Study on Electrochemical Fingerprints and Identification of Different Varieties of Rice and Mouldy Rice by B‐Z Oscillation Reaction System

Abstract

The electrochemical fingerprints of different varieties of rice and mouldy rice were studied by Belousov‐Zhabotinskii (B‐Z) oscillation reaction system with malonic acid as dissipative material under the condition of constant temperature. The results indicated that the chemical composition of rice may influence the kinetic parameters of the B‐Z oscillation reaction, which lead to the electrochemical fingerprint characteristic parameters and the intuitive information changes obviously. The varieties of rice and mouldy rice can be identified and evaluated by the difference of the electrochemical characteristic information.

Evaluating the consistency of rice and paddy quality using four-dimensional fingerprint analysis

“…y n ), in which x i and y i represent each peak area of the sample fingerprint (SFP) and reference fingerprint (RFP), respectively. The vector cosine of the angle (y) between x and y is defined as qualitative similarity (S F ), which can be calculated using eqn (1). In order to eliminate the situation where large peaks cover up small peaks that are caused by S F , the ratio qualitative similarity S F 0 À Á parameter is defined (eqn (2)).…”

“…Rice is the seed of monocotyledon Oryza sativa (Asian rice) or Oryza glaberima (African rice). 1 Rice is the finished product of paddy that has been cleaned and hulled. Rice purchased in the market may experience quality issues such as aging and counterfeiting.…”

The Role of PEG on Pd- and Cu-Catalyzed Cross-Coupling Reactions

“…27 In 2013, the use of TBAB and PEG as a phase-transfer catalyst was examined for the coupling of heteroaryl bromides with phenylboronic acid mediated by palladium-phosphine acid complexes. 28 Souza and co-workers found that Pd/BaSO 4 (Rosemund's catalyst), a heterogeneous catalyst, allowed the ligand-free synthesis of biaryls with PEG as the solvent and it also enabled recycling of the catalytic system. 29 After studying several solvents (ethanol, H 2 O, PEG-300, and a mixture of PEG-300/H 2 O), the Suzuki-Miyaura of iodobenzene with phenylboronic acid in a mixture of PEG-300/H 2 O using K 2 CO 3 as a base occurred in 100% yield at room temperature and at 80 °C.…”

Discrimination of instant coffee by pattern recognition of chemical oscillation fingerprints

“…The B-Z oscillation chemical reactions have more than twenty elementary reaction steps in the FKN model, so it is a very sensitive system to external chemical substances. 12 The chemical oscillation ngerprints of instant coffee were measured using the B-Z chemical oscillation reaction system. The characteristic redox constituents of different brands or varieties of instant coffee react with oscillation reactants aer adding the coffee sample to the oscillation system, which involves in the consumption and regeneration of HBrO 2 , Br À , Ce 4+ and Ce 3+ .…”