] Sketches, new and old. - [v.20.] Europe and elsewhere. - [v.21.] - The Prince and the pauper. - [v.22.] Mark Twain's notebook. - [v.23.] Christian Science. -[v.24.] Mark Twain's speeches.

Ecological studies on high-rate biological filters with special reference to microbial biosynthesis and nitrification

Pilot scale studies of high rate filtration were initiated to assess its potential as either a primary 'roughing' filter to alleviate the seasonal overloading of low rate filters on Hereford sewage treatment works - caused by wastes from cider production - or as a two stage high rate process to provide complete sewage treatment. Four mineral and four plastic primary filter media and two plastic secondary filter media were studied. The hydraulic loading applied to the primary plastic media (11.2 m3 /m3 .d) was twice that applied to the mineral media. The plastic media removed an average around 66 percent and the mineral media around 73 percent of the BOD applied when the 90 percentile BOD concentration was 563 mg/1. At a hydraulic loading of 4 m3 /m3 .d the secondary filters removed most of the POD from partially settled primary filter effluents, with one secondary effluent satisfying a 25 mg/1 BOD and 30 mg/1 SS standard. No significant degree of nitrification was achieved. Fungi dominated the biological film of the primary filters, with invertebrate grazers having little influence on film levels. Ponding did not arise, and modular media supported lower film levels than random-fill types. Secondary filter film levels were low, being dominated by bacteria. The biological loading applied to the filters was related to sludge dewaterability, with the most readily conditionable sludges produced by filters supporting heavy film. Sludges produced by random-fill media could be dewatered as readily as those produced by low rate filters treating the same sewage. Laboratory scale studies showed a relationship between log effluent BOD and nitrification achieved by biological filters. This relationship and the relationship between BOD load applied and removed observed in all filter media could he used to optimise operating conditions required in biological filters to achieve given effluent BOD and ammoniacal nitrogen standards.

Study of the behavior of iron ore particles in spiral concentrators

Les spirales sont des appareils de séparation gravimétrique principalement utilisés dans l’industrie du traitement du minerai de fer. La classification des particules dans la pulpe s’effectue lors de la descente dans les spires en fonction de leur taille et leur densité, des conditions d’opération et de la géométrie de la spirale. L’effet des conditions d’opération (pourcentage solide, débit d’alimentation et débit d’eau de lavage) est évalué sur la performance des spirales en utilisant une spirale WW6E installée à COREM pour traiter un minerai de fer de ArcelorMittal, Québec. Les résultats montrent l’effet dominant du débit de l’eau de lavage et son impact majeur sur les particules grossières. Un circuit fermé de trois spirales parallèles avec 3, 5 et 7 tours est utilisé afin d’évaluer l’influence du nombre de tours. Les résultats préliminaires indiquent que la spirale trois tours fonctionne bien pour le nettoyage tandis que la 7 tour est robuste pour l’ébauchage et l’épuisage.