Search Results - "BETTENCOURT DA SILVA, Ricardo J. N"

Bottom-Up Evaluation of the Uncertainty of the Quantification of Microplastics Contamination in Sediment Samples by Morgado, Vanessa, Palma, Carla, Bettencourt da Silva, Ricardo J. N.

“…The quantification and comparison of microplastic contamination of sediments are affected by sample heterogeneity and the systematic and random effects…”
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Determination of river water composition trends with uncertainty: Seasonal variation of nutrients concentration in Tagus river estuary in the dry 2017 year by Borges, Carlos, Bettencourt da Silva, Ricardo J.N., Palma, Carla

“…The assessment of long-term trends in river water composition is hampered by river composition heterogeneity, and sampling and sample analysis uncertainty…”
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Standard addition method with cumulative additions: Monte Carlo uncertainty evaluation by Dadamos, Tony R.L., Damaceno, Airton J., Fertonani, Fernando L., Bettencourt da Silva, Ricardo J.N.

“…The cumulative standard addition method allows the calibration of an instrument affected by matrix effects when a small sample volume is available. Recently,…”
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Development and validation of a grouping method for pesticides analysed in foodstuffs by Bettencourt da Silva, Ricardo J.N., Dias, Pedro M.V.B.F., Camões, Maria Filomena G.F.C.

“…► Selection of representative pesticides for the simplification of method validation. ► Grouping pesticide according to the equivalence of the pattern of their…”
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Designing valid and optimised standard addition calibrations: Application to the determination of anions in seawater by Rodrigues, Joana, da Silva, Ricardo J.N. Bettencourt, Camões, M. Filomena G.F.C., Oliveira, Cristina M.

“…A strategy for designing valid standard addition calibrations and for optimising their uncertainty is presented. The design of calibrations involves the…”
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Validated spreadsheet for the identification of PE, PET, PP and PS microplastics by micro-ATR-FTIR spectra with known uncertainty by Morgado, Vanessa, Gomes, Luís, Bettencourt da Silva, Ricardo J.N., Palma, Carla

“…The monitoring of microplastics in the environment is crucial to determine the relevance and trends of this contamination necessary to plan environmental…”
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Optimization of the determination of chemical oxygen demand in wastewaters by Silva, Alexandra M.E. Viana da, Silva, Ricardo J.N. Bettencourt da, Camões, M. Filomena G.F.C.

“…Variation of the percentage contribution, P j , of the major uncertainty components, of the measurement expanded uncertainty ( U) and of the target measurement…”
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Microplastics contamination in sediments from Portuguese inland waters: Physical-chemical characterisation and distribution by Morgado, Vanessa, Gomes, Luís, Bettencourt da Silva, Ricardo J.N., Palma, Carla

“…Plastics are the major constituent of waste accumulated in inland waters and subsequently transferred to the ocean. The smaller plastic particles, typically…”
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Compatibility of activity coefficients estimated experimentally and by Pitzer equations for the assessment of seawater pH by Anes, Bárbara, Bettencourt da Silva, Ricardo J. N., Martins, Hugo F. P., Oliveira, Cristina S., Camões, M. Filomena

“…Calibration of pH meters is usually performed with reference pH buffer solutions of low ionic strength, I  ≤ 0.1 mol kg −1 . For seawater pH measurements ( I…”
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Weighted calibration with reduced number of signals by weighing factor modelling: Application to the identification of explosives by ion chromatography by Brasil, Beatriz, Bettencourt da Silva, Ricardo J.N., Camões, M. Filomena G.F.C., Salgueiro, Pedro A.S.

“…•Reliable linear weighted calibrations, based in reduced number of signal, are performed.•Simplification of weighted calibrations is based in prior models of…”
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Statistically sound identification of compounds by low-resolution GC-MS: Identification of tear agents in tear gas sprays by Salgueiro, Pedro A.S., Ricardo J.N., Bettencourt da Silva

“…Gas-chromatography hyphenated with low-resolution mass spectrometry is a very flexible tool for the cost-effective identification and quantification of…”
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Simplified and Detailed Evaluations of the Uncertainty of the Measurement of Microbiological Contamination of Pharmaceutical Products by Lourenço, Felipe Rebello, Bettencourt da Silva, Ricardo J N

“…The control of the microbial contamination of pharmaceutical products (PP) is crucial to ensure their safety and efficacy. The validity of the monitoring of…”
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Determination of microplastic contamination levels and trends in vast oceanic sediment areas with uncertainty by Morgado, Vanessa, Palma, Carla, Bettencourt da Silva, Ricardo J.N.

“…Small plastic particles, designated as microplastics, are known vehicles of several contaminants desorbed from their surface after being ingested by marine…”
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Development and validation of statistically sound criteria for the match of unweathered GC-MS fingerprints in oil spill forensics by Rocha, Ana Catarina, Palma, Carla, Bettencourt da Silva, Ricardo J.N.

“…The investigation of an oil spill's origin frequently relies on determining the equivalence of oil component patterns in samples from the contaminated…”
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Monte Carlo bottom-up evaluation of global instrumental quantification uncertainty: Flexible and user-friendly computational tool by Morgado, Vanessa, Palma, Carla, Bettencourt da Silva, Ricardo J.N.

“…Many instrumental methods of analysis require the daily collection of calibrator signals to calibrate their response. The quality of quantifications based on…”
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Microplastics identification by infrared spectroscopy – Evaluation of identification criteria and uncertainty by the Bootstrap method by Morgado, Vanessa, Palma, Carla, Bettencourt da Silva, Ricardo J.N.

“…The assessment of microplastic contamination in an environmental compartment involves identifying and counting microplastics in a representative fraction of…”
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Bottom-up uncertainty evaluation of complex measurements from correlated performance data: Determination of total Cr in yeast by ICP-MS after acid digestion by Pluháček, Tomáš, Pechancová, Radka, Milde, David, Bettencourt da Silva, Ricardo J.N.

“…[Display omitted] •Analyte recovery assessed from spiked yeast and certified reference material analyses.•Estimated recovery correlated from quantifications…”
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Risk of false conformity decisions of multicomponent items controlled by correlated measurement results due to the sharing of analytical steps by Lourenço, Felipe R., Bettencourt da Silva, Ricardo J.N.

“…The assessment of the conformity of some items, such as medicines, food products or drinking waters, with limits set for several of their components, involves…”
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Evaluation of seawater composition in a vast area from the Monte Carlo simulation of georeferenced information in a Bayesian framework by Borges, Carlos, Palma, Carla, Dadamos, Tony, Bettencourt da Silva, Ricardo J.N.

“…The detection of composition or pollution trends of vast environmental water areas, from a river, lake or sea, requires the determination of the mean…”
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Statistically sound comparison of standardized and simulation methods for oil spill source identification in real spill scenarios by Rocha, Ana Catarina, Bettencourt da Silva, Ricardo J.N., Palma, Carla

“…The comparison of oil patterns of a spill (Sp) and suspected spill source (SS) samples is based on ratios between correlated GC–MS signals of…”
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