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141.
Shi-Ji Xiao Xin-Xiang Lei Bing Xia Dan-Qing Xu Hong-Ping Xiao Hong-Xi Xu Fang Chen Li-Sheng Ding Yan Zhou 《Tetrahedron letters》2014
Two novel lignans, gymnothespirolignans A (1) and B (2), possessing a rare polycyclic spiro skeleton, were isolated from the endemic plant of Gymnotheca involucrata Pei. Their structures were determined by spectroscopic evidences and the absolute configurations were confirmed by single crystal X-ray diffraction analysis. Compounds 1 and 2 showed promising antiviral activities against RSV with an IC50 value of 31.87 and 17.51 μM, respectively. 相似文献
142.
Zhiwei Men Wenhui Fang Shenghan Wang Zhanlong Li Chenglin Sun Xiaojun Wang 《Journal of Raman spectroscopy : JRS》2015,46(4):388-391
The polarized Raman spectra of the upper part of a thin ice Ih film were obtained in the range of 150 cm−1 to 3800 cm−1. The spectra showed clear polarization dependence; several new peaks were also observed. The longitudinaloptic–tranverseoptic (LO–TO) splitting of the mode near 220 cm−1 in the translational vibration region was experimentally confirmed at 133 K. The Fermi resonance between the bending overtone (around 3270 cm−1) and symmetry stretching fundamental (around 3350 cm−1) in the stretching vibration region appeared at nearly the same temperature. Results showed that ice XI (i.e. proton‐ordered phase of ice Ih) slowly formed in the upper part of a thin ice Ih film without KOH as the temperature gradually decreased below 133 K. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
143.
Juanzi Shi HongXia Shen Lisheng Zhang Peijie Wang Yan Fang Guozhen Wu 《Journal of Raman spectroscopy : JRS》2015,46(12):1303-1309
An algorithm is employed to retrieve the differential bond polarizabilities (DBP) of the C‐C bonds from the Raman optical activity spectrum of (‐)β‐pinene. (‐)β‐pinene possesses two stereo centers (chiral centers) and a local mirror reflection that interchanges the S type part and R type part in one molecular. It is demonstrated that this local mirror reflection could induce an approximate (or symmetry breaking) mirror reflection that reverses the signs of the DBP of the pair bond coordinates that are related to each other by the mirror reflection.This can be called intramolecular enantiomerism (IE). More cases of IE are discussed by the analysis of (‐)α‐pinene, (R)‐(+)‐4‐isopropyl‐1‐methylcyclohexene and (R)‐(+)‐3‐methylcyclohexanone together with previously studied limonene case. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
144.
Li Yang Fu Xuan Li Xu-Xin Zhang Fang Wu Qiang Wang Yun Yan Ze-Yi 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):877-888
Journal of Radioanalytical and Nuclear Chemistry - In this study, the imidazole-based poly(ionic liquid)s (PILs) synthesized by one step method has been applied for the enrichment and recovery of... 相似文献
145.
Li Tingting Wang Fang Xia Liangshu 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2655-2665
Journal of Radioanalytical and Nuclear Chemistry - Uranium, as a highly toxic radioactive contaminant existing in mine wastewater and contaminated groundwater, has sparked widespread alarm in... 相似文献
146.
Fang Sheng Bangyan Hu Qiang Jin Jiangbo Wang Cuiyun Wu Zhengrong Luo 《Molecules (Basel, Switzerland)》2021,26(10)
Husk and pellicle as the agri-food waste in the walnut-product industry are in soaring demand because of their rich polyphenol content. This study investigated the differential compounds related to walnut polyphenol between husk and pellicle during fruit development stage. By using ultra-high performance liquid chromatography-quadrupole-orbitrap (UHPLC-Q-Orbitrap), a total of 110 bioactive components, including hydrolysable tannins, flavonoids, phenolic acids and quinones, were tentatively identified, 33 of which were different between husk and pellicle. The trend of dynamic content of 16 polyphenols was clarified during walnut development stage by high-performance liquid chromatography (HPLC). This is the first time to comprehensive identification of phenolic compounds in walnut husk and pellicle, and our results indicated that the pellicle is a rich resource of polyphenols. The dynamic trend of some polyphenols was consistent with total phenols. The comprehensive characterization of walnut polyphenol and quantification of main phenolic compounds will be beneficial for understanding the potential application value of walnut and for exploiting its metabolism pathway. 相似文献
147.
148.
正Dear Editors,Active Galactic Nuclei(AGNs)are very effective tools to study the environment both intrinsic to the central black holes of galaxies[1],or absorbing gas distributed along the sight lines.Recently,numerous highly ionized,local(z=0)metal absorption lines were detected in the X-ray spectra of background AGNs[2],providing an important method in probing hot gas and its content in and around our Galaxy.Of particular 相似文献
149.
In situ synthesis of CdS/ZnS composite nanoparticles from ZIF-8 for visible light disposal of Cr(VI)
Bai Lei Ge Lili Gu Junjiu Fang Lu Li Shaojun 《Journal of Sol-Gel Science and Technology》2021,99(1):211-219
Journal of Sol-Gel Science and Technology - Zeolitic Imidazolate Framework (ZIF-8) micropolyhedra were employed as a raw material for the synthesis of fine cadmium sulfide/zinc sulfide (CdS/ZnS)... 相似文献
150.