	US 11,796,525 B2
	Instrument and method for simultaneously testing molecular weight distribution and organic nitrogen level of water sample
Lei Li, Shanghai (CN); Wenjun Zhang, Shanghai (CN); and Shichong Wang, Shanghai (CN)
Assigned to TONGJI UNIVERSITY, Shanghai (CN)
Appl. No. 17/56,425
Filed by TONGJI UNIVERSITY, Shanghai (CN)
PCT Filed Aug. 29, 2018, PCT No. PCT/CN2018/102945 § 371(c)(1), (2) Date Nov. 18, 2020, PCT Pub. No. WO2019/218530, PCT Pub. Date Nov. 21, 2019.
Claims priority of application No. 201810480696.0 (CN), filed on May 18, 2018.
Prior Publication US 2021/0208116 A1, Jul. 8, 2021
Int. Cl. G01N 33/18 (2006.01); G01N 21/78 (2006.01); G01N 30/04 (2006.01); G01N 30/64 (2006.01); G01N 30/88 (2006.01); G01N 30/14 (2006.01)

CPC G01N 33/182 (2013.01) [G01N 21/78 (2013.01); G01N 30/14 (2013.01); G01N 30/64 (2013.01); G01N 30/88 (2013.01); G01N 33/1846 (2013.01); G01N 2030/645 (2013.01); G01N 2030/884 (2013.01)]

10 Claims

1. An instrument for simultaneously testing a molecular weight distribution and an organic nitrogen of water samples, comprising a tail-end injection valve, a chromatographic column, a pressure relief valve, an acid-adding injection valve, an oxygen-adding injection valve, an helical tube for an acid-oxygen reaction, a carbon dioxide (CO₂) remover, a ultraviolet digester, a second gas-water separation membrane, a buffer solution injection valve, a helical tube for a buffer solution reaction, a cadmium column, a chromogenic agent injection valve, a helical tube for a chromogenic agent reaction and a ultraviolet detector, sequentially connected via a pipeline, the tail-end injection valve is configured to receive a fluid phase and a sample, the second gas-water separation membrane is connected to an electrical conductivity-based CO₂detector, the ultraviolet detector and the electrical conductivity-based CO₂detector are both connected to a data processing computer.