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排序方式: 共有7653条查询结果,搜索用时 15 毫秒
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Aysun apc Mlanie M. Lorion Hui Wang Nina Simon Maria Leidenberger Mariana C. BorgesSilva Diogo R. M. Moreira Yongping Zhu Yuqing Meng Jia Yun Chen Yew Mun Lee Oliver Friedrich Barbara Kappes Jigang Wang Lutz Ackermann Svetlana B. Tsogoeva 《Angewandte Chemie (International ed. in English)》2019,58(37):13161-13161
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Andreas Jaekel Pascal Lill Stephen Whitelam Barbara Sacc 《Molecules (Basel, Switzerland)》2020,25(23)
Since the pioneering work of Ned Seeman in the early 1980s, the use of the DNA molecule as a construction material experienced a rapid growth and led to the establishment of a new field of science, nowadays called structural DNA nanotechnology. Here, the self-recognition properties of DNA are employed to build micrometer-large molecular objects with nanometer-sized features, thus bridging the nano- to the microscopic world in a programmable fashion. Distinct design strategies and experimental procedures have been developed over the years, enabling the realization of extremely sophisticated structures with a level of control that approaches that of natural macromolecular assemblies. Nevertheless, our understanding of the building process, i.e., what defines the route that goes from the initial mixture of DNA strands to the final intertwined superstructure, is, in some cases, still limited. In this review, we describe the main structural and energetic features of DNA nanoconstructs, from the simple Holliday junction to more complicated DNA architectures, and present the theoretical frameworks that have been formulated until now to explain their self-assembly. Deeper insights into the underlying principles of DNA self-assembly may certainly help us to overcome current experimental challenges and foster the development of original strategies inspired to dissipative and evolutive assembly processes occurring in nature. 相似文献
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Barbara Niethammer Alessia Nota Sebastian Throm Juan J.L. Velázquez 《Journal of Differential Equations》2019,266(1):653-715
In this paper we consider the long-time asymptotics of a linear version of the Smoluchowski equation which describes the evolution of a tagged particle moving in a random distribution of fixed particles. The volumes v of these particles are independently distributed according to a probability distribution which decays asymptotically as a power law . The validity of the equation has been rigorously proved in [22] taking as a starting point a particle model and for values of the exponent , but the model can be expected to be valid, on heuristic grounds, for . The resulting equation is a non-local linear degenerate parabolic equation. The solutions of this equation display a rich structure of different asymptotic behaviors according to the different values of the exponent σ. Here we show that for the linear Smoluchowski equation is well-posed and that there exists a unique self-similar profile which is asymptotically stable. 相似文献
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Vsevolod Khikhlovskyi Albert J. J. M. van Breemen Jasper J. Michels René A. J. Janssen Gerwin H. Gelinck Martijn Kemerink 《Journal of Polymer Science.Polymer Physics》2015,53(17):1231-1237
In many organic electronic devices functionality is achieved by blending two or more materials, typically polymers or molecules, with distinctly different optical or electrical properties in a single film. The local scale morphology of such blends is vital for the device performance. Here, a simple approach to study the full 3D morphology of phase‐separated blends, taking advantage of the possibility to selectively dissolve the different components is introduced. This method is applied in combination with AFM to investigate a blend of a semiconducting and ferroelectric polymer typically used as active layer in organic ferroelectric resistive switches. It is found that the blend consists of a ferroelectric matrix with three types of embedded semiconductor domains and a thin wetting layer at the bottom electrode. Statistical analysis of the obtained images excludes the presence of a fourth type of domains. The criteria for the applicability of the presented technique are discussed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1231–1237 相似文献
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Dr. Júlia Mayans Dr. Constantinos C. Stoumpos Dr. Mercé Font-Bardia Prof. Albert Escuer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(49):11158-11169
An anionic hexanuclear NiII metallamacrocycle with endo and exo linking sites has been employed as a building block to generate a series of capsules and bowls of nanometric size. The supramolecular arrangement of the {Ni6} rings was tailored by the size of the alkali cations, showing the transition from {Ni6-M2-Ni6} capsules (M=LiI and NaI) to {Ni6-M} bowls (M=KI and CsI). The alkyl co-cations are determinant to stabilize the assemblies by means of CH⋅⋅⋅π interactions on the exo side of the metallamacrocycles. The effect on the topology of the supramolecular assemblies of the cation size, cation charge, Et3NH+ or Me4N+ counter cations has been analyzed. Magnetic measurements reveal the presence of ferromagnetic and antiferromagnetic interactions inside the rings that allow a S=0 ground state. 相似文献
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