For the detection of contaminations in urban water supply networks we introduce a continuous optimal control model governed by partial differential equations. We derive a linear mixedinteger model by discretization of the dynamics of the partial differential equations and by approximations to the cost functional. Finally, we present numerical results for artificial and real-world networks.

Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to level...

The bacterial diversity of a chronically oil-polluted retention basin sediment located in the Berre lagoon (Etang-de-Berre, France) was investigated. This study combines chemical and molecular approaches in order to define how the in situ petroleum hydrocarbon contamination level affects the bacterial community structure of a subsurface sediment. Hydrocarbon content analysis clearly revealed a ...

Microbial contamination is now more common than chemical contamination in Tibet, and water-borne microbes can cause a number of diseases that threaten public health. Thus, in order to clarify the spatiotemporal distribution of bacteria in small watersheds for which there is no data in Tibet, we set up four sampling points along an upstream-downstream transect of the Xincang River Basin. We coll...

INTRODUCTION People rely on the quality of the bottled drinking water, expecting it to be free of microbial contamination and health hazards. OBJECTIVES To evaluate the quality of bottled drinking water sold in Jaffna peninsula by analysing the physical, chemical and microbial contents and comparing with the recommended Sri Lankan Standard (SLS) values. METHODS All bottled water samples sol...

A screening in a sugar snap packaging company showed a converged build-up of aerobic psychrotrophic plate count (APC) (ca. 6.5 log CFU/100mL), yeasts and molds (Y&M), and lactic acid bacteria (LAB) (both ca. 4.5 log CFU/100mL) in the wash water in the absence of water sanitizer, and a low build-up of chemical oxygen demand (30 ± 5 mg O2/L) and turbidity (5.2 ± 1.1 NTU). Decontamination experime...

An ecologic study was performed to examine the relation between the incidence of leukemias and the occurrence of volatile organic chemical (VOC) contamination of drinking water supplies within a study area comprised of subpopulations differentially exposed to drinking water VOCs (trichloroethylene and related solvents). Populations served by community water supplies were classified into exposur...

Commonly, the product spectroscopic sequences available on commercial scanners don’t take full advantage of the scanner hardware. At an intermediate, now widely available field of 3T, issues like chemical shift displacement and contamination by external lipids become a problem, especially because of the low γB1 and the slow prescribed gradients. In this context, detection of metabolites at low ...

Water resources are crucial in developing any area as they serve a major source of potable, agricultural, and industrial water. contamination, caused by natural anthropogenic activities, poses significant threat to public health globally. This review synthesizes data from various studies published national international journals, well reports governmental non-governmental organizations. Our pri...