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151.
152.
Huibin He Jan‐Erik Ostwaldt Christoph Hirschhuser Carsten Schmuck Jochen Niemeyer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(28)
The dual pH‐induced reversible self‐assembly (PIRSA) of Au‐nanoparticles (Au NPs) is reported, based on their decoration with the self‐complementary guanidiniocarbonyl pyrrole carboxylate zwitterion (GCPZ). The assembly of such functionalized Au NPs is found at neutral pH, based on supramolecular pairing of the GCPZ groups. The resulting self‐assembled system can be switched back to the disassembled state by addition of base or acid. Two predominant effects that contribute to the dual‐PIRSA of Au NPs are identified, namely the ionic hydrogen bonding between the GCPZ groups, but also a strong hydrophobic effect. The contribution of each interaction is depending on the concentration of GCPZ on NPs, which allows to control the self‐assembly state over a wide range of different water/solvent ratios. 相似文献
153.
OR Spectrum - For online retailers with attended home delivery business models, the decisive factor for promising dynamic time slot pricing decisions is the quality of the opportunity cost... 相似文献
154.
Dr.‐Ing. Jochen Schwarz Dr.‐Ing. Holger Maiwald Christian Kaufmann Dipl.‐Ing Tobias Langhammer Dipl.‐Ing. Dr.‐Ing. Silke Beinersdorf 《Mauerwerk》2019,23(4):246-264
The European Macroseismic Scale 1998 – (EMS 98) is an instrument for the natural hazard of earthquakes, which allows the explanation of observed differences in the behaviour of the prevailing construction types by introducing and implementing vulnerability classes. The EMS 98 enables also the identification of purely empirically justified ranges of scatter. The basic methodology is also applicable to other natural hazards such as flood, tsunami and wind. This permits the development of a unified methodology for the consideration of building vulnerability in the sense of a multi‐hazard approach. For the first time, a vulnerability‐oriented instrument is available to evaluate a building stock for different natural hazards according to criteria that have been standardised in terms of engineering. The multi‐hazard vulnerability with its possible scatters is examined and visualized on real building inventories. With the concept of ”LEGOisation“ the existing buildings, a novel approach is presented to allow the sub‐structuring of buildings into storeys (including roof, basement and floors) to further development of the classification towards specific damage characteristics and local vulnerability. A still to be developed ”Conceptual Simulation Tool“ is described as an outlook. This uses the tools and methods developed to simulate damage and losses as a result of various natural hazards and their sequences. 相似文献
155.
Xiaofei Yang Xuejie Gao Qian Sun Sara Panahian Jand Ying Yu Yang Zhao Xia Li Keegan Adair Liang‐Yin Kuo Jochen Rohrer Jianneng Liang Xiaoting Lin Mohammad Norouzi Banis Yongfeng Hu Hongzhang Zhang Xianfeng Li Ruying Li Huamin Zhang Payam Kaghazchi Tsun‐Kong Sham Xueliang Sun 《Advanced materials (Deerfield Beach, Fla.)》2019,31(25)
Lithium–sulfur (Li–S) batteries with high sulfur loading are urgently required in order to take advantage of their high theoretical energy density. Ether‐based Li–S batteries involve sophisticated multistep solid–liquid–solid–solid electrochemical reaction mechanisms. Recently, studies on Li–S batteries have widely focused on the initial solid (sulfur)–liquid (soluble polysulfide)–solid (Li2S2) conversion reactions, which contribute to the first 50% of the theoretical capacity of the Li–S batteries. Nonetheless, the sluggish kinetics of the solid–solid conversion from solid‐state intermediate product Li2S2 to the final discharge product Li2S (corresponding to the last 50% of the theoretical capacity) leads to the premature end of discharge, resulting in low discharge capacity output and low sulfur utilization. To tackle the aforementioned issue, a catalyst of amorphous cobalt sulfide (CoS3) is proposed to decrease the dissociation energy of Li2S2 and propel the electrochemical transformation of Li2S2 to Li2S. The CoS3 catalyst plays a critical role in improving the sulfur utilization, especially in high‐loading sulfur cathodes (3–10 mg cm?2). Accordingly, the Li2S/Li2S2 ratio in the discharge products increased to 5.60/1 from 1/1.63 with CoS3 catalyst, resulting in a sulfur utilization increase of 20% (335 mAh g?1) compared to the counterpart sulfur electrode without CoS3. 相似文献
156.
Claas Willem Visser Dahlia N. Amato Jochen Mueller Jennifer A. Lewis 《Advanced materials (Deerfield Beach, Fla.)》2019,31(46)
Polymer foams are cellular solids composed of solid and gas phases, whose mechanical, thermal, and acoustic properties are determined by the composition, volume fraction, and connectivity of both phases. A new high‐throughput additive manufacturing method, referred to as direct bubble writing, for creating polymer foams with locally programmed bubble size, volume fraction, and connectivity is reported. Direct bubble writing relies on rapid generation and patterning of liquid shell–gas core droplets produced using a core–shell nozzle. The printed polymer foams are able to retain their overall shape, since the outer shell of these bubble droplets consist of a low‐viscosity monomer that is rapidly polymerized during the printing process. The transition between open‐ and closed‐cell foams is independently controlled by the gas used, while the foam can be tailored on‐the‐fly by adjusting the gas pressure used to produce the bubble droplets. As exemplars, homogeneous and graded polymer foams in several motifs, including 3D lattices, shells, and out‐of‐plane pillars are fabricated. Conductive composite foams with controlled stiffness for use as soft pressure sensors are also produced. 相似文献
157.
Alex Chortos Jie Mao Jochen Mueller Ehsan Hajiesmaili Jennifer A. Lewis David R. Clarke 《Advanced functional materials》2021,31(22):2010643
Active soft materials that change shape on demand are of interest for a myriad of applications, including soft robotics, biomedical devices, and adaptive systems. Despite recent advances, the ability to rapidly design and fabricate active matter in complex, reconfigurable layouts remains challenging. Here, the 3D printing of core-sheath-shell dielectric elastomer fibers (DEF) and fiber bundles with programmable actuation is reported. Complex shape morphing responses are achieved by printing individually addressable fibers within 3D architectures, including vertical coils and fiber bundles. These DEF devices exhibit resonance frequencies up to 700 Hz and lifetimes exceeding 2.6 million cycles. The multimaterial, multicore-shell 3D printing method opens new avenues for creating active soft matter with fast programable actuation. 相似文献
158.
Although IS research acknowledges the importance of path dependence with the generalized response that “history matters,” this broad understanding does not substitute for a more systematic historical analysis of how paths emerge and how technological change breaks them. In this context, we draw on the theory of strategic path dependence from organization and management research to develop a more nuanced understanding of path dependence and then explore how technological change breaks these strategic paths. Based on a narrative analysis of the strategic development of incumbents in the funeral industry, we reconstruct the core components of strategic paths – strategic patterns and self-reinforcing mechanisms – and scrutinize the Internet’s role in breaking these paths. We suggest that technological change helps break strategic paths by destabilizing the very self-reinforcing mechanisms that led to their emergence and reproduction in the first place. Furthermore, by showing that breaking strategic paths involves a subsequent critical event that destabilizes the strategic pattern, we advance a process understanding of how strategic paths are broken. This paper thus provides much-needed historical analyses of IS-related phenomena, offers a more precise and systematic understanding of path dependence in IS research, and yields insights into the process of how strategic paths are broken. 相似文献
159.
Electrochemical characterization of laser‐carbonized polyacrylonitrile nanofiber nonwovens 下载免费PDF全文
Dennis Go Martin Opitz Philipp Lott Khosrow Rahimi Jochen Stollenwerk Helga Thomas Martin Möller Bernhard Roling Alexander J. C. Kuehne 《应用聚合物科学杂志》2018,135(25)
Porous carbon materials represent prospective materials for absorbers, filters, and electronic applications. Carbon fibers with high surface areas can be produced from polyacrylonitrile and spun as thin fibers from solution. The resulting polymer fibers are first stabilized to obtain conjugated ribbons and then carbonized to graphitic structures in a second high‐temperature step in an inert atmosphere. In this study, we investigated a previously described fast laser‐heating process that delivered fibers with a higher crystallinity and surface area compared to the thermally carbonized fibers. In a subsequent KOH‐activation step, the crystalline domains were exfoliated, and the surface of the fibers became macroporous. This led to a reduced specific surface area but a higher capacitance compared to thermally carbonized nanofibers. We report the electrochemical properties of the electrochemical cells and discuss their potential applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46398. 相似文献
160.