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Spectrophotometric determination of nitrogen content

Spectrophotometric determination of nitrogen content, Total:173 items.

In the international standard classification, Spectrophotometric determination of nitrogen content involves: Sugar. Sugar products. Starch, Air quality, Analytical chemistry, Ferrous metals, Tea. Coffee. Cocoa, Inorganic chemicals, Fertilizers, Non-metalliferous minerals, Ferroalloys, Conducting materials, Metalliferous minerals, Non-ferrous metals, Spices and condiments. Food additives, Milk and milk products, Farming and forestry, Water quality, Vocabularies, Nuclear energy engineering, Iron and steel products, TEXTILE AND LEATHER TECHNOLOGY, Pharmaceutics, Animal feeding stuffs, Testing of metals, Soil quality. Pedology.

Korean Agency for Technology and Standards (KATS), Spectrophotometric determination of nitrogen content

KS H ISO 5378-2008(2018) Starches and derived products－Determination of nitrogen content by the Kjeldahl method－Spectrophotometric method
KS H ISO 5378:2008 Starches and derived products－Determination of nitrogen content by the Kjeldahl method－Spectrophotometric method
KS D ISO 4945:2002 Steel－Determination of nitrogen content－Spectrophotometric method
KS D ISO 4945-2002(2017) Steel－Determination of nitrogen content－Spectrophotometric method
KS D ISO 1053-2002(2007) Zinc－Determination of copper content?Spectrophotometric method
KS D ISO 17058:2005 Steel and iron－Determination of arsenic content－ Spectrophotometric method
KS D ISO 9441:2002 Steel－Determination of niobium content－PAR spectrophotometric method
KS D ISO 17058:2020 Steel and iron — Determination of arsenic content —Spectrophotometric method
KS E ISO 8556:2001 Aluminium ores－Determination of phosphorus content－Molybdenum blue spectrophotometric method
KS D ISO 10153:2007 Steel－Determination of boron content－Curcumin spectrophotometric method
KS D ISO 4942:2002 Steel and iron－Determination of vanadium content－N-BPHA spectrophotometric method
KS D ISO 629:2008 Steel and cast iron－Determination of manganese content－Spectrophotometric method
KS E ISO 9683-1:2010 Iron ores－Determination of vanadium－Part 1：BPHA spectrophotometric method
KS D ISO 10153-2007(2022) Steel－Determination of boron content－Curcumin spectrophotometric method
KS E ISO 9208-2001(2016) Aluminium ores ― Determination of vanadium content ― BPHA spectrophotometric method
KS D ISO 11652:2002 Steel and iron－Determination of cobalt content－Flame atomic absorption spectrometric method

Indonesia Standards, Spectrophotometric determination of nitrogen content

SNI 19-7119.2-2005 Ambient atmospheres - Part 2: Test methods of nitrogen dioxide (NO2) content by Griess Saltzman using spectrophotometers

Danish Standards Foundation, Spectrophotometric determination of nitrogen content

DS/EN ISO 5378:1995 Starches and derived products - Determination of nitrogen content by the Kjeldahl method - Spectrophometric method
DS/EN ISO 4945:2009 Steel - Determination of nitrogen content - Spectrophotometric method
DS/EN 10179:1989 Chemical analysis of ferrous materials. Determination of nitrogen (trace amount) in steels. Spectrophotometric method

International Organization for Standardization (ISO), Spectrophotometric determination of nitrogen content

ISO 5378:1978 Starches and derived products; Determination of nitrogen content by the Kjeldahl method; Spectrophotometric method
ISO 4945:1977 Steel; Determination of nitrogen content; Spectrophotometric method
ISO 4945:2018 Steel - Determination of nitrogen - Spectrophotometric method
ISO 2991:1974 Nitric acid for industrial use; Determination of ammoniacal nitrogen content; Spectrophotometric method
ISO 2899:1974 Sulphuric acid and oleums for industrial use; Determination of ammoniacal nitrogen content; Spectrophotometric method
ISO 1053:1975 Zinc; Determination of copper content; Spectrophotometric method
ISO 17058:2004 Steel and iron - Determination of arsenic content - Spectrophotometric method
ISO 9441:1988 Steel; determination of niobium content; PAR spectrophotometric method
ISO 4941:1994 Steel and iron - Determination of molybdenum content - Thiocyanate spectrophotometric method
ISO 3886:1977 Iron ores — Determination of manganese content — Spectrophotometric method
ISO 7834:1987 Iron ores; Determination of arsenic content; Molybdenum blue spectrophotometric method
ISO 629:1982 Steel and cast iron; Determination of manganese content; Spectrophotometric method
ISO 9683:1991 Iron ores; determination of vanadium content; BPHA spectrophotometric method
ISO 10153:1991 Steel; determination of boron content; curcumin spectrophotometric method
ISO 6491:1998 Animal feeding stuffs - Determination of phosphorus content - Spectrometric method
ISO 3709:1976 Phosphoric acid for industrial use (including foodstuffs); Determination of oxides of nitrogen content; 3,4- Xylenol spectrophotometric method

Association Francaise de Normalisation, Spectrophotometric determination of nitrogen content

NF V03-608*NF EN ISO 5378:1994 Starches and derived products. Determination of nitrogen content by the kjeldahl method. Spectrophotometric method.
NF T20-286:1982 Nitric acid for industrial use. Determination of ammoniacal nitrogen content. Spectrophotometric method.
NF A06-323:1987 Chemical analysis of steels. Determination of nitrogen content. Molecular absorption spectrophotometric method.
NF A06-555:2010 Steel - Determination of nitrogen content - Spectrophotometric method.
NF A06-555*NF EN ISO 4945:2018 Steel - Determination of nitrogen - Spectrophotometric method
NF T90-139*NF EN ISO 17852:2008 Water quality - Determination of mercury - Method using atomic fluorescence spectrometry
NF A20-430*NF ISO 7834:1988 Iron ores. Determination of arsenic content. Molybdenum blue spectrophotometric method.
NF A08-709-1*NF EN 14937-1:2006 Copper and copper alloys - Determination of antimony content - Part 1 : spectrophotometric method.
NF A20-401:1985 Iron ores. Determination of phosphorus content. Spectrophotometric method.
NF A20-423:1986 Iron ores. Determination of titanium content. Spectrophotometric determination.

Professional Standard - Aviation, Spectrophotometric determination of nitrogen content

HB 5220.38-2008 Methods for chemical analysis of superalloys. Part 38: Determination of cerium content by extraction separation-arsenazo Ⅲ photometric method
HB 5297.17-2001 Chemical Analysis Method of Titanium Alloy AzoarsenicⅢ Spectrophotometric Determination of Zirconium Content
HB 5220.42-1995 Determination of Cerium Content by DBC-Arsenazo Absorption Spectrophotometry Method for Chemical Analysis of Superalloys
HB 5220.43-1995 Determination of Lanthanum Content by DBC-Arsenazo Absorption Spectrophotometry Method for Chemical Analysis of Superalloys
HB 5422.23-1989 Determination of zirconium content by arsenazoⅢ absorptiophotometric method for chemical analysis of copper alloy
HB 5220.42-2008 Methods for chemical analysis of superalloys. Part 42: Determination of cerium content by DBC-arsenazo photometric method
HB 5220.43-2008 Methods for chemical analysis of superalloys. Part 43: Determination of lanthanum content by DBC-arsenazo photometric method
HB 5220.38-1995 Extraction and Separation by Chemical Analysis Method of Superalloy - Determination of Cerium Content by ArsenazoⅢ Absorbance Spectrophotometry
HB 5297.20-2001 Chlorophosphine azo Ⅲ Spectrophotometric Method for Chemical Analysis of Titanium Alloy Determination of Cerium Content
HB 5220.36-1995 Determination of Zirconium Content by Arsenazo Ⅲ Direct Absorption Spectrophotometry Method for Chemical Analysis of Superalloys
HB 5220.48-1995 Superalloy Chemical Analysis Method Water Steam Distillation - Volumetric Method (or Absorptiometry) Determination of Nitrogen Content
HB 5219.19-1998 Determination of Cerium Content by Spectrophotometric Method of Tribromoarsine in Magnesium Alloy

German Institute for Standardization, Spectrophotometric determination of nitrogen content

DIN EN ISO 5378:1994-10 Starches and derived products - Determination of nitrogen content by the Kjeldahl method - Spectrophotometric method (ISO 5378:1978); German version EN ISO 5378:1994
DIN EN ISO 4945:2010 Steel - Determination of nitrogen content - Spectrophotometric method (ISO 4945:1977); German version EN ISO 4945:2009
DIN EN ISO 5378:1994 Starches and derived products - Determination of nitrogen content by the Kjeldahl method - Spectrophotometric method (ISO 5378:1978); German version EN ISO 5378:1994
DIN EN 10179:2023-07 Steels - Determination of nitrogen (trace amounts) - Spectrophotometric method; German and English version prEN 10179:2023 / Note: Date of issue 2023-05-26*Intended as replacement for DIN EN 10179 (1990-04).
DIN EN ISO 4945:2019-03 Steel - Determination of nitrogen - Spectrophotometric method (ISO 4945:2018); German version EN ISO 4945:2018
DIN EN ISO 4945:2019 Steel - Determination of nitrogen - Spectrophotometric method (ISO 4945:2018)

Lithuanian Standards Office , Spectrophotometric determination of nitrogen content

LST EN ISO 5378:2000 Starches and derived products - Determination of nitrogen content by the Kjeldahl method - Spectrophotometric method (ISO 5378:1978)
LST EN ISO 4945:2010 Steel - Determination of nitrogen content - Spectrophotometric method (ISO 4945:1977)

AENOR, Spectrophotometric determination of nitrogen content

UNE-EN ISO 5378:1995 STARCHES AND DERIVED PRODUCTS. DETERMINATION OF NITROGEN CONTENT BY THE KJELDHAL METHOD. SPECTROPHOTOMETRIC METHOD. (ISO 5378:1978).
UNE-EN ISO 4945:2010 Steel - Determination of nitrogen content - Spectrophotometric method (ISO 4945:1977)
UNE 37258:1986 LEAD. DETERMINATION OF ARSENIC CONTENT. SPECTROPHOTOCOLORIMETRY METHOD.
UNE 35026-1:1985 FERROALLIAGES. DETERMINATION OF PHOSPHORUS CONTENT. SPECTROPHOTOMETRIC METHOD

RO-ASRO, Spectrophotometric determination of nitrogen content

SR ISO 6685:1996 Chemical products for industrial use-General method for determination of iron content - 1,10 - Phenanthroline spectrophotometric method
STAS SR 13257-1996 COFFEE Determination of nitrogen content by the Kjeldahi method Spectrophotometric method
STAS SR 9763-13-1996 Spices and condiments. Determination of nitrogen content by the Kjeldahl method. Spectrophotometric method
STAS SR EN 10179-1994 Chemicat analysis of ferrous materials - Determination of nitrogen (trace amounts) in steel - Spectrophotometric method
STAS SR 13145-1993 Cast irons and steels. Determination of tantalum content. Spectrophotometrical method
STAS SR 13362-1996 Sodium chloride. Determination of iron. 1,10 - phenanthroline Photometric Method
STAS SR 11039-5-1996 Silicocalcium. Determination of phosphorus content. Spectrophotometric method
STAS SR 13385-1997 Leather - Determination of hydroxyproline - Spectrophotometrie analysis
STAS SR 13144-1993 Cast irons and steels. Determination of antimony conterit Spectrophotometrical method
SR ISO 4942:1994 Steel and iron. Determination of vanadium content. N-BPHA spectrophotometric method

BE-NBN, Spectrophotometric determination of nitrogen content

NBN-EN ISO 5378:1994 Starches and derived products - Determination of nitrogen content by the Kjeldahl method - Spectrophotometric method (ISO 5378:1978)
NBN T 03-041-1979 Nitric acid for industrial use - Determination of ammoniacal nitrogen content - Spectrophotometric method
NBN P 32-004-1977 Zinc - Determination of copper content -Spectrophotometric method
NBN T 03-024-1979 Sulphuric acid and oleum for industrial use - Determination of ammoniacal nitrogen content - Spectrophotometric method
NBN T 04-304-1983 Urea for indus trial use - Determination of iron content-2,2'-Bipyridyl photometric method
NBN T 03-270-1980 Phosphoric acid for industrial use (including foodstuffs)-Determi-nation of oxides of nitrogen content - 3,4-Xylenol spectrophotometric method

CEN - European Committee for Standardization, Spectrophotometric determination of nitrogen content

EN ISO 4945:2018 Steel - Determination of nitrogen - Spectrophotometric method

British Standards Institution (BSI), Spectrophotometric determination of nitrogen content

BS EN ISO 4945:2010 Steel. Determination of nitrogen content. Spectrophotometric method
BS EN ISO 4945:2009 Steel - Determination of nitrogen content - Spectrophotometric method
23/30472739 DC BS EN 10179. Steels. Determination of nitrogen (trace amounts). Spectrophotometric method
BS ISO 17058:2004 Steel and iron - Determination of arsenic content - Spectrophotometric method
BS EN ISO 4945:2018 Tracked Changes. Steel. Determination of nitrogen. Spectrophotometric method
BS EN 14937-1:2006 Copper and copper alloys - Determination of antimony content - Spectrophotometric method

European Committee for Standardization (CEN), Spectrophotometric determination of nitrogen content

EN ISO 4945:2009 Steel - Determination of nitrogen content - Spectrophotometric method (ISO 4945:1977)
EN 10179:1989 Chemical Analysis of Ferrous Materials - Determination of Nitrogen (Trace Mounts) in Steel Spectrophotometric Method

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China, Spectrophotometric determination of nitrogen content

GB 223.30-1984 Methods for chemical analysis of iron,steel and alloy--The arsenazo 3 photometric method for the determination of zirconium content after separation by p-bromomandelic acid
GB/T 5195.10-2006 Fluorspar. Determination of iron content. 1,10-phenanthroline spectrophotometric method
GB/T 24583.5-2009 Vanadium-Nitrogen alloy.Determination of phosphorus content.The bismuth molybdenum blue spectrophotometry method
GB/T 223.70-2008 Iron,steel and alloy.Determination of iron contents. o-Phenanthroline spectrophotometric method
GB/T 4702.7-2016 Chromium metal.Determination of nitrogen content.Distillation-nessler reagent spectrophotometric method
GB/T 4699.3-2007 Ferrochromium, silicochromium and nitrogen-bearing ferrochromium.Determination of phosphorus content.Molybdobismuthylphosphoric blue speckophotometric method and the molybdenum blue spectrophotometric method
GB/T 17528-1998 Determination of piperine content--Spectrophotometric method
GB/T 13748.9-2005 Chemical analysis methods of magnesium and magnesium alloys.Determination of iron content.Orthopenanthroline spectrophotometric method
GB/T 5686.4-2022 Ferromanganese, ferromanganese-silicon, nitrogen-bearing ferromanganese and manganese metal—Determination of phosphorus content—Molybdenum blue spectrophotometric method and bismuth phosphomolybdate b
GB/T 14849.1-2007 Methods for chemical analysis of silicon metal-Part 1:Determination of iron content-1,10-Phenanthrolion spectrophotometric method
GB/T 8704.7-2009 Ferrovanadium.Determination of phosphorus content.The molybdenum blue photometric method
GB/T 8220.2-1998 Methods for chemical analysis bismuth--Determination of iron content--1,10-Phenanthroline photometric method
GB/T 20931.9-2007 Methods for chemical analysis of lithium Determination of nitrogen content Mercuric potassium iodide spectrophotometric method
GB/T 13748.9-2013 Chemical analysis methods of magnesium and magnesium alloys.Part 9:Determination of iron content.Orthopenanthroline spectrophotometric method
GB/T 7493-1987 Water quality--Determination of nitrogen (nitrite)--Spectrophotometric method
GB/T 32737-2016 Determination of nitrate nitrogen in soil - Ultraviolet spectrophotometry method

YU-JUS, Spectrophotometric determination of nitrogen content

JUS H.B8.287-1983 Fertilizers. Determination of content amid-nitrogen. Spectrophotometric method
JUS H.B8.637-1981 Sulphuric acid for industrial use. Determination of ammoniacal nitrogen content. Spectrophotometric method
JUS H.G8.418-1991 Reagents. Sodium hvdroxide. Determination of arsenic content. Silver diethvldithiocarbamate spectrophotometric method
JUS H.B8.815-1992 Straight ammonium nitrate fertilizers of high nitrogen content - Determination of copper content - Atomic absorption spectrophotometric method
JUS H.G8.130-1984 Reagents. Ammonia solution. Determination of iron content. 1,10—Phenanthrolinespectrophotometric method
JUS B.G8.111-1989 Iron ores. Determination of manganese content. Spectrophotometric nethod
JUS H.F8.232-1986 Gases. Determination of hydrocarbons content. Infrared spectrophotometric method
JUS H.B8.043-1991 Liquid hydrocarbons. Determination of total chloride content. Spectrophotonetric method

TR-TSE, Spectrophotometric determination of nitrogen content

TS 2466-1976 Nitric Acit For Industrial Use Determination of Ammoniacal Nitrogen Content Spectrophotoraetric Method
TS 3651-1981 METHODS FOR THE ANALYSIS OF WATER — DETERMINATION OF IRON CONTENT — 1,10 Phenanthroline Spectrophotometry Method
TS 2918-1978 PHOSPHORIC ACID FOR INDUSTRIAL USE (INCLUDING FOODSTUFFS) — DETERMINATION OF OXIDES OF NITROGEN CONTENT — 3,4 — XYLENOL SPECTROPHOTOMETRY

Professional Standard - Agriculture, Spectrophotometric determination of nitrogen content

NY/T 1116-2006 Fertilizers-Determination of nitrate nitrogen content.UItraviolet spectro-photometric method
NY/T 2332-2013 Determination of total sugars in red ginseng.Spectrophotometry

国家市场监督管理总局、中国国家标准化管理委员会, Spectrophotometric determination of nitrogen content

GB/T 24583.5-2019 Vanadium-nitrogen—Determination of phosphorus content—Bismuth molybdenum blue spectrophotometric method
GB/T 223.37-2020 Iron, steel and alloy—Determination of nitrogen content—Indophenol blue spectrophotometric method after distillation separation

工业和信息化部, Spectrophotometric determination of nitrogen content

YB/T 4582.6-2017 Determination of silicon ferromanganese nitride content sodium periodate spectrophotometry
YB/T 4566.6-2016 Determination of phosphorus content in vanadium iron nitride bismuth phosphorus molybdenum blue spectrophotometry
YB/T 4582.3-2017 Determination of phosphorus content in silicon iron nitride bismuth phosphorus molybdenum blue spectrophotometry
YB/T 4582.2-2017 Determination of ferrochromium content in silicon nitride diphenylcarbazide spectrophotometric method
YB/T 4582.9-2017 Determination of titanium silicon nitride content diantipyrine methane spectrophotometry

CZ-CSN, Spectrophotometric determination of nitrogen content

CSN EN 10 179-1993 Chemical analysis of ferrous metals — Determination of nitrogen (trace amounts) in steels — Spectrophotometric method
CSN ISO 9061:1992 Acid-grade and ceramic-grade fluorspar - Determination of iron content - 1,10-Phenantroline spectrometric method
CSN 65 1025 Cast.10-1989 Sulphuric acid for industrial use. pectrophotometric method for the etermination of total nitrogen xides
CSN ISO 4751:1992 Copper and copper alloys - Determination of tin content - Spectrometric method
CSN ISO 4942:1993 Steel and iron. Determination of the vanadium content. N-BPHA spectrophotometric method

Professional Standard - Ferrous Metallurgy, Spectrophotometric determination of nitrogen content

YB/T 5330-2009 Determination of Ferrovanadium Pentoxide Content O-Phenanthroline Spectrophotometry
YB/T 190.8-2014 Continuous casting powder.The determination of iron content.The o-phenanthroline spectrophotometric method and the flame atomic absorption method
YB/T 505.5-2007 Vanadium and titanium slag Determination of ferric oxide content-Photometric method

PT-IPQ, Spectrophotometric determination of nitrogen content

NP 1841-1985

ES-UNE, Spectrophotometric determination of nitrogen content

UNE-EN ISO 4945:2019 Steel - Determination of nitrogen - Spectrophotometric method (ISO 4945:2018)

KR-KS, Spectrophotometric determination of nitrogen content

KS D ISO 4945-2022 Steel — Determination of nitrogen — Spectrophotometric method
KS D ISO 17058-2020 Steel and iron — Determination of arsenic content —Spectrophotometric method
KS D ISO 629-2008(2023) Steel and cast iron－Determination of manganese content－Spectrophotometric method

Heilongjiang Provincial Standard of the People's Republic of China, Spectrophotometric determination of nitrogen content

DB23/T 2963-2021 Determination of Trace Calcium Content in Natural Flake Graphite by Calcium-Arsenazo Ⅲ Spectrophotometric Method
DB23/T 1382-2010 Spectrophotometric method for determination of urea content in feed

IT-UNI, Spectrophotometric determination of nitrogen content

UNI 7336-1974 Chemical analysis of ferrous materials. Determination of nitrogen in steel. Spectrophotometric method.

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, Spectrophotometric determination of nitrogen content

GB/T 6730.44-2017 Iron ores—Determination of zinc content—1-(2-pyridylazo)-2-naphthol spectrophotometric method
GB/T 5195.6-2017 Fluorspar—Determination of phosphorus content—Photometric method
GB/T 6730.37-2017 Iron ores—Determination of cobalt content—4-[(5-chloro-2-pyridyl)azo]-1,3-diamino-benzene spectrophotometric method

未注明发布机构, Spectrophotometric determination of nitrogen content

BS ISO 17058:2004(2008) Steel and iron — Determination of arsenic content — Spectrophotometric method

VN-TCVN, Spectrophotometric determination of nitrogen content

TCVN 7724-2007 Water quality.Determination of merdury.Method using atomic fluorescence spectrometry
TCVN 1525-2001 Animal feeding stuffs.Determination of Phosphorus content.Spectrometric method

RU-GOST R, Spectrophotometric determination of nitrogen content

GOST 31584-2012 Milk. Spectrophotometric method for determination of total phosphorus content
GOST 31980-2012 Milk. Spectrometric method for determination of total phosphorus content
GOST 30181.5-1994 Mineral fertilizers. Method for determination of mass fraction of amide nitrogen in compound fertilizers (spectrophotocolorimetric method)

NL-NEN, Spectrophotometric determination of nitrogen content

NEN 6520-1981 Water - Spectrophotometric determination of chlorophyll a content
NEN 2848-1986 Fruit juices - Determination of the total pectin content - Spectrophotometric method
NEN 6646-1990 Water - Photometric determination of the content of ammonium nitrogen and of the sum of the contents of ammoniacal and organically bound nitrogen according to Kjeldahl by continuous flow analysis

Professional Standard - Petrochemical Industry, Spectrophotometric determination of nitrogen content

SH/T 0020-1990 Determination of phosphorus content in gasoline (spectrophotometry)

Professional Standard - Water Conservancy, Spectrophotometric determination of nitrogen content

SL 84-1994 Determination of nitrogen (nitrate)(Ultraviolet spectrophtometric method)

Professional Standard - Environmental Protection, Spectrophotometric determination of nitrogen content

HJ 1191-2021 Spectrophotometric method for the determination of water quality azide
HJ 536-2009 Water quality.Determination of ammonia nitrogen.Salicylic acid spectrophotometry

Professional Standard - Non-ferrous Metal, Spectrophotometric determination of nitrogen content

YS/T 535.4-2009 Chemical analysis methods of sodium fluoride.Part 4:Determination of iron content.1,10-phenanthroline spectrophotometric method
YS/T 74.7-1994 Cadmium Chemical Analysis Method 1,10-Phenanthroline Spectrophotometric Determination of Iron Content
YS/T 536.2-2006 Bismuth Chemical Analysis Method 1,10-Phenanthroline Spectrophotometric Determination of Iron Content

Professional Standard - Nuclear Industry, Spectrophotometric determination of nitrogen content

EJ/T 20167-2018 Determination of nitrogen content in reprocessed uranium trioxide powder by distillation-Nessler reagent spectrophotometry

Shandong Provincial Standard of the People's Republic of China, Spectrophotometric determination of nitrogen content

DB37/T 3314-2018 Determination of Alginic Acid Content in Fertilizer by Spectrophotometry
DB37/T 3313-2018 Determination of Chitosan Content in Fertilizer by Spectrophotometry

Yunnan Provincial Standard of the People's Republic of China, Spectrophotometric determination of nitrogen content

DB53/T 729-2015 Determination of germanium content in zinc materials spectrophotometric method

Group Standards of the People's Republic of China, Spectrophotometric determination of nitrogen content

T/NAIA 097-2021 Determination of total phenolic content in Lycium barbarum by spectrophotometric method

Jilin Provincial Standard of the People's Republic of China, Spectrophotometric determination of nitrogen content

DB22/T 2288-2015 Determination of Phospholipid Content in Deer Antler by Spectrophotometry

中华人民共和国环境保护部, Spectrophotometric determination of nitrogen content

GB 7493-1987 Water quality-Determination of nitrogen (nitrite)-Spectrophotometric method