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251.
Frontispiece: EPR Studies of the Binding Properties,Guest Dynamics,and Inner‐Space Dimensions of a Water‐Soluble Resorcinarene Capsule 下载免费PDF全文
252.
Karim Aissou Muhammad Mumtaz
zlem Usluer Gilles Pcastaings Giuseppe Portale Guillaume Fleury Eric Cloutet Georges Hadziioannou 《Macromolecular rapid communications》2016,37(3):221-226
Well‐defined single‐ion diblock copolymers consisting of a Li‐ion conductive poly(styrenesulfonyllithium(trifluoromethylsulfonyl)imide) (PSLiTFSI) block associated with a glassy polystyrene (PS) block have been synthesized via reversible addition fragmentation chain transfer polymerization. Conductivity anisotropy ratio up to 1000 has been achieved from PS‐b‐PSLiTFSI thin films by comparing Li‐ion conductivities of out‐of‐plane (aligned) and in‐plane (antialigned) cylinder morphologies at 40 °C. Blending of PS‐b‐PSLiTFSI thin films with poly(ethylene oxide) homopolymer (hPEO) enables a substantial improvement of Li‐ion transport within aligned cylindrical domains, since hPEO, preferentially located in PSLiTFSI domains, is an excellent lithium‐solvating material. Results are also compared with unblended and blended PSLiTFSI homopolymer (hPSLiTFSI) homologues, which reveals that ionic conductivity is improved when thin films are nanostructured.
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In this paper, we determine the universal central extension, derivation algebra and automorphism group of the twisted N = 1 Schrödinger–Neveu–Schwarz algebra. Furthermore, we generalize these results to the generalized twisted N = 1 Schrödinger–Neveu–Schwarz algebra in the final section. 相似文献
255.
Epicatechin ( 3 ) and five oligomers ( 2 , 4 , 5 , 10 , 11 ) together with five other type compounds were isolated and characterized from n‐BuOH and EtOAc soluble fractions of the ethanol extract of the leaves of Machilus konishii Hayata. Their structures were elucidated by means of MS and NMR spectroscopic analyses. Dehydrodiepicatechin A ( 11 ) is the first occurrence as a natural product although it has been prepared from epicatechin. The stereochemistry of 11 is elucidated for the first time on the basis of 1D NOESY and chemical model analyses. Tiliroside ( 7 ) and kaempferol 3‐O‐α‐L‐(2″,4″‐di‐E‐p‐coumaroyl)‐rhamnopyranoside ( 8 ) showed moderate inhibitory activity against α‐glucosidase. 相似文献
256.
Wei‐Guang Shan Zai‐Lin Gao You‐Min Ying Jia‐Gui Xiang Fa‐Song Wang Zha‐Jun Zhan 《Helvetica chimica acta》2014,97(11):1526-1530
Two new tirucallane‐type triterpenoids, (24Z)‐tirucalla‐7,24‐diene‐3β,11β,26‐triol ( 1 ) and (3S,24R)‐tirucall‐7‐ene‐3,24,25‐triol ( 2 ), along with the known compound celastrol ( 3 ), were isolated from the root barks of Celastrus stylosus Wall . The structures of 1 – 3 were established by spectroscopic methods, including extensive 2D NMR and MS analyses. It is the first report on tirucallane‐type triterpenoids from the genus Celastrus and may be of vital chemotaxonomic significance. 相似文献
257.
Gregory Rix Louis-Martin Rousseau Gilles Pesant 《The Journal of the Operational Research Society》2015,66(2):278-287
We present a tactical wood flow model that appears in the context of the Canadian forestry industry, and describe the implementation of a decision support system created for use by an industrial partner. In this problem, mill demands and harvested volumes of a heterogeneous set of log types are given over a multi-period planning horizon. Wood can be stored at the forest roadside before delivery at a financial cost. Rather than solve this as a network linear programme on the basis of out-and-back deliveries, we choose to model this problem as a generalization of a log-truck scheduling problem. By routing and scheduling the trucks in the resolution, this allows us to both anticipate potential backhaul opportunities for cost and fuel savings, and also minimize queuing times at log-loaders, management of which is a major concern in the industry. We model this problem as a mixed integer linear programme and solve it via column generation. The methodology is tested on several case studies. 相似文献
258.
Scheen G Ziouche K Bougrioua Z Godts P Leclercq D Lasri T 《Langmuir : the ACS journal of surfaces and colloids》2011,27(10):6490-6495
Polyimide is of great interest in the field of MEMS and microtechnology. It is often used for its chemical, thermal, mechanical, and optical properties. In this paper, an original study is performed on controlled variation of polyimide film wettability. A two-step microtexturing method is developed to transform hydrophilic polyimide surfaces into a superhydrophobic surface with low magnitude of hysteresis (Δθ ≈ 0° and contact angle θ ≈ 158°). This method is based on the conception of a new kind of fakir surface with triangular cross-section micropillars, the use of a two-scale roughening, and a C(4)F(8) coating. We demonstrate that the absence of hysteresis is related to a combination of two scales of structuring and the pillar shape. The technology that has been developed results in the simultaneous fabrication of adjacent superhydrophobic and superhydrophilic small areas, which allows an effect of self-positioning of water droplets when deposited on such a checkerboard-like surface. 相似文献
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260.
The dibromination of alkenes and alkynes with bromosuccinimide and sodium bromide catalyzed by FeBr3 under mild conditions has been developed.The trans-dibromo compounds were exclusively obtained with excellent yields. 相似文献