SJ 1591-1980 Analysis method of thorium oxide and rhenium in thoriated tungsten-rhenium wire for vacuum devices SJ1591-1980 standard download decompression password: www.bzxz.net

Standard of the Fourth Machinery Industry Department of the People's Republic of China
Analysis method of oxidation in tungsten wire for electric vacuum device body
SJ1591--80
SJ1591—80
In 1.4: the boiling point in solution
should be changed to
In 2.3, the third line: after precipitation and condensation
3.2h, the second line of the second line is transferred to 25 ml
In the calculation formula, TnO2
should be changed to
should be changed to||tt ||Should be changed to
Boil the solution
After the precipitation condenses
Transfer to 250 ml
Ministry of Industry of the Fourth Machinery Industry City of the People's Republic of China
Analysis method of oxide and in tungsten wire for vacuum devices
1. General,
1.1. This method is applicable to the determination of oxide and in tungsten wire for vacuum devices, SJ159180
1.2. The purity of the reagents used in the analysis shall not be less than analytical grade (secondary) except those specified. 1.3. Distilled water or water of equivalent purity shall be used in the analysis, 1.4. Sample treatment:
The wire material is boiled in 20% sodium hydroxide solution for about 15 minutes, washed with water, and the residual milk is removed with gauze or filter paper. Cut into appropriate length (usually not more than 2 widths), soak in 1+1 hydrochloric acid for a while, mill with water and then dehydrate with anhydrous ethanol.
2. Determination of tungsten oxide
2.1. Key points of the method
The sample is dissolved in hydrofluoric acid and nitric acid, separated from tungsten in the form of hydrogenation and other precipitations, and burned to constant weight. 2.2. Required reagents:
a, hydrofluoric acid (concentrated)
b, nitric acid
(concentrated)
c. ammonium hydrocyanide (1-1)
e. anhydrous ethanol (concentrated)
2.3. Test method:
Weigh 0.5 g of the sample (accuracy is ±0.0002 g) in a platinum dish Add 10-15 liters of FuFluorine, drop nitric acid to dissolve the sample, and transfer to a water bath for heating after the intense reaction stops. After the sample is completely dissolved and slowly precipitated, dilute with one-fold hot water, let it stand for a while, filter it on a plastic funnel with a double-counter tight filter (or one-fold filter paper plus paper pulp), wash the precipitate with 1:1 hot ammonia water 20-30 times (the filtrate volume is about 100 ml), and then wash it with hot water 2-3 times (the filtrate and washing liquid are collected in a platinum dish and evaporated to dryness for measurement), transfer the precipitate and the filter paper into a constant weight platinum solution for ash, and burn it at 900℃ to constant weight. Calculation formula: Tno: =
W×100-·100%
Implementation on January 1, 1981
#2 Page 2
W-precipitate weight in grams,
G-test weight in grams.
3. Determination of red:
SJ1591-80
3.1. According to the method, the sample is dissolved in hydrochloric acid and nitric acid, and after the red is separated, it is reduced to low red in hydrochloric acid solution and then forms a stable color complex with hydrogen sulfide for colorimetric determination. 3.2. Required reagents and instruments: a. Phosphoric acid (concentrated): b. Hydrogen acid (concentrated): c. Sodium chloride (50% aqueous solution): d. Hydrochloric acid 1:1 (concentrated): e. Sodium chloride: 10%, 10 g SaCl, dissolved in 50 liters of concentrated hydrochloric acid, diluted with water to 100 ml: f. NaHCO3: 8N: f. Sodium thiosulfate: 10% aqueous solution: h. Standard solution of tungsten at 2 g/ml: Dissolve 0.5 g tungsten powder in platinum, dissolve it with hydrofluoric acid and nitric acid dropwise, evaporate to near dryness, dissolve it with a small amount of vaporizer, transfer to 25 liters of volumetric paint, dilute to the scale with water, and mix well.
i. Dye standard solution: 1 mg/ml:
Weigh 0.1000 g of long powder (purity of 99.9% or more), or 0.144 g of ammonia, dissolve it with nitric acid, then evaporate the nitric acid in a water bath (below 80°C), dissolve the residue with water, put it into a 100-liter volumetric flask, and make sure that the water drops to the scale and mix well.
j. Colorimeter: 72 type;
Wavelength: 470 microns; wwW.bzxz.Net
Colorimetric m: 3 cm,
8.8. Determination method
Evaporate the filtrate of the determination of dioxygen to dryness, dissolve a small amount of sodium hydroxide with slight heat, transfer the solution into a 200-liter container, dilute to the scale, and mix well. Take 5 liters of the above solution in a 50-ml volumetric flask and add 5 liters of tartaric acid. 20 liters of taurine, 2.5 ml of potassium thiocyanate, 2 ml of stannous chloride, dilute to the mark with water, shake thoroughly, perform colorimetry after 30 minutes, and draw a standard curve at the same time. Drawing of the standard curve: In a 50 ml volumetric flask, add tungsten standard solution: 0:0.1, 0.2:0.3; 0.4:0.5; mg, add 5 liters of tungsten standard solution, and the following operations are the same as the previous sample.
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