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871.
Andreas Mautner Xiaohua Qin Harald Wutzel Samuel C. Ligon Barbara Kapeller Doris Moser Guenter Russmueller Juergen Stampfl Robert Liska 《Journal of polymer science. Part A, Polymer chemistry》2013,51(1):203-212
Monomers for radical photopolymerization based on vinyl esters (VEs) have recently been identified as suitable alternatives to (meth)acrylates on account of their low irritancy and cytotoxicity. The drawback of most VEs with abstractable hydrogens is their relatively low reactivity compared with (meth)acrylates. Within this article, we proved by photo‐differential scanning calorimetry measurements and real‐time Fourier transform infrared spectroscopy that the thiol‐ene concept is able to improve the photoreactivity of these VEs to a large extent to a level between those of acrylates and methacrylates. Other VEs have now a reactivity of at least the level of similar acrylates. Mechanical properties as determined by Dynamic Mechanical Analysis and Charpy impact tests showed significant toughening of these materials. Furthermore, we were able to confirm low toxicity of all components by osteoblast cell culture experiments. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
872.
Muthiah Manoharan Akin Akinc Rajendra K. Pandey June Qin Philipp Hadwiger Matthias John Kathy Mills Klaus Charisse Martin A. Maier Lubomir Nechev Emily M. Greene Pradeep S. Pallan Eriks Rozners Kallanthottathil G. Rajeev Martin Egli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2011,123(10):2332-2336
873.
Biomimetic Surface Engineering of Lanthanide‐Doped Upconversion Nanoparticles as Versatile Bioprobes
874.
875.
Yue‐Hu Wang Qian‐Yun Sun Fu‐Mei Yang Chun‐Lin Long Fu‐Wei Zhao Gui‐Hua Tang Hong‐Mei Niu Huan Wang Qiao‐Qin Huang Jin‐Jin Xu Li‐Juan Ma 《Helvetica chimica acta》2010,93(12):2467-2477
Ten new phenolic compounds including the six neolignans 1 – 3 and 6 – 8 and four caffeoyl derivatives, i.e., myo‐inositol 1‐caffeate ( 9 ), myo‐inositol 6‐caffeate ( 10 ), myo‐inositol 5‐caffeate ( 11 ), and paucine 3′‐β‐D ‐glucopyranoside ( 12 ) were isolated from the whole plants of Selaginella moellendorffii (caffeic acid=3‐(3,4‐dihydroxyphenyl)prop‐2‐enoic acid). Their structures were established by spectroscopic and chemical methods. 相似文献
876.
Chiral C2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 5a–c and the chiral C2-symmetric NHC-palladium complexes 5d and 5e prepared from (R)-BINAM or H8-(R)-BINAM could be used as the catalysts for the enantioselective arylation of arylaldehydes with arylboronic acids in which NHC-Pd complex 5a was found to be fairly effective in this reaction to give the corresponding adducts in moderate enantioselectivities along with moderate to good yields. 相似文献
877.
878.
Xuesong Shen Meihua Jin Chunxia Zhao Xinqiang Tan Hanfu Liu Xuelian Qin Zhuangpingi Qiu Yi Liu 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1947-1952
In this study, the metabolic thermogenic curves of mitochondria isolated from rat liver tissue were drawn, and the effects of artesunate on metabolic activity of mitochondria were studied using TAM Air Isothermal Microcalorimeter. After isolation from the rat liver, mitochondria still have metabolic activity and can live for a week with appropriate nutrients. With the addition of artesunate (7.5 μM/mL), the metabolic activity of mitochondria was completely lost at this concentration. From the thermogenic curves, we obtained the thermokinetic equations under different conditions: T max = 2512.24 + 1761.53c, R = 0.9375; and Tlag (min) = 707.26 + 285.17c, R = 0.9846. The results showed that artesunate was a mitochondria-targeted drug having obvious effects on mitochondrial metabolism. 相似文献
879.
Zuliang Luo Weijun Kong Feng Qiu Meihua Yang Qian Li Riwei Wei Xiaoli Yang Jieping Qin 《Journal of separation science》2013,36(4):699-705
A simple and sensitive HPLC coupled with photodiode array (HPLC–PDA) method was developed for simultaneous determination of seven lignans in Justicia procumbens using relative response factors (RRFs). The chromatographic separation was performed on a Shiseido Capcell Pak C18 column (250 × 4.6 mm id, 5 μm), a gradient elution of acetonitrile/water, and a photodiode array detector. The column temperature was maintained at 35°C and the detection wavelength was set at 256 nm. Chinensinaphthol methyl ether was selected as the reference compound for calculating the relative response factors of the lignans. It has shown that the RRFs for lignans are quite similar at 256 nm of detection under different analytical conditions (different columns and HPLC instruments). Using RRFs, not every lignan is needed as a reference standard, making the method ideal for rapid, routine analysis, especially for those laboratories where lignans standards are not readily available. An economic and practicable HPLC method using RRFs was established for the determination of seven lignans in J. procumbens. This method not only can determine multiple indexes in traditional Chinese medicines (TCMs) simultaneously, but also resolve the problem of lacking of chemical standards. It will be a good quality evaluation method and pattern for TCMs. 相似文献
880.
Dr. Chun‐Yi Sun Prof. Xin‐Long Wang Chao Qin Jun‐Ling Jin Zhong‐Min Su Peng Huang Kui‐Zhan Shao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(11):3639-3645
Two anionic metal–organic frameworks (MOFs) with 1D mesoporous tubes ( 1 ) and chiral mesoporous cages ( 2 ) have been rationally constructed by means of a predesigned size‐extended hexatopic ligand, namely, 5,5′,5′′‐(1,3,5‐triazine‐2,4,6‐triyl)tris‐ (azanediyl)triisophthalate (TATAT). Charge neutrality is achieved by protonated dimethylamine cations. Notably, the two MOFs can be used to separate large molecules based on ionic selectivity rather than the size‐exclusion effect so far reported in the literature. Owing to the imino triazine backbone and carboxyl groups of the hexatopic ligand, which provide important host–guest interactions, rare solvatochromic phenomena of 1 and 2 are observed on incorporating acetone and ethanol guests. Furthermore, guest‐dependent luminescence properties of compound 2 were investigated, and the results show that luminescence intensity is significantly enhanced in toluene and benzene, while quenching effects are observed in acetone and ethanol. Thus, compound 2 may be a potential material for luminescent probes. 相似文献