Stages of developing the national system of accreditation of analytical laboratories, advantages and shortcomings of the system, as well as topical issues regarding accreditation in the context of the Federal Law No. 412-FZ (2013.12.28) are considered.

A review of the devices and systems on their base developed and produced by «VMK-Optoelektronika»: multichannel analyzers of emission spectra (MAES) based on multichip assemblies of linear solid-state detectors; Grand, Grand-Ékspert, Favorit, Ékspress, and Kolibri multichannel spectrometers; Vezuvii and Sharovaya Molniya electric-arc and spark-discharge generators; Globula and Kristall spectroanalytical instruments; Potok electric-arc facility for powder analysis using tspill-injection method, etc. are presented. Technical characteristics of the reviewed equipment are listed and discussed.

Formation of the collection of multielement reference standard materials (RSM) of natural and man-made composition in the Vinogradov Institute of SB RAS is focussed on ensuring the uniformity of measurements in geoanalysis. The use of MAES in arc atomic-emission analysis substantially simplified the analysis of reference material thus providing data for certification and assessing the heterogeneity and representative mass of the substance upon determination of the certain elements, stability of the substance during prolonged storage; checking of various standard samples against each other. Examples of the effective use of arc atomic-emission analysis in studying RSMs of different composition and genesis are given.

The results of using a multichannel analyzer of the emission spectra (MAES) with «Atom 3» program intended for multielement atomic-emission analysis of rocks are presented. The curves of evaporation in the ac arc discharge are studied for some chemical elements obtained from the rocks samples of different composition. The replacement of the visual decryption by the high-quality digital spectra processing enabled us to increase the analysis performance, extend the range of the designated contents and significantly improve the metrological characteristics of the determination of micro- and macro-components in rocks.

Application of the equipment produced at the «VMK-Optoelektronika» Ltd. for analysis of rocks, gold ores and non-ferrous metal ores at the Baikal branch of «Sosnovgeologiya» of the Federal State Unitary Geological Enterprise «Urangeologorazvedka» is considered. The advantages of using the aforementioned equipment in gold reconnaissance against classical approximate quantitative atomic emission analysis (gold atomic spectroscopy) with a visual interpretation of the spectrum are shown. The sets of analytical lines selected for gold determination provide a satisfactory quality of the results that match the requirements of industry guidelines. The metrological characteristics of the analysis procedure are evaluated in accordance with the current industry requirements for the development of methods of quantitative chemical analysis.

Study of natural nanoparticles of noble metals (NMs) is a rapidly developing area of modern geology and thus requires developing new precise instrumental methods of analysis. Further development of scintillation emission spectral analysis (SES) based on the use of a new spectrum recording system provides unprecedented opportunities for material research. We present the results of studying the samples obtained from hydrotherms near the volcanoes of the Kuril Islands using a modified SES method. It is shown that the proposed method of recording is not only a powerful tool for geochemists in determination of the quantitative content of NMs in a sample, but also provides information about the forms of the element present in the sample.

Population of the energy levels is calculated for 25 Fe I (atom) and 26 Fe II (ion) spectral lines in analytical zone of a two-jet arc argon plasmatron. It has been shown that Saha - Boltzmann equilibrium exists between the ion ground state and highly excited levels of the atom. The neutral ground and low excited energy levels (<4.0 eV) of the atom, however, are not in Saha - Boltzmann equilibrium with these levels. The results of the study are treated in terms of partial local thermodynamic equilibrium (pLTE) regarding ionizing mechanism of analyte spectrum excitation.

Capabilities of the analytical zones of high-power two-jet plasma are compared. A zone ahead of plasma jet confluence is shown to provide lower detection limits of the elements, however, strong dependence of the evaporation efficiency on the particle size is observed in analysis of heat-resistant materials. More effective evaporation of the samples occurs in a post-confluence, but the element detection limits are worse than in the region ahead of the jet confluence due to high background emission. The choice of the observation zone depends on a specific analytical goal.

Distributions of the temperature, intensity of the spectral lines of noble metals and the background signal in the height of the plasma plume are studied on a multi-channel emission spectrometer «Grand» with a two-jets plasma torch as the excitation source. It is shown that the angle between the electrodes of the plasma torch has a significant impact on the temperature distribution and intensity of the analytical lines of noble metals

An experience of using atomic emission optical time-resolved spectrometry in analysis of copper and ruthenium metal samples and geological powder samples is presented. Some analytical parameters of time-resolved spectrometry and characteristics are given.

We present the unique properties of nanoscale powder of metal iridium produced at the JSC «SPA «Ural Metals». The features of atomic emission spectral determination of the impurities present in the iridium nanopowder using evaporation from the graphite electrode channel in ac arc discharge are considered.

The results of using atomic emission spectral analysis in determination of the chemical composition of phosphate concentrates of fission products and impurities obtained upon pyrochemical reprocessing of the irradiated nuclear fuel are presented. A method of direct analysis of powders with their evaporation and electric arc starting is used to determine the chemical composition of low-solubility phosphates. To eliminate the impact of the physical and chemical properties and sample composition on the results of analysis we propose to open the sample in the electrode crater through phosphate recovery with carbon dust. To improve the reproducibility and minimize the impact of the sample chemical composition on the correctness of analysis we used a spectroscopic carrier BaCl₂. The optimal sample mass, «snifter»-type electrode parameters, current strength and exposure time are specified. The relative error of determinations ranges within 6.5 - 25.0%.

An approach to calculating the metrological characteristics of certified mixtures used to determine microimpurities in powder samples of steel, nickel-based alloys, ferro-alloys, and pure metals is developed. A comparison is made of the calculation mechanisms proposed by State Standard GOST 8.531 and the recommendation M-25 developed at the Institute of Standard Samples. The proposed approach provides a more rapid and accurate determination of the certified performance. The developed technique (comprising PGS-2 spectrometer equipped with a MAES analyzer) has been successfully used by the Department of Analytical Control since 2005 to certify more than 20 sets for the content of seven elements (As, Bi, Cd, Pb, Sb, Sn, Zn).

The results of practical application of a spectroanalytical stand «Kristall» produced by the VMK-Optoelektronika Ltd.company are presented. The main parameters that affect the rapidity of analytical procedures and easy handling of the spectroanalytical stand are considered. The performance features of novel «Kristall» stand are compared with those of a previous-generation UShT-4 stand. Distinguishing features of the «Kristall» stand are highlighted.

A metrological evaluation of the results of spectral analysis of UG4 state standard sample of carbon steel of the GSO (State Standard Sample) set 4165-91P; 2489-91P/2497-91P performed on a Polyvac E983 (Hilger Analitical) atomic emission vacuum spectrometer with photomultiplier tubes and Polyvac E980 and E983 atomic emission vacuum spectrometers upgraded with a MAES multichannel analyzer of emission spectra and a Sharovaya Molniya 250 generator is carried out using the procedure of testing ARL 3460 and ARL 4460 optical emission spectrometers. The Polyvac E980 spectrometer with a MAES analyzer and Sharovaya Molniya 250 generator showed the best results. The upgraded spectrometers are recommended to use in conditions of continuous production.

We present an experience of using vacuum optical spectrometer «Grand-Ékspert» in analysis of aerospace alloys based on magnesium, titanium and aluminum. Analytical parameters and range of determinable concentrations are listed and discussed.

Stability of the calibration characteristics used for determination of the main alloying additives in steel composition Al, C, Co, Cr, Cu, Mn, Mo, Nb, Ni, P, S, Si, Ti, V, W is studied using a «Grand-Ékspert» vacuum atomic emission spectrometer. The necessity of monthly recalibration is shown for copper and manganese whereas carbon, silicon, and vanadium did not require any recalibaration.

A possibility of determination of non-metallic inclusions in steels and alloys by optical emission spectrometry with spark excitation of the samples in argon using a «Grand-Ékspert» vacuum spectrometer equipped with a high-speed multichannel atomic emission spectrum analyzer based on a BLPP-2000 photodetector array is demonstrated. First quantitative results are reported.

Devices equipped with multichannel detectors provide simultaneous determination of alkali metals in the solutions of various compositions using flame photometry. A technique for simultaneous determination of Na, K, Li, and Rb in the samples of rocks, minerals, ores, silt and terrigenous sediments, soils and ash is developed. The presented technique matches the III category of accuracy according to Classification methods of laboratory analysis (OST 41-08-212-04). The effect of matrix and spectral effects are compensated due to the proper choice of optimum conditions for measurements of the analytical signals and calibration using the solutions of natural certified reference materials.

A high-transmission flame spectrometer with a triple-slot burner providing increased flame temperature is described. The spectrometer allows simultaneous determination of alkali and alkaline earth metals at a concentration of up to 1 μg/liter. The upper limit of the range of detectable concentrations at which the burner is not clogged exceeds 10 g/liter.

A multichannel atomic emission spectrum analyzer based on four BLPP-2000 photodiode arrays has been developed that provides recording a sequence of several thousand spectra with an exposure time of 0.4 during excitation of a powdered geological sample. Signal-to-noise ratio of Au 267.595 nm spectral line scintillation recorded by a BLPP-2000 array is shown to be 10 times higher than that recorded by a BLPP-369M1 array.

Achromatic lenses and a system for illuminating the entrance slit are developed for the spectrometers operating in the range of 190 - 470 nm. The dependence of the residual chromatic aberrations of the achromatic lenses on the wavelength is presented. It is shown that the illumination of the entrance slit is insensitive to the discharge displacement within ±3 mm.

A model microwave plasma source for atomic emission spectrometry of solutions is developed. A magnetron at a frequency of 2.45 GHz and a power of 750 W is used as a microwave energy generator. Argon with a flow rate of 3 liters/min is used as plasma-forming gas. The temperature of plasma with an aqueous aerosol is 4500 K. The achieved detection limits allow the instrument to be used for tap water analysis.

The main features of the «Atom» software as an important tool in automation of atomic-emission spectral analysis performed in the laboratories on the devices produced by the «VMK-Optoelectronika» company are presented.

A software for automatic profiling (wavelength calibration) of the spectrometers with MAES analyzers which implements a quality filtering of experimental values is developed. This quality parameter is estimated using an analytic function describing the shape of spectral lines with allowance for the effect of merged spectral lines and other criteria. Integral evaluation of the quality of calibration points provides an automatic significant reduction of the profiling error. The method is implemented in the framework of the «Atom» program.

An «Extended 2014» algorithm for mathematical processing of the sequences of time-resolved atomic emission spectra is developed to extract weak scintillations (flashes) of analytical lines from the noise and, as a consequence, to lower the element detection limits. Sequences of spectra are recorded using a multielement solid-state radiation detector with powder excitation in arc sources of spectra (for example, using the spill-injection method of powder introduction). The algorithm is compared with spectra processing algorithms previously implemented in «Atom 3.3» program. The algorithm described in this paper is advantageous for fewer adjustments, more correct determination of the background mask saving more points of the background that are used in the background shape determination. This improves the results of processing sequences of spectra, including statistic parameters such as the standard deviation of the calibration curve and the variances of convergence and adequacy. The signal-to-noise ratio of spectral line scintillations is also improved. The algorithm is implemented in the «Atom» program.

Results of studying an analytical potential of atomic (optical) emission digital spectrography with DC arc excitation of the spectrum of dried residue of liquid samples are presented. The results have been obtained on a MFS-8 spectral device modified with photodiode linear detector MAES. A possibility of increasing signal-to-noise ratio using higher arc current strength (20 A) and large amount of spectral buffer (0.15 mg NaCl) is shown. A universal technique of liquid biological samples analysis is developed using aqueous solutions of the salts of the elements as standard samples. The absence of the matrix impact is demonstrated in analysis of human saliva with dilution-addition method. The developed technique provides determination of a number of elements starting from n × 10^-7 g/liter in the sample n × 10 μl with the reproducibility less than 15 - 20 rel.%. Linear dynamic range of calibration curve is 3 - 4 orders of the concentration of the elements to be determined.

A modified procedure of preparing samples of medicinal herbs - hubs of trace elements - for spectral analysis is presented. The procedure consists in introduction of corrective additives into standard samples and can be taken as a basis of developing pharmacopoeial methods of arc atomic emission analysis of medicinal herbs.

An experimental setup for simultaneous multi-element atomic absorption spectral analysis comprising a continuous spectrum source, electrothermal atomizer (ETA), and a spectrometer with an operating range of 190 - 360 nm and a resolution of 0.025 nm is developed. The width of the entrance slit and the basic exposure time are optimized to reduce the limits of detection (LOD) of the elements to be determined. Calibration curves are constructed using a standard MES-11 sample with the following elements: Zn, Cd, Co, Cu, Ni, Bi, B, V, Ba, Pb, Mg, Sn, and Sb. The LOD for each element is determined using the calibration curve from the minimum value of the absorption signal that can be reliably determined. For a number of elements, the LOD values are comparable with those obtained on a ContrAA device with ETA; about an order of magnitude inferior to those of conventional atomic absorption spectrometry; and for most elements the LOD values match the Sanitary Requirements for the maximum permissible concentrations in drinking water in containers.

An algorithm for processing time sequences of atomic-absorption spectra recorded with a spectrometer with a MAES, electrothermal atomizer, and a continuous spectrum source is developed. The efficiency of the algorithm in comparison with the existing algorithm of the Atom program is tested in copper determination in aqueous solutions. The same recorded sequence of spectra has been processed using novel and existing algorithms. A more than twofold decrease in the detection limit is obtained using the developed algorithm.

Application of a device for electrothermal sample vaporization («VMK-Optoelectronika» Ltd., Russia) used to reduce the detection limits in determination of trace elements by ICP-AES is considered. Dependences of the analytical signal vs time for trace elements are studied. Operating conditions of electrothermal vaporization (ETV) are specified. The efficiency of using ETV in combination with ICP-AES is exemplified in analysis of high purity germanium dioxide with preliminary concentration of trace elements. Advantages and limitations of using ETV-ICP-AES procedure for trace analysis of high purity substances are discussed.