The first direct enantioselective catalytic alpha-chlorination of aldehydes has been accomplished. The use of enamine catalysis has provided a new organocatalytic strategy for the enantioselective chlorination of aldehydes to generate alpha-chloro aldehydes, an important chiral synthon for chemical and medicinal agent synthesis. The use of imidazolidinone 3 as the asymmetric catalyst has been f...

The article evaluated the degradation of the captopril in aqueous solution after ozonation and chlorination. The process was continuously monitored focusing on the identification, mass spectrometry and elucidation of its by-products by applying direct infusion and high performance liquid chromatography, electrospray ionization high resolution mass spectrometry, in the negative ion mode. The cyt...

Chlorine-terminated Si(111) surfaces prepared through the wet-chemical treatment of H-terminated Si(111) surfaces with PCl5 (in chlorobenzene) were investigated using ultrahigh vacuum scanning tunneling microscopy (UHV cryo-STM) and tunneling spectroscopy. STM images, collected at 77 K, revealed an unreconstructed 1 x 1 structure for the chlorination layer, consistent with what has been observe...

We evaluated the ability of UNICEF-designed pot-chlorinators to achieve recommended free residual chlorine (FRC) levels in well water in Bissau, Guinea-Bissau, during a cholera outbreak. Thirty wells were randomly selected from six neighbourhoods. Pot-chlorinators--perforated plastic bottles filled with gravel, sand and calcium hypochlorite granules--were placed in each well. FRC was measured b...

Haloacetamides (HAcAms), an emerging class of nitrogenous disinfection by-products (N-DBPs) of health concern, have been frequently identified in drinking waters. It has long been appreciated that free amino acids (AAs), accounting for a small fraction of the dissolved organic nitrogen (DON) pool, can form dichloroacetamide (DCAcAm) during chlorination. However, the information regarding the im...

After human consumption, pharmaceutically active substances can be excreted and enter the effluent treatment facilities. Often degradation in sewage and water treatment and the environment is incomplete, resulting in the formation of transformation products. Within the Pharmas project (EU grant agreement no. 265346) three anticancer drugs were evaluated for the formation of stable transformatio...

The objectives of the studies were to determine if radiation and chlorine acted in a simple additive process or if a nonadditive increase in inactivation occurred when chlorination followed γ-irradiation both in vitro and in situ. Separate studies evaluated the effects of γ-irradiation (0.2 kGy at 20 ◦C), chlorination (0.5 ppm for 10 min), or irradiation followed by chlorination of Salmonella, ...

Chlorine is most readily available in the form of chloride of lime (bleaching powder), which can readily be obtained commercially. This, if freshly made, should contain 33 per cent, of free or active chlorine. It loses its efficacy on keeping, especially during hot weather; but this loss may be retarded by the addition of 25 per cent, of quicklime. Samples of the bleaching powder used should be...

Haloacetamides (HAcAms) are an emerging class of nitrogenous disinfection by-products (N-DBPs) of health concern. However, there are very limited data on the formation and speciation of the nine bromine- and chlorine-containing haloacetamides (HAcAm9). In the study, their formation and speciation during chlor(am)ination were investigated for a group of waters with a range of specific ultraviole...