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排序方式: 共有347条查询结果,搜索用时 15 毫秒
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Daniel Depes Jin-Ho Lee Elizaveta Bobkova Lucie Jezkova Iva Falkova Felix Bestvater Eva Pagacova Olga Kopecna Mariia Zadneprianetc Alena Bacikova Elena Kulikova Elena Smirnova Tatiana Bulanova Alla Boreyko Evgeny Krasavin Michael Hausmann Martin Falk 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2018,72(9):158
203.
Three Lewis acid–base adducts t‐Bu3Ga–EPh3 (E = P 1 , As 2 , Sb 3 ) were synthesized by reactions of Ph3E and t‐Bu3Ga and characterized by heteronuclear NMR (1H, 13C (31P)) and IR spectroscopy, elemental analysis and single crystal X‐ray diffraction. Their structural parameters are discussed and compared to similar t‐Bu3Ga adducts. The strength of the donor‐acceptor interactions within 1 – 3 was investigated in solution by temperature‐dependent 1H NMR spectroscopy and by quantum chemical calculations. 相似文献
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Alla Kammerdiner Alexander Veremyev Eduardo Pasiliao 《Journal of Global Optimization》2017,67(1-2):187-205
In this paper, we introduce mathematical models for studying a supernetwork that is comprised of closely connected groups of subnetworks. For several related classes of such supernetworks, we explicitly derive an analytical representation of their Laplacian spectra. This work is motivated by an application of spectral graph theory in cooperative control of multi-agent networked systems. Specifically, we apply our graph-theoretic results to establish bounds on the speed of convergence and the communication time-delay for solving the average-consensus problem by a supernetwork of clusters of integrator agents. 相似文献
207.
Kateryna Fominova Taras Diachuk Dmitry Granat Taras Savchuk Vladyslav Vilchynskyi Oleksiy Svitlychnyi Vladyslav Meliantsev Igor Kovalchuk Eduard Litskan Vadym
V. Levterov Valentyn R. Badlo Ruslan I. Vaskevych Alla I. Vaskevych Andrii V. Bolbut Volodymyr V. Semeno Rustam Iminov Kostiantyn Shvydenko Anastasiia S. Kuznetsova Yurii V. Dmytriv Daniil Vysochyn Vasyl Ripenko Andrei A. Tolmachev Olexandra Pavlova Halyna Kuznietsova Iryna Pishel Petro Borysko Pavel K. Mykhailiuk 《Chemical science》2021,12(34):11294
A general approach to a new generation of spirocyclic molecules – oxa-spirocycles – was developed. The key synthetic step was iodocyclization. More than 150 oxa-spirocyclic compounds were prepared. Incorporation of an oxygen atom into the spirocyclic unit dramatically improved water solubility (by up to 40 times) and lowered lipophilicity. More potent oxa-spirocyclic analogues of antihypertensive drug terazosin were synthesized and studied in vivo.A general practical approach to a new generation of spirocyclic molecules – oxa-spirocycles – is developed. 相似文献
208.
Montserrat García-Alvarez Antxon Martínez de Ilarduya José Antonio Portilla Abdelilah Alla Sebastián Muñoz-Guerra 《Macromolecular Symposia》2008,273(1):85-94
Summary: Stoichiometric complexes of biotechnological poly(γ-glutamic) acid and poly(β,L -malic) acid with alkyltrimethylammonium surfactants of long alkyl chains could be readily prepared in aqueous medium. They adopt a biphasic layered structures in which the main chain and the side chain alternate with nanometric periodicity. Alkyl side chains show reversible melting that involves generation of mesophases. Complexes degraded by water by different mechanisms depending on the constitution of the main chain; the polymalic complexes underwent surface erosion whereas the polyglutamic ones degraded in bulk. Erythromycin could be homogenously loaded into the paraffinic subphase of the complexes and delivered upon incubation under physiological conditions in parallel to the hydrolysis of the polymer. 相似文献
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Multiplicity of the liquid-liquid phase transitions in supercooled water, first obtained in computer simulations [Brovchenko et al., J. Chem. Phys. 118, 9473 (2003)], has got strong support from the recent experimental observation of the two phase transitions between amorphous ices [Loerting et al., Phys. Rev. Lett. 96, 025702 (2006)]. These experimental results allow assignment of the four amorphous water phases (I-IV) obtained in simulations to the three kinds of amorphous ices. Water phase I (rho approximately 0.90 gcm(3)) corresponds to the low-density amorphous ice, phase III (rho approximately 1.10 gcm(3)) to the high-density amorphous ice, and phase IV (rho approximately 1.20 gcm(3)) to the very-high-density amorphous ice. Phase II of model water with density rho approximately 1.00 gcm(3) corresponds to the normal-density water. Such assignment is confirmed by the comparison of the structural functions of the amorphous phases of model water and real water. In phases I and II the first and second coordination shells are clearly divided. Phase I consists mainly of the four coordinated tetrahedrally ordered water molecules. Phase II is enriched with molecules, which have tetrahedrally ordered four nearest neighbors and up six molecules in the first coordination shell. Majority of the molecules in phase III still have tetrahedrally ordered four nearest neighbors. Transition from phase III to phase IV is characterized by a noticeable drop of tetrahedral order, and phase IV consists mainly of molecules with highly isotropic angular distribution of the nearest neighbors. Relation between the structures of amorphous water phases, crystalline ices, and liquid water is discussed. 相似文献