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1.
ScientificWorldJournal ; 2012: 398765, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22566768

RESUMO

Study on plant diversity is the base of woodland conservation. The Guancen Mountains are the northern end of Luliang mountain range in North China. Fifty-three quadrats of 10 m × 20 m of woodland communities were randomly established along an altitudinal gradient. Data for species composition and environmental variables were measured and recorded in each quadrat. To investigate the variation of woodland communities, a Two-Way Indicator Species Analysis (TWINSPAN) and a Canonical Correspondence Analysis (CCA) were conducted, while species diversity indices were used to analyse the relationships between species diversity and environmental variables in this study. The results showed that there were eight communities of woodland vegetation; each of them had their own characteristics in composition, structure, and environment. The variation of woodland communities was significantly related to elevation and also related to slope, slope aspect, and litter thickness. The cumulative percentage variance of species-environment relation for the first three CCA axes was 93.5%. Elevation was revealed as the factor which most influenced community distribution and species diversity. Species diversity was negatively correlated with elevation, slope aspect, and litter thickness, but positively with slope. Species richness and heterogeneity increased first and then decreased but evenness decreased significantly with increasing elevation. Species diversity was correlated with slope, slope aspect, and litter thickness.


Assuntos
Altitude , Biodiversidade , Árvores/fisiologia , China , Meio Ambiente , Geografia , Método de Monte Carlo , Análise Multivariada , Temperatura
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(4): 705-11, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12609618

RESUMO

The interaction of sparfloxacin with HP-beta-cyclodextrin (HP-beta-CD) has been studied by several analytical techniques, including 1H NMR, fluorescence spectroscopy, infrared spectroscopy, thermal analysis and scanning electron microscopy. In this paper, solid inclusion complex of sparfloxacin with HP-beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, infrared, differential scanning calorimetry and 1D, 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of sparfloxacin with HP-beta-CD. The formation constant of complex was determined by the fluorescence method and 1H NMR. Spacial configuration of complex has been proposed on 2D NMR technique.


Assuntos
Ciclodextrinas/análise , Ciclodextrinas/química , Fluoroquinolonas/análise , Fluoroquinolonas/química , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Antituberculosos/análise , Antituberculosos/química , Varredura Diferencial de Calorimetria , Relação Dose-Resposta a Droga , Excipientes/análise , Excipientes/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Modelos Químicos , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Temperatura
3.
Artigo em Inglês | MEDLINE | ID: mdl-14747100

RESUMO

The interaction of ciprofloxacin with HP-beta-cyclodextrin (HP-beta-CD) has been studied by several analytical techniques, including 1H nuclear magnetic resonance (NMR), 13C NMR, fluorescence spectra, infrared spectroscopy, thermal analyzer and scanning electron microscope. In this paper, solid inclusion complex of ciprofloxacin with HP-beta-CD was synthesized by the coprecipitation method. In addition, the characterization of the inclusion complex has been proved by fluorimetry, infrared, differential scanning calorimetry and one-dimensional (1D), 2D NMR. The experimental results confirmed the existence of 1:1 inclusion complex of ciprofloxacin with HP-beta-CD. The formation constant of complex was determined by fluorescence method and 1H NMR. Spacial configuration of complex has been proposed on two-dimensional NMR technique.


Assuntos
Ciprofloxacina/química , Ciclodextrinas/química , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Varredura Diferencial de Calorimetria , Ciprofloxacina/metabolismo , Ciclodextrinas/metabolismo , Fluorometria , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho
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