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In this article an attempt is made to simplify the application of EC 6 by a strict and clear division of the EC 6 into calculation, execution and materials. The calculation engineer does not, therefore, need to get involved with building materials specific parameters, which make it much more difficult to get a view over the variety of possible combinations. The introduction of classes in the characteristics that are relevant for building materials means that the structural engineer specifies suitable quantities necessary for his task, the builder/product manufacturer by suitable methods and choice of unit/mortar combinations achieves the required classes and, the product manufacturer, in particular, should be entitled to have the possibility of the individual specification, e. g. as part of general appraisal certificates.  相似文献   

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Attachment of Li+ ion on graphene surface to realize Li+‐ion conductor is a real challenge because of the weak interaction between the ions and the functional groups of graphene oxide; although, a large number of theoretical results are already available in the literature. To overcome this problem, graphene oxide is functionalized by 1‐aza‐15‐crown‐5, the cage‐like structure containing four oxygens that can bind Li+ ion through electrostatic interaction. Li+ migration on graphene surface has been investigated using ac relaxation mechanism. Perfect Debye‐type relaxation behavior with β (relaxation exponent) value ≈1 resulting from single ion is observed. The activation energy of Li+ migration arising due to cation‐π interaction is found to be 0.37 eV, which agrees well with recently reported theoretical value. It is believed that this study will help to design isolated ion conductors for Li+‐ion battery.  相似文献   

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A facile two‐step solution‐phase method has been developed for the preparation of hierarchical α‐MnO2 nanowires@Ni1‐xMnxOy nanoflakes core–shell nanostructures. Ultralong α‐MnO2 nanowires were synthesized by a hydrothermal method in the first step. Subsequently, Ni1‐xMnxOy nanoflakes were grown on α‐MnO2 nanowires to form core–shell nanostructures using chemical bath deposition followed by thermal annealing. Both solution‐phase methods can be easily scaled up for mass production. We have evaluated their application in supercapacitors. The ultralong one‐dimensional (1D) α‐MnO2 nanowires in hierarchical core–shell nanostructures offer a stable and efficient backbone for charge transport; while the two‐dimensional (2D) Ni1‐xMnxOy nanoflakes on α‐MnO2 nanowires provide high accessible surface to ions in the electrolyte. These beneficial features enable the electrode with high capacitance and reliable stability. The capacitance of the core–shell α‐MnO2@Ni1‐xMnxOy nanostructures (x = 0.75) is as high as 657 F g?1 at a current density of 250 mA g?1, and stable charging‐discharging cycling over 1000 times at a current density of 2000 mA g?1 has been realized.  相似文献   

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In the specific context of condensed media, the significant and increasing recent interest in the α‐cyanostilbene (CS) motif [? Ar? CH?C(CN)? Ar? ] is relevant. These compounds have shown remarkable optical features in addition to interesting electrical properties, and hence they are recognized as very suitable and versatile options for the development of functional materials. This progress report is focused on current and future use of CS structures and molecular assemblies with the aim of exploring and developing for the next generations of functional materials. A critical selection of illustrative materials that contain the CS motif, including relevant subfamilies such as the dicyanodistyrylbenzene and 2,3,3‐triphenylacrylonitrile shows how, driven by the self‐assembly of CS blocks, a variety of properties, effects, and possibilities for practical applications can be offered to the scientific community, through different rational routes for the elaboration of advanced materials. A survey is provided on the research efforts directed toward promoting the self‐assembly of the solid state (polycrystalline solids, thin films, and single crystals), liquid crystals, nanostructures, and gels with multistimuli responsiveness, and applications for sensors, organic light‐emitting diodes, organic field effect transistors, organic lasers, solar cells, or bioimaging purposes.  相似文献   

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Interleukin 1 beta (IL‐1β)‐dependent inflammatory disorders, such as rheumatoid arthritis and psoriasis, pose a serious medical burden worldwide, where patients face a lifetime of illness and treatment. Organogold compounds have been used since the 1930s to treat rheumatic and other IL‐1β‐dependent diseases and, though their mechanisms of action are still unclear, there is evidence that gold interferes with the transmission of inflammatory signalling. Here we show for the first time that citrate‐stabilized gold nanoparticles, in a size dependent manner, specifically downregulate cellular responses induced by IL‐1β both in vitro and in vivo. Our results indicate that the anti‐inflammatory activity of gold nanoparticles is associated with an extracellular interaction with IL‐1β, thus opening potentially novel options for further therapeutic applications.  相似文献   

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Rechargeable Zn/MnO2 batteries using mild aqueous electrolytes are attracting extensive attention due to their low cost, high safety, and environmental friendliness. However, the charge‐storage mechanism involved remains a topic of controversy so far. Also, the practical energy density and cycling stability are still major issues for their applications. Herein, a free‐standing α‐MnO2 cathode for aqueous zinc‐ion batteries (ZIBs) is directly constructed with ultralong nanowires, leading to a rather high energy density of 384 mWh g?1 for the entire electrode. Greatly, the H+/Zn2+ coinsertion mechanism of α‐MnO2 cathode for aqueous ZIBs is confirmed by a combined analysis of in situ X‐ray diffractometry, ex situ transmission electron microscopy, and electrochemical methods. More interestingly, the Zn2+‐insertion is found to be less reversible than H+‐insertion in view of the dramatic capacity fading occurring in the Zn2+‐insertion step, which is further evidenced by the discovery of an irreversible ZnMn2O4 layer at the surface of α‐MnO2. Hence, the H+‐insertion process actually plays a crucial role in maintaining the cycling performance of the aqueous Zn/α‐MnO2 battery. This work is believed to provide an insight into the charge‐storage mechanism of α‐MnO2 in aqueous systems and paves the way for designing aqueous ZIBs with high energy density and long‐term cycling ability.  相似文献   

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This paper presents further assessments of the previously reported round‐robin fatigue data obtained from high‐frequency mechanical impact (HFMI)‐improved longitudinal welds. A detailed statistical analyses of geometry measurements of HFMI‐treated weld toe profiles are presented. The fatigue analyses based on notch stress as defined by the International Institute of Welding are performed using the finite element method. Notch stresses are assessed based on both the fictitious weld toe radius and the addition of measured actual notch radius to the fictitious radius. While no large differences are observed between the results of methods, the former one is found to be more practical and faster to implement from the end‐user point of view.  相似文献   

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