Enhancement of Chemiluminescence Intensity of S2* in Non-premixed Hydrogen Microjet Flame in the Photometric Detector for Sulfur Detection

2021 ◽  
Vol 93 (4) ◽  
pp. 1969-1975
Author(s):  
Lanxiu Ni ◽  
Shenghong Li ◽  
Kun Ding ◽  
Xuhui Geng ◽  
Chunfeng Duan ◽  
...  
Keyword(s):  
Chemiluminescence Intensity ◽  
Photometric Detector

Gas Chromatographic Determination of Ametryn and Its Metabolites in Tropical Root Crops

1984 ◽  
Vol 67 (2) ◽  
pp. 280-284
Author(s):  
Promode C Bardalaye ◽  
Willis B Wheeler
Keyword(s):  
Anhydrous Sodium Sulfate ◽  
Residue Analysis ◽  
Gel Permeation Chromatography ◽  
Chromatographic Determination ◽  
Solvent System ◽  
Complete Separation ◽  
Flame Photometric Detector ◽  
Root Crops ◽  
Photometric Detector

Abstract Residue analysis of the herbicide ametryn (2-methyIthio-4-ethylamino-s-isopropylamino-s-triazine) is widely known but an analytical method for determining its metabolites has not yet been reported in the literature. A method has been developed for the extraction and determination of ametryn and 3 metabolites, 2-methylthio-4-amino-6-isopropylammo- s-triazine (GS-11354), 2-methylthio-4,6-diamino-.s-triazine(GS- 26831), and 2-methylthio-4-amino-6-ethylamino-s-triazine (GS-11355) in taniers, yams, cassava. Residues were extracted from crops with ethyl acetate-toluene (3 + 1 v/v), using a Polytron homogenizer and anhydrous sodium sulfate added for drying. The extracts were cleaned up by automated gel permeation chromatography on Bio-Beads SX-3 gel in the same solvent system. Quantitative determination was performed by gas chromatographic (GC) analysis on a column packed with 5% DEGS-PS on 100-120 mesh Supelcoport using either an N-P detector or a flame photometric detector (FPD) in the sulfur mode. Minimum detection by the flame photometric detector is 10 ng each for ametryn, GS-11354, and GS-11355 and 21 ng for GS-26831; by the N-P detector, 0.3 ng of each component gives easily quantitatable peaks. On a parts per million basis, starting with 25 g sample, the FPD detected a minimum level of 0.04 p.g/g each for ametryn, GS-11354, and GS-11355, and 0.08 p.g/g for GS-26831. The N-P detector could detect 0.0024 p.g/g for all 4 compounds. In addition to superior sensitivity, instrumental conditions allowed the complete separation of components in 10 min, for the N-P detector; more than 30 min was required for the FPD. Recoveries from fortified crops ranged from 67 to 111% at levels of 0.1-1.0 μg/g.

The production of sulphur compounds in Cheddar cheese and their significance in flavour development

1976 ◽  
Vol 43 (2) ◽  
pp. 313-320 ◽  
Author(s):  
D. J. Manning ◽  
Helen R. Chapman ◽  
Zena D. Hosking
Keyword(s):  
Cheddar Cheese ◽  
Dimethyl Sulphide ◽  
Gas Chromatograph ◽  
Sulphur Compounds ◽  
Cheese Flavour ◽  
Photometric Detector

SummaryA method is described for determining H2S, methanethiol and dimethyl sulphide in Cheddar-cheese headspace. Cheeses ranging in age from 2 to 12 months were analysed using a gas chromatograph equipped with a photometric detector. These cheeses were presented to a trained flavour panel for the assessment of quality and intensity of Cheddar cheese flavour.An attempt is made to correlate the concentration of sulphur compounds in the headspace with the average flavour scores. The results suggest that the flavour intensity of the cheese is related to the concentration of methanethiol in the headspace.

Diffusion and Mixing in Microchannel Analyzed by the Luminol Chemiluminescence

2013 ◽  
Author(s):  
Ruru Matsuo ◽  
Ryosuke Matsumoto
Keyword(s):  
Numerical Simulation ◽  
Chemical Reaction ◽  
Reaction Rate ◽  
Mixing Layer ◽  
Fluorescence Technique ◽  
Chemiluminescence Intensity ◽  
Luminol Chemiluminescence ◽  
Chemical Reaction Rate ◽  
Pdms Chip ◽  
Reaction Profile

This study focused on the diffusion and mixing phenomena investigated by using luminol chemiluminescence (CL) to estimate the local chemical reaction rate in the T-junction microchannel. Generally, the degree of mixing in microchannel is calculated by the deviation of the obtained concentration profiles from the uniform concentration profile by using fluorescence technique. Thus, the degree of mixing is a macroscopic estimate for the whole microchannel, which is inappropriate for understanding the diffusion and mixing phenomena in the mixing layer. In this study, the luminol CL reaction is applied to visualize the local chemical reaction and to estimate the local diffusion and mixing phenomena at an interface between two liquids in microchannel. Luminol emits blue chemiluminescence when it reacts with the hydrogen peroxide at the mixing layer. Experiments were carried out on the T-junction microchannel with 200 microns in width and 50 microns in depth casted in the PDMS chip. The chemiluminescence intensity profiles clearly show the mixing layer at an interface between two liquids. The experimental results are compared with the results of numerical simulation that involves solving the mass transport equations including the chemical reaction term. By calibrating CL intensity to the chemical reaction rate estimated by the numerical simulation, the local chemical reaction profile can be quantitatively estimated from the CL intensity profile.

scholarly journals The maximum chemiluminescence intensity predicts severe neutropenia in gemcitabine-treated patients with pancreatic or biliary tract cancer

2018 ◽  
Vol 82 (6) ◽  
pp. 953-960 ◽  
Author(s):  
Koki Goto ◽  
Ryusei Matsuyama ◽  
Yusuke Suwa ◽  
Sayaka Arisaka ◽  
Toshiaki Kadokura ◽  
...  
Keyword(s):  
Biliary Tract ◽  
Biliary Tract Cancer ◽  
Severe Neutropenia ◽  
Chemiluminescence Intensity ◽  
Tract Cancer

scholarly journals Determination of phenobarbital in human urine and serum usingflow injection chemiluminescence

2012 ◽  
Vol 58 (1) ◽  
pp. 88-94
Author(s):  
K. Li ◽  
L.Z. Nu ◽  
K.L. Khe ◽  
K.H. Song
Keyword(s):  
Human Urine ◽  
Pharmaceutical Preparations ◽  
Injection System ◽  
Chemiluminescence Method ◽  
Chemiluminescence Intensity ◽  
Complete Determination ◽  
Flow Injection System ◽  
Human Urine And Serum ◽  
Urine And Serum

A sensitive chemiluminescence method, based on the enhancive effect of phenobarbital on the chemiluminescence reaction between luminol and dissolved oxygen in a flow injection system, was proposed for the determination of phenobarbital. The chemiluminescence intensity responded to the concentration of phenobarbital linearly ranging from 0.05 to 10 ng⋅ml-1 with the detection limit of 0.02 ng⋅ml-1 (3σ). At a flow rate of 2.0 ml⋅min-1, a complete determination of phenobarbital, including sampling and washing, could be accomplished in 0.5 min, offering the sampling efficiency of 120 h-1 accordingly. The method was applied successfully in an assay of PB for pharmaceutical preparations, human urine and serum without any pretreatment with recovery from 95.7 to 106.7% and RSDs of less than 3.0%.

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