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排序方式: 共有152条查询结果,搜索用时 15 毫秒
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Na Xu Xu Dong Xu Li Yan Ma Jing Quan Yuan Jian Hua Miao Yan Cheng Jun Shan Yang 《中国化学快报》2010,21(6):696-698
<正>A new homoflavonoid was isolated from the seed of Caesalpinia minax Hance.On the basis of spectral evidences,its structure was established and named as minaxin. 相似文献
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Linuan Yin Ying Li Jun Wang Yu Zhai Yumei Kong Jingqun Gao Guangxi Han Ping Fan 《Journal of luminescence》2012,132(11):3010-3018
In this progress report, seven kinds of novel carefully designed and fabricated up-conversion luminescence agents, Er3+:Y3Al5O12, Er3+:YbnY3?nAl5O12, Er3+:Y3BaAl5?aO12, Er3+:Y3GabAl5?bO12, Er3+:Y3Al5NxO12?x, Er3+:Y3Al5FyO12?y and Er3+:YbnY3?nBaGabAl5?a?bNxFyO12?x?y, are successfully synthesized using sol–gel methods. After that, their corresponding photocatalysts, Er3+:Y3Al5O12/TiO2, Er3+:YbnY3?nAl5O12/TiO2, Er3+:Y3BaAl5?aO12/TiO2, Er3+:Y3GabAl5?bO12/TiO2, Er3+:Y3Al5NxO12?x/TiO2, Er3+:Y3Al5FyO12?y/TiO2 and Er3+:YbnY3?nBaGabAl5?a?bNxFyO12?x?y/TiO2, are also prepared by sol–gel coating process. The obtained up-conversion luminescence agents and photocatalysts were characterized by using XRD, XPS, SEM, UV–vis and fluorescence spectrophotometer. Synchronously, several kinds of organic dyes are used to test their photocatalytic degradation using prepared photocatalysts. It indicates that the up-conversion luminescence ability of Er3+:Y3Al5O12 can be improved obviously through doping of some elements. And then, the photocatalytic activity of TiO2 is markedly enhanced by modified up-conversion luminescence agents which can transform much visible light into ultraviolet light. 相似文献
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YIN Zheng & ZENG MingHua Key Laboratory for Chemistry Molecular Engineering of Medicinal Resources Ministry of Education School of Chemistry & Chemical Engineering Guangxi Normal University Guilin China 《中国科学B辑(英文版)》2011,(9)
Recently,research of crystalline-state transformation involving the removal/inclusion of guest molecules in porous coordination polymers(PCPs) was underway.Crystalline-state transformation,especially,single-crystal to single-crystal(SC-SC) transformation as new method for the direct observation of host-guest chemistry,can reveal the intrinsic relevance and interaction between the framework and guest molecules.This review describes our work concerning PCPs and recent investigations of others,within the last ... 相似文献
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Min Sun Yan Gao Chenyu Guo Fengliang Cao Zhimei Song Yanwei Xi Aihua Yu Aiguo Li Guangxi Zhai 《Journal of nanoparticle research》2010,12(8):3111-3122
Curcumin, a widely used coloring agent and spice in food, has a potential in blocking brain tumor formation and curing Alzheimer’s disease. Due to the specific properties of blood–brain barrier (BBB), only traces of curcumin were transported across BBB. The aim of the present study was to design and characterize curcumin loaded polybutylcyanoacrylate nanoparticles (PBCN) coated with polysorbate 80, and to evaluate the effect of PBCN as a delivery system on carrying curcumin across BBB. Curcumin loaded nanoparticles were prepared by an anionic polymerization method, and they presented in a core–shell spherical shape under transmission electron microscopy, with an average diameter of 152.0 nm. The average drug loading was 21.1%. Physicochemical status of curcumin in the nanoparticles was confirmed with differential scanning colorimetry and Fourier transform infrared spectroscopy. The in vitro release behavior of drug from the nanoparticles was fitted to a double phase kinetics model. The studies of pharmacokinetic and bio-distribution to brain were conducted in mice after intravenous administration of the nanoparticle formulation at the dose of 5 mg/kg and curcumin solution at the dose of 10 mg/kg via the tail vein. The results showed that in plasma, the area under concentration–time curve (AUC0–∞) for curcumin loaded nanoparticles was greater than that for the control solution, moreover, the mean residence time of curcumin loaded nanoparticles was 14-fold that of the control solution. In brain, AUC0–∞ for curcumin loaded nanoparticles was 2.53-fold that for the control solution. In conclusion, the present study demonstrated that PBCN could enhance the transport of curcumin to brain and have a potential as a delivery system to cross the BBB. 相似文献
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Jun Wang Yanhui Lv Liqun Zhang Bin Liu Renzheng Jiang Guangxi Han Rui Xu Xiangdong Zhang 《Ultrasonics sonochemistry》2010,17(4):642-648
The CeO2/TiO2, SnO2/TiO2 and ZrO2/TiO2 composites were prepared by dispersing various nano-sized oxides (CeO2, SnO2, ZrO2 and TiO2) with ultrasound and mixing TiO2 with CeO2, SnO2 and ZrO2, respectively, in boiling water in a molar ratio of 4:1, followed by calcining temperature 500 °C for 60 min. Then a series of sonocatalytic degradation experiments were carried out under ultrasonic irradiation in the presence of CeO2/TiO2, SnO2/TiO2 and ZrO2/TiO2 composites and nano-sized TiO2 powder. Also, the influences of heat-treatment temperature and heat-treatment time on the sonocatalytic activities of CeO2/TiO2, SnO2/TiO2 and ZrO2/TiO2 composites, and of irradiation time and solution acidity on the sonocatalytic degradation of Acid Red B were investigated by UV–vis spectra. It was found that the sonocatalytic degradation of Acid Red B shows significant variation in rate and ratio that decreases in order: CeO2/TiO2 > SnO2/TiO2 > TiO2 > ZrO2/TiO2 > SnO2 > CeO2 > ZrO2, and the corresponding ratios of Acid Red B in aqueous solution are 91.32%, 67.41%, 65.26%, 41.67%, 28.34%, 26.75% and 23.33%, respectively. And that the degradation ratio is only 16.67% under onefold ultrasonic irradiation. Because of the good degradation efficiency, this method may be an advisable choice for the treatment of non- or low-transparent wastewaters in the future. 相似文献
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