Feasibility Study of a Simple and Low-Cost Device for Monitoring Trihalomethanes Presence in Water Supply Systems Based on Statistical Models

This paper describes a new method for predicting trihalomethanes (THMs) presence in networks of water supply systems, using a low-cost device that permits a fast monitoring of concentrations without need of complex analysis made in laboratories. This method, based on statistical models, allows the estimation of THM concentration by monitoring parameters whose determination is direct and easy, and therefore, THM presence can be carried out in real-time. These parameters values are introduced in a multiple regression model resulting in the concentration of THMs levels. This model has taken into account parameters compulsory in water quality analysis and it has been shown that six parameters are enough to determine accurately THM concentration. In addition, the feasibility of a low-cost device that directly gives THM concentration is demonstrated. This device can be easily designed to be transported to different points of the water supply network where it is intended to make control campaigns.We gratefully acknowledge financial support for this work from AGBAR Group (Aguas de Barcelona, Water Works Holding

A predictive model for chloroform formation from humic substances

This item was digitized from a paper original and/or a microfilm copy. If you need higher-resolution images for any content in this item, please contact us at [email protected]

MICROWAVE SPECTRUM AND PSEUDOROTATION IN TETRAHYDROFURAN.

This work was supported by the National Science Foundation.Author Institution: Department of Chemistry, University of CaliforniaThe microwave spectrum of tetrahydrofuran has been assigned in the ground vibrational state and in eight excited states of the pseudorotation mode. The rotational constants exhibit an unusual dependence upon the pseudorotational quantum number. The separation of the first pairs of levels has been determined from the effects of a coupling term linear in the overall rotational momentum and in the pseudorotational momentum. These data are interpreted in terms of a quantum mechanical Hamiltonian which contains the inertial constant as a function of the pseudorotational angle and a small barrier to pseudoratation. This barrier is about 20 cm$^{-1}$ for the two-fold term and 2 cm$^{-1}$ for the ten-fold term