Publications by authors named "Zhi-feng Cui"

The trace element of Manganese element in the agricultural farm (Anhui Huaiyuan Nongkang) soil was quantitatively analyzed by Laser-induced breakdown spectroscopy. The line of 403.1 nm was selected as the analysis line of Mn.

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Three feature extraction algorithms, such as the principal component analysis (PCA), the discrete cosine transform (DCT) and the non-negative factorization (NMF), were used to extract the main information of the spectral data in order to weaken the influence of the spectral fluctuation on the subsequent quantitative analysis results based on the SERS spectra of the pesticide thiram. Then the extracted components were respectively combined with the linear regression algorithm--the partial least square regression (PLSR) and the non-linear regression algorithm--the support vector machine regression (SVR) to develop the quantitative analysis models. Finally, the effect of the different feature extraction algorithms on the different kinds of the regression algorithms was evaluated by using 5-fold cross-validation method.

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Overexpression of pleiotropic drug resistance (PDR) efflux pumps of the ATP-binding cassette (ABC) transporter superfamily is the major cause of fungal multi-drug resistance and decreased efficacy of antifungal drugs. This review focused on recent progresses in understanding of the PDR efflux pumps of ABC transporter superfamily in Saccharomyces cerevisiae and the fungal pathogens Candida albicans, Cryptococcus neoformans, and Aspergillus fumigates. The mechanisms underlying efflux pump-mediated drug resistance and the regulatory networks involved were discussed.

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Article Synopsis
  • Environmental concerns regarding heavy metal pollution in seawater have prompted research into effective monitoring techniques.
  • The study explored the use of laser induced breakdown spectroscopy (LIBS) to detect metal ions in water solutions, focusing on optimizing conditions for better detection.
  • Results indicated that while LIBS shows promise for identifying toxic metals like copper and lead, further enhancements are needed to improve detection limits for practical ocean monitoring applications.
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The pyridyl-lead complexes [Pb(m)-C5H4N](-) (m = 1-4), which are produced from the reactions between lead clusters formed by laser ablation and the pyridine molecules seeded in argon carrier gas, are studied by photoelectron (PE) spectra and density functional theory. The adiabatic electron affinity (EA) of [Pb(m)C5H4N](-) is obtained from PE spectra at photon energies of 308 and 193 nm. Theoretical calculation is carried out to elucidate their structures and bonding modes.

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Knowledge of the ratios between different polarizability betai'j'k' tensor elements of a chemical group in a molecule is crucial for quantitative interpretation and polarization analysis of its sum frequency generation vibrational spectroscopy (SFG-VS) spectrum at interface. The bond additivity model (BAM) or the hyperpolarizability derivative model along with experimentally obtained Raman depolarization ratios has been widely used to obtain such tensor ratios for the CH3, CH2, and CH groups. Successfully, such treatment can quantitatively reproduce the intensity polarization dependence in SFG-VS spectra for the symmetric (SS) and asymmetric (AS) stretching modes of CH3 and CH2 groups, respectively.

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On the basis of the spectrum term of a electronic rotational-vibrational energy level, the law of vibrational band sequences and progressions in diatomic molecules was analysed. According to the law, the Deslandres table and its nature were summarized. How to indicate the measured values of a electronic-vibrational spectrum was illustrated by taking the Swan band spectra of the C2 molecule as an example.

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