Nivel de purificación del agua utilizada en clínicas odontológicas universitarias / Level of water Purification that used the Odontological Clinics University

Las aguas que se utilizan en las clínicas odontológicas deberían estar libres de contaminantes y aceites, para asegurar la calidad en los trabajos realizados. Objetivo: Determinar el contaminante en el agua del sistema de las sillas odontológicas en la UNAH-VS. Materiales y métodos: Estudio transversal, cualitativo y cuantitativo, realizado del 18 de marzo al 4 de abril 2014. Exámenes realizados con la ayuda de un laboratorio privado mediante técnicas de recolección de aguas, utilizando previamente métodos de asepsias para eliminar todo microorganismo proveniente del exterior y no del agua específicamente del grifo, mangueras y ozonificador para mayor certeza del estudio. Las muestras fueron tomadas en el lavador de la clínica grande de la facultad de odontología, ozonificador colocado arriba del mismo y silla odontológica contigua al mismo lavador. Resultados: Los exámenes demostraron que el agua del grifo contiene 47% de recuento total bacteriano y 86.13% de dureza; en el ozonificador se encontró 15% de recuento total bacteriano y 81.17% de dureza total y el agua de la silla odontológica refleja 100% en recuento total bacteriano y 83.95% de dureza total del agua. Conclusiones: El grado de contaminación del agua de las clínicas odontológicas es mayor cuando sale por las mangueras de las sillas odontológicas, la cual va directamente a la boca del paciente. El ozonificador realiza un trabajo eficiente al reducir la dureza del agua así como también el recuento bacteriano...(AU)

Preparation of an adsorbent from pumice stone and its adsorption potential for removal of toxic recalcitrant contaminants

In recent years, proficient treatment of wastewaters containing recalcitrant and toxic compounds such as phenol has been a challenge. This study introduced and evaluated an efficient option for treating such wastewater. This experimental study was performed on phenol removal as a recalcitrant and toxic compound in aqueous solutions in 2011. The pumice stone was collected from a local mine. Collected samples were crushed and granulated using standard sieves [mesh size of 20]. CuSO[4] was used to modify prepared samples. The chemical composition and the surface area of the modified pumice were evaluated using X-ray fluorescence and N2 gas via Brunauer-Emmett-Teller isotherm and Belsorb software. Different parameters including of pH [3-12], contact time [20-120 min], phenol concentration [25-400 mg/L] and adsorbent dosage [0.25-1 g/L] were examined in a batch reactor. 93.5% of the phenol was removed under optimum experimental conditions of pH 3 and a 0.5 g/L adsorbent dose after 60 min contact time. The experimental adsorption isotherm the best fit with Freundlich equation model. The maximum amount of phenol adsorption onto modified pumice [MP] was 15.8 mg/g. Modified pumice is effective adsorbent for the removal of phenol from aqueous solution. Accordingly, it is feasible and promise adsorbent for treating polluted phenol streams

Colour removal from textile waste water using bioculture in continous mode.

One of the environmental problems being faced by textile industry is the removal of colour from the dye wastewater prior to discharge to local sewage treatment facilities or adjoining water courses. During the past two decades, several physico-chemical methods like adsorption, chemical treatment and ion pair extractions were adopted and have been proved to be costly and less effective. Biological treatment methods are comparatively cheap and considered to be the best alternative with proper analysis and environmental control. With this in mind, an attempt was made to evaluate efficiency with mixed microbial cultures for the decolourisation of the dye wastewater in continuous mode operation. Laboratory scale models of anaerobic reactor, activated sludge process and sand filter were fabricated and operated in series. The activated bioclean was inoculated in the anaerobic reactor. The characteristics and treatability of the textile dye wastewater were analysed. The sample taken for the study was combined effluent collected from the equalization tank in Common Effluent Treatment Plant (CETP), Tirupur. The experiments were conducted for different organic loading rates. Parameters such as colour, pH, COD, BOD, suspended solids, total dissolved solids, chlorides and sulphates for both the influent and effluent were evaluated. The removal efficiency of the anaerobic process, activated sludge process and sand filter for the above said parameters were studied.

Population ecology of a freshwater turtle Kachuga tentoria near Panchnada (Etawah: U.P.) and its role as water purifier.

The present study deals with biology, ecology and population dynamics of freshwater turtle Kachuga tentoria and its role as water purifier. The study area Panchnada is the site, where five important national rivers meet together and is preserving an appreciable population of nine species of fresh water turtles. Kachuga tentoria was located at all the sampling stations surveyed by the authors, and hence selected for the present study. Different activities (nesting, incubation, predation and other reproductive aspects), climatic conditions, habitat, population density and morphometric features were worked out in detail. A time bound conservation strategy is needed to save this species from extinction. In situ conservation will be more helpful for the recruitment of the population of this species. It will help in the "hatch and release programme" to clean different polluted national rivers.

Studies on the sorption of As(III) on the synthetic gel sodium potassium fluorophlogopite.

Sorption of As(III) has been studied on the synthesized gel close to Sodium potassium fluorophlogopite [Na0.5K0.5Mg3 (Si3 AlO10) F2] as a function of initial solution concentration at pH 2,4 and 7. The effect of parameters like equilibration time (0.5 - 24.0 hr), weight of the exchanger (30-150 mg) and temperature (25 degrees - 45 degrees c) has been investigated. The uptake of metal ion, As(III) has been expressed in terms of distribution coefficient i.e. (kd) values.

Removal of chromium by two aquatic pteridophytes.

In the recent years, the use of phytoremediation for ameliorating metal pollution has been gaining ground. This study explores the. possibility of utilising two common aquatic ferns, Salvinia molesta Mitchell and Azolla rubra R.Br. for scavenging chromium from solutions. Chromium removal from spiked solutions ranged from 40-99% during the seven day exposure. Results reveal their bioremoval capabilities and potentialfor use in wastewater decontaminant