At what temperature does n2 decompose?
At what temperature does n2 decompose?, Total:116 items.
The international standard classification for "At what temperature does n2 decompose?" includes: Other materials for the reinforcement of composites , Protection against dangerous goods , Iron ores , Man-made fibres , Aerospace engines and propulsion systems , Materials for aluminium production .
The Chinese standard classification for "At what temperature does n2 decompose?" includes: Other non-metal mine product , Marking, packaging, transport and storage in general , Asbestos material , Iron ore , Chemical fibre in general , Spacecraft power system , Metal physical property test method , Petroleum products in general .
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
- GB/T 8073-1987 Method of wet determination for loftiness of chrysotile asbestos
- GB/T 21613-2008 Dangerous goods - Test method for determination of the accelerating decomposition temperature
- GB/T 31850-2015 Test method for thermogravimetry(TG) of no-matallic sealing materials
- GB/T 30711-2014 Test method for thermogravimetry(TG)of friction materials
- GB/T 22052-2008 Test method for vapor pressure - Temperature relationship and initial decompostition temperature of liquids by isoteniscope
- GB/T 31923.2-2015 Iron ores for blast furnace feedstocks―Determination of low-temperature reduction-disintegration indices by static method―Part 2:Reduction with CO and N2
工业和信息化部
- HG/T 5841-2021 Chlorinated Paraffins-Determination of Thermal Decomposition Temperature
国家市场监督管理总局、中国国家标准化管理委员会
- GB/T 37631-2019 Man-made fiber—Test method for thermal decomposition temperature
Professional Standard - Aerospace
- QJ 1468-1988 Test Methods for Initial Thermal Decomposition Temperature and Off Temperature of Composite Solid Propellant
中华人民共和国国家质量监督检验检疫总局、中国国家标准化管理委员会
- GB/T 33908-2017 Technical specification for testing of liquidus temperature of the electrolyte
Professional Standard - Petrochemical Industry
- SH/T 0561-1993 Determination method for thermal decomposition temperature of anti-oxidant and anti-corrosive additive (capillary method)
SCC
- AWWA ACE94053 What is the Turbidity of Your Files?
- 05/30132135 DC ISO 4696-2. Iron ores for blast furnace feedstocks. Determination of low-temperature reduction-disintegration indices by static method. Part 2. Reduction with CO and N2
- SPC GB/T 37631-2019 Man-made fiber -- Test method for thermal decomposition temperature (TEXT OF DOCUMENT IS IN CHINESE)
- 05/30132129 DC ISO 4696-1. Iron ores for blast furnace feedstocks. Determination of low-temperature reduction-disintegration indices by static method. Part 1. Reduction with CO, CO2, H2 and N2
- DIN EN 2923 E:2018 Draft Document - Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification: 600 MPa (at ambient temperature)/ 425° C; German and English version FprEN 2923:2018
- NS-EN 4069:1996 Aerospace series — Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, passivated — Classification: 600 MPa (at ambient temperature)/650°C
- AS 1684.2 N1/N2 Supp 4:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 4: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade MGP 10 (Supplement to AS 1684.2-2010)
- AS 1684.2 N1/N2 Supp 7:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 7: Timber framing span tables - Wind classification N1/N2 - WA seasoned hardwood - Stress Grade F14, (Supplement to AS 1684.2-2010)
- DIN EN 2924 E:2018 Draft Document - Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated, left hand thread - Classification 600 MPa (at ambient temperature)/ 425° C; German and English version FprEN 2924:2...
- AS 1684.2 N1 N2 SUPP 5:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 5: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress grade MGP 12 (Supplement to AS 1684.2-1999)
- AS 1684.2 N1 N2 SUPP 1:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 1: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress grade F5 (Supplement to AS 1684.2-1999)
- MIL MIL-I-3848A-1963 INDICATOR, PROPELLANT TEMPERATURE, M13, M15 AND M33 (LESS PROPELLANT) (SUPERSEDING MIL-I-3848)
- AS 1684.2 N1 N2 SUPP 2:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 2: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade F7 (Supplement to AS 1684.2-2006)
- AS 1684.2 N1 N2 SUPP 2:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 2: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress grade F7 (Supplement to AS 1684.2-1999)
- AS 1684.2 N1 N2 SUPP 13:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 13: Timber framing span tables - Wind classification N1/N2 - Unseasoned hardwood - Stress Grade F11 (Supplement to AS 1684.2-2006)
- AS 1684.2 N1 N2 SUPP 5:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 5: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade MGP 12 (Supplement to AS 1684.2 - 2010)
- AS 1684.2 N1 N2 SUPP 14:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 14: Timber framing span tables - Wind classification N1/N2 - Unseasoned hardwood - Stress Grade F14 (Supplement to AS 1684.2-2006)
- AS 1684.2 N1 N2 SUPP 9:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 9: Timber framing span tables - Wind classification N1/N2 - Seasoned hardwood - Stress grade F27 (Supplement to AS 1684.2-1999)
- AS 1684.2 N1/N2 Supp 2:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 2: Timber framing span tables - Wind classification, N1/N2 - Seasoned softwood - Stress Grade F7 (Supplement to AS 1684.2-2010)
- AS 1684.2 N1/N2 Supp 8:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 8: Timber framing span tables - Wind classification, N1/N2 - Seasoned hardwood - Stress Grade F17 (Supplement to AS 1684.2-2010)
- DIN EN 3742 E:1992 Draft Document - Aerospace series; nuts, hexagonal, slotted/castellated reduced height, reduced across flats, in heat resisting steel, passivated; classification: 600 MPa (at ambient temperature)/650 °C
- MIL MIL-DTL-6669D-2011 Indicator, Temperature, Electrical Resistance, Multi-Function, -70 Degrees C to +150 Degrees C
- AS 1684.2 N1 N2 SUPP 5:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 5: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade MGP 12 (Supplement to AS 1684.2-2006)
- AS 1684.2 N1 N2 SUPP 4:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 4: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade MGP 10 (Supplement to AS 1684.2-2006)
- AS 1684.2 N1/N2 Supp 9:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 9: Timber framing span tables - Wind classification, N1/N2 - Seasoned hardwood - Stress Grade F27 (Supplement to AS 1684.2-2010)
- AS 1684.2 N1/N2 Supp 1:2010 Residential timber-framed construction, Part 2: Non-cyclonic areas, N1/N2 Supplement 1: Timber framing span tables - Wind classification, N1/N2 - Seasoned softwood - Stress Grade F5 (Supplement to AS 1684.2-2010)
- AS 1684.2 N1 N2 SUPP 13:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 13: Timber framing span tables - Wind classification N1/N2 - Unseasoned hardwood - Stress Grade F11 (Supplement to AS 1684.2-1999)
- AS 1684.2 N1 N2 SUPP 6:1999 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 6: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress grade MGP 15 (Supplement to AS 1684.2-1999)
- DIN EN 2922 E:1997 Draft Document - Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, passivated, left hand thread; Classification: 600 MPa (at ambient temperature)/650 °C
- AS 1684.2 N1 N2 SUPP 6:2006 Residential timber-framed construction, Part 2: Non-cyclonic areas - N1/N2 Supplement 6: Timber framing span tables - Wind classification N1/N2 - Seasoned softwood - Stress Grade MGP 15 (Supplement to AS 1684.2-2006)
GSO
- OS GSO ISO 4696-2:2013 Iron ores for blast furnace feedstocks -- Determination of low-temperature reduction-disintegration indices by static method -- Part 2: Reduction with CO and N2
- BH GSO ISO 12268:2017 Aerospace -- Nuts, hexagonal, plain, reduced height, reduced across flats, with MJ threads, classifications: 450 MPa (at ambient temperature)/425 degrees C, 600 MPa (at ambient temperature)/235 degrees C, 600 MPa (at ambient temperature)/315 degrees C,...
- GSO ISO 12268:2015 Aerospace -- Nuts, hexagonal, plain, reduced height, reduced across flats, with MJ threads, classifications: 450 MPa (at ambient temperature)/425 degrees C, 600 MPa (at ambient temperature)/235 degrees C, 600 MPa (at ambient temperature)/315 degrees C,...
- OS GSO ISO 12268:2015 Aerospace -- Nuts, hexagonal, plain, reduced height, reduced across flats, with MJ threads, classifications: 450 MPa (at ambient temperature)/425 degrees C, 600 MPa (at ambient temperature)/235 degrees C, 600 MPa (at ambient temperature)/315 degrees C,...
- BH GSO ISO 4696-1:2016 Iron ores for blast furnace feedstocks -- Determination of low-temperature reduction-disintegration indices by static method -- Part 1: Reduction with CO, CO2, H2 and N2
- BH GSO ISO 10096:2017 Aerospace -- Nuts, hexagonal, slotted (castellated), reduced height, reduced across flats, with MJ threads, classifications: 450 MPa (at ambient temperature)/425 degrees C, 600 MPa (at ambient temperature)/235 degrees C, 600 MPa (at ambient temperature)/
ASHRAE - American Society of Heating@ Refrigerating and Air-Conditioning Engineers@ Inc.
- ASHRAE QC-06-046-2006 Air Quality in Transportation Cabins - Part I: How Much Do We Know About it?
- ASHRAE 3694-1993 Demonstration of a High- Temperature Heat Pump for Minimizing Liquid Indutrial Waste
- ASHRAE SE-99-13-04-1999 Comparison of Coupled and Decoupled Solutions for Temperature and Air Flow in a Building
Korean Agency for Technology and Standards (KATS)
- KS E ISO 4696-2:2022 Iron ores for blast furnace feedstocks — Determination of low-temperature reduction-disintegration indices by static method — Part 2: Reduction with CO and N2
- KS E ISO 4696-1-2022 Iron ores for blast furnace feedstocks-Determination of low-temperature reduction-disintegration indices by static method-Part 1:Reduction with CO, CO2, H2 and N2
- KS E ISO 4696-1-2017(2022) Iron ores for blast furnace feedstocks-Determination of low-temperature reduction-disintegration indices by static method-Part 1:Reduction with CO, CO2, H2 and N2
- KS C 0076-1990 Methods for determining distribution temperature and colour temperature or correlated co1our temperature of light sources
KR-KS
- KS E ISO 4696-2-2022 Iron ores for blast furnace feedstocks — Determination of low-temperature reduction-disintegration indices by static method — Part 2: Reduction with CO and N2
- KS E ISO 4696-1-2017 Iron ores for blast furnace feedstocks-Determination of low-temperature reduction-disintegration indices by static method-Part 1:Reduction with CO, CO2, H2 and N2
ES-AENOR
- INTA 15 02 07 Functional viscosity. thermographic method
AENOR
- UNE-EN 4069:1996 AEROSPACE SERIES. NUTS, HEXAGON, PLAIN, REDUCED HEIGHT, REDUCED ACROSS FLATS, IN HEAT RESISTING STEEL, PASSIVATED. CLASSIFICATION: 600 MPA (AT AMBIENT TEMPERATURE)/650 oC.
German Institute for Standardization
- DIN EN 2923:2019-07 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification: 600 MPa (at ambient temperature)/425 °C; German and English version EN 2923:2019
- DIN EN 4069:1996-03 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, passivated - Classification: 600 MPa (at ambient temperature)/650 °C; German version EN 4069:1996
- DIN 53436-1:2015 Generation of thermal decomposition products from materials for their analytic-toxicological testing - Part 1: Decomposition apparatus and determination of test temperature
ES-UNE
- UNE-EN 2923:2019 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification: 600 MPa (at ambient temperature) / 425 °C (Endorsed by Asociación Española de Normalización in May of 2019.)
YU-JUS
- JUS Z.C8.030-1986 Determination of fjammability of plastics. Determination ofthe temperature of evolution of flammable gases (decompositin temperature)
CH-SNV
- VSM 15162-1969 Taper keys with or without gib head and their corresponding keyways (Dimensions in millimetres)
- SN ISO 105/E03:1984 Plastics and ebonite-Determination of temperature of deflection under load
U.S. Military Regulations and Norms
- ARMY MIL-I-3848 A-1963 INDICATOR, PROPELLANT TEMPERATURE, M13, M15 AND M33 (LESS PROPELLANT)
- ARMY MIL-I-3848 A NOTICE 1-1997 INDICATOR, PROPELLANT TEMPERATURE, M13, M15 AND M33 (LESS PROPELLANT)
Association Francaise de Normalisation
- NF L24-526*NF EN 2923:2019 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification : 600 MPa (at ambient temperature)/425 oC
- NF L24-527*NF EN 2924:2019 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated, left hand thread - Classification : 600 MPa (at ambient temperature)/425 oC
- NF ISO 23381:2020 Determination of the desolubilization (crystallization) temperature of liquid fertilizers
Lithuanian Standards Office
- LST EN 4069-2001 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, passivated - Classification: 600 MPa (at ambient temperature)/650°C
CEN - European Committee for Standardization
- EN 2923:2019 "Aerospace series - Nuts@ hexagon@ plain@ reduced height@ reduced across flats@ in heat resisting steel@ silver plated - Classification: 600 MPa (at ambient temperature) / 425 °C,"
- EN 2924:2019 "Aerospace series - Nuts@ hexagon@ plain@ reduced height@ reduced across flats@ in heat resisting steel@ silver plated@ left hand thread - Classification: 600 MPa (at ambient temperature) / 425 °C,"
ASD-STAN - Aerospace and Defence Industries Association of Europe - Standardization
- PREN 4069-1994 Aerospace Series Nuts@ Hexagon@ Plain@ Reduced Height@ Reduced Across Flats@ in Heat Resisting Steel@ Passivated Classification: 600 MPa (at Ambient Temperature) / 650 Degrees C (Edition 1)
- PREN 2923-1992 Aerospace Series Nuts@ Hexagon@ Plain@ Reduced Height@ Reduced Across Flats@ in Heat Resisting Steel@ Silver Plated Classification : 600 MPa (at Ambient Temperature) / 425 Degrees C (Edition P 1)
- PREN 3742-1992 Aerospace Series Nuts@ Hexagonal@ Slotted/ Castellated@ Reduced Height@ Reduced Across Flats@ in Heat Resisting Steel@ Passivated Classification : 600 MPa (at Ambient Temperature)/650 Degrees C (Edition P1)
- PREN 2923-1996 Aerospace Series Nuts@ Hexagon@ Plain@ Reduced Height@ Reduced Across Flats@ in Heat Resisting Steel@ Silver Plated Classification : 600 MPa (at Ambient Temperature) / 425 Degrees C (Edition P 2)
- PREN 3742-2010 Aerospace series Nuts@ hexagonal@ slotted/castellated@ reduced height@ reduced across flats@ in heat resisting steel@ passivated Classification : 600 MPa (at ambient temperature) / 650 °C (Edition P2)
- PREN 2922-2010 Aerospace series Nuts@ hexagon@ plain@ reduced height@ reduced across flats@ in heat resisting steel@ passivated@ left hand thread Classification : 600 MPa (at ambient temperature)/ 650° C (Edition P3)
- PREN 2924-1992 Aerospace Series Nuts@ Hexagon@ Plain@ Reduced Height@ Reduced Across Flats@ in Heat Resisting Steel@ Silver Plated@ Left Hand Thread Classification : 600 MPa (at Ambient Temperature) / 425 Degrees C (Edition P 1)
British Standards Institution (BSI)
- BS EN 2923:2019 Aerospace series. Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated. Classification: 600 MPa (at ambient temperature) / 425 °C
Danish Standards Foundation
- DS/EN 4069:1996 Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, passivated - Classification: 600 MPa (at ambient temperature)/650 °C
American Industrial Hygiene Association (AIHA)
- ASSE 1062-1997 Temperature Actuated,Flow Reduction Valves for Individual Fixture Fittings
International Organization for Standardization (ISO)
- ISO 871:1980 Plastics; Determination of temperature of evolution of flammable gases (decomposition temperature) from a small sample of pulverized material
American Society for Testing and Materials (ASTM)
- ASTM D2879-83 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-86 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-18 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-23 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-97(2007) Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D287-12a Standard Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method)
- ASTM D2879-92e1 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-97 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D287-12 Standard Test Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method)
- ASTM D2879-97(2002)e1 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-96 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
- ASTM D2879-10 Standard Test Method for Vapor Pressure-Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope
Aerospace, Security and Defence Industries Association of Europe (ASD)
- ASD-STAN PREN 3742-2010 Aerospace series Nuts, hexagonal, slotted/castellated, reduced height, reduced across flats, in heat resisting steel, passivated Classification : 600 MPa (at ambient temperature) / 650 癈 Edition P2
General Motors Corporation (GM)
- GM 9986114-1995 Grease, Polyurea, PTFE, Multi-Temperature, NLGI 2
Indonesia Standards
- SNI 7644-2010 Spatial database oceanographic temperature, salinity, dissolved oxygen, pH, turbidity, and brightness
CZ-CSN
- CSN 25 7806-1980 Multi-flow turbine water meters; up-to 95 °C
- CSN 25 7805-1980 Multi-flow turbině water meters; up-to 30 °C
United States Navy
- NAVY MIL-DTL-19772 B-1996 VALVES, TEMPERATURE REGULATING, AUTOMATIC, NAVAL SHIPBOARD
Defense Logistics Agency
- DLA MS28009 REV B VALID NOTICE 3-2005 INDICATOR - TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, -70 TO +150 C, 2-INCH SIZE
- DLA MS28009 REV B-1963 INDICATOR - TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, -70 TO +150 C, 2-INCH SIZE
- DLA MS28009 REV B NOTICE 2-1999 INDICATOR - TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, -70 TO +150 C, 2-INCH SIZE
- DLA MIL-DTL-6669 D-2011 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE, MULTI-FUNCTION, -70 癈 TO +150 癈
- DLA MIL-I-6669 C VALID NOTICE 3-2005 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE, MULTI-FUNCTION, -70 DEG. TO PLUS 150 DEG. C
- DLA MIL-I-6669 C-1972 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE, MULTI-FUNCTION, -70 DEG. TO PLUS 150 DEG. C
- DLA MIL-I-6669 C NOTICE 2-1999 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE, MULTI-FUNCTION, -70 DEG. TO PLUS 150 DEG. C
- DLA MIL-I-6669 C (3)-1982 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE, MULTI-FUNCTION, -70 DEG. TO PLUS 150 DEG. C
Natural Gas Processor's Association (NGPA)
- GPA TP-8-1982 Solubility of Carbon Dioxide in Propylene Carbonate at Elevated Pressures & Higher Than Ambient Temperatures
American Association
- ASSE 1062-2006 Performance Requirements for Temperature Actuated, Flow Reduction (TAFR) Valves for Individual Supply Fittings
U.S. Air Force
- AIR FORCE MIL-I-6533 B (3)-1983 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, TYPE G-10
- AIR FORCE MIL-I-6533 B NOTICE 2-1998 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, TYPE G-10
- AIR FORCE MIL-I-6533 B-1970 INDICATOR, TEMPERATURE, ELECTRICAL RESISTANCE MULTI-FUNCTION, TYPE G-10
PL-PKN
- PN C04545 ArkusZ07-1972 Water and waste water Testt for dissolved oxygen Determination of dissolyed oxygen by Winkler method-difterence modification Rang?: 0,5 mg/l or mor?