Search results for "Calibration"
showing 10 items of 890 documents
Calibration transfer in chemiluminescence analysis
2001
Abstract Direct standardization (DS) and piecewise direct standardization (PDS) methods are applied to multivariate standardization of chemiluminescence signals using PLS model as the calibration model. The linear concentration interval of the chemiluminescence determination was determined. This interval was located using univariate robust calibration by least median of squares (LMS) method. The linear calibration model was corroborated by conventional least-squares method. The standardization subset and window size were optimized by means of the prediction residual error sum of squares. Several instrumental sources of variability have been studied: the detection cell, instrument, batch ver…
Calibrations and isoperimetric profiles
2007
We equip many noncompact nonsimply connected surfaces with smooth Riemannian metrics whose isoperimetric profile is smooth, a highly nongeneric property. The computation of the profile is based on a calibration argument, a rearrangement argument, the Bol-Fiala curvature dependent inequality, together with new results on the profile of surfaces of revolution and some hardware know-how.
FPGA implementation of a deep learning algorithm for real-time signal reconstruction in particle detectors under high pile-up conditions
2019
The analog signals generated in the read-out electronics of particle detectors are shaped prior to the digitization in order to improve the signal to noise ratio (SNR). The real amplitude of the analog signal is then obtained using digital filters, which provides information about the energy deposited in the detector. The classical digital filters have a good performance in ideal situations with Gaussian electronic noise and no pulse shape distortion. However, high-energy particle colliders, such as the Large Hadron Collider (LHC) at CERN, can produce multiple simultaneous events, which produce signal pileup. The performance of classical digital filters deteriorates in these conditions sinc…
Calibration and Validation
2016
The aim of this chapter is to summarise the problems incurred during the phases of calibrating and validating the extortion racket models used by the GLODERS project. The chapter starts with the discussion of the data availability and summarises shortly the contents of Sect. 4.3. It continues with a discussion of what parameterisation, calibration, sensitivity analysis and validation have to do with each other and ends up with a discussion of the validity of the GLODERS models.
Calibration and validation of activated sludge model No.2d for Spanish municipal wastewater.
2002
Activated Sludge Model No. 2d (ASM2d) was validated with data obtained from pilot scale plant treating municipal wastewater from the city of Valencia (Spain). First of all, ASM2d was calibrated using experimental data from anaerobic, anoxic and aerobic batches. A set of kinetic and stoichiometric parameters resulted from these assays. Differences between the values obtained and default values proposed in ASM2d can be explained by the presence of glycogen accumulating organisms (GAOs). The calibrated model was then used to simulate results from a pilot plant. Simulation using the set of parameters obtained accurately reproduces experimental results. This paper also presents a detailed proced…
In-situ suspended aggregate microextraction: A sample preparation approach for the enrichment of organic compounds in aqueous solutions.
2015
Abstract This work presents in-situ suspended aggregate microextraction (iSAME) as a new and expedient sample preparation method. This new concept capitalizes on the general principles of in-situ solvent formation microextraction, in the sense that extraction is carried out in a supramolecular aggregate phase, which is formed in-situ in the sample through one-step process involving ion-association between a cationic surfactant and a benzene sulfonic acid derivative. The suspended aggregate containing the analytes is then collected in the form of a thin-film on the surface of a common filter paper by suction filtration. The entrapped analytes are released by completely dissolving the thin-fi…
Application of integrative cloud point extraction and concentration for the analysis of polyphenols and alkaloids in mulberry leaves
2018
Abstract A simple and efficient method based on cloud point extraction and concentration combined with high performance liquid chromatography was developed for the simultaneous separation and determination of five target compounds (deoxynojirimycin, chlorogenic acid, rutin, isoquercitrin and astragalin) in mulberry leaves samples. Firstly, to obtain a high extraction rate, the ultrasound assisted extraction was developed on acid modified Triton X-114 system. Under the optimal conditions, the total maximum extraction yields of five target compounds reached 20.80 mg/g, which was superior to conventional solvent extraction. After the cloud point extraction and concentration, the HPLC analysis …
A chamber to test the response of radon detectors to changing environmental conditions.
2011
Radon risk assessment is carried out with accurate measurements with active or passive instrumentation. All radon detectors must be calibrated and tested using a radon chamber containing a known concentration of radon produced by specific sources of 226Ra. Some of the chambers can also be used to test the response of detectors as a function of environmental conditions. In this case, it can be inferred a calibration curve with respect to changing of the parameter considered. For this aim, a new chamber radon was designed and realized to perform both calibration of instruments and to study the detector response in a large range of variation of the environmental parameters (pressure, 700 - 110…
Multi-elemental determination of heavy elements in plastics using X-ray fluorescence after destruction of the polymer by molten sodium hydroxide
1992
In this paper a method is proposed for the multielemental analysis of Sb(III), Ba, Cd, Cr(III), Hg, Pb and As(III) in plastics, using X-ray fluorescence after alkaline decomposition and preconcentration by (co)precipitation. The organic matrix is destroyed by decomposition with sodium hydroxide melted in a silver crucible by the open system technique, using sodium nitrate as auxiliary oxidant. The variables which influence preconcentration are optimized: digestion time, pH, salinity, carrier and sodium diethyldithiocarbamate (DDTC) and sodium rhodizonate (R) as precipitants. The calibration curves were linear up to 200 μg of the element present, except for lead (150 μg) antimony(III) (100 μ…
Fluxapyroxad Haptens and Antibodies for Highly Sensitive Immunoanalysis of Food Samples
2017
Fluxapyroxad is a new-generation carboxamide fungicide, with residues increasingly being found in food samples. Immunochemical assays have gained acceptance in food quality control as rapid, cost-effective, sensitive, and selective methods for large sample throughput and in situ applications. In the present study, immunoreagents to fluxapyroxad were obtained for the first time, and competitive immunoassays were developed for the sensitive and specific determination of fluxapyroxad residues in food samples. Two carboxyl-functionalized analogues of fluxapyroxad were prepared, and antibodies with IC50 values in the low nanomolar range were generated from both haptens, though a dissimilar respo…