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排序方式: 共有347条查询结果,搜索用时 15 毫秒
1.
Nicolaisen  Jeppe  Frandsen  Tove Faber 《Scientometrics》2022,127(7):4167-4189
Scientometrics - Using a selection of general science journals, general medical journals and specialized medical journals, this paper analyses four indicators of epistemic community formation:...  相似文献   
2.
Electrolyte additives have been widely used to address critical issues in current metal (ion) battery technologies. While their functions as solid electrolyte interface forming agents are reasonably well-understood, their interactions in the liquid electrolyte environment remain rather elusive. This lack of knowledge represents a significant bottleneck that hinders the development of improved electrolyte systems. Here, the key role of additives in promoting cation (e.g., Li+) desolvation is unraveled. In particular, nitrate anions (NO3) are found to incorporate into the solvation shells, change the local environment of cations (e.g., Li+) as well as their coordination in the electrolytes. The combination of these effects leads to effective Li+ desolvation and enhanced battery performance. Remarkably, the inexpensive NaNO3 can successfully substitute the widely used LiNO3 offering superior long-term stability of Li+ (de-)intercalation at the graphite anode and suppressed polysulfide shuttle effect at the sulfur cathode, while enhancing the performance of lithium–sulfur full batteries (initial capacity of 1153 mAh g−1 at 0.25C) with Coulombic efficiency of ≈100% over 300 cycles. This work provides important new insights into the unexplored effects of additives and paves the way to developing improved electrolytes for electrochemical energy storage applications.  相似文献   
3.
Aspects of parallel wire cable reliability   总被引:1,自引:0,他引:1  
Recently developed models for the assessment of the strength and fatigue life of cables are presented and illustrated. The illustrations are based on experimental data and experience gained from the design and assessment of several major cable supported bridges. It is shown how inspection results may be used to update the reliability of cables. The procedure is illustrated using results of Ultra Sonic inspections. Finally, aspects of design and assessment of stay cables are considered. Special emphasis is given to the effect of design philosophy and corrosion protection on the resistance factors for the stay cable resistance.  相似文献   
4.
Scientometrics - The existence of gender disparities in academia is well documented. Many explanations have been proposed and productivity is one of the most used variables to explain a possible...  相似文献   
5.
Abstract: The present article addresses the development of a spatial information system (SIS), which aims to facilitate risk management of large‐scale concrete structures. The formulation of the SIS is based on ideas developed in the context of indicator‐based risk modeling for concrete structures subject to corrosion and geographical information system based risk modeling concerning large‐scale risk management. The term “risk management” here refers in particular to the process of condition assessment and optimization of the inspection and repair activities. The SIS facilitates the storage and handling of all relevant information to the risk management. The probabilistic modeling utilized in the condition assessment takes basis in a Bayesian hierarchical modeling philosophy. It facilitates the updating of risks as well as optimizing inspection plans whenever new information about the condition of the structure becomes available. In the SIS, the various data of relevance for the risk management can be visualized in three dimensions. This feature and the other functionalities of the SIS are illustrated in an example considering the Danish Farø bridges.  相似文献   
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7.
An electrodeposition technique has been adapted to produce copper–silicon carbide composites with honeycomb-like microstructures. The detrimental Cu–SiC reaction was avoided by using this room temperature processing technique. The wood-derived silicon carbide phase allows for tailorable microstructures due to the variety of available wood precursors. Plating efficiency for each wood type was determined using image analysis. This processing method results in the successful filling of pores with aspect ratios of up to 100.  相似文献   
8.
The production of printed electronics exhibits an enormous economical potential due to the possibility to manufacture innovative products at low cost. At the moment, one of the major challenges for the fabrication of printed electronics is the controllability of the material properties during processing and the miniaturization of the deposited structures. In this context, the application of soft lithographic techniques appears promising, because they allow a defined patterning of the materials in the range of few nanometers, which is far below the limits of other printing techniques like inkjet-printing or screen printing. This work proves the applicability of the soft lithographic technique micro-molding in capillaries (MIMIC) for the manufacture of conductive indium tin oxide (ITO) electrodes. For the creation of stable dispersions of ITO nano-sized particles, steric as well as electrostatic stabilization concepts are applied. The prepared dispersions are characterized with regard to the later processing via MIMIC. The geometry and the electrical properties of the soft lithographically deposited structures are determined to prove their functionality. Special attention is paid to the influence of the wetting behavior of the dispersions on the resulting geometry of the structures. Finally, the applicability of the optimized structures is demonstrated by the assembly of a thin film transistor (TFT), in which the deposited structures serve as source and drain electrodes.  相似文献   
9.
Porous acicular mullite (ACM) ceramics are known to be mechanically robust even at high porosities. This study was undertaken to better understand what aspects of acicular mullite's needle-like microstructure affect the overall mechanical properties and how the microstructure might be modified to improve mechanical performance. ACMs with a variety of porosities, pore sizes, and needle diameters were produced, and their elastic moduli, flexure strengths, and fracture toughnesses were measured. Three-dimensional image analysis was an invaluable tool in determining the needle diameters of these complex 3D network structures. It was found that porosity was the most dominant factor in determining the mechanical properties of ACM and that its behavior could be described using the Gibson–Ashby foam model.  相似文献   
10.
Acicular mullite (ACM) is a highly porous ceramic with a needlelike microstructure. Next-generation ACM-based diesel particulate filters will require porosities >60%, making optimizing ACM's mechanical properties a key area of interest. A prior study determined that, for the range of microstructures evaluated, the elastic modulus, strength, and fracture toughness were largely functions of total porosity and not needle or pore size, consistent with the Gibson–Ashby foam model. Therefore, alternate strengthening and toughening methods were sought. Doping the ACM precursor with either MgO or Nd2O3 produced ACM microstructures that appeared similar but had differing bulk mechanical properties. The mechanical properties of the mullite needles, the intergranular glassy phase, and the mullite–glass interface of the ACMs were investigated, but no major differences were found. Using X-ray computed tomography, a 3D imaging technique, it was found that MgO-doping of the ACM created a less uniform, and thus weaker, microstructure than Nd2O3-doping.  相似文献   
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