SPECTROSCOPY LETTERS
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2015
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IF 0.852
Bo Zhang,Yanbin Su,Lei Chen,Zhuofu Wu,Fengrong Zhang,Yanwen Su,Gang Zhao,Zhengqiang Li
The characteristic changes in UV-visible and Raman spectra of lithocholic acid on E-2-Butenal for antiglioma are the maximum absorption peak of E-2-Butenal from 302 to 319 nm, the decreases of Raman signal of 1688 cm−1 and 1641 cm−1 in E-2-Butenal by lithocholic acid with the phenomenon of 1688 cm−1 splitting, and the disappearance of the band at 932 cm−1, which clearly displays the change of wagging in methyl. In the presence of mitochondrial protein deriving from glioma, the above mentioned effects of lithocholic acid on E-2-Butenal are more significant by Raman spectra detections. The molecular targets of lithocholic acid on E-2-Butenal are carbonyl group, conjugated double bonds, and methyl, respectively. The study concludes that the interaction between lithocholic acid and E-2-Butenal decreases the carbonyl group bond strength in E-2-Butenal and then changes the structure and function of E-2-Butenal. The internal cause of the interaction between lithocholic acid and E-2-Butenal leading to the change of the carbonyl group bond strength is the electronic delocalization near the carbonyl group bond in E-2-Butenal. Since E-2-Butenal derives from glioma in the process of lipid peroxidation of mitochondria, our investigation significantly contributes to understanding the mechanism of action of lithocholic acid as a potential antiglioma drug.
研究领域:
生物化学
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药物学
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肿瘤学
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2019
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IF 7.723
Haiqiang Lin,Hongyan Qu,Weikun Chen,Kang Xu,Jianwei Zheng,Xinping Duan,Hesheng Zhai,Youzhu Yuan
In gas-phase chemoselective hydrogenation of crotonaldehyde on Ag-based catalysts, zirconia doping on silica supports was found to improve catalytic performance in terms of unsaturated alcohol selectivity, hydrogenation activity, and stability. The surface modification of silica by zirconia doping favors the fine dispersion of Ag species due to the enhanced quantity and strength of surface acid sites, which enable construction of abundant catalytic sites effective for C O bond hydrogenation. High crotyl alcohol selectivity, exceeding 80%, and significant inhibition of monohydrogenation on the C C bond were observed on the optimal Ag/Zr–SiO 2 catalyst. Dynamic O 2 chemisorption measurement revealed that the pure Ag powders did not chemisorb O 2 irreversibly under 323 K, but SiO 2 or Zr–SiO 2 supported Ag catalysts did. The amounts of Ag active for O 2 chemisorption, which are at least one order of magnitude lower than that of surface Ag derived from TEM and XRD characterizations, match well with the perimeter interface Ag of hemispherical particles. A strong correlation between hydrogenation activity and O 2 uptake on those Ag/SiO 2 and Ag/Zr–SiO 2 catalysts with different Ag dispersions and deactivation degrees was observed, implying that the effective catalytic sites for crotonaldehyde chemoselective hydrogenation may originate from accessible interface sites with unique redox properties. Catalyst induction and deactivation were observed on both Ag/SiO 2 and Ag/Zr–SiO 2 catalysts in real catalytic operation. Changes in metal stable interface structure, rather than metal aggregation and coagulation, are assumed to be the main cause of irreversible catalyst deactivation, because the apparent Ag particle sizes changed slightly, but the oxygen chemisorption ability deteriorated considerably. Electropositive Ag sites interacting with neighboring oxygen from oxide supports at the ternary Ag–ZrO 2 –SiO 2 interface are proposed to account for highly selective C O bond hydrogenation to produce the desired unsaturated alcohol.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2021
·Vol. 132
·期 1
·301-315
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IF 2.081
Hu Yi-Ming,Zheng Wan-Bin,Jia Ai-Ping,Luo Meng-Fei,Tang Cen,Lu Ji-Qing
A series of Ir/BN catalysts with same Ir contents (2 wt%) were calcined at different temperatures and tested for gas phase selective hydrogenation of crotonaldehyde. It was found that the thermal treatment exerted significant impacts on the structural and electronic properties of the 2Ir/BN catalysts. The catalyst calcined at 500 °C (2Ir/BN-5) showed the best performance, with a steady state of conversion of ca. 21% and a crotyl alcohol selectivity of ca. 83% at reaction temperature of 80 °C. Kinetic analysis indicated that the enhanced activity on the 2Ir/BN-5 catalyst was related to its higher surface coverage of crotonaldehyde because of the presence of small Ir particles (with a mean diameter of 3.4 nm) compared to those in the catalyst calcined at 600 °C (2Ir/BN-6, with a mean diameter of 4.4 nm). Also, the surface of the Ir species in the 2Ir/BN-5 catalyst are more electron-enriched compared to that in the 2Ir/BN-6, which suppressed the adsorption of C=C bond and thus improves the selectivity to CROL.
研究领域:
催化
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化学工程
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物理化学
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产品关联
DOI
高影响因子
Food Chemistry-X
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2024
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IF 6.5
Yujiao Cheng,Leng Han,Linzi Shao,Hua Wang,Zheng Guo,Guijie Li
Pomelo flowers emit a strong fragrance and give aromatic odors. Volatile compounds from pomelo flowers were analyzed at three developmental stages and in the main organs by molecular sensory science. A total of 134 volatiles including 25 odorants, were analyzed by gas chromatography–mass spectrometry/pulsed flame photometric detector (GC–MS/PFPD) and multidimensional GC–MS/olfactory (MDGC–MS/O). The total volatile content varied among pomelo flowers at different developmental stages (stage-III > stage-II > stage-I) and among different organs of pomelo flowers (petal > pistil > stamen). Linalool was an important odorant with a high OAV, and floral/fruity comprised the predominant aroma profile. Four odorants, ethyl 2-methylbutanoate, linalool, β-myrcene, and 2-butenal, were selected based on variable importance in projection (VIP) values and contributed mainly to the discrimination of pomelo flowers at three different developmental stages. Linalool, β-myrcene, d -limonene, and ethyl hexanoate were potential markers for evaluating flavor differences in pomelo floral organs.
研究领域:
食品科学
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农业化学
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植物生理学
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分析化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）