MAGNETIC NANOCOMPOSITES IN PIEZOELECTRIC SENSORS FOR DETERMINATION OF GLYPHOSATE

Piezoelectric gravimetric sensors based on magnetic nanocomposites: polymers with molecular imprints (MIP) Fe3O4@MIP N - (phosphonmethyl) - glycine have been developed. It was found that the optimal concentration ratio of template: functional monomer: cross-monomer is 1: 3: 25. The best synthesis time is 3h with constant stirring at a speed of 60 rpm and heating to 60 °C.

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A Generalized Method for Flat Plates Impact Detection and Location

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.171 ◽

2013 ◽

Vol 543 ◽

pp. 171-175

Author(s):

Jose Andrés Somolinos ◽

Rafael Morales ◽

Carlos Morón ◽

Alfonso Garcia

Keyword(s):

Signal Processing ◽

Flat Plate ◽

Acoustic Signal ◽

Experimental Results ◽

Piezoelectric Sensors ◽

Experimental Setup ◽

Flat Plates ◽

Impact Detection ◽

Timing Difference

In the last years, many analyses from acoustic signal processing have been used for different applications. In most cases, these sensor systems are based on the determination of times of flight for signals from every transducer. This paper presents a flat plate generalization method for impact detection and location over linear links or bars-based structures. The use of three piezoelectric sensors allow to achieve the position and impact time while the use of additional sensors lets cover a larger area of detection and avoid wrong timing difference measurements. An experimental setup and some experimental results are briefly presented.

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Optimal α-Oxobutyrate Concentration for Assay of α-Hydroxybutyrate Dehydrogenase Activity in Normal and Pathological Sera at 30 °C

Clinical Chemistry ◽

10.1093/clinchem/20.4.494 ◽

1974 ◽

Vol 20 (4) ◽

pp. 494-496 ◽

Cited By ~ 3

Author(s):

Leslie M Shaw ◽

Jane Gray

Keyword(s):

Myocardial Infarction ◽

Liver Disease ◽

Lactate Dehydrogenase ◽

Dehydrogenase Activity ◽

Substrate Concentration ◽

Optimal Concentration ◽

The Mean

Abstract Optimal concentration of substrate, α-oxobutyrate, for determination of α-hydroxybutyrate dehydrogenase (HBD) activity in normal and pathological sera at 30 °C (with a centrifugal analyzer) is 12 mmol/ liter. With this substrate concentration, HBD activity averaged 146% of that found with the suboptimal concentration, 3.3 mmol/liter, usually used. Furthermore, day-to-day precision was significantly better. HBD/LD ranges (LD, lactate dehydrogenase), determined for sera from patients with myocardial infarction and liver disease, did not overlap and were similar to those established by Elliot et al. [Clin. Sci. 23, 305 (1962)], who used a suboptimal α-oxobutyrate concentration of 3.3 mmol/liter at 25 °C. At 30 °C the mean HBD/LD ratios for sera from patients with myocardial infarction were most different from those for patients with liver disease when the optimal concentration of α-oxobutyrate was used.

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Determination of testosterone/epitestosterone concentration ratio in human urine by capillary electrophoresis

Steroids ◽

10.1016/j.steroids.2020.108691 ◽

2020 ◽

Vol 161 ◽

pp. 108691

Author(s):

Bairen Du ◽

Jingjing Zhang ◽

Yanjie Dong ◽

Junwei Wang ◽

Longwen Lei ◽

...

Keyword(s):

Capillary Electrophoresis ◽

Human Urine ◽

Concentration Ratio

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Determination of Antibiotics in Meat Using Bacillus stearothermophilus Spores

Journal of Food Protection ◽

10.4315/0362-028x-44.3.194 ◽

1981 ◽

Vol 44 (3) ◽

pp. 194-200 ◽

Cited By ~ 4

Author(s):

M. BIELECKA ◽

J. D. BALDOCK ◽

A. W. KOTULA

Keyword(s):

Sample Size ◽

Bacillus Stearothermophilus ◽

Test Organism ◽

Optimal Concentration ◽

Antibiotic Residues ◽

Plate Method ◽

Assay Medium ◽

Organism Growth ◽

Ph Variations

Ten parameters affecting sensitivity, accuracy and simplicity of the diffusion plate method for determining antibiotic residues in meat were evaluated with spores of Bacillus stearothermophilus as the test organism. Eight antibiotics were studied and included penicillin, bacitracin, tetracycline, chlortetracycline, oxytetracycline, streptomycin, erythromycin and neomycin. Sensitivity of the method was most influenced by concentration of inoculum, quantity of assay medium on the plate and sample size. The optimal concentration of inoculum was established as 2 × 105 spores/ml of medium, quantity of the assay medium on plate/100 mm dia., as 6 ml and quantity of sample poured on disc/12.7 mm dia., as 100 μl. The pH of the assay medium was also important to both antibiotic potency and test organism growth. The activity of streptomycin and erythromycin was the most sensitive to pH variations.

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Molecularly imprinted polymer for selective extraction and simultaneous determination of four tropane alkaloids from Przewalskia tangutica Maxim. fruit extracts using LC-MS/MS

RSC Advances ◽

10.1039/c5ra18608k ◽

2015 ◽

Vol 5 (115) ◽

pp. 94997-95006 ◽

Cited By ~ 18

Author(s):

Shaomei Zeng ◽

Yongxin She ◽

Bining Jiao ◽

Guangyang Liu ◽

Jing Wang ◽

...

Keyword(s):

Simultaneous Determination ◽

Molecularly Imprinted Polymer ◽

Tropane Alkaloids ◽

Selective Extraction ◽

Functional Monomer ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Fruit Extracts ◽

Przewalskia Tangutica

A class-specific molecularly imprinted polymer (MIP) for selectively extracting four tropane alkaloids has been prepared using anisodine, methacrylic, and trimethylolpropane trimethacrylate as template, functional monomer and crosslinker, respectively.

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