Indirect photodegradation is one of the primary approaches for the removal of pharmaceutical contaminants from water. This degradation process is dominated by chromophoric dissolved organic matter (CDOM). After illumination, CDOM produces many reactive intermediates, which can react with drug pollutants to achieve indirect photodegradation.
View Article and Find Full Text PDFWater samples were collected from the Yellow and Bohai seas during November 2013 and the chromophoric dissolved organic matter (CDOM) and nutrients concentrations were investigated, including their composition, source and distribution characteristics. CDOM was analyzed by excitation-emission matrix spectroscopy (EEMS) in combination with a parallel factor analysis (PARAFAC). Three terrestrial humic-like substances (C1, C2, and C3) and one protein-like (C4) substances were identified.
View Article and Find Full Text PDFThe composition and distribution characteristics of chromophoric dissolved organic matter(CDOM) of Changjiang Estuary and its adjacent waters in spring (March 2015) and summer (July 2015) were evaluated by excitation-emission matrix spectroscopy (EEMs) in combination with parallel factor(PARAFAC) analysis. Three humic-like components[C1(370/495 nm),C2(330/405 nm),C3(365/440 nm)] and one protein-like component[C4(295/345 nm)] were identified. The distribution patterns of the four components in spring and summer were almost the same, showing a decreasing trend from Changjiang Estuary to adjacent waters.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
September 2015
Four kinds of diatom (Chaetoceros curvisetus, Phaeodactylum tricornutum, Nitzschia closterium f. minutissima and Navicula halophile) and two kinds of dinoflagellates (Prorocentrum donghaiense and Gymnodinium) were cultured under laboratory conditions. Variations of optical properties of chromophoric dissolved organic matter (CDOM) were studied with absorption and fluorescence excitation-emission matrix spectroscopy(EEM) during growth of marine microalgae in incubation experiment.
View Article and Find Full Text PDFAn in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor (PARAFAC) analysis and CHEMTAX. The PARAFAC model was applied to fluorescence excitation-emission matrix (EEM) of 23 algae species and 12 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. Based on the 12 fluorescent components, the algae species at different growth stages were correctly classified at the division level using Bayesian discriminant analysis (BDA).
View Article and Find Full Text PDFThe distribution and estuarine behavior of fluorescent components of chromophoric dissolved organic matter in the seawater of outer Yangtze Estuary were determined by fluorescence excitation emission matrix spectra combined with parallel factor analysis. Six individual fluorescent components were identified by PARAFAC models, including three terrestrial humic-like components C1 [330 nm/390(430) nm], C2 (390 nm/480 nm), C3 (360 nm/440 nm), marine biological production component C5 (300 nm/400 nm) and protein-like components C4 (290 nm/350 nm) and C6 (275 nm/300 nm). The results indicated that C1, C2, and C3 showed a conservative mixing behavior in the whole estuarine region, especially in high-salinity region.
View Article and Find Full Text PDFDaubechies7 (db7) wavelet was selected to decompose the 3-D fluorescence spectra of 27 species of phytoplankton belonging to 22 generas of 6 divisions found in major lakes, then the scale vectors and time-series vectors were obtained as candidates for feature spectra. The third scale vector (Ca3) of db7 was chosen as feature spectra by Bayesian discriminant analysis, and the reference spectra were obtained via hierarchical cluster analysis to feature spectra. Based on the above data, a fluorescence discrimination technique was developed by multiple linear regression resolved by non-negative least squares.
View Article and Find Full Text PDFToxic effects of tributyltin (TBT) on the growth, peak diameter and photosynthetic activity (F(v)/F(m)) of fifteen predominant phytoplankton species in China coastal sea of Leptocylindru danicus, Skeletonema marinoi, Asterionella japonica, Bacilaria paxillifera, Chaetoceros debilis, Chaetoceros socialis, Thalassiosira, Amphidinium carterae, Karenia mikimotoi, Prorocentrum minimum, Gymnodinium sp., Scrippsiella trochoidea, Gymnodinium simplex, Prorocentrum triestinum and Heterosigma akashiwo were systematically studied. 96 h-EC50 of TBT were 136.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
March 2011
Biodegradabilities of several hydrocarbon biomarker groups, including isoprene, hopanes and steranes in a medium-crude oil BZ34-1 and a heavy-crude oil SZ36-1 from offshore, were determined under laboratory conditions. The results of GC-MS analysis showed that isoprene biomarkers such as pristane and phytane in both crude oils degraded obviously in 60-day experiment period. The degradation ratios of pristane and phytane in the medium-crude oil BZ34-1 reached 20.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
May 2010
In the present paper, the authors utilize the wavelet base function coiflet2 (coif2) to analyze the 3D fluorescence spectra of 37 phytoplankton species belonging to 30 genera of 7 divisions, and these phytoplankton species include common species frequently causing harmful algal blooms and most predominant algal species in the inshore area of China Sea. After the Rayleigh and Raman scattering peaks were removed by the Delaunay triangulation interpolation, the fluorescence spectra of those phytoplankton species were transformed with the coiflet2 wavelet, and the scale vectors and the wavelet vectors were candidate for the feature spectra. Based on the testing results by Bayesian analysis, the 3rd scale vectors were the best feature segments at the division level and picked out as the fluorescence division feature spectra of those phytoplankton species, and the group of the 3rd scale vectors, the 2nd and 3rd wavelet vectors were the best feature segments at the genus level and chosen as the fluorescent genus feature spectra of those phytoplankton species.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
November 2007
Chlorophyll fluorescence excitation spectra of six phytoplankton species, belonging to Bacillariophyta and Dinophyta, were dealt by fourth-derivative analysis with the Matlab program. The results show that between 350 nm and 550 nm six fluorescence peaks were found in the fourth-derivative spectra, which are representatives of non-pigments, chlorophylls and carotenoides respectively. The method makes Bacillariophyta and Dinophyta more distinguishable when the fourth-derivative spectra are compared with the chlorophyll fluorescence excitation spectra.
View Article and Find Full Text PDFFluorescence discrimination technology for 11 species of the Red Tide algae at genus level was constructed by principle component analysis and non-negative least squares. Rayleigh and Raman scattering peaks of 3D fluorescence spectra were eliminated by Delaunay triangulation method. According to the results of Fisher linear discrimination, the first principle component score and the second component score of 3D fluorescence spectra were chosen as discriminant feature and the feature base was established.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
March 2007
The synchronous fluorescence spectra of five phytoplankton species growing under three temperatures (25, 20 and 15 degrees C)and three illuminations (7000, 4100 and 1100 Lx)were measured and processed by multinomial smoothness and autoscaling to obtain the characteristic spectra. Principal component analysis was used to obtain standard spectra. The analysis shows that at different temperatures, the characteristic spectra of Skeletonema costatuma, Isochrysis galbana, and Platymonas helgolanidica show high similarities, while the spectra similarities of Alexandrium tamarense and Gymnodinium stein are not as good as the above three species.
View Article and Find Full Text PDFChip-based capillary electrophoresis (chip-CE) is under rapid progress due to its high efficiency, fast separation, little sample consumption and integration. Due to the short optical path (30-50 microm), the conventional UV absorbance cannot satisfy the chip detection needs. Atomic fluorescence spectrometer (AFS) is a selective and sensitive detector for hydride-forming elements.
View Article and Find Full Text PDFA novel method for speciation analysis of inorganic arsenic was developed by on-line hyphenating microchip capillary electrophoresis (chip-CE) with hydride generation atomic fluorescence spectrometry (HG-AFS). Baseline separation of As(III) and As(V) was achieved within 54 s by the chip-CE in a 90 mm long channel at 2500 V using a mixture of 25 mmol l(-1) H3BO3 and 0.4 mmol l(-1) CTAB (pH 8.
View Article and Find Full Text PDFThis paper represents the first study on direct interfacing of microfluidic chip-based capillary electrophoresis (chip-CE) to a sensitive and selective detector, atomic fluorescence spectrometry (AFS) for rapid speciation analysis. A volatile species generation technique was employed to convert the analytes from the chip-CE effluent into their respective volatile species. To facilitate the chip-CE effluent delivery and to provide the necessary medium for subsequent volatile species generation, diluted HCl solution was introduced on the chip as the makeup solution.
View Article and Find Full Text PDFA protocol of producing multiple polymeric masters from an original glass master mold has been developed, which enables the production of multiple poly(dimethylsiloxane) (PDMS)-based microfluidic devices in a low-cost and efficient manner. Standard wet-etching techniques were used to fabricate an original glass master with negative features, from which more than 50 polymethylmethacrylate (PMMA) positive replica masters were rapidly created using the thermal printing technique. The time to replicate each PMMA master was as short as 20 min.
View Article and Find Full Text PDFA simple and easy-to-use integrated laser-induced fluorescence detector for microchip electrophoresis was constructed and evaluated. The fluid channels and optical fiber channels in the glass microchip were fabricated using standard photolithographic techniques and wet chemical etching. A 473 nm diode-pumped laser was used as the excitation source, and the collimation and collection optics and mirrors were discarded by using a multimode optical fiber to couple the excitation light straight into the microchannel and placing the microchip directly on the top of the photomultiplier tube.
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