Standard Calibration Method Based on MPPC Detector Model

2016 ◽  
Vol 22 (3) ◽  
pp. 202-208
Author(s):  
丁承洁 DING Cheng-jie ◽  
陈修亮 CHEN Xiu-liang ◽  
史学舜 SHI Xue-shun ◽  
刘长明 LIU Chang-ming ◽  
武愕 WU E
Keyword(s):  
Calibration Method ◽  
Standard Calibration ◽  
Detector Model

scholarly journals Multibranch Gold Nanoparticles as Surface-Enhanced Raman Spectroscopy Substrates for Rapid and Sensitive Analysis of Fipronil in Eggs

Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5354 ◽  
Author(s):  
Haonuan Zhao ◽  
Dandan Huang ◽  
Shuhua Zhu
Keyword(s):  
Gold Nanoparticles ◽  
Raman Spectroscopy ◽  
Calibration Method ◽  
Surface Enhanced Raman Spectroscopy ◽  
Oriented Growth ◽  
Low Surface Energy ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Standard Calibration ◽  
Optimized Conditions

A sensitive strategy to rapidly detect fipronil residues in eggs using multibranch gold nanoparticles (AuNPs) as the substrate of surface-enhanced Raman spectroscopy (SERS) was investigated in this study. Under optimized conditions, fipronil molecules preferentially deposited on the multibranch gold nanoparticles with preferential (111) facet-oriented growth due to its low surface energy. This anisotropic growth promoted the increase of SERS “hot spots”, inducing a huge enhancement of Raman signals of the fipronil. An external standard calibration method was employed for quantitative analysis, and the method was validated for linearity, sensitivity, repeatability and recovery. Good linearity were found in the concentration range of 10 ng/L~10 mg/L in fipronil acetone solution (R2 = 0.9916) and 8 × 10−5 mg/m2 to 0.8 mg/m2 on eggshells (R2 = 0.9906), respectively. The recovery rate based on acetone recovered fipronil on eggshells and in egg liquids was 80.13%~87.87%, and 81.34%~88.89%, respectively. The SERS assay was successfully used to monitor fipronil in eggs.

scholarly journals Determination of Trace and Heavy Metals in Fruit Juices in the Romanian Market

2020 ◽  
Vol 77 (2) ◽  
pp. 125
Author(s):  
Florin Dumitru BORA ◽  
Anamaria CĂLUGĂR ◽  
Claudiu Ioan BUNEA ◽  
Ionut RACZ
Keyword(s):  
Heavy Metals ◽  
Calibration Method ◽  
Fruit Juices ◽  
Trace Heavy Metals ◽  
Icp Ms ◽  
Metal Contents ◽  
External Standard ◽  
Standard Calibration ◽  
Peach Juice

The presence of trace, heavy metals in foodstuffs is of intense public interest. The aim of this study was to determine the metal contents in most known commercial fruit juices present on the Romanian market. The multielement analysis was made using the ICP-MS technique, after appropriate dilution, using the external standard calibration method. Multifruit, mango, and kiwi juice have recoded the highest concentration of Cu, while apple and pear juice has recoded the lowest concentration, and in the case of Zn, peach juice has recoded the highest concentration. Concerning Pb, Cd, and As concentration, apple, peach, and multifruit juices recorded the highest levels of concentration. The concentration of Zn, Cu, Co, and As generally, was higher in the juice samples packed in boxes, while Ni, Cr, Pb, and Cd recorded the highest values in the juice packed in plastic bottles.

Headspace Gas Chromatographic Estimation of Some Yogurt Volatiles

1991 ◽  
Vol 74 (4) ◽  
pp. 630-634 ◽  
Author(s):  
Franz Ulberth
Keyword(s):  
Accurate Determination ◽  
Standard Addition ◽  
Calibration Method ◽  
Relative Standard ◽  
Headspace Gas ◽  
Standard Calibration ◽  
Gas Chromatographic Method ◽  
Aroma Components ◽  
Ppm Level

Abstract A headspace gas chromatographic method Is described for the determination of acetaldehyde, ethanol, acetone, dlacetyl, and 2-butanone In yogurt. Yogurt (2 g) is equilibrated 1 h in a 10 mL vial at 60 °C, and 0.25 mL headspace gas Is splitinjected. The volatiles are baseline-separated In less than 5 min by using a thick film capillary column coated with SE-54. An external standard calibration method fulfills the requirements for an accurate determination of the yogurt aroma components. The accuracy of this method was checked by the standard addition method. The precision of the method, In terms of the relative standard deviation, depends on the analyte concentration. At the 10 ppm volatile level, RSD Is 2%, and at the 0.1 ppm level, 15%.

The Circular Gap Couette Flow Modeling

2016 ◽  
Vol 11 (4) ◽  
pp. 52-60
Author(s):  
Vadim Lebiga ◽  
Vitaliy Zinoviev ◽  
Alexey Pak ◽  
Ivan Zharov
Keyword(s):  
Couette Flow ◽  
Rarefied Gas ◽  
Calibration Method ◽  
Calibration Data ◽  
Flow Modeling ◽  
Flow Parameters ◽  
Profile Deviation ◽  
Experimental Implementation ◽  
Geometry Configuration ◽  
Standard Calibration

The simulation of Couette flow inside the circular gap between coaxial cylinders is observed due to the difficulty of the experimental implementation of the equal plane one, especially for rarefied gas conditions and high Knudsen numbers. Geometry configuration of the experimental facility have been defined in order to minimize speed profile deviation inside the gap from linear shape, existing in case of laminar flow and preventing appearance of Taylor – Gërtler vortexes with chosen flow parameters. The previous stage, that was conducted using the hot-wire anemometer in atmosphere pressure conditions has shown the efficiency of the facility and sufficient agreement of calibration data, received using considered calibration method and data of standard calibration approach when the model wind tunnel DISA is applied.

scholarly journals In Situ Calibration of Hot-Film Probes Using a Collocated Sonic Anemometer: Implementation of a Neural Network

2010 ◽  
Vol 27 (1) ◽  
pp. 23-41 ◽  
Author(s):  
E. Kit ◽  
A. Cherkassky ◽  
T. Sant ◽  
H. J. S. Fernando
Keyword(s):  
Neural Network ◽  
Sonic Anemometer ◽  
Input Voltage ◽  
Calibration Method ◽  
Calibration Procedure ◽  
Approximation Technique ◽  
Sonic Anemometers ◽  
Standard Calibration ◽  
Hot Film

Abstract Although the integral quantities of atmospheric turbulence are conveniently measured using sonic anemometers, obtaining relevant finescale variables such as the kinetic energy dissipation using conventional hot-film/wire techniques remains a challenge because of two main difficulties. The first difficulty is the mean wind variability, which causes violation of the requirement that mean winds have a specific alignment with the hot-film/wire probe. To circumvent this problem, a combination of collocated sonic and hot-film anemometers, with the former measuring mean winds and aligning the latter in the appropriate wind direction via an automated platform, is successfully designed and implemented. The second difficulty is the necessity of frequent and onerous calibrations akin to hot-film anemometry that lead to logistical difficulties during outdoor (field) measurements. This is addressed by employing sonic measurements to calibrate the hot films in the same combination, with the output (velocity) to input (voltage) transfer function for the hot film derived using a neural network (NN) model. The NN is trained using low-pass-filtered hot-film and sonic data taken in situ. This new hot-film calibration procedure is compared with the standard calibration method based on an external calibrator. It is inferred that the sonic-based NN method offers great potential as an alternative to laborious standard calibration techniques, particularly in the laboratory and in stable atmospheric boundary layer settings. The NN approximation technique is found to be superior to the conventionally used polynomial fitting methods when used in conjunction with unevenly spaced calibration velocity data generated by sonic anemometers.

Collaborative Study of Three Methods for Determination of Aflatoxin in Peanuts and Peanut Products

1970 ◽  
Vol 53 (1) ◽  
pp. 104-113
Author(s):  
A E Waltking
Keyword(s):  
Peanut Butter ◽  
Collaborative Study ◽  
Method Comparison ◽  
Peanut Meal ◽  
Calibration Method ◽  
Silica Gels ◽  
Tlc Plates ◽  
Standard Calibration ◽  
Aoac Official

Abstract A collaborative study directly comparing the proposed BF method with the two AOAC official first action methods for aflatoxin in peanut products (commonly designated as the CB and t he Celite methods) was carried out on both naturally contaminated ground peanuts and specially prepared peanut butters, as well as commercial peanut butter and peanut meal to which known amounts of the anatoxins were added. Included in the study were: comparisons of a proposed variation in the CB method; a study of silica gels used for the cleanup step of the CB method; comparison of the visual and instrumental evaluation of the TLC plates; and a spectrophotometric procedure for calibration of the standards. Statistical evaluation of t h e results indicated that no advantage was obtainable through the proposed revision in the CB method nor in the use of a common silica gel lot for t h e cleanup column. The standard calibration method was shown to be both accurate and precise and instrumental evaluations of the TLC plates were shown to be more precise than visual determinations. In addition to being faster and more convenient and requiring less reagents,the BF method was equal to the official methods with respect to between-and withinlaboratory precision and accuracy.

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