71.080.30 – Organic nitrogen compounds – PDF Standards Store ?u= Wed, 06 Nov 2024 02:30:46 +0000 en-US hourly 1 https://wordpress.org/?v=6.7.1 ?u=/wp-content/uploads/2024/11/cropped-icon-150x150.png 71.080.30 – Organic nitrogen compounds – PDF Standards Store ?u= 32 32 JIS K 1531:2003 ?u=/product/publishers/jis/jis-k-15312003/ Wed, 06 Nov 2024 02:30:46 +0000 Melamine
Published By Publication Date Number of Pages
JIS 2003-02-20 11
]]> Melamine
Published By Publication Date Number of Pages
JIS 2003-02-20 11
]]> ISO/R 1595:1970 ?u=/product/publishers/iso/iso-r-15951970/ Wed, 06 Nov 2024 01:07:54 +0000 Urea for industrial use — Determination of iron content — 2,2'- Bipyridyl photometric method
Published By Publication Date Number of Pages
ISO 1970-07 6
]]> Describes a method applicable to iron contents greater than or equal to 0.00005 % (m/m). The principle is based on the ignition of the material at 800 °C and fusion of the residue with anhydrous potassium hydrogen sulphate. Solution of the cooled melt in hydrochloric acid and reduction of iron(III) by means of hydroxylammonium chloride. Formation of an iron(II)-2,2'bipyridyl complex in the presence of a buffered solution (pH value between 4.5 and 6). Photometric measurement of the coloured complex at a wavelength of about 522 nm.

]]> ISO 8661:1988 ?u=/product/publishers/iso/iso-86611988/ Wed, 06 Nov 2024 00:15:19 +0000 Caprolactam for industrial use — Determination of volatile bases content — Titrimetric method after distillation
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ISO 1988-05 6
]]> The volatile bases are distilled in alkaline medium under specified conditions and collected in a known volume of a standard volumetric hydrochloric acid solution in the presence of an indicator. The excess of the acid is titrated with a standard volumetric sodium hydroxide solution.

]]> ISO 8660:2002 ?u=/product/publishers/iso/iso-86602002/ Wed, 06 Nov 2024 00:15:19 +0000 Plastics — Determination of permanganate absorption number of caprolactam — Spectrometric method
Published By Publication Date Number of Pages
ISO 2002-05 14
]]> This International Standard specifies a spectrometric method for the determination of the permanganate absorption number of caprolactam for industrial use. The permanganate absorption number is a measure of the oxidizable impurities in caprolactam, determined in a buffered neutral aqueous medium under fixed conditions.

The method is applicable to purified caprolactam (and intermediates in the caprolactam purification process) with an alkalinity or acidity lower than 0,50 mmol/kg and a PAN value of up to 35.

]]> ISO 8112:1984 ?u=/product/publishers/iso/iso-81121984/ Wed, 06 Nov 2024 00:06:31 +0000 Caprolactam for industrial use — Determination of colour of 50 % aqueous caprolactam solution, expressed in Hazen units (platinum-cobalt scale) — Spectrometric method
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ISO 1984-11 4
]]> The absorbance of a 50 % aqueous caprolactam solution is spectrometrically measured at a wavelength of 390 nm and an optical path length of 50 mm. The result is expressed in Hazen units by multiplying the absorbance measured by a constant factor equal to 150. This factor is derived from measurements of absorbance of diluted standard solutions of platinum-cobalt scale.

]]> ISO 7060:1982 ?u=/product/publishers/iso/iso-70601982/ Tue, 05 Nov 2024 23:51:03 +0000 Caprolactam for industrial use — Determination of crystallizing point
Published By Publication Date Number of Pages
ISO 1982-12 3
]]> A sample of liquid caprolactam, or a liquefied sample of crystalline caprolactam is cooled and the temperature at which crystallization occurs is observed.

]]> ISO 7059:1982 ?u=/product/publishers/iso/iso-70591982/ Tue, 05 Nov 2024 23:51:02 +0000 Caprolactam for industrial use — Determination of absorbance at a wavelength of 290 nm
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ISO 1982-12 3
]]> The spectrometric measurement of the absorbance of a 50 % caprolactam water solution is carried out at a wavelength of 290 nm. The absorbance, expressed in relation to an optical path length of 1 m, is given by a specified formula in which AO is the correction for the difference in absorbances of the cells; A1 is the absorbance of the test solution, and 1 is the optical path length, in centimetres, of the cell.

]]> ISO 4274:1977 ?u=/product/publishers/iso/iso-42741977/ Tue, 05 Nov 2024 23:17:50 +0000 Urea for industrial use — Determination of biuret content — Flame atomic absorption and photometric absorption methods
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ISO 1977-10 8
]]> Applicable to products having contents of equal to or more than 0.05 % (m/m) (with flame atomic absorption) or 0.1 % (m/m) (with fotometric absorption). Covers the formation of a complex between biuret and copper(II) sulphate in alkaline medium. Fixation of this complex on an anion exchange resin. Elution of Cu first with a potassium nitrate solution and then with a nitric acid solution. Flame atomic absorption: aspiration of the solution into an acetylene-air flame and measurement of the absorption of the 325-nm line emitted by a copper hollow-cathode lamp; or by photometric absorption: formation of a coloured complex between Cu and zinc dibenzyldithiocarbamate, extraction with carbon tetrachloride and measurement at a wavelength of about 435 nm. Has also been approved by the IUPAC.

]]> ISO 2754:1973 ?u=/product/publishers/iso/iso-27541973/ Tue, 05 Nov 2024 22:54:18 +0000 Urea for industrial use — Determination of biuret content — Photometric method
Published By Publication Date Number of Pages
ISO 1973-12 5
]]> Applicable to the determination in the presence of ammoniacal salts less than 15 mg in the aliquot amount taken for the determination. In the presence of quantities exceeding 15 mg the ammoniacal nitrogen shall be removed by a cation exchange resin because these salts interfere with the determination. The principle of the reaction consists in formation of a violet-red complex between allophanic acid amide (H2 N.CO.NH.CO.NH2 ) and copper sulphate in the presence of an alkaline solution of potassium sodium tartrate. Photometric measurement at a wavelength of about 550 nm. Has also been approved by the IUPAC.

]]> ISO 2753:1973 ?u=/product/publishers/iso/iso-27531973/ Tue, 05 Nov 2024 22:54:17 +0000 Urea for industrial use — Determination of water content — Karl Fischer method
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ISO 1973-12 3
]]> Specifies the manner in which this method is to be applied in a reaction of any water present in urea with a solution of iodine and sulphur dioxide in a mixture of pyridine and methanol (Karl Fischer reagent). This reagent is first standadized by titration with a precisely known mass of water. The end point of the reaction is read by the direct visual or direct electrometric method. The method has also been approved by the IUPAC.

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