Gas phase detection detection

Gas phase detection detection, Total:202 items.

The international standard classification for "Gas phase detection detection" includes: Non-destructive testing , Testing (Vocabularies) , Other standards related to optics and optical measurements , Welded joints , Cosmetics. Toiletries , Non-destructive testing of metals , Biology. Botany. Zoology , Product and company certification. Conformity assessment , Medical Sciences and health care facilities in general .

The Chinese standard classification for "Gas phase detection detection" includes: Basic standards and general methods , chromatograph , X ray, magnetic powder, fluorescent light and other defectoscope , Welding and cutting , Casting , Basic Subject in general , Environmental monitoring instrument and its complete equipment , Hydrogeological survey , Medical science .

General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China

GB/T 31363-2015 Non-destructive testing―Thermal neutron radiographic testing―General principles and basic rules
GB/T 32206-2015 Standard practice for testing electrolytic conductivity detectors usedin gas chrometography
GB 20077667-T-604 Test method of thermal conductivity detector for gas chromatography
GB/T 32190-2015 Standard practice for using flame photometric detectors in gas chromatography
GB/T 41114-2021 Non-destructive testing―Ultrasonic testing―Specification for a calibration block for phased array testing(PAUT)
GB/T 31362-2015 Non-destructive testing―Thermal neutron radiographic testing―Determination of beam L/D ratio
GB/T 32205-2015 Standard practice for testing thermal conductivity detectors used in gas chromatography
GB/T 40734-2021 Non-destructive testing of welds—Phased array ultrasonic testing(PAUT)—Acceptance levels
GB/T 43480-2023 Non-destructive testing—Guided wave testing of ultrasonic phased array cylindrical imaging
GB/T 12604.2-2005 Non-destructive testing - Terminology - Terms used in radiographic testing
GB/T 34637-2017 Non-destructive testing - Test methods for bubble leak detection
GB/T 17455-2008 Non-destructive testing - Metallographic replica techniques of surface examination
GB/T 26642-2011 Non-destructive testing - Test method for computed radiography of metallic materials
GB/T 29302-2012 Non-destructive Testing Instruments - Characterization and Verification of Phased Array Ultrasonic Examination Systems
GB/T 32207-2015 Standard practice for use of electron-capture detectors in gas chromatography
GB/T 40335-2021 Non-destructive testing—Leak testing—Tracer gas method
GB/T 40845-2021 Determination of azelaic acid in cosmetics—Gas chromatography method
GB/T 5677-2018 Castings—Radiographic testing
GB/T 23910-2009 Non-destructive testing—Metal intensifying screens for radiographic testing
GB/T 19495.9-2017 Detection of genetically modified organisms and derived products―Liquid bead array detection for plant products
GB/T 16544-2008 Non-destructive testing - Practice for gamma-ray radiographic testing by panoramic exposure
GB/T 43480-2023(英文版) Non-destructive testing Phased array ultrasonic cylindrical imaging guided wave testing
GB/T 32563-2016 Non-destructive testing―Ultrasonic testing―Test method for phased-array ultrasonic testing
GB/T 34641-2017 Non-destructive testing - Test method for determining image quality in direct thermal neutron radiographic examination

Professional Standard - Civil Aviation

MH/T 3009-2012 Nondestructive testing for aircraft.Radiographic testing

Professional Standard - Machinery

JB/T 9361-1999 Test method for flame ionization detector of gas chromatography
JB/T 9360-1999 Test method for thermal conductivity detector of gas chromatography
JB/T 7902-2006 Non-destructive testing-Image quality indicators(wire type) for radiographic testing
JB/T 10555-2013 Nondestructive Testing - Ultrasonic Testing of Air Valves
JB/T 5075-2004 Non-destructive testing -- Metal intensifying screens for radiographic testing
JB/T 11779-2014 Non-Destructive Testing Instrument - Specifications for Phased Array Ultrasonic Testing Instruments
JB/T 10555-2006 Nondestructive testing-Ultrasonic testing of aivs

Military Standard of the People's Republic of China-General Armament Department

GJB 9787-2020 Specification for gas chromatography-mass spectrometry poison detectors
GJB 1187A-2019 Radiographic testing

Group Standards of the People's Republic of China

T/CRHA 060-2024 Detecting organic acids in urine—Gas chromatography-mass spectrometry method
T/GZTPA 0010-2021 Gas Chromatography Hydrogen Flame Ionization Method for Detection of Soluble Sugar in Guizhou Tea
T/CASEI 044-2024 Testing and evaluation method for welded joints of polyethylene gas pipeline—Phased array ultrasonic testing method
T/NXCL 026-2023 Method for determination of beryllium bronze β phase
T/CCBD 9-2020 Brand evaluation —Testing organizations of indoor air quality and related product
T/QGCML 3963-2024 Gas detector layout line automatic detection system
T/CAS 886-2024 Technical specifications for performance verification of transfusion compatibility testing instrument

Jilin Provincial Standard of the People's Republic of China

DB22/T 243-2019 Vibrio cholerae Detection Gas Chromatography-Mass Spectrometry

National Metrological Verification Regulations of the People's Republic of China

JJG 1022-2016 Verification Regulation of Formaldehyde Gas Detection Instrument
JJG 1105-2015 Ammonia Gas Detectors
JJG 1022-2007 Verification Regulation of Formaldehyde Gas Analyzer

Professional Standard - Geology

DZ/T 0064.74-1993 Groundwater quality test methods - the determination of gas with gas chromatography

Professional Standard - Commodity Inspection

SN/T 0596-2012 Determination of sethoxydim residue in cereals and oilbean for exports. GC/MS

Professional Standard - Coal

MT 273-1994 Detector Tube for Ammonia Gas
MT/T 273-1994 Ammonia gas detection tube
MT 275-1994 Detector Tube for Oxygen
MT 276-1994 Detector Tube for Hydrogen
MT/T 275-1994 Oxygen detection tube
MT/T 276-1994 Hydrogen detection tube

Shandong Provincial Standard of the People's Republic of China

DB37/T 4078-2020 Continuous monitoring of volatile organic compounds in ambient air by gas chromatography-hydrogen flame ionization detector/mass spectrometry detector

Professional Standard - Certification and Accreditation

RB/T 042-2020 Competence assessment of management and technical for inspection body and laboratory—Requirements for electrical inspection and testing

Hebei Provincial Standard of the People's Republic of China

DB13/T 2518-2017 Specifications for inspection and testing of combustible gas and toxic gas detection and alarm systems in industrial enterprises

Professional Standard - Energy

NB/T 47013.15-2021 Nondestructive testing of pressure equipments - Part 15: Phased-array ultrasonic testing

未注明发布机构

DVS 2916-4:2021-04 Metallographic inspection of metal-filled welded joints

Professional Standard - Hygiene

WS/T 794-2022 The technical standard of transfusion compatibility test

Magyar Szabványügyi Testület

MSZ 8888/10.lap-1963 Climate related detection, salt spray related detection
MSZ 8888/11.lap-1967 Climate-related detection. Dust detection
MSZ 8888/16.lap-1963 Climate-related detection. Sealing test
MSZ 8888/12.lap-1963 Climate-related testing of components. Pressure detection
MI 8887/12-1971 Environmental testing planning and climate and mechanics related testing
MSZ 8889/1.lap-1963 Equipment and instruments for climate-related testing. Cold detection
MSZ 8889/2.lap-1963 Equipment and instruments for climate-related testing. Dry heat detection
MSZ 8888/9.lap-1962 Equipment and instruments for climate-related testing. Mildew detection
MSZ 8889/4.lap-1963 Equipment and instruments for climate-related testing. Moisture and heat detection
MSZ 8888/32-1981 environmental test. Cleaning agent related testing
MSZ 6060-3.lap-1959 Air testing. Mining air testing
MSZ 5650/2-1971 Natural gas detection. Thickness detection
MSZ 13555/13-1970 Fuse detection method. Detection of mutual resistance
MSZ 07 UT 6-1972 Soil filling solidity testing. Photophotographic testing
MSZ 21862/25-1983 Detection of gaseous pollutants in the workplace, gas chromatography testing of chlorinated hydrocarbons
MSZ 10985/2-1979 Urban natural gas testing. Combustion detection
MSZ 8888/33-1984 environmental test. Cold/low pressure detection
MSZ 8888/22-1970 environmental test. Atmospheric space effect detection
MSZ 8888/4.lap-1963 Climate detection. Accelerate moisture and heat detection
MI 14026/4-1971 Rubber belt detection, humidity detection, taste taking, separation hardness and water vapor detection
MSZ 21456/5-1986 Air gas pollution detection. Sulfur dioxide content detection
MSZ 8888/30-1979 Environmentally related product testing. Concentrated powder effect testing
MSZ 6060-7.lap-1957 Industrial and mining air testing. Mining gas quality testing
MSZ 9640/33-1979 Paint coating and coating system inspection. Coating compatibility testing
MSZ 21456/31-1983 Air gas pollution detection. Nitrogen hydroxide detection automatic analysis
MSZ 21853/8-1977 Air pollutant content detection. Magnesium oxide content detection
MSZ 6060-5.lap-1957 Industrial and mining air testing. Definition of aniline gas content detection

Association Francaise de Normalisation

NF A09-018*NF ISO 19675:2017 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT)
NF A09-018*NF EN ISO 19675:2024 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT)
NF EN ISO 19675:2024 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT)
NF ISO 23646:2022 Soil quality - Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron capture detection (GC-ECD)
NF EN ISO 20485:2018 Essais non destructifs - Contrôle d'étanchéité - Méthode par gaz traceur
NF A09-492*NF EN ISO 20485:2018 Non-destructive testing - Leak testing - Tracer gas method
NF EN 12679:2018 Non-destructive testing - Radiographic control - Determination of the size of industrial gamma radiography sources
NF ISO 19675:2017 Non-destructive testing - Ultrasonic testing - Calibration block specifications for multi-element technique
NF A09-232*NF EN 12679:2018 Non-destructive testing - Radiographic testing - Determination of the size of industrial radiographic gamma sources
NF A89-513*NF EN ISO 19285:2017 Non-destructive testing of welds - Phased array ultrasonic testing (PAUT) - Acceptance levels

Danish Standards Foundation

DANSK DS/ISO 19675:2024 Non-destructive testing – Ultrasonic testing – Specification for a calibration block for phased array testing (PAUT)
DANSK DS/ISO 23646:2022 Soil quality – Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
DANSK DS/EN ISO 19675:2024 Non-destructive testing – Ultrasonic testing – Specification for a calibration block for phased array testing (PAUT) (ISO 19675:2017)
DANSK DS/ISO 13876:2013 Soil quality - Determination of polychlorinated biphenyls (PCB) by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
DS/EN 13185/A1:2004 Non-destructive testing - Leak testing - Tracer gas method
DS/EN 1593/A1:2004 Non-destructive testing - Leak testing - Bubble emission techniques
DS/EN 1593:2002 Non-destructive testing - Leak testing - Bubble emission techniques
DANSK DS/EN 1593:2001 Non-destructive testing - Leak testing - Bubble emission techniques
DANSK DS/EN ISO 17495:2003 Water quality - Determination of selected nitrophenols - Method by solid-phase extraction and gas chromatography with mass spectrometric detection
DS/EN 16018:2012 Non-destructive testing - Terminology - Terms used in ultrasonic testing with phased arrays

British Standards Institution (BSI)

BS EN ISO 19675:2024 Non-destructive testing. Ultrasonic testing. Specification for a calibration block for phased array testing (PAUT)
BS 5343-1:1986 Gas detector tubes-Specification for short term gas detector tubes
BS ISO 23646:2022 Soil quality. Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
BS EN 1435:1997(2004) Non - destructive testing of welds — Radiographic testing of welded joints
12/30231385 DC BS ISO 13876. Soil quality. Determination of polychlorinated biphenyls (PCB) by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
20/30415503 DC BS ISO 23646. Soil quality. Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
BS EN 1593:1999(2008) Non - destructive testing — Leak testing — Bubble emission techniques
BS EN ISO 17495:2003(2008) Water quality — Determination of selectednitrophenols — Method by solid - phase extraction and gas chromatography with mass spectrometric detection
BS 5475-2:1977 Methods for detection of foreign fats in dairy products-Detection of vegetable fat by gas-liquid chromatography of sterols (reference method)
BS 5343-2:1991 Gas detector tubes - Specification for long term gas detector tubes
BS EN ISO 10893-6:2019 Non-destructive testing of steel tubes. Radiographic testing of the weld seam of welded steel tubes for the detection of imperfections
BS ISO 32679:2024 Non-destructive testing. Radiographic testing. Determination of the size of industrial radiographic gamma sources
BS EN ISO 10893-7:2019 Non-destructive testing of steel tubes. Digital radiographic testing of the weld seam of welded steel tubes for the detection of imperfections

International Organization for Standardization (ISO)

ISO 4773:2023 Non-destructive testing — Ultrasonic guided-wave testing using the phased-array technique
ISO 19675:2017 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT)
ISO/DIS 32679:2023 Non-destructive testing — Radiographic testing — Determination of the size of industrial radiographic gamma sources
ISO/CD 32679:2011 Non-destructive testing — Radiographic testing — Determination of the size of industrial radiographic gamma sources
ISO/FDIS 32679:2024 Non-destructive testing — Radiographic testing — Determination of the size of industrial radiographic gamma sources
ISO 20485:2017 Non-destructive testing - Leak testing - Tracer gas method
ISO 23646:2022 Soil quality — Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
ISO/DIS 4773 Non-destructive testing — Ultrasonic guided wave testing using the phased array technique
ISO 4773:2011 Non-destructive testing — Ultrasonic guided-wave testing using the phased-array technique
ISO 17495 Water quality - Determination of selected nitrophenols - Method by solid-phase extraction and gas chromatography with mass spectrometric detection
ISO/FDIS 4773 Non-destructive testing — Ultrasonic guided wave testing using the phased array technique

German Institute for Standardization

DIN EN ISO 19675:2024 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT) (ISO 19675:2017)
DIN EN ISO 19675:2024-10 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT) (ISO 19675:2017)
DIN EN ISO 19285 E:2016-08 Nondestructive testing of welds Phased array ultrasonic testing (draft)
DIN EN ISO 19675 E:2024 Draft Document - Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT) (ISO 19675:2017); German and English version prEN ISO 19675:2024
DIN EN ISO 20485:2018-05 Non-destructive testing - Leak testing - Tracer gas method (ISO 20485:2017); German version EN ISO 20485:2018
DIN ISO 23646:2023-09 Soil quality - Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD) (ISO 23646:2022)
DIN ISO 23646:2023-03 Soil quality - Determination of organochlorine pesticides by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD) (ISO 23646:2022); Text in German and English / Note: Date of issue 202...
DIN EN 1593:1999-11 Non-destructive testing - Leak testing - Bubble emission techniques; German version EN 1593:1999
DIN 54191:2017-10 Non-destructive testing - Thermographic testing of electric installations
DIN 54191:2017 Non-destructive testing - Thermographic testing of electric installations
DIN 54191:2009-03 Non-destructive testing - Thermographic testing of electric installations
DIN EN ISO 17495:2003-09 Water quality - Determination of selected nitrophenols - Method by solid phase extraction and gas chromatography with mass spectrometric detection (ISO 17495:2001); German version EN ISO 17495:2003
DIN EN ISO 20485 E:2016-10 Non-destructive testing leak detection tracer gas method (draft)
DIN EN ISO 13588:2019-07 Non-destructive testing of welds - Ultrasonic testing - Use of automated phased array technology (ISO 13588:2019); German version EN ISO 13588:2019

Spanish Association for Standardization (UNE)

UNE-EN 16167:2018/AC:2019 Determination of polychlorinated biphenyls (PCBs) in soil, treated biological waste and sludge by gas chromatography-mass spectrometry detection (GC-MS) and gas chromatography-electron capture detection (GC-ECD)
UNE-EN 13185/A1:2004 Non-destructive testing - Leak testing - Tracer gas method
UNE-EN ISO 20485:2018 Non-destructive testing - Leak testing - Tracer gas method (ISO 20485:2017)
UNE-EN 1435:1998 NON-DESTRUCTIVE EXAMINATION OF WELDS. RADIOGRAPHIC EXAMINATION OF WELDED JOINTS.
AENOR UNE 34865:1983 Milk fat. Detection of vegetable fat by sterol gas chromatography.
UNE-EN 1593/A1:2004 Non-destructive testing - Leak testing - Bubble emission techniques
UNE-EN 16018:2012 Non-destructive testing - Terminology - Terms used in ultrasonic testing with phased arrays
UNE-EN ISO 19285:2018 Non-destructive testing of welds - Phased array ultrasonic testing (PAUT) - Acceptance levels (ISO 19285:2017)
UNE-EN ISO 13588:2020 Non-destructive testing of welds - Ultrasonic testing - Use of automated phased array technology (ISO 13588:2019)

Standards Norway

NS-EN ISO 19675:2024 Non-destructive testing - Ultrasonic testing - Specification for a calibration block for phased array testing (PAUT) (ISO 19675:2017)
NS-EN 12679:2018 Non-destructive testing — Radiographic testing — Determination of the size of industrial radiographic gamma sources
NS-EN 13185:2001 Non-destructive testing — Leak testing — Tracer gas method
NS-EN 1593:1999 Non-destructive testing — Leak testing — Bubble emission techniques
NS-EN 16018:2011 Non-destructive testing — Terminology — Terms used in ultrasonic testing with phased arrays

BR-ABNT

ABNT MB-114-1951 Single-phase electronic measuring instrument detection

The Directorate General of Specifications and Metrology (DGSM)

OS GSO ISO 13876:2015 Soil quality -- Determination of polychlorinated biphenyls (PCB) by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
OS GSO ISO 17495:2013 Water quality -- Determination of selected nitrophenols -- Method by solid-phase extraction and gas chromatography with mass spectrometric detection

YU-JUS

JUS C.A7.091-1985 Non-destructive testing. Metallographic replica technigues ofsurface examination

Kingdom of Bahrain Testing and Metrology Directorate

BH GSO ISO 13876:2017 Soil quality -- Determination of polychlorinated biphenyls (PCB) by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
BH GSO ISO 19675:2022 Non-destructive testing — Ultrasonic testing — Specification for a calibration block for phased array testing (PAUT)
BH GSO ISO 17495:2016 Water quality -- Determination of selected nitrophenols -- Method by solid-phase extraction and gas chromatography with mass spectrometric detection
BH GSO ISO 3057:2016 Non-destructive testing -- Metallographic replica techniques of surface examination

Japanese Industrial Standards Committee (JISC)

JIS Z 2329:2019 Non-destructive testing -- Methods for bubble leak testing

Gosstandart of Russia

GOST 33490-2015 Milk and milk products. Detection of vegetable fat by gas chromatography with mass spectrometric detection

Ente Nazionale Italiano di Unificazione

UNI EN ISO 20485:2018 Non-destructive testing - Leak testing - Tracer gas method
UNI EN 1593:2001 Non-destructive testing - Leak testing - Bubble emission techniques
UNI EN 12393-3:1999 Non-fatty foods - Multiresidue methods for the gas chromatographic determination of pesticide residues - Determination and confirmatory tests
UNI EN ISO 19285:2017 Non-destructive testing of welds - Phased array ultrasonic testing (PAUT) - Acceptance levels

CEN - European Committee for Standardization

EN ISO 20485:2018 Non-destructive testing - Leak testing - Tracer gas method

Lithuanian Standards Office

LST EN 13185-2002/A1-2004 Non-destructive testing - Leak testing - Tracer gas method
LST EN 13185-2002 Non-destructive testing - Leak testing - Tracer gas method
LST EN 1593-2001/A1-2004 Non-destructive testing - Leak testing - Bubble emission techniques
LST EN 1435-1998/A2-2004 Non-destructive testing of welds - Radiographic testing of welded joints
LST EN 1435-1998 Non-destructive examination of welds - Radiographic examination of welded joints
LST EN 1435-1998/A1-2002 Non-destructive testing of welds - Radiographic testing of welded joints
LST EN 1593-2001 Non-destructive testing - Leak testing - Bubble emission techniques
LST EN 16018-2012 Non-destructive testing - Terminology - Terms used in ultrasonic testing with phased arrays

GCC Standardization Organization

GSO ISO 13876:2015 Soil quality -- Determination of polychlorinated biphenyls (PCB) by gas chromatography with mass selective detection (GC-MS) and gas chromatography with electron-capture detection (GC-ECD)
GSO ISO 17495:2013 Water quality -- Determination of selected nitrophenols -- Method by solid-phase extraction and gas chromatography with mass spectrometric detection
GSO ISO 19675:2021 Non-destructive testing — Ultrasonic testing — Specification for a calibration block for phased array testing (PAUT)
GSO ISO 19285:2021 Non-destructive testing of welds — Phased array ultrasonic testing (PAUT) — Acceptance levels

Swedish Institute for Standards

SS-EN 13185:2001 Non destructive testing - Leak testing - Tracer gas method
SS-EN 1593:1999 Non-destructive testing - Leak testing - Bubble emission techniques

Acoustical Society of America (ASA)

ASA S1.24 TR-2002(R2007) Bubble Detection and Cavitation Monitoring

Korean Agency for Technology and Standards (KATS)

KS B ISO 19285-2018(2023) Non-destructive testing of welds — Phased array ultrasonic testing(PAUT) — Acceptance levels
KS I ISO 17495-2007(2017) Water quality－Determination of selected nitrophenols－Method by solidphase extraction and gas chromatography with mass spectrometric detection
KS B ISO 12721-2023 Non-destructive testing — Thermal neutron radiographic testing — Determination of beam L/D ratio
KS B ISO 10893-6-2023 Non-destructive testing of steel tubes — Part 6: Radiographic testing of the weld seam of welded steel tubes for the detection of imperfections
KS B ISO 19285-2023 Non-destructive testing of welds — Phased array ultrasonic testing(PAUT) — Acceptance levels
KS I ISO 17495-2023 Water quality — Determination of selected nitrophenols — Method by solid-phase extraction and gas chromatography with mass spectrometric detection
KS B ISO 3057-2018 Non-destructive testing — Metallographic replica techniques of surface examination
KS B ISO 3057-2023 Non-destructive testing — Metallographic replica techniques of surface examination
KS B ISO 3057:2018 Non-destructive testing — Metallographic replica techniques of surface examination
KS I ISO 18287-2018(2024) Soil quality — Determination of polycyclic aromatic hydrocarbons(PAH) — Gas chromatographic method with mass spectrometric detection(GC-MS)
KS B ISO 11537-2008(2013) Non-destructive testing－Thermal neutron radiographic testing－General principles and basic rules
KS D 0227-2023 Radiographic testing for steel castings

Bureau of Indian Standards

IS/ISO 3057-1998 Non-destructive Testing —— Metallographic Replica Techniques of Surface Examination

American Society for Testing and Materials (ASTM)

ASTM D7493-08 Standard Test Method for Online Measurement of Sulfur Compounds in Natural Gas and Gaseous Fuels by Gas Chromatograph and Electrochemical Detection