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61.
The mechanical and adhesion behavior of cationically polymerized, partially crystalline epoxy networks is presented. For this, a reactive and a nonreactive poly(?-caprolactone) (PCL) were used as the crystalline component for the formation of copolymers and polymer alloys, respectively. The trade-off between toughness on the one hand and glass transition temperature and mechanical strength on the other can be reduced by the presence of nanostructures in combination with small crystalline domains (相似文献   
62.
Based on the previously reported potent and selective sulfone hydroxamate inhibitors SC-76276, SC-78080 (SD-2590), and SC-77964, potent MMP inhibitors have been designed and synthesized to append a boron-rich carborane cluster by employing click chemistry to target tumor cells that are known to upregulate gelatinases. Docking against MMP-2 suggests binding involving the hydroxamate zinc-binding group, key H-bonds by the sulfone moiety with the peptide backbone residues Leu82 and Leu83, and a hydrophobic interaction with the deep P1’ pocket. The more potent of the two triazole regioisomers exhibits an IC50 of 3.7 nM versus MMP-2 and IC50 of 46 nM versus MMP-9.  相似文献   
63.
<正>多年来,重工业因高能耗、高污染,一直在可持续发展方面备受诟病。但事实也不完全如此。许多领先的重工业企业,尤其在公用事业、石油天然气和矿产领域,已开始重视可持续发展,并将其融入企业的日常运营当中。在全球各地,重工业企业需要获得比一般法规遵从更为严格的"运营许可",这不仅是法规的问题,也成为推动重工业可持续发展的首要动力。近年来发生的石油、采矿及核事故也说明了这一特殊  相似文献   
64.
Bio‐inspired layered ceramic‐polymer composites with high strength and toughness were prepared from sintered aluminum oxide ceramic sheets and cationically curing epoxy resins toughened with poly(ε‐caprolactone) (PCL). The architecture of the composite is inspired by nacre but is arranged on a larger scale. Ceramic sheets with a nominal thickness of 250 μm were assembled into composite plates by adhesive layers with a nominal thickness of 20 μm. Before the manufacturing of the composites, the stress‐strain properties of the polymer component were tailored by the variation in the PCL content between 0 and 39 wt%. For composites with 4 and 15 ceramic layers, the bending strengths achieved 327 MPa and 376 MPa, which are higher than that of pure ceramic sheets. Moreover, composites with 15 ceramic layers show a 16 times higher toughness compared to that of the pure ceramic sheets. The results indicate that the toughness of the layered composites increases significantly with the number of layers. Inspired by the geometrical ratio of the natural sheet composite nacre, we have achieved a similar strength but a 2 times higher toughness than nacre by only adding up to 6 vol% of the polymer.  相似文献   
65.
This article outlines advances in molecular modeling and simulation using massively parallel high‐performance computers (HPC). In the SkaSim project, partners from the HPC community collaborated with users from science and industry. The aim was to optimize the prediction of thermodynamic property data in terms of efficiency, quality and reliability using HPC methods. In this context, various topics were dealt with: atomistic simulation of homogeneous gas bubble formation, surface tension of classical fluids and ionic liquids, multicriteria optimization of molecular models, the development of the molecular simulation codes ls1 mardyn and ms2, atomistic simulation of gas separation processes, molecular membrane structure generators, transport resistors and the evaluation of predictive property data models based on specific mixture types.  相似文献   
66.
Quantum Information Processing - Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them....  相似文献   
67.
We use verified computations and the Lanczos process to obtain guaranteed lower and upper bounds on the 2-norm and the energy-norm error of an approximate solution to a symmetric positive definite linear system. The upper bounds require the a priori knowledge of a lower bound on the smallest eigenvalue.  相似文献   
68.
Mobile ad-hoc networks are networks spontaneously deployed from a set of mobile devices without requiring any fixed infrastructures. The increasing interest in this technology raises new research challenges towards providing them a management framework. Network users expect a service level as close as in regular fixed networks. A primary expectation is the capability to communicate (end-to-end) with the other network users. We present in this paper a framework for monitoring and optimizing this capability in mobile ad-hoc networks. Our normalized metric, called end-to-end connectivity degree, characterizes the number of nodes, that a node can reach in the entire network. We describe a management architecture to monitor this metric together with the network density, and illustrate how routing configuration can be performed to optimize it.  相似文献   
69.
Machine Intelligence Research - The success of new scientific areas can be assessed by their potential for contributing to new theoretical approaches aligned with real-world applications. The...  相似文献   
70.
Node‐link infographics are visually very rich and can communicate messages effectively, but can be very difficult to create, often involving a painstaking and artisanal process. In this paper we present an investigation of node‐link visualizations for communication and how to better support their creation. We begin by breaking down these images into their basic elements and analyzing how they are created. We then present a set of techniques aimed at improving the creation workflow by bringing more flexibility and power to users, letting them manipulate all aspects of a node‐link diagram (layout, visual attributes, etc.) while taking into account the context in which it will appear. These techniques were implemented in a proof‐of‐concept prototype called GraphCoiffure, which was designed as an intermediary step between graph drawing/editing software and image authoring applications. We describe how GraphCoiffure improves the workflow and illustrate its benefits through practical examples.  相似文献   
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