Generation atoms

This experiment describes a fixed-size simplex optimization of a system involving four factors. The goal of the optimization is to maximize the absorbance of As by hydride generation atomic absorption spectroscopy using the concentration of HCl, the N2 flow rate, the mass of NaBH4, and reaction time as factors. 

FLOW INJECTION ELECTROCHEMICAL HYDRIDE GENERATION ATOMIC ABSORPTION SPECTROMETRY EOR THE DETERMINATION OE ARSENIC... 

DETERMINATION OF ARSENIC (As) IN NATURAL AND WASTE WATER USING HIDRIDE GENERATION ATOMIC FLUORESCENCE SPECTROMETRY... 

Arsenic is both toxic and cai cinogenic element. It is necessary to have a fast, reliable and accurate method for determination of ai senic in water. The hydride-generation atomic fluorescence spectrometry (HG AFS) is one of the simple and sensitive techniques for the determination of this element in various types of waters. 

Photolytic methods are used to generate atoms, radicals, or other highly reactive molecules and ions for the purpose of studying their chemical reactivity. Along with pulse radiolysis, described in the next section, laser flash photolysis is capable of generating electronically excited molecules in an instant, although there are of course a few chemical reactions that do so at ordinary rates. To illustrate but a fraction of the capabilities, consider the following photochemical processes ... 

Vol. 130. Hydride Generation Atomic Absorption Spectrometry. By Jiri Dedina and Dimiter L. Tsalev... 

Zhang X, Cornelis R, De Kimpe J, and Mees L (1996) Arsenic speciation in serum of uraemic patients based on liquid chromatography with hydride generation atomic absorption spectrometry and on-line UV photo-oxidation digestion. Anal Chim Acta 319 177-185. 

Munoz O, Velez D, Montoro R (1999) Optimization of the solubilization, extraction and determination of inorganic arsenic [As(III) i- As(V)] in seafood products by acid digestion, solvent extraction and hydride generation atomic absorption spectrometry. Analyst 124 601-607. 

Glow discharge is essentially a simple and efficient way to generate atoms. Long known for its ability to convert solid samples into gas-phase atoms, GD techniques provide ground-state atoms for atomic absorption or atomic fluorescence, excited-state atoms for atomic emission, and ionised atoms for MS [158], Commercial instrumentation has been developed for all these methods, except for GD-AFS and pulsed mode GD. 

Samanta G, Chakraborti D. 1996. Flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) and spectrophotometric methods for determination of lead in environmental samples. Environmental Technology 17(12) 1327-1337. 

Hydride Generation Atomic Absorption Spectrometry High Performance Liquid Chromatography High Performance Thin-Layer Chromatography High Resolution... 

Sturgeon et al. [59] have described a hydride generation atomic absorption spectrometry method for the determination of antimony in seawater. The method uses formation of stibene using sodium borohydride. Stibine gas was trapped on the surface of a pyrolytic graphite coated tube at 250 °C and antimony determined by atomic absorption spectrometry. An absolute detection limit of 0.2 ng was obtained and a concentration detection limit of 0.04 pg/1 obtained for 5 ml sample volumes. 

Negative interferences by transition metal cations such as nickel and copper and nitrite were observed. However, these interferences have also been reported for the hydride generation atomic absorption method, and are due to... 

Hydride Generation Atomic Spectrometry Arsenic and Antimony... 

It has been reported that the differential determination of arsenic [36-41] and also antimony [42,43] is possible by hydride generation-atomic absorption spectrophotometry. The HGA-AS is a simple and sensitive method for the determination of elements which form gaseous hydrides [35,44-47] and mg/1 levels of these elements can be determined with high precision by this method. This technique has also been applied to analyses of various samples, utilising automated methods [48-50] and combining various kinds of detection methods, such as gas chromatography [51], atomic fluorescence spectrometry [52,53], and inductively coupled plasma emission spectrometry [47]. 

Total dissolved Fe and Mn were analyzed directly by flame atomic absorption spectrometry (AAS). As was measured by AAS with hydride generation (HG-FIAS). Total dissolved Se concentrations were determined by hydride-generation atomic fluorescence spectrometry (Chen etal., 2005). 

The atomic absorption spectrophotometric methods discussed in section 12.10.2.2 [122, 124] has been applied to the determination of selenium in sediments. Itoh et al. [165] and Cutter [122] (section 12.10.2.2) have used hydrogen generation-atomic absorption spectrophotometric techniques to determine selenium in non-saline sediments. Cutter [122] was able to distinguish between selenite, selenate, total selenium and organic selenium in sediments. 

Lee [2] using a hydride generation atomic absorption spectrometric method has investigated the bioaccumulation of bismuth on marine sediment samples collected in Narragensett Bay and the North Pacific Ocean. 

Compare atomic absorption (both flame and graphite furnace), ICP, flame photometry, cold vapor mercury, hydride generation, atomic fluorescence, and spark emission in terms of ... 

---