Flow-based food analysis: an overview of recent contributions

2017 ◽  
Vol 9 (45) ◽  
pp. 6313-6334 ◽  
Author(s):  
Milton K. Sasaki ◽  
Fábio R. P. Rocha ◽  
Alex D. Batista ◽  
Diogo L. Rocha
Keyword(s):  
High Precision ◽  
Food Analysis ◽  
Sampling Rate ◽  
Waste Generation ◽  
Food And Beverages ◽  
Flow Systems ◽  
Reagent Consumption

Analysis of food and beverages (e.g.determination of nutrients, additives, and contaminants) is benefited by the advantages provided by flow systems such as high precision and sampling rate, as well as low reagent consumption and waste generation.

scholarly journals An eco-friendly method for analysis of sulfonamides in water samples using a multi-pumping system

2016 ◽  
Vol 94 (10) ◽  
pp. 812-817 ◽  
Author(s):  
Tiago Augusto Catelani ◽  
Karine Castoldi ◽  
Ildikó Vargáné Tóth ◽  
João Luís Machado Santos ◽  
José Luís Fontes da Costa Lima ◽  
...  
Keyword(s):  
Water Samples ◽  
Sodium Dodecylsulfate ◽  
Waste Generation ◽  
Dilute Acid ◽  
Reaction Products ◽  
Pumping System ◽  
Liquid Waveguide Capillary Cell ◽  
Reagent Consumption ◽  
Experimental Design Methodology

A new methodology for determination of sulfonamides (sulfaquinoxaline, sulfathiazole, and sulfadimethoxine) in water samples was developed by coupling an automated multi-pumping flow system (MPFS) with a liquid waveguide capillary cell (LWCC; pathlength, 100 cm) and a spectrophotometric detector. The method is based on the reaction between sulfonamides and p-dimethylaminocinnamaldehyde (p-DAC) in the presence of sodium dodecylsulfate (SDS) in dilute acid medium (hydrochloric acid), with measurement of the reaction products at 565 nm. Experimental design methodology was used to optimize the analytical conditions. The linear range obtained was 10.0–130.0 μg/L, and detection and quantification limits were 3.1 and 10.1 μg/L, respectively. The method was successfully applied to the analysis of sulfonamides in water samples. By coupling the MPFS with the LWCC, the sensitivity was enhanced, reagent consumption was low, and waste generation was minimized. The results obtained with the MPFS method were confirmed by LC–MS.

scholarly journals An Environmental Friendly Procedure for Photometric Determination of Hypochlorite in Tap Water Employing a Miniaturized Multicommuted Flow Analysis Setup

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Sivanildo S. Borges ◽  
Boaventura F. Reis
Keyword(s):  
Tap Water ◽  
Accuracy Assessment ◽  
Flow Analysis ◽  
Photometric Determination ◽  
Waste Generation ◽  
Relative Standard ◽  
Significant Difference ◽  
Leucocrystal Violet ◽  
Reagent Consumption

A photometric procedure for the determination ofClO-in tap water employing a miniaturized multicommuted flow analysis setup and an LED-based photometer is described. The analytical procedure was implemented using leucocrystal violet (LCV; 4,4′,4′′-methylidynetris (N,N-dimethylaniline), C25H31N3) as a chromogenic reagent. Solenoid micropumps employed for solutions propelling were assembled together with the photometer in order to compose a compact unit of small dimensions. After control variables optimization, the system was applied for the determination ofClO-in samples of tap water, and aiming accuracy assessment samples were also analyzed using an independent method. Applying the pairedt-test between results obtained using both methods, no significant difference at the 95% confidence level was observed. Other useful features include low reagent consumption, 2.4 μg of LCV per determination, a linear response ranging from 0.02 up to 2.0 mg L−1  ClO-, a relative standard deviation of 1.0% (n=11) for samples containing 0.2 mg L−1  ClO-, a detection limit of 6.0 μg L−1  ClO-, a sampling throughput of 84 determinations per hour, and a waste generation of 432 μL per determination.

scholarly journals Automatic Flow Procedure for the Determination of Ethanol in Wine Exploiting Multicommutation and Enzymatic Reaction with Detection by Chemiluminescence

2004 ◽  
Vol 87 (4) ◽  
pp. 920-926 ◽  
Author(s):  
Elizabeth N Fernandes ◽  
Boaventura F Reis
Keyword(s):  
Sampling Rate ◽  
Enzymatic Reaction ◽  
Alcohol Oxidase ◽  
Parameters Optimization ◽  
Official Method ◽  
Relative Standard ◽  
Significant Difference ◽  
On Line ◽  
Reagent Consumption

Abstract An automatic procedure for the determination of ethanol in wines using a flow system based on multicommutation and enzymatic reaction is described. Alcohol oxidase was immobilized on aminopropyl glass beads and packed in an acrylic column. The peroxide due to enzymatic reaction with ethanol reacted with luminol and generated the chemiluminescence radiation that was monitored by using a laboratory-made detector based on photodiodes. The system manifold comprised a set of 3-way solenoid valves controlled by a microcomputer furnished with electronic interfaces, which ran on software written in Quick BASIC 4.5 to provide facilities to perform on-line sample dilution, reagent addition, and data acquisition. After system parameters optimization, ethanol samples were processed without prior pretreatment. The following suitable features were achieved: linear response ranging from 2.5 to 25% (v/v) ethanol, relative standard deviation of 1.8% (n = 10), detection limit of 0.3% (v/v) ethanol, sampling rate of 23 determinations per hour, and low reagent consumption of 0.23 mg luminol and 7 mg hexacyanoferrate (III) per determination. When the results were compared with those obtained using the AOAC Official Method, no significant difference at the 90% confidence level was observed.

On effects of non-systematic reflections on weak-beam images of partial dislocations

1991 ◽  
Vol 49 ◽  
pp. 688-689
Author(s):  
K. Z. Botros ◽  
S. S. Sheinin
Keyword(s):  
High Precision ◽  
Stacking Fault ◽  
Important Application ◽  
Stacking Fault Energy ◽  
Sharp Peak ◽  
Weak Beam ◽  
Partial Dislocations ◽  
Deviation Parameter ◽  
Beam Diffraction

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.

Comparative assessment of informational content of the equations of F.P. Hadlock and the computer program of V.N. Demidov in determination of term of gestation and fetal weight in the III trimester of gestation

2017 ◽  
Author(s):  
E.A. Derkach , O.I. Guseva
Keyword(s):  
Computer Program ◽  
High Precision ◽  
Gestational Age ◽  
Computer Programs ◽  
Comparative Assessment ◽  
Fetal Weight ◽  
Informational Content ◽  
Third Trimester ◽  
The Third

Objectives: to compare the accuracy of equations F.P. Hadlock and computer programs by V.N. Demidov in determining gestational age and fetal weight in the third trimester of gestation. Materials: 328 patients in terms 36–42 weeks of gestation are examined. Ultrasonography was performed in 0–5 days prior to childbirth. Results: it is established that the average mistake in determination of term of pregnancy when using the equation of F.P. Hadlock made 12,5 days, the computer program of V.N. Demidov – 4,4 days (distinction 2,8 times). The mistake within 4 days, when using the equation of F.P. Hadlock has met on average in 23,1 % of observations, the computer program of V.N. Demidov — 65,9 % (difference in 2,9 times). The mistake more than 10 days, took place respectively in 51,7 and 8,2 % (distinction by 6,3 times). At a comparative assessment of size of a mistake in determination of fetal mass it is established that when using the equation of F.P. Hadlock it has averaged 281,0 g, at application of the computer program of V.N. Demidov — 182,5 g (distinction of 54 %). The small mistake in the mass of a fetus which isn't exceeding 200 g at application of the equation of F.P. Hadlock has met in 48,1 % of cases and the computer program of V.N. Demidov — 64,0 % (distinction of 33,1 %). The mistake exceeding 500 g has been stated in 18 % (F.P. Hadlock) and 4,3 % (V.N. Demidov) respectively (distinction 4,2 times). Conclusions: the computer program of V.N. Demidov has high precision in determination of term of a gestation and mass of a fetus in the III pregnancy.

scholarly journals Determination of electron backscattering coefficient of beryllium by a high-precision Monte Carlo simulation

2021 ◽  
Vol 26 ◽  
pp. 100862
Author(s):  
Abrar Hussain ◽  
Lihao Yang ◽  
Shifeng Mao ◽  
Bo Da ◽  
Károly Tőkési ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
High Precision ◽  
Backscattering Coefficient ◽  
Electron Backscattering
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