AA-7800

In the case of adding the graphite (electrothermal) atomizer GFA-7800 to the AA-7800F/AAC system, automatic change of atomizers and adjustment of their positions is provided, which allows for effective high-performance analysis of a large number of elements. The ability to use two types of flames: standard С₂Н₂ – air and high-temperature С₂Н₂ – N₂О allows you to analyze almost all elements for which the atomic absorption method can be applied. The flame atomizer of the Shimadzu device consists of a titanium burner (two options, depending on the type of the required flame), a spray chamber made of heat-resistant and impact-resistant fluorinated plastic, a platinum-iridium atomizer and a ceramic impactor. Due to its unique design and materials, it is practically not subject to corrosion. The optimal height of the burner is set automatically (if the automatic atomizer adjustment unit is installed) or manually. Highly sensitive graphite furnace is used to determine trace amounts of elements. Effective for the analysis of refractory elements (e.g.: Cr, B, Ba, etc.) and elements whose analytical lines are located in the ultraviolet part of the spectrum (e.g.: hydride-forming As, Se, Sb). The furnace design, precise temperature control, and computer control of gas flows ensure an increased service life of the graphite cuvette – over 2000 cycles of chromium atomization in acidic solutions (0,1% HNО₃) at 2800 ^ОС.

One ASC/ASK-7800 autosampler can be used for both flame and furnace measurement. There is no need to prepare two autosamplers. The simple design allows the autosampler to be moved to the left or right. Connecting the autosampler directly to the main unit minimizes the space for equipment installation and simplifies maintenance. The ASC-7800 design ensures that the sampling nozzle is washed in an overflow-type washing tank every time after the measurement of each sample is completed, which minimizes the possibility of contamination of the next sample to a level below 10^-4 even when measuring a series of samples. Before introducing the sample, a mixing procedure can be performed for up to four different samples. (Of course, samples can be introduced without mixing.) As the injection nozzle (sampling tube), either a fluorinated polymer tube or pipette-type tips can be selected. In the case of electrothermal analysis, samples can be automatically diluted with water.

The standard is equipped with two types of background correction – the deuterium lamp correction method (D2) and the high-speed self-reversing line correction method (SR, the modern Smith-Hefty method). The D2 method is a highly sensitive background correction. The features of this method allow the analysis of samples with a simple matrix, allowing the analysis of purified, tap and ecological water for measuring trace levels of impurities or environmental analysis. The SR method, on the contrary, allows the analysis of samples with a complex matrix, allowing the correction of the background in the entire wavelength range (from 185 nm to 900 nm). It especially analyzes objects where different elements are present, which have closely spaced spectral lines (for example, pairs: Al(309.28 nm) – Mg(309.30 nm); As(193.76 nm) – Fe(193.73 nm); Pb(217.00 nm) – Fe(216.95 nm); Zn(213.856 nm) – Fe(213.8589 nm)).

The AA-7800 atomic absorption spectrophotometer, depending on the tasks, can be supplied in various configurations, including: basic flame version with manual adjustment of the burner position; flame version with automatic adjustment of the burner position; flame version with nozzles resistant to organic solvents; flame version with HVG attachment; version with an electrothermal atomization unit and an autosampler; combined version with flame and electrothermal atomizers and an autosampler. The structural features of the device allow it to be easily retrofitted with the necessary units directly in the user’s laboratory by Shimadzu specialists.

Програмне забезпечення WizAArd 5 дає змогу проводити автоматичний аналіз згідно зі складеним алгоритмом, що повністю виключає можливі помилки оператора. WizAArd 5 забезпечує дотримання протоколів QC/QA і валідацію відповідно до GLP/GMP.