The Research On Multi-way Chemometric Methodologies And Their Applications In Pesticide Analysis

Chemometrics is a developing composite discipline. It uses the methods of mathematics, statistics and computer sciences to extracting the optimal scheme for chemical measurements and to elucidating the data collected from chemical measurements. There are two important aspects in study on chemometrics: one is the research on basic theories and methods, another is on applications of chemometrics to chemistry and relative scientific fields.The author has been analyzing carefully the development direction and the research focus of chemometrics, and carried out the research on multi-way chemometric methodologies and their applications. With the development of high-order analytical instrumentation, multi-way data analysis has become an active domain with practical significance. Chemometric methodologies not only comprehensively expand the fundamental theory of modern analytical chemistry, but also provide a variety of powerful techniques for direct and on-line analysis of complex chemical systems, which are generally hard to handle by conventional analytical techniques.Studies presented in the thesis primarily deals with the following aspects of multi-way data analysis in chemometrics.1. The multilinear component model (Chapter 2):In order to further understand the decomposition algorithms based on multilinear component model and the applications of these algorithms in practice, it is necessary to realize and explore the characteristics and advantages of multilinear decomposition algorithms. Based on the mathematical and graphic expressions of multilinear component model, the nature of these decomposition algorithms were analyzed in details. The algorithms of multi-way arrays and methodologies provide interesting hints to develop multilinear algebra in mathematics.2. Application of multilinear data analysis to the study of dynamics (Chapter 3– Chapter 4):In Chapter 3 it provided a novel method to determine carbaryl and 1-naphthol in river water and tap water and used this method to investigate the hydrolysis of carbaryl. In Chapter 4 a new method to determine carbaryl in effluent was given and the hydrolysis of carbaryl in effluent with the aid of three-order calibarion was studied. Monitoring a chemical reaction is an important aspect in chemistry. But it is difficult to achieve this aim in presence of uncalibrated interference in complex system with traditional methods. It was convenient to implement the aim using the methods in this thesis and validates the power and potential of second-order calibration and three-order calibration.3. The quadrilinear decomposition method (Chapter 5):The instruments that generate quadrilinear data array are available to chemist, it is necessary to develop a quadrilinear decomposition method to analyze quadrilinear data array. It can be used to three-order calibration and it not only retains the second-order advantage of second-order calibration but also holds additional advantages. They can be defined the'third-order advantage'. However, the complete third-order advantages are still unknown. So it is pressing to explore the theory of quadrilinear decomposition and third-order advantage. In Chapter 5 a novel method, alternating asymmetric quadrilinear decomposition (AAQLD), is developed for decomposition of quadrilinear data and applied to third-order calibration. By treating simulated and real data sets, the results indicated that both AAQLD and PARAFAC work well. It was shown a much higher convergence rate compared with quadrilinear PARAFAC. Moreover, it is generally insensitive to the overestimates of the component number chosen. This offers the advantage that in third-order calibration one need not pay much attention to determining a proper component number for the model, and it is difficult for quadrilinear PARAFAC to avoid it.5. The applications of three-way data analysis in Pesticide analysis (Chapter 6 to Chapter 8):Pesticides were used to control mainly harmful organisms (such as pests, pest mites, nematodes, pathogens, weeds and rodents), which harm agriculture, forestry and animal husbandry and regulate plant growth. However, there are a lot of environmental issues and public health issues for the abuse of pesticides. The issue of pesticide residue has aroused attention of many countries and international organizations. In Chapter 6 it provided a novel method to determine carbendazim, carbaryl and 1-naphthol in honey, and validate it by second-order standard addition method (SOSAM) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). In Chapter 7 with the aid of three second-order calibaration methods, parallel factor analysis (PARAFAC), selfweighted alternating trilinear decomposition (SWATLD) and alternating penalty trilinear decomposition algorithm (APTLD), quantifying carbendazim in banana was performed. In Chapter 8 a new method for determination of carbofuran in apple and banana is proposed with the aid of alternating trilinear decomposition (ATLD) coupled with excitation–emission matrix fluorescence.