GOST 11739.3-99

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  ГОСТ 11739.3-99

GOST 11739.3−99 Alloys aluminum casting and wrought. Methods for determination of beryllium

GOST 11739.3−99

Group B59

INTERSTATE STANDARD

ALLOYS ALUMINIUM CAST AND WROUGHT

Methods for determination of beryllium

Aluminium casting and wrought alloys. Methods for determination of beryllium

ISS 77.120.10
AXTU 1709

Date of introduction 2000−09−01

Preface

1 DEVELOPED by JSC «Russian Institute of light alloys» (JSC VILS), the Interstate technical Committee for standardization MTK 297 «Materials and semi-finished products of light alloys"

INTRODUCED by Gosstandart of Russia

2 ADOPTED by the Interstate Council for standardization, Metrology and certification (Protocol No. 16−99 dated 8 October 1999)

The adoption voted:

3 Resolution of the State Committee of the Russian Federation for standardization and Metrology dated February 18, 2000 N 41-St inter-state standard GOST 11739.3−99 introduced directly as state standard of the Russian Federation from September 1, 2000

4 REPLACE GOST 11739.3−82

1 Scope

This standard specifies the photometric (with a mass fraction of beryllium from 0.001% to 1.0%), fluorescent (with a mass fraction of beryllium from 0.0001% to 0.001%), atomic absorption (at a mass fraction of beryllium from 0.002% to 1.0%) and atomic emission with induction plasma (for the mass concentration of beryllium of 0.00005% to 0.01%) methods for determination of beryllium in aluminum casting and wrought alloys.

2 Normative references

The present standard features references to the following standards:

GOST 3118−77 hydrochloric Acid. Specifications

GOST 3652−69 citric Acid monohydrate and anhydrous. Specifications

GOST 3760−79 Ammonia water. Specifications

GOST 4038−79 Nickel (II) chloride 6-water. Specifications

GOST 4204−77 sulfuric Acid. Specifications

GOST 4328−77 Sodium hydroxide. Specifications

GOST 4461−77 nitric Acid. Specifications

GOST 5457−75 Acetylene, dissolved and gaseous. Specifications

GOST 9656−75 boric Acid. Specifications

GOST 10157−79 Argon gaseous and liquid. Specifications

GOST 10484−78 hydrofluoric Acid. Specifications

GOST 10652−73 Reagents. Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid 2-water (Trilon B). Specifications

GOST 10929−76 Hydrogen peroxide. Specifications

GOST 11069−74 Aluminium primary. Brand
_______________
* On the territory of the Russian GOST 11069−2001, here and hereafter. — Note the manufacturer’s database.

GOST 18300−87 ethyl rectified technical. Specifications

GOST 22867−77 Ammonium nitrate. Specifications

GOST 25086−87 non-ferrous metals and their alloys. General requirements for methods of analysis

3 General requirements

3.1 General requirements for methods of analysis GOST 25086 with the Supplement.

3.1.1 the result of the analysis be the arithmetic mean of results of two parallel measurements.

4 Photometric method for the determination of beryllium

4.1 the essence of the method

The method is based on dissolving the sample in a mixture of sulfuric, nitric and hydrochloric acids or sodium hydroxide solution, masking interfering elements with Trilon B, the formation of complex compounds of beryllium with Bellona IV the presence of hexamethylenetetramine and the measurement of the optical density of the solution at a wavelength of 536 nm.

4.2 Equipment, reagents and solutions

Spectrophotometer or photoelectrocolorimeter.

Oven muffle.

Sulfuric acid according to GOST 4204 density 1.84 g/cm, a solution of 1:1.

Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, a solution of 1:1.

Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm.

Hydrofluoric acid according to GOST 10484.

Hydrogen peroxide according to GOST 10929.

Sodium hydroxide according to GOST 4328, a solution of 200 g/cm; is prepared and stored in a plastic container.

Ammonia water according to GOST 3760 density of 0.91 g/cm, a solution of 1:1.

Ammonium nitrate according to GOST 22867, a solution of 10 g/DM.

Nickel (II) chloride 6-water according to GOST 4038, a solution of 2 g/DM.

Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid 2-water (Trilon B) according to GOST 10652, a solution of 100 g/DM.

Hexamethylenetetramine, a solution of 250 g/DM.

The technical rectified ethyl alcohol according to GOST 18300, solution 1:1.

Phenol red indicator solution 1 g/l: 0.1 g of the reagent dissolved in 100 cmof ethanol 1:1.

Berillon IV, a solution of 1 g/DM. If necessary, the solution was filtered through a filter medium density («white ribbon»); cook before eating.

Aluminium GOST 11069 brand А999.

Solution of aluminum was 10 g/DM: 2.5 g of aluminium is placed in a conical flask with a capacity of 250 cmand dissolved in 75 cmof hydrochloric acid under heating, adding 0.5−1 cmof a solution of Nickel chloride (II). The solution was cooled, transferred to a volumetric flask with a capacity of 250 cm, made up to the mark with water and mix.

Beryllium containing not less than 99.9% and beryllium.

Standard solutions of beryllium A, B,

In 5.2.

4.3 analysis

4.3.1 When the mass fraction of silicon is less than 2%

A portion of the sample weight in accordance with table 1 was placed in a conical flask with a capacity of 250 cm, flow 20 cmof sulfuric acid solution, 10 cmof nitric acid, and portions of 10 cmsolution of hydrochloric acid, then the suspension is dissolved under moderate heating. After dissolving, the solution was evaporated until the appearance of white sulphuric acid fumes, cooled, carefully poured water to a volume of 60 cm, pour 5 cmof nitric acid and heated for 3−5 min.


Table 1

4.3.2 When the mass fraction of silicon of more than 2%

A portion of the sample weight in accordance with table 1 was placed in a silver or Nickel a Cup or in a glass made of PTFE, pour 5−6 cmof water, then with constant cooling, in small portions, pour 20 cmof the sodium hydroxide solution. In the process of dissolving a Cup or a glass cover lid. After the cessation of violent reaction solution is gently warmed and added dropwise hydrogen peroxide to completely dissolve the sample. Then the cover and the walls of the Cup or glass should be rinsed with 20−25 cmof water, the solution was evaporated to a thick syrupy consistency, the residue is dissolved under heating in 30 cmof water, cooled, transferred into a low glass with a capacity of 400 cm, with 20 cmof sulfuric acid solution and 5 cmof nitric acid. The solution was evaporated until the appearance of white fumes of sulfuric acid, cooled, the salt is dissolved by heating in 60 cmof water and then pour the 5 cmnitrogen sour

you.

4.3.3 Solution obtained by one of the specified in 4.3.1, 4.3.2 ways, if it is opaque, filtered through a medium density filter (white ribbon) in a beaker with a capacity of 250 cm. The filter cake is washed 6−8 times with hot water (stock solution). The filter with precipitate was placed in a platinum crucible, dried, incinerated, preventing ignition, and calcined at 500−600 °C for 3−5 min. After cooling, to the residue add five drops of sulfuric acid, 5−10 cmhydrofluoric acid and drop by drop nitric acid (approximately 1 cm) to obtain a transparent solution. The solution was evaporated to dryness, poured to the dry residue five drops of sulfuric acid solution, 5−6 cmof hot water and dissolved under moderate heating; the solution is attached to the main solution. If the solution contains the insoluble residue, it is filtered through a dense filter («blue ribbon») of small size in the glass with a basic solution, the filter is 3−4 times washed with hot water.

The resulting solution was cooled to room temperature and transferred to a measuring flask with volume capacity in accordance with table 1, made up to the mark with water and mix.

4.3.4 Aliquot part of the solution in accordance with table 1 was transferred to a beaker with a capacity of 250 cm, in accordance with table 1 flow solutions of aluminum and Trilon B.

In a beaker, with stirring, poured water to a volume of 45−50 cm, add two drops of phenol red solution, dropwise ammonia until you see a red coloring, and then five drops of hydrochloric acid and boiled for 5 min.

The solution was cooled to room temperature, transferred to a volumetric flask with a capacity of 100 cm, flow 10 cmof a solution of berillon IV, 25 cmof a solution of hexamethylenetetramine, made up to the mark with water and mix.

4.3.5 Optical density of the solution is measured after 10 min at a wavelength of 536 nm. Solution comparison is the solution of the reference experiment, which is prepared according to 4.3.1−4.3.4, instead of using the sample samples a portion of the aluminum containing not more than 0.005% of beryllium.

The mass of beryllium is determined by the calibration schedule.

4.3.6 Construction of calibration curve

In eight glasses with a capacity of 250 cmeach poured in 10 cmof a solution of aluminium and 20 cmof a solution of Trilon B for the mass concentration of beryllium of 0.1%; 2 cmof a solution of aluminum and 5 cmof the solution Trilon B for the mass concentration of beryllium of over 0.1 percent.

Seven of them measure 1,0; 2,5; 5,0; 7,5; 10,0; 15,0; 20,0 cmstandard solution, which corresponds to 0,000001; 0,0000025; 0,000005; 0,0000075; 0,00001; 0,000015; 0,00002 g of beryllium. The solutions were diluted with water to a volume of 45−50 cmand then go for 4.3.4 and 4.3.5. Solution not containing beryllium, serves as a solution control experience in construction of calibration curve.

According to the obtained values of optical density of the solutions and their corresponding masses of the beryllium building a calibration curve

.

4.4 Processing of results

4.4.1 Mass fraction of beryllium in % is calculated by the formula

, (1)

whereis the mass of beryllium in the sample solution found by the calibration schedule g;

 — the weight of the portion of the sample in aliquote part of the solution,

4.4.2 discrepancies in the results must not exceed the values given in table 2.


Table 2

Percentage

5 Fluorescent method for the determination of beryllium

5.1 the essence of the method

The method is based on dissolving the samples in hydrochloric acid, bringing the solution pH (13,0±0,2), the formation of complex compounds with by Maureen, fluorescence excitation at a wavelength of 430 nm and measuring the fluorescence of the complex at a wavelength of 520 nm.

5.2 the Instrument, reagents and solutions

a pH meter.

The fluorimeter laboratory «quantum».

Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, a solution of 1:1.

Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm.

Sodium hydroxide according to GOST 4328, solutions of 200 g/DMand 50 g/DM. The solutions were prepared and stored in a plastic container.

Ascorbic acid.

Citric acid according to GOST 3652.

Boric acid according to GOST 9656.

Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid 2-water (Trilon B) according to GOST 10652.

Potassium sanitarily (pyro) or sodium sanitarily (Piro).

A mixture of complexing agents: 80−90 cmof water heated to a temperature of 50−60 °With, successively dissolve 1 g potassium or sodium semitecolo (Piro), 2.5 g ascorbic acid, 2.5 g of citric acid, 5 g of Trilon Trilon B. If B is completely dissolved, then added slowly, dropwise, with stirring, sodium hydroxide solution 200 g/DMuntil dissolved. The solution was cooled to room temperature, add water to volume of 100 cmand mixed. The mixture is prepared the day of use.

The technical rectified ethyl alcohol according to GOST 18300.

Maureen, a solution of 0.2 g/DM: 0.02 g Morin dissolved in 100 cmof ethanol (stock solution). Prior to use 10 cmbasic solution is transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

Buffer solution pH (13,0±0,2): 28,60 g of boric acid dissolved in 500 cmof hot water, transferred into a measuring flask with volume capacity of 1000 cm, pour the sodium hydroxide solution (96 g of sodium hydroxide dissolved in 400 cmof water), cooled to room temperature, made up to the mark with water and mix. the pH of the solution checked for pH meter.

Alizarin blue: 0.1 g of the reagent dissolved in a mixture of 80 cmof ethanol and 20 cmof water.

Aluminium GOST 11069 brand А999.

Beryllium containing not less than 99.9% and beryllium.

Standard solutions of beryllium.

Solution a: 0.1 g of metallic beryllium were placed in a glass with a capacity of 250 cm, flow 50 cmwater 50 cmhydrochloric acid solution and dissolved under moderate heating. After cooling, the solution was transferred into a measuring flask with volume capacity of 1000 cm, made up to the mark with water and mix.

1 cmof the solution contains 0.0001 g of beryllium.

Solution B: 25 cmsolution And transferred to a volumetric flask with a capacity of 250 cm, flow 10 cmof hydrochloric acid, made up to the mark with water and mix.

1 cmof the solution contains 0,00001 g of beryllium.

Solution: 10 cmof a solution transferred to a volumetric flask with a capacity of 100 cm, pour 2 cmof hydrochloric acid, made up to the mark with water and mix. The solution is prepared before use.

1 cmof solution content

it 0,000001 g of beryllium.

5.3 analysis

5.3.1 Sample the sample weight of 0.5 g was placed in a beaker with a capacity of 250 cm, 50 cm pouredhydrochloric acid solution, dissolved under moderate heating, after dissolved add 3−5 drops of nitric acid and evaporated to a volume of 15−20 cm. The solution was cooled, washed the side of the Cup with water, transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix. If the solution is opaque, it is filtered through a dense filter («blue ribbon») in a dry flask, aliquot part of the solution 1 cmtransferred into a measuring flask with a capacity of 25 cm, pour 3−4 cmof water and 2.5 cmof a mixture of complexing agents, five drops of alizarin blue, neutralize the pre-set volume of sodium hydroxide solution 200 g/DM. Then added dropwise a solution of sodium hydroxide 50 g/DMbefore the advent of blue-green color from a single drop of the solution poured 5 cmbuffer solution, 1 cmof the Morin solution, made up to the mark with water and mix.

The fluorescence intensity measured after 5 min, but not later than 50 min in a cuvette with a layer thickness of 20 mm. Solution comparison the solution serves as the reference experiment, which is prepared according to 5.3.1 all used during the analysis reagents.

The mass of beryllium is determined by calibration gr

the Afik.

5.3.2 Construction of calibration curve

In eight glasses with a capacity of 250 cmeach was placed sample of aluminum with a mass of 0.5 g, in seven of them measure 0,5; 1,5; 2,5; 3,5; 5,0; 7,0; 10,0 cmstandard solution, which corresponds to 0,0000005; 0,0000015; 0,0000025; 0,0000035; 0,000005; 0,000007; 0,00001 g of beryllium. The sample is dissolved in 50 cmof a hydrochloric acid solution and then act on 5.3.1.

According to the obtained values of the fluorescence intensity of solutions and their corresponding masses of the beryllium building the calibration curve.

5.4 processing of the results

5.4.1 Mass fraction of beryllium in % is calculated by the formula

, (2)

where is the mass of beryllium in the sample solution found by the calibration schedule g;

 — the weight of the portion of the sample,

5.4.2 the Divergence of results should not exceed the values given in table 3.


Table 3

Percentage

6 Atomic absorption method for the determination of beryllium

6.1 the essence of the method

The method is based on dissolving the samples in hydrochloric acid in the presence of hydrogen peroxide and the atomic absorption measurement of beryllium at a wavelength 234,9 nm in a flame acetylene-nitrous oxide.

6.2 Apparatus, reagents and solutions

Spectrophotometer of atomic absorption with a source of radiation to beryllium.

Oven muffle.

Acetylene according to GOST 5457.

Nitrous oxide medical.

Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, mortar 1:1 and 1:99.

Sulfuric acid according to GOST 4204 density 1.84 g/cm.

Hydrofluoric acid according to GOST 10484.

Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm.

Hydrogen peroxide according to GOST 10929.

Nickel (11) chloride 6-water according to GOST 4038, a solution of 2 g/DM.

Aluminium GOST 11069 brand А999.

A solution of aluminum 20 g/DM: 10 g of aluminum is placed in a conical flask with a capacity of 500 cm, add 300 cmof a hydrochloric acid solution of 1:1 and dissolved by heating, adding 1 cmof a solution of Nickel chloride (II). The solution was cooled, transferred to a volumetric flask with a capacity of 500 cm, made up to the mark with water and mix.

Beryllium containing not less than 99.9% and beryllium.

Standard solutions of beryllium A and B — 5

.2.

6.3 analysis

6.3.1 Sample the sample weighing 1 g is placed in a conical flask with a capacity of 250 cm, 30 cm, pour thewater cautiously, in portions, of 30 cmof a hydrochloric acid solution 1:1. The flask was heated moderately to dissolve the sample, add 3−5 drops of hydrogen peroxide and boiled for 3−5 min.

6.3.1.1 If the solution is clear, it is cooled, transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

6.3.1.2 If residue remains, indicating the presence of silicon, the solution was filtered in a volumetric flask with a capacity of 100 cmthrough a filter medium density («white ribbon»), washed the precipitate on the filter 2−3 times with hot hydrochloric acid 1:99 in portions of 5−10 cm(stock solution).

The filter with precipitate was placed in a platinum crucible, dried, incinerated, preventing ignition, and calcined at 500−600 °C for 3−5 min. After cooling in the crucible add five drops of sulfuric acid, 10 cmhydrofluoric acid and drop by drop nitric acid (approximately 1 cm) to obtain a transparent solution. The solution was evaporated to dryness, cooled, poured to the dry residue 5 cmof hydrochloric acid 1:1 and dissolved under moderate heating. After cooling, the solution is attached to the main solution (if necessary, previously filtered) in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

6.3.2 When the mass fraction of beryllium to 0.05% for atomic absorption measurement using a full solution.

For the mass concentration of beryllium in excess of 0.05% aliquot part of the solution is 5 cm,transferred to a volumetric flask with a capacity of 100 cm, flow 10 cmof hydrochloric acid 1:1, made up to the mark with water and mix.

6.3.3 Solution of the reference experiment is prepared in 6.3.1, 6.3.2, using is sample the sample the sample of aluminium.

6.3.4 Construction of calibration graphs

6.3.4.1 When the mass fraction of beryllium from 0.002% to 0.05%

In seven volumetric flasks with a capacity of 100 cmeach poured in 50 cmof a solution of aluminium and three of them measure 2,0; 5,0 and 7,5 cmstandard solution B, and in the next three to 1.0, 2.5 and 5.0 cmstandard solution A, which corresponds to 0,00002; 0,00005; 0,000075; 0,0001; 0,00025; 0,0005 g of beryllium.

6.3.4.2 When the mass fraction of beryllium in excess of 0.05%

In six volumetric flasks with a capacity of 100 cmeach pour 2.5 cmof a solution of aluminum 10 cmof hydrochloric acid 1:1 and in five of them measure 0,5; 1,0; 2,0; 4,0; 5,0 cmstandard solution A, which corresponds to 0,00005; 0,0001; 0,0002; 0,0004; 0.0005 g of beryllium.

6.3.4.3 Solutions obtained by 6.3.4.1, 6.3.4.2, made up to the mark with water and mix.

6.3.5 Solutions of the samples in the reference experiment and the solutions for constructing the calibration curve is sprayed into the flame of acetylene-nitrous oxide and measure the atomic absorption of beryllium at a wavelength 234,9 nm.

According to the obtained values of atomic absorption and corresponding mass concentrations of beryllium to build a calibration curve in the coordinates: «the Value of atomic absorption — mass concentration of beryllium in g/cm». A solution in which the beryllium is not introduced serves as a solution control experience in construction of calibration curve.

The mass concentration of beryllium in the sample solution and the solution of control and experience determined by the calibration schedule.

6.4 Processing of results

6.4.1 Mass fraction of beryllium in % is calculated by the formula

, (3)

where is the mass concentration of beryllium in the sample solution found by the calibration schedule, g/cm;

 — mass concentration of beryllium in solution in the reference experiment, was found in the calibration schedule, g/cm;

 — the volume of the sample solution, cm;

 — the weight of the portion of the sample or the weight of the portion of the sample in aliquote part of the solution, g

.

6.4.2 Divergence of results should not exceed the values given in table 4.


Table 4

Percentage

7 Atomic-emission method for the determination of beryllium with an induction plasma

7.1 the essence of the method

The method is based on dissolving the samples in hydrochloric acid in the presence of hydrogen peroxide, spraying the solution into the induction plasma torch, measuring the intensity of radiation of beryllium at a wavelength 234,8 nm.

7.2 Apparatus, reagents and solutions

Spectrum analyzer with induction plasma (monochromator, polychromator).

Oven muffle.

Argon according to GOST 10157 grade A.

Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, the solutions of 1:1, 1:99.

Sulfuric acid according to GOST 4204 density 1.84 g/cm.

Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm.

Hydrofluoric acid according to GOST 10484.

Hydrogen peroxide according to GOST 10929.

Nickel (II) chloride 6-water according to GOST 4038, a solution of 2 g/DM.

Aluminium GOST 11069 brand А999.

Solution of aluminum 20 g/l, prepared according to 6.2.

Beryllium containing not less than 99.9% and beryllium.

Standard solutions of beryllium.

Solutions A, B, C — 5.2.

Solution G: 10 cmsolution is transferred to a volumetric flask with a capacity of 100 cm, pour 2 cmof hydrochloric acid 1:1, made up to the mark with water and mix.

1 cmof the solution contains of 0.0000001 g of beryllium.

Solutions C and d were prepared before receiving a

eat.

7.3 analysis

7.3.1 a portion of the sample weighing 0.5 g is placed in a conical flask with a capacity of 250 cm, flow 20 cmof water, 20 cmof a hydrochloric acid solution 1:1, cover the flask with a watch glass or funnel and moderately heated to dissolve the sample. Then remove watch glass or funnel, pour 1 cmof hydrogen peroxide, washed the walls of the bulb 20 cmof water, mix and boil the solution for 3−5 min.

7.3.1.1 If the solution is clear, it is cooled, transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

7.3.1.2 If there is a precipitate, indicating the presence of silicon, the solution was filtered in a volumetric flask with a capacity of 100 cmthrough a filter medium density («white ribbon»), washed the precipitate on the filter 2−3 times with hot hydrochloric acid 1:99 in portions of 5−10 cm(stock solution).

The filter with precipitate was placed in a platinum crucible, dried, incinerated, preventing ignition, and calcined at 500−600 °C for 3−5 min. After cooling in the crucible add five drops of sulfuric acid, 10 cmhydrofluoric acid and drop by drop nitric acid (approximately 1 cm) to obtain a transparent solution. The solution was evaporated to dryness, cooled, poured to the dry residue 5 cmof hydrochloric acid 1:1 and dissolved under moderate heating. After cooling, the solution is attached to the main solution (if necessary, previously filtered) in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

7.3.2 Solution of the reference experiment is prepared in accordance with 7.3.1, using is sample the sample the sample of aluminium.

7.3.3 Construction of calibration graphs

7.3.3.1 for the mass concentration of beryllium of 0.00005% to 0.001%

In seven volumetric flasks with a capacity of 100 cmeach poured in 25 cmof a solution of aluminum and two of them measure 2,5; 5,0 cmstandard solution G, in the following four — 1,0; 2,0; 3,0; 5,0 cmstandard solution, which corresponds to 0,00005; 0,0001; 0,0002; 0,0004; 0,0006; 0,001% beryllium.

7.3.3.2 When the mass fraction of beryllium from 0.001% to 0.01%

In seven volumetric flasks with a capacity of 100 cmeach poured in 25 cmof a solution of aluminum in six of them measure 0,5; 1,0; 2,0; 3,0; 4,0; 5,0 cmstandard solution B, which corresponds to 0,001; 0,002; 0,004; 0,006; 0,008; 0,01% beryllium.

7.3.3.3 Solutions obtained in 7.3.3.1 and 7.3.3.2, made up to the mark with water and mix.

7.3.4 Solutions of the samples in the reference experiment and the solutions for constructing the calibration curve is sprayed into the plasma torch to measure the signal of the atomic emission at a wavelength 234,8 nm. Before each sample measurement, the system was washed with hydrochloric acid 1:99.

According to the obtained values of the signals of the atomic emission calibration mixtures, less signal solution in which the beryllium is not entered, build a calibration curve in the coordinates: «the Value of atomic emission — mass fraction of beryllium per cent."

7.4 processing of the results

7.4.1 Mass fraction of beryllium in % is determined according to the calibration schedule using the difference between the values of the atomic emission signals in the sample solution and the solution in the reference experiment.

7.4.2 discrepancies in the results must not exceed the values given in table 5.


Table 5

Percentage