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This paper emphasizes a groundwater quality assessment using thirty-seven hydro-geological drillings, located in vulnerable and non-vulnerable areas in Botosani County as regarding nitrate and nitrites based pollutants and also phosphates and ammonium, during 2001-2008. The groundwater quality from vulnerable areas is within allowed limits. It was observed a decrease of nitrates and nitrites concentration in four locations designated as vulnerable zones regarding nitrates. In non-vulnerable areas, the groundwater quality deteriorated between 2006-2008, in terms of ammonium, nitrites and nitrates content. In some hydrogeological drillings, like Sadoveni and Stefanesti, the nitrites concentration (1.54 mg/L, 1.37 mg/L respectively) exceeded the legal accepted limit. The ammonium concentration in non-vulnerable areas also exceeded the limit of 0.5 mg/L. By token of the results of this monitoring activity the risk of groundwater pollution with nitrates was reassessed. MMDD Order 1552/743/2008 approved a new list of localities where sources of nitrates exist from agricultural activities; in Botosani County seventy-seven new localities were designated as vulnerable areas regarding nitrates pollutants.

The electrochemical deposition of zinc and combinations with elements of the 8th group of the Periodic System (nickel, cobalt, iron) have good properties for anticorrosive protection, compared with pure zinc. For steel pieces, these films delay apparition and formation of white and red iron oxide. We used solutions with different concentrations of zinc chloride, nickel chloride and potassium chloride. To analyze the results we used the optic microscope and the X-ray diffraction.

The mechanism of electrochemical deposition of nickel and zinc-nickel alloy was described as in actually science literature. To prove practically the proposed mechanism, it was used as interesting effect which consists in an increase of the deposited mass more than Faraday law predicts. Nickel was deposited and zinc-nickel alloy was codeposited using a potentiostat-galvanostat Parstat 2273 coupled with an Electrochemical Quartz Crystal Microbalance (EQCM). The mass distribution of deposited metal and alloy was monitored during the process, together with electrochemical parameters (potential, current density, and temperature). The electrodeposited layers were characterized with SEM-EDX techniques. A mathematical relation referring to the process was proposed in order to describe the evolution of mass electrode versus time in the first step of the electrodeposition.

ZnO:Co thin films are prepared by electrochemical deposition at different overpotentials and investigated by scanning electron microscopy, optical spectroscopy, and cathodoluminescence, X-ray photoelectron spectroscopy and Kerr magnetometry (MOKE). An increase of structural disorder and crystallite reorientation are observed for cobalt-doped samples. MOKE magnetometry revealed room-temperature ferromagnetic behavior only for ZnO:Co deposited at À850 mV. These are the samples with the lower cobalt content and lowest structural perturbation of the ZnO matrix by cobalt.