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61.
Qin Li Zihan Chen Jianrong Zhang Qiuying Yan Li Liu Dongxin Tang Liu Li Jinge Zhang Cheng Hu Jiayi Ma Haibo Cheng An Kang Dongdong Sun 《Journal of separation science》2023,46(14):2300094
Coptis chinensis Franch. and Sophora flavescens Ait. is a herbal pair frequently used in treating ulcerative colitis. However, the bio-disposition profile of the major components in the inflamed gut remains unclear, which is essential to understand the pharmacological material basis of this herb pair. Here we established an integral quantitative and chemometric method to deduce the colonic metabolism differences of this herbal pair in normal and colitis mice. With this LC-MS method, a total of 41 components have been found in the Coptis chinensis Franch. and Sophora flavescens Ait. extract, and 28 metabolites were found in the colon after oral administration. Alkaloid and its phase I metabolites were the main components in the colon of normal and colitis mice. The results of principal component analysis at 6 h after oral administration showed significant colonic metabolism differences between normal and colitis mice. Heamap results showed that colitis induced significant changes in the colonic bio-disposition of this herbal pair extract. In particular, in the context of colitis, the phase I metabolism of berberine, coptisine, jatrorrhizine, palmatine,and epiberberine has been inhibited. These results may provide a basis for understanding the pharmacological material basis of Coptis chinensis Franch. and Sophora flavescens Ait. in treating ulcerative colitis. 相似文献
62.
Shourui Li Shouchao Liu Zhiwei Fu Qiuying Li Chifei Wu Weihong Guo 《Surface and interface analysis : SIA》2017,49(3):197-204
Carbon black (CB) was encapsulated by the sodium lignosulphonate via the strong π–π* interaction force of aromatic ring in the planetary ball milling instrument. The use of new surfactant and ball milling instrument met the requirements about the low‐cost standard and provided an important sense to industrialization in comparison with the old surfactant, the poly(sodium 4‐styrenesulfonate). The successful encapsulation was confirmed by Raman spectroscopy, X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermal gravimetric analysis. Encapsulation ratio of the modified CB increased to 15.9% when CB was prepared at longer milling time and with agate balls in different size. The morphology and dispersibility of samples studied by transmission electron microscope, sedimentation experiment and ultraviolet–visible spectroscopy showed that the modified CB dispersed stably in the deionized water. The average diameter and absolute value of zeta potential of the modified CB decreased and increased compared with those of CB, respectively, which confirmed further that sodium lignosulphonate encapsulated on the surface of CB make CB disperse better. In addition, the average diameter and zeta potential of the samples were affected by ball milling conditions. The modified CB prepared at longer milling time and with different sizes of agate balls had better dispersibility than the ones prepared at shorter milling time and with same size of agate balls. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
63.
Chiral Carbonaceous Nanotubes Modified with Titania Nanocrystals: Plasmon‐Free and Recyclable SERS Sensitivity 下载免费PDF全文
Dr. Bocheng Qiu Dr. Mingyang Xing Qiuying Yi Prof. Dr. Jinlong Zhang 《Angewandte Chemie (International ed. in English)》2015,54(36):10643-10647
Chiral carbonaceous nanotubes (CNT) were successfully used in plasmon‐free surface‐enhanced Raman scattering (SERS) for the first time. Further modification of TiO2 nanocrystals on the chiral CNTs successfully realized the recycling of SERS substrate as chiral CNT/TiO2 hybrids. The high SERS sensitivity of methylene blue (MB) over the chiral CNT/TiO2 hybrids is ascribed to the laser‐driven birefringence induced by the helical structure, which provides much more opportunities for the occurrence of Raman scattering. The TiO2 nanocrystals highly dispersed on the surface and inside the hollow cavity of chiral CNTs can completely degrade the MB under the solar light irradiation, leading to the self‐cleaning of SERS substrate. The present research opens a new way for the application of chiral inorganic materials in plasmon‐free SERS detection. 相似文献
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ASYMPTOTIC BEHAVIOR FOR GENERALIZED GINZBURG-LANDAU POPULATION EQUATION WITH STOCHASTIC PERTURBATION 下载免费PDF全文
In this paper, we are devoted to the asymptotic behavior for a nonlinear parabolic type equation of higher order with additive white noise. We focus on the Ginzburg-Landau population equation perturbed with additive noise. Firstly, we show that the stochastic Ginzburg-Landau equation with additive noise can be recast as a random dynamical
system. And then, it is proved that under some growth conditions on the nonlinear term, this stochastic equation has a compact random attractor, which has a finite Hausdorff dimension. 相似文献
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68.
建立了激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)法测定纯钌中Mg、Al、Fe、Ni、Cu、Zn、Rb、Rh、Pd、Mo、Ag、Cd、Sn、Ba、Ir、Pt、Au、Pb和Si等19种杂质元素的分析方法。优化了仪器参数,给出了激光能量为60%,剥蚀孔径为110μm,扫描速率为50μm/s,脉冲频率为10 Hz,载气流量为0.74 L/min条件下,信号强度和稳定性最佳。由于钌标准样品难以获得,因此选择用纯钌粉样品,高温高压溶解后,采用ICP-MS法定值所测元素(除硅外)。根据钌粉样品的ICP-MS法定值结果确定了测定元素的相对灵敏度因子(RSF),采用相对灵敏度因子(RSF)对所测结果进行校正,方法准确、快速,检出限为0.007~12.8μg/g,相对标准偏差(RSD)为10%~30%。测定纯钌中杂质元素,结果与ICP-MS法测定的结果吻合。 相似文献
69.
In this paper, three luminescent metal–organic frameworks, namely: [Zn(p-IPhHIDC)]n (1), {[Cd(p-IPhIDC)(H2O)]·CH3OH}n (2) and [Zn(p-TIPhHIDC)]n (3), bearing two novel substituted imidazole dicarboxylate ligands, 2-(p-N-imidazol-1-yl)-phenyl-1H-imidazole-4,5dicarboxylic acid (p-IPhH3IDC) and 2-p-(1H-1,2,4-triazol-1-yl)-phenyl-1H-imidazole-4,5dicarboxylic acid (p-TIPhH3IDC), have been prepared and characterised through infrared spectra, X-ray powder diffraction, elemental analyses, thermogravimetric analyses and single-crystal X-ray diffraction. Ignoring the free methanol molecule and coordinated water in 2, 1–3 are similar structures. Moreover, the luminescent properties of the MOFs have been explored. It was found that MOFs 1 and 2 show good luminescent sensing of Fe3+ in varying degrees, and 3 of K+. 相似文献
70.
Zhizhong Su Yongjun Liu Weihong Guo Qiuying Li Chifei Wu 《Journal of Macromolecular Science: Physics》2013,52(4):670-683
A novel method was employed to modify the surface of carbon black (CB) by an organic small molecule in a Haake Rheomix mixer. The modified carbon black (MCB) was dispersed uniformly in poly(lactic acid; PLA). The crystallization behaviors of PLA, PLA/CB and PLA/MCB composites were investigated by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS) and polarizing optical microscopy. It is found that the addition of CB or MCB can influence the crystallization behavior of PLA. PLA/MCB has a faster crystallization rate and higher crystallization peak temperature than PLA/CB. For non-isothermal studies, Jeziorny and Mo equations were employed. The Mo equation can well describe the non-isothermal crystallization of the three samples. For PLA/CB and PLA/MCB composites containing 3wt% fillers, the nucleating activity for CB is about 0.32, and about 0.16 for MCB. All these results show that MCB is an effective nucleating agent. PLA/MCB has a higher nucleation rate than PLA/CB because of the finer dispersed particles size and improved interaction between MCB and PLA. 相似文献