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181.
Roqueline Rodrigues Silva de Miranda Grácia Divina de Fátima Silva Lucienir Pains Duarte Sidney Augusto Vieira Filho 《Helvetica chimica acta》2007,90(4):652-658
The triterpene ester (3β)‐olean‐18‐en‐3‐yl stearate ( 1 ), together with (3β)‐urs‐12‐en‐3‐yl stearate ( 2 ), and (3β)‐lup‐20(29)‐en‐3‐yl stearate ( 3 ) were isolated from leaves of Maytenus salicifolia Reissek (Celastraceae). The structure of 1 , a new compound, including its configuration, was established by 1H, 13C, and DEPT‐135 NMR data, including 2D experiments (HSQC, HMBC, COSY, and NOESY). The molecular mass (692 Da) was confirmed by gas chromatography coupled with mass spectrometry (CG/MS). 相似文献
182.
”Eau de graphene” from a KC8 graphite intercalation compound prepared by a simple mixing of graphite and molten potassium 下载免费PDF全文
George Bepete Ferdinand Hof Kai Huang Katerina Kampioti Eric Anglaret Carlos Drummond Alain Pénicaud 《固体物理学:研究快报》2016,10(12):895-899
We synthesized KC8 by simply mixing molten potassium and graphite at 180 °C under inert atmosphere. The KC8 shows typical shiny bronze color, Raman characteristics and XRD pattern of an efficiently intercalated stage 1 GIC, and is of sufficient quality to produce fully exfoliated graphenide solutions in tetrahydrofuran (THF) and subsequently single layer graphene in water as ”eau de graphene” (EdG). The evolution of absorption and Raman spectroscopic signatures of the EdG as a function of processing conditions give key indications on the number of layers of the graphene flakes dispersed in EdG. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
183.
《Comptes Rendus Chimie》2016,19(4):505-510
The present study aims to demonstrate the direct link between the microbial ecosystem of drinking water distribution systems and animal health in pig breeding. Based on a survey over 18 months, a treatment using essential oils proved to be efficient in increasing piglet health and zootechnical performance. Water pipe biofilms were monitored by laser scanning confocal microscopy, while zootechnical performance and health cost data were collected from professional organisations. In two representative monitored herds, it was observed that the drinking water distribution pipes, initially fouled by fungi, were replaced by a bacterial film while both veterinary costs and the total feed conversion ratio decreased. Essential oils may thus provide an efficient and sustainable alternative to the massive use of antibiotics for transforming an initial detrimental ecosystem to a positive biofilm. 相似文献
184.
《Comptes Rendus Mecanique》2017,345(3):177-183
In this paper, we are interested in the connection between some stochastic games, namely the tug-of-war games, and non-local PDEs on graphs. We consider a general formulation of tug-of-war games related to many continuous PDEs. Using the framework of partial difference equations, we transcribe this formulation on graph, and show that it encompasses several PDEs on graphs such as the ∞-Laplacian, the game p-Laplacian with and without gradient terms, and the eikonal equation. We then interpret these discrete games as non-local tug-of-war games. The proposed framework is illustrated with general interpolation problems on graphs. 相似文献
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187.
研究了电子辐照对 Zn O/K2 Si O3 型热控涂层光学性能的影响。采用 1 0 ,3 0 ,50和 70 ke V的电子对试样进行辐照。在辐照前后对每一个试样的光谱反射系数进行了原位测量。根据 Johnson太阳光谱分布计算了涂层的太阳光谱吸收系数。分析了电子能量对光谱反射系数和太阳光谱吸收系数的影响 ,并对红外区光谱反射系数的变化结果进行了讨论。实验结果发现电子辐照后 Zn O/K2 Si O3 涂层的光学性能发生严重退化 ,退化程度取决于电子能量 ,随电子能量的增大而增大。 相似文献
188.
Two novel Ni(II) complexes {[Ni(en)2(pot)2]0.5CHCl3} (3) {pot = 5-phenyl-1,3,4-oxadiazole-2-thione} (1) and [Ni(en)2](3-pytol)2 (4) {3-pytol = 5-(3-pyridyl)-1,3,4-oxadiazole-2-thiol} (2) have been synthesized using en as coligand. The metal complexes have been characterized by physical and analytical techniques and also by single crystal X-ray studies. The complexes 3 and 4 crystallize in monoclinic system with space group P21/a and P121/c, respectively. The complex 3 has a slightly distorted octahedral geometry with trans (pot)− ligands while 4 has a square planar geometry around the centrosymmetric Ni(II) center with ionically linked trans (3-pytol)− ligands. The π?π (face to face) interaction plays an important role along with hydrogen bondings to form supramolecular architecture in both complexes. 相似文献
189.
采用循环伏安法(CV)和差示脉冲伏安法(DPV)研究了配合物Co(en)33+与柠条叶DNA的相互作用.体系式电势E0'的负移和峰电流的下降表明,该配合物与柠条叶DNA有明显相互作用,小分子配合物与柠条DNA可能以非共价方式结合. 相似文献
190.