ISO 11723:2016 pdf free download.Solid mineral fuels Determination of arsenic and selenium Eschka’s mixture and hydride generation method
Combustibles minéraux solides — Dosage de l’arsenic et du sélénium— Mélange d’Eschka et méthode par production d’hydrure.
5.4 Potassium iodide solution, 500 g/l. Dissolve 50 g of analytical reagent (AR) grade Kl in distilled water and adjust the volume to 100 ml (for determination of As).
5.5 Sodium borohydride solution. Weigh 1,50 g of sodium borohydride (NaBH4) and 0,4 g of sodium hydroxide (NaOH) into a plastic bottle of 125 ml capacity and add 100 ml of distilled water. Prepare freshly on the day of use. Alternatively, commercially available pressed pellets of sodium borohydride may be used.
5.6 Arsenic stock solution (100 mg/i). Dissolve 0,132 0 g ± 0,000 5 g of arsenic trioxide (As203 of 99,9 % purity, dried at 110 °C for 1 h) in 25 ml of 20 % KOH solution. Add approximately 50 ml of water and 20 ml of hydrochloric acid (52). Adjust the volume with water to 1 litre in a volumetric flask. Alternatively, dissolve 0,416 5 g ± 0,000 5 g of sodium arsenate (Na2HAsO4.7H20) in approximately 100 ml of water. Add 10 ml of hydrochloric acid (52) and adjust the volume with water to 1 1 in a volumetric flask.
NOTE A commercially available certified stock solution may be used as an alternative.
5.7 Dilute arsenic stock solution (1 mg/i). Transfer 5 ml of arsenic stock solution to a 500 ml volumetric flask. Add approximately 100 ml of water and 5 ml of hydrochloric acid (52). Adjust to volume with water.
5.8 Arsenic working standard (50 .tg/l). Transfer 5 ml of dilute arsenic stock solution (52) to a
100 ml volumetric flask. Add approximately 20 ml of water and of 1 ml hydrochloric acid (52). Adjust to
volume with water. Prepare freshly on the day of measurement.
5.9 Selenium stock solution (100 mg/i). Dissolve 0,100 0 ± 0,000 5 g of elemental selenium (of 99,9% purity) in a minimum of nitric acid in a beaker. Evaporate to dryness. Add 2 ml of water and evaporate to dryness; repeat this procedure twice. Add 10 ml of water to the residue and 10 ml of hydrochloric acid (5.2). Dissolve the residue by heating. Allow the solution to cool and adjust the volume with water to 1 1 in a volumetric flask. Alternatively, dissolve 0,467 4 g ± 0,000 5 g of sodium selenate (Na2SeO4.10H20) in approximately 100 ml of water. Add 10 ml of hydrochloric acid (5.2) and adjust the volume with water to 1 1 in a volumetric flask.
NOTE A commercially available certified stock solution may be used as an alternative.
5.10 Dilute selenium stock solution (1 mg/I). Transfer 5 ml of selenium stock solution (5±9) to a
500 ml volumetric flask. Add approximately 100 ml of water and 5 ml of hydrochloric acid (52). Adjust
to volume with water.
5.11 Selenium working standard (50 ig/l). Transfer 5 ml of dilute selenium stock solution (5.10) to a
100 ml volumetric flask. Add approximately 20 ml of water and 1 ml of hydrochloric acid (52). Adjust to
volume with water. Prepare freshly on the day of measurement.ISO 11723:2016 pdf free download.
Tags: Solid mineral fuels
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ISO 8600-1-2013 pdf free download.Endoscopes – Medical endoscopes and endotherapy devices – Part 1: General requirements. 6 Marking 6.1 Minimum marking Iach individual endoscope or endotherapy device shall have the lollowing minimum marking: a) model number and/or other mark sufficient to identify the endoscope or endotherapy device and its manufacturer; b) maximum insertion portion width, minimum instrument channel width, working length, field of view and/or direction of view where such identification is necessary for the intended use of the endoscope or endotherapy device. The Insertion portion width and instrument channel width units shall be in millimetres. The insertion portion width and instrument channel width can also be marked in French size as defined in 3.5, shown by either ‘Fr or an encircled number; c) wherever reasonable and practicable. the endoscope or endotherapy device and detachable component(s) shall be identified in terms of lot numbers or serial numbers, etc. 6.2 Marking legibility The marking shall remain legible over the lifetime of the device when the endoscope or endotherapy device is used, cleaned, disinlected, sterilized and stored in accordance with the instruction manual. 6.3 Marking exceptions When marking on the endoscope or endotherapy device or detachable component(s) is impossible to achieve due…
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ISO 15688-2012 pdf free download.Road construction and maintenance equipment – Soil stabilizers 一 Terminology and commercial specifications. This International Standard establishes the terminology, definitions of operation and commercial specifications for soil stabilizers and their components intended for use in road construction and pavement works. It does not apply to soil stabilizers used in agricultural applications. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.. ISO 3911, Wheels and rims for pneumatic tyres — Vocabulary, designation and marking ISO 6746-1, Earth-moving machinery — Definitions of dimensions and codes — Part 1: Base machine ISO 6746-2, Earth-moving machinery — Definitions of dimensions and codes — Part 2: Equipment and attachments ISO 7134. Earth-moving machinery — Graders — Terminology and commercial specifications 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 soil stabilizer self-propelled machine, either towed or transported, with the function of pulverizing, breaking-up, aerating, homogenizing, and loosening existing and imported soil or paving materials and mixing them…
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ISO 18436-1-2012 pdf free.Condition monitoring and diagnostics of machines – Requirements for qualification and assessment of personnel一 Part 1: Requirements for assessment bodies and the assessment process. 5 Requirements for assessment body personnel 5.1 General provisions In order to ensure that the assessment process is carried out effectively and uniformly, the competence requirements for personnel involved in the entire process shall be defined by the assessment body and, in the case of a third party, be approved by the responsible TCC (in accordance with ISO/IEC 17024). The assessment body shall require its personnel (internal or external) to sign a contract, or other document, by which they commit themselves to comply with the rules defined by the assessment body, including those relating to confidentiality and those relating to independence from commercial and other interests, and from any prior or present link with the persons to be examined that would, in the opinion of the interested parties, compromise impartiality. Clearly documented instructions shall be available to the personnel, describing their duties and responsibilities. These instructions shall be maintained up to date. All personnel involved in any aspect of assessment activities shall possess appropriate educational qualifications, experience and technical expertise, which satisfy defined…