A sensitive method was proposed and optimized for the determination of total mercury in fish tissue by using wet digestion, followed by cold vapor atomic absorption spectrometry (CVAAS) at the main resonance line of mercury (184.9 nm). The measurements were made using a new type of a non-dispersive mercury minianalyzer. This instrument was initially designed and built for atmospheric mercury-va...

background: dental clinics are known to be one of the largest users of toxic inorganic mercury. it is well documented that dentists and dental assistants who work with amalgam are chronically exposed to mercury vapor. this study investigates exposure to mercury vapor in a dental clinic. methods: gbc cold vapor atomic absorption spectrometry (aas), using sodium borohydride as the reducing agent,...

A new and simple method followed by atomic absorption spectrometry has been developedfor indirect determination of ascorbic acid (AA). The proposed method was based on the oxidationof AA to dehydroascorbic acid with Cu2+cation(200mgL-1)in an ammonium thiocyanatesolution atpH2.4. AA reduces Cu2+to Cu+followed by the precipitation of Cu+ with SCN-. Then, the excess ofCu2+in the solution was measu...

In this article, we report the first successful preparation of single- and few-layers of tantalum diselenide (2H-TaSe₂) by mechanical exfoliation technique. Number of layers is confirmed by white light contrast spectroscopy and atomic force microscopy (AFM). Vibrational properties of the atomically thin layers of 2H-TaSe₂ are characterized by micro-Raman spectroscopy. Room temperature Raman mea...

Extensive distribution of hazardous substances in food chain and the deleterious effect of their residues on public health are a great concern of the society. Chicken eggs, as one of the most popular food commodities, in different parts of Tehran (Iran) were analyzed for two groups of hazardous substances including some organochlorine pesticides (OC) such as aldrin, lindane, dieldrin, dichlorod...

The activity of polonium (210)Po and uranium (234)U, (238)U radionuclides, as well as trace metals in mosses, collected from Sobieszewo Island area (northern Poland), were determined using the alpha spectrometry, AAS (atomic absorption spectrometry) and OES-ICP (atomic emission spectrometry with inductively coupled plasma). The concentrations of mercury (directly from the solid sample) were det...

Atomic absorption spectroscopy Atomic absorption spectroscopy (AAS) was developed in the early 1950’s by Alan Walsh. It works on the principle that certain elements absorb certain wavelengths, and this level of absorption is characteristic of each element. Also, electrons in atoms can only exist in particular energy levels, and when an electron moves to a higher energy level, electromagnetic ra...