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151.
D.A. Fogaça F.S. Navarra L.G. Ferreira Filho 《Communications in Nonlinear Science & Numerical Simulation》2013,18(2):221-235
The Kadomtsev–Petviashvili (KP) nonlinear wave equation is the three dimensional generalization of the Korteveg-de Vries (KdV) equation. We show how to obtain the cylindrical KP (cKP) and cartesian KP in relativistic fluid dynamics. The obtained KP equations describe the evolution of perturbations in the baryon density in a strongly interacting quark gluon plasma (sQGP) at zero temperature. We also show the analytical solitary wave solution of the KP equations in both cases. 相似文献
152.
Carla Marisa Brito Carvalho Marta Akemi FujitaTimothy John Brocksom Kleber Thiago de Oliveira 《Tetrahedron》2013
New β-fused uracil-porphyrin conjugates were synthesized by the tetramerization of uracil-pyrroles under acidic conditions. Two different synthetic approaches were systematically studied in order to evaluate their efficiency, as well as the possibility to obtain a single regioisomer. Metallation effects were studied for aggregation in solution, and preliminary photophysical experiments were also performed in order to evaluate the potential of these new compounds. 相似文献
153.
Dr. Teng Zhang Dr. Yuichi Kitagawa Ryoma Moriake Pedro Paulo Ferreira da Rosa Dr. Md. Jahidul Islam Dr. Tomoki Yoneda Prof. Yasuhide Inokuma Dr. Koji Fushimi Prof. Yasuchika Hasegawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14438-14443
In this study, we have demonstrated a two-legged, upright molecular design method for monochromatic and bright red luminescent LnIII-silica nanomaterials. A novel EuIII-silica hybrid nanoparticle was developed by using a doubly binding TPPO−Si(OEt)3 (TPPO: triphenyl phosphine oxide) linker. The TPPO−Si(OEt)3 was confirmed by 1H, 31P, 29Si NMR spectroscopy and single-crystal X-ray analysis. Luminescent Eu(hfa)3 and Eu(tfc)3 moieties (hfa: hexafluoroacetylacetonate, tfc: 3-(trifluoromethylhydroxymethylene)camphorate) were fixed onto TPPO−Si(OEt)3-modified silica nanoparticles, producing Eu(hfa)3(TPPO−Si)2-SiO2 and Eu(tfc)3(TPPO−Si)2-SiO2, respectively. Eu(hfa)3(TPPO−Si)2−SiO2 exhibited the higher intrinsic luminescence quantum yield (93 %) and longer emission lifetime (0.98 ms), which is much larger than those of previously reported EuIII-based hybrid materials. Eu(tfc)3(TPPO−Si)2−SiO2 showed an extra-large intrinsic emission quantum yield (54 %), although the emission quantum yield for the precursor Eu(tfc)3(TPPO−Si(OEt)3)2 was found to be 39 %. These results confirmed that the TPPO−Si(OEt)3 linker is a promising candidate for development of EuIII-based luminescent materials. 相似文献
154.
As part of an ongoing program directed toward the preparation of antraciclinones1 and aryl substituted lapachones2, which are important anticancer and antibiotic3 agents, we became interested in a efficient synthesis of substituted 1,4-naphthoquinones, such as juglone (3). This compound has received some attention due its activity as an allelophatic compound4. An extensive analysis of the literature procedures indicated that several methods are available starting from 1,5-dihydroxynaphthalene (1). All the procedures explored the oxidation of carbon four of the naphthyl ring by several known reagents, such as, chromium trioxide-piridine5, thallium trinitrate5, chromic acid6, peracetic acid7, dichromate8, iron (III) chloride9 and mercuric oxide10. None of the several known methods for the preparation of (3) proceeded in satisfactory yield (except for the thallium trinitrate method which gave 642 yield) and most of them gave a mixture of 1,2 and 1,4-naphthoquinone. 相似文献
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Malva sylvestris L. extract suppresses desferrioxamine‐induced PGE2 and PGD2 release in differentiated U937 cells: the development and validation of an LC‐MS/MS method for prostaglandin quantification 下载免费PDF全文
Cleverson Antonio Ferreira Martins Almeriane Maria Weffort‐Santos João Cleverson Gasparetto Angela Cristina Leal Badaró Trindade Michel Fleith Otuki Roberto Pontarolo 《Biomedical chromatography : BMC》2014,28(7):986-993
Malva sylvestris is a species used worldwide as an alternative to anti‐inflammatory therapies; however, its mechanism of action remains unknown. In this paper, the anti‐inflammatory effects of M. sylvestris alcoholic extracts were evaluated by measuring the pro‐inflammatory mediators PGE2 and PGD2 in desferrioxamine‐stimulated phorbol 12‐myristate 13‐acetate‐differentiated U937 cells. An HPLC‐DAD fingerprint of the M. sylvestris extract was performed and caffeic acid, ferulic acid and scopoletin were identified and quantified. An HPLC‐MS/MS method was developed and validated to separate and measure the prostaglandins. The lower limits of detection (~0.5 ng/mL for PGE2 and PGD2) and quantification (1.0 ng/mL for PGE2 and PGD2) indicated that the method is highly sensitive. The calibration curves showed excellent coefficients of correlation (r > 0.99) over the range of 1.0–500.0 ng/mL, and at different levels, the accuracy ranged from 96.4 to 106.4% with an RSD < 10.0% for the precision study. This method was successfully applied using U937‐d cells. A significant dose‐dependent reduction of PGE2 and PGD2 levels occurred using 10 µg/mL (10.74 ± 2.86 and 9.60 ± 6.89%) and 50 µg/mL of extract (48.37 ± 3.24 and 53.06 ± 6.15%), suggesting that the anti‐inflammatory mechanisms evoked by M. sylvestris may be related to modulation of these mediators. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
159.
Fila Karolina Grochowicz Marta Podkościelna Beata 《Journal of Thermal Analysis and Calorimetry》2018,133(1):489-497
Journal of Thermal Analysis and Calorimetry - The paper presents the synthesis, structure and polymerization of S-phenyl 2-methylprop-2-enethioate (PSM). This compound was prepared in the reaction... 相似文献