the physico-chemical parameters, nutrient status and heavy metal ions of huluka and alaltu rivers of ambo, ethiopia were studied. temperature, ph, electrical conductivity, co2 content, total dissolved solids, hardness, dissolved oxygen, ca2+, mg2+, cl-, nitrate, phosphate and sulphate have been determined along with selected heavy metals to assess the various water quality profiles along the ri...

background: health-care-associated infections are a major threat to the safety of patient care. control of such problem is a major criterion for hospital accreditation. this study was aimed to determine the developing use of chemical (class 6 products) and biological indicators in tabriz district hospitals since 1997 to 2011. methods: we conducted this time-trend interventional study with all o...

background: according to the health world organization drinking water must be free of chemicals and microbial contaminations which are risk to human health. therefore water quality control is very important. the purpose of this study is investigating the chemical quality and chlorination status of drinking water in kashan’s villages. methods: this cross-sectional study was conducted on drinking...

Ground water is sampled to assess its quality for a variety of purposes. Whatever the purpose, it can only be achieved if results are representative of actual site conditions and are interpreted in the context of those conditions. Substantial costs are incurred to obtain and analyze samples. Field costs for drilling, installing, and sampling monitoring wells and laboratory costs for analyzing s...

The solution of chemical kinetics is one of the most computationally intensive tasks in atmospheric chemical transport simulations. Due to the stiff nature of the system, implicit time stepping algorithms which repeatedly solve linear systems of equations are necessary. This paper reviews the issues and challenges associated with the construction of efficient chemical solvers, discusses several...