GB/T 38812.3-2020 Direct reduced iron—Determination of silicon,manganese,phosphorus,vanadium,titanium,copper,aluminum,arsenic,magnesium,calcium,potassium and sodium content—Inductively coupled plasma atomic emission spectrometric method

GB/T 38812.1-2020 Direct reduced iron—Determination of iron(Ⅱ) content—The potassium dichromate titrimetric method after decomposition of sample by ferric chloride GB/T 38812.2-2020 Direct reduced iron—Determination of metallic iron content—The potassium dichromate titrimetric method after decomposition of sample by ferric chloride

GB/T 6682-1992 Water for analytical laboratory use—Specification and test methods GB/T 6682-2008 Water for analytical laboratory use—Specification and test methods GB/T 8170-1987 Rules for rounding off of numberical values GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgement of limiting values GB/T 12806-1991 Laboratory glassware—One-mark volumetric flasks GB/T 12806-2011 Laboratory glassware—One-mark volumetric flasks GB/T 12807-1991 Laboratory glassware—Graduated pipettes GB/T 12807-2021 Laboratory glassware—Graduated pipettes GB/T 12808-1991 Laboratory glassware—One-mark pipettes GB/T 12808-2015 Laboratory glassware—One mark pipettes GB/T 24239-2009 Direct reduced iron and hot briquetted iron—Sampling and sample preparation