Interactive self-modeling mixture analysis

Second- and higher-order data generation and calibration: A tutorial

“…MCR-ALS is usually employed for quantitative 271 analytical purposes in the so-called extended mode [29], which decomposes an 272 augmented data matrix created from calibration and unknown matrices. Many different 273 constraints are available in MCR-ALS, while initial values can be efficiently estimated 274 by a variety of methods [30,31]. 275…”

Ion-molecule reactions of gas-phase chromium oxyanions: CrxOyHz− + O2

“…A multivariate curve resolution approach [43] (MCR) was employed to identify reaction pathways in an unbiased fashion. Reactant and product ion relationships, and their general kinetic behavior, were determined using the MCR method SIMPLISMA [44]. Next, a hard-modeling approach that used an alternating least squares (ALS) regression [45,46] was employed to generate concentration profiles starting from the MCR-derived kinetic model.…”

Monte Carlo Algorithm for Least Dependent Non-Negative Mixture Decomposition

“…The pure variables, thus, approximately mark the regions where at least one of the spectral components is guaranteed to be independent from all others. This idea is central to several advanced chemometrics algorithms, e.g., KSFA [20], SIMPLISMA [21], IPCA [22] and SMAC [23]. Also, Band-Target Entropy Minimization (BTEM) has been recently proposed which involves an explicit (made by visual inspection) choice of spectral features (target regions) to be retained in the course of constrained optimization [24].…”