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1.
Chem Biodivers ; 17(12): e2000500, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078897

RESUMO

We characterized a new cycloartane glycoside, herein known as aspleniumside F (1), along with five known compounds as kaempferol-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-galacopyranoside (2), quercetin-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (3), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (4), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (5), and kaempferol-3-O-[(6-O-p-coumaroyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (6), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat Thromboangiitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HR-ESI-MS, analyses as well as through comparisons with previous reports, its chemical structure was determined as 3ß,24,30-tri-ß-D-glucopyranosyl-23,25-dihydroxycycloartane (= (23R,24R)-3ß,24-bis-(ß-D-glucopyranosyloxy)-23,25-dihydroxy-9ß-9,19-cyclolanostan-29-yl ß-D-glucopyranoside). According to the 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 were revealed as ß-D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC50 of 12.43, 6.78, 9.12, 6.94 and 4.85 µM revealed that compounds 2-6 had bioactivity.

2.
Environ Sci Pollut Res Int ; 27(13): 15337-15349, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32077017

RESUMO

A novel catalyst of Fe-Mn/AC was prepared and used as a heterogeneous catalyst to activate O3/Na2S2O8 for landfill leachate biochemical effluent treatment. The experimental results indicated that the highest COD (84%) and color (98%) removal was obtained at Fe-Mn/AC dosage 1.2 g/L, O3 concentration 1.2 g/L, Na2S2O8 dosage 6 g/L, initial pH 10, and reaction time 100 min. Three-dimensional and excitation emission matrix (3D-EEM) fluorescence spectrometry, Fourier transform infrared spectroscopy (FTIR), and gas chromatography mass spectrometry (GC/MS) of wastewater samples before and after treatment demonstrated that the leachate biochemical effluent contained a large amount of humic and fulvic acid organic compounds. After treatment with this coupling system, both the pollution level of dissolved organic matter (DOM) and the fluorescence intensity declined. The micro morphology of Fe-Mn/AC was characterized using scanning X-ray diffraction patterns (XRD), electron microscope spectra (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. It can be concluded that the microscopic morphology of the catalyst is porous. The main active components are amorphous MnO2 and multivalent iron oxides. Furthermore, the Fe-Mn/AC catalyst showed great reusability; the removal efficiency of COD was only reduced from 84% to 79% at the fourth reaction. Moreover, the COD removal efficiency could recover to 81% after catalyst regeneration.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Compostos de Manganês , Compostos Orgânicos , Oxirredução , Óxidos
3.
Opt Express ; 27(5): 7344-7353, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876299

RESUMO

Multiple-path interference plays a fundamental role in classical and quantum physics. In this work, we propose two general schemes to realize multiple electromagnetically induced transparency (EIT) and electromagnetically induced absorption (EIA) in coupled microresonators and optomechanical systems. We give explicit physical descriptions and find out that these two schemes are essentially equivalent to each other. More importantly, we experimentally demonstrate both multiple EIT and EIA by coupling a microtoroid to a microsphere that supports multiple high Q optical modes with dense modes distributions. The theory fits well with the experimental results. We believe that our study and experimental results lay a foundation for realizing arbitrary multiple pathways interference in applications.

4.
Opt Express ; 27(1): 63-73, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30645359

RESUMO

We have studied the effect of geometry deformation on the mechanical frequencies and quality factors for different modes in the Whispering Gallery Mode (WGM) microresonators, that is unavoidable in the practical fabrication. The subsidence of the sphere and a more general condition with fewer symmetries and complex deformation of eccentricity, subsidence, and offset are first modeled in this paper, which could tune the mechanical frequency in a much wider spectral range than the pillar-diameter-induced perturbation. we also show that the mechanical quality factors for the non-whispering-gallery mechanical mode could be increased in the order of 4 magnitudes at a specific subsidence, and form a mechanical bound state in the continuum (BIC) which is induced by the symmetry breaking and reveals new mechanisms to confine radiation. A much broader BIC window width with higher mechanical quality factor could be achieved, which is of great importance in both fundamental research and scientific applications.

5.
Aging Ment Health ; 20(6): 567-74, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25853449

RESUMO

OBJECTIVES: To assess the reliability and validity of the Chinese version of Aging Perceptions Questionnaire (C-APQ). METHOD: Participants aged 65 years and over were recruited from February 2012 to November 2012. The Aging Perceptions Questionnaire was translated into Chinese version professionally. Content validity was examined by a panel of seven experts; item reliabilities were assessed by test-retest; internal consistency was assessed by Cronbach's α coefficient; half of the sample (N = 379) was selected to explore factorial structure of the C-APQ by exploratory factor analysis (EFA) and another half of the sample (N = 379) was selected to confirm the findings from the EFA by confirmatory factor analysis (CFA). Statistical package SPSS version 18.0 and Amos 17.0 were used for the analysis. RESULTS: The Cronbach's α coefficient of the C-APQ was 0.884. The test-retest reliability was satisfactory, with all intraclass correlation coefficients greater than 0.4. The overall content validity index was greater than 0.99. Seven factors (timeline acute/chronic, timeline cyclical, emotional representations, control positive, control negative, consequences positive and consequences negative) were identified in EFA and confirmed in CFA. CONCLUSION: The C-APQ could be a reliable and a valid measure of the self-perceptions of aging in the elderly in China, which may help to improve the life quality and extend longevity of the elderly.


Assuntos
Envelhecimento/psicologia , Psicometria/instrumentação , Autoimagem , Inquéritos e Questionários/normas , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
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