An initial estimation method using cosine similarity for multivariate curve resolution: application to NMR spectra of chemical mixtures

The Analyst ◽  
2019 ◽  
Vol 144 (20) ◽  
pp. 5986-5995 ◽  
Author(s):  
Yuya Nagai ◽  
Woon Yong Sohn ◽  
Kenji Katayama
Keyword(s):  
Prior Knowledge ◽  
Nmr Spectra ◽  
Estimation Method ◽  
Cosine Similarity ◽  
Multivariate Curve Resolution ◽  
Chemical Mixtures ◽  
Curve Resolution

Mixture spectra is decomposed into pure spectra without prior knowledge, and the MCR calculation refines the spectra and provides the concentrations.

Multivariate Curve Resolution Combined with Estimation by Cosine Similarity Mapping of Analytical Data

The Analyst ◽  
2021 ◽  
Author(s):  
Yuya Nagai ◽  
Kenji Katayama
Keyword(s):  
Analytical Data ◽  
Cosine Similarity ◽  
Multivariate Curve Resolution ◽  
Curve Resolution

We developed a multivariate curve resolution (MCR) calculation combined with the mapping of cosine similarity (cos-s) for multiple mixture spectra of chemicals. The cos-s map was obtained by calculating the...

scholarly journals Multivariate Curve Resolution for 2D Solid-State NMR spectra

2020 ◽  
Vol 92 (6) ◽  
pp. 4451-4458 ◽  
Author(s):  
Francesco Bruno ◽  
Roberto Francischello ◽  
Giovanni Bellomo ◽  
Lucia Gigli ◽  
Alessandra Flori ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Nmr Spectra ◽  
Multivariate Curve Resolution ◽  
Curve Resolution

scholarly journals Formaldehyde in Alcoholic Beverages: Large Chemical Survey Using Purpald Screening Followed by Chromotropic Acid Spectrophotometry with Multivariate Curve Resolution

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Julien A. Jendral ◽  
Yulia B. Monakhova ◽  
Dirk W. Lachenmeier
Keyword(s):  
Detection Limit ◽  
Nmr Spectra ◽  
Chromotropic Acid ◽  
Alcoholic Beverages ◽  
Multivariate Curve Resolution ◽  
Second Step ◽  
Curve Resolution ◽  
Grape Marc ◽  
Colorimetric Test ◽  
C Nmr

A strategy for analyzing formaldehyde in beer, wine, spirits, and unrecorded alcohol was developed, and 508 samples from worldwide origin were analyzed. In the first step, samples are qualitatively screened using a simple colorimetric test with the purpald reagent, which is extremely sensitive for formaldehyde (detection limit 0.1 mg/L). 210 samples (41%) gave a positive purpald reaction. In the second step, formaldehyde in positive samples is confirmed by quantitative spectrophotometry of the chromotropic acid-formaldehyde derivative combined with Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS). Calculation of UV-VIS and13C NMR spectra confirmed the monocationic dibenzoxanthylium structure as the product of the reaction and disproved the widely citedpara,para-quinoidal structure. Method validation for the spectrophotometric procedure showed a detection limit of 0.09 mg/L and a precision of 4.2–8.2% CV. In total, 132 samples (26%) contained formaldehyde with an average of 0.27 mg/L (range 0–14.4 mg/L). The highest incidence occurred in tequila (83%), Asian spirits (59%), grape marc (54%), and brandy (50%). Our survey showed that only 9 samples (1.8%) had formaldehyde levels above the WHO IPCS tolerable concentration of 2.6 mg/L.

Direct quantification of M/G ratio from 13C CP-MAS NMR spectra of alginate powders by multivariate curve resolution

2009 ◽  
Vol 344 (15) ◽  
pp. 2014-2022 ◽  
Author(s):  
Tina Salomonsen ◽  
Henrik Max Jensen ◽  
Flemming Hofmann Larsen ◽  
Stefan Steuernagel ◽  
Søren Balling Engelsen
Keyword(s):  
Nmr Spectra ◽  
Mas Nmr ◽  
Multivariate Curve Resolution ◽  
Curve Resolution ◽  
G Ratio ◽  
Cp Mas Nmr ◽  
13C Cp Mas Nmr ◽  
Direct Quantification

Weighting hyperspectral image data for improved multivariate curve resolution results

2008 ◽  
Vol 22 (9) ◽  
pp. 482-490 ◽  
Author(s):  
Howland D. T. Jones ◽  
David M. Haaland ◽  
Michael B. Sinclair ◽  
David K. Melgaard ◽  
Mark H. Van Benthem ◽  
...  
Keyword(s):  
Hyperspectral Image ◽  
Image Data ◽  
Multivariate Curve Resolution ◽  
Curve Resolution ◽  
Hyperspectral Image Data
Sign in / Sign up

Export Citation Format

Share Document