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61.
Wurster Marco Michel Marius May Marvin Carl Kuhnle Andreas Stricker Nicole Lanza Gisela 《Journal of Intelligent Manufacturing》2022,33(2):575-591
Journal of Intelligent Manufacturing - Remanufacturing includes disassembly and reassembly of used products to save natural resources and reduce emissions. While assembly is widely understood in... 相似文献
62.
The diffusion coefficient \(D_{{{\text{O}}_{2} }}\), the porosity and the pore structure of mortars produced with a Portland cement and a range of blended cements containing limestone powder, microsilica, portlandite or slag were measured in the non-carbonated and the carbonated state. Additionally, the setup for measuring O2 diffusion was adapted to measure also the CO2 diffusion of the carbonated mortars. The diffusion coefficient \(D_{{{\text{O}}_{2} }}\) and the total porosity were increased in the mortars containing microsilica and slag, while they were decreased in the other mortars due to carbonation. Invariably, the pore structure became coarser in all samples. The relationship between diffusion coefficients \(D_{{{\text{O}}_{2} }}\) and \(D_{{{\text{CO}}_{2} }}\) in the carbonated mortars was always linear, with \(D_{{{\text{O}}_{2} }}\) systematically higher by factor of 1.37. As this factor broadly agrees with what was found in the scant literature about CO2 diffusion, it could be used for estimating \(D_{{{\text{CO}}_{2} }}\) of carbonated mortar and concrete based on measurements of O2 diffusion. 相似文献
63.
Jing Wang Andreas Mandelis Alexander Melnikov Qiming Sun 《International Journal of Thermophysics》2016,37(6):60
Colloidal quantum dots (CQDs) have attracted significant interest for applications in electronic and optoelectronic devices such as photodetectors, light-emitting diodes, and solar cells. However, a poor understanding of charge transport in these nanocrystalline films hinders their practical applications. The photocarrier radiometry (PCR) technique, a frequency-domain photoluminescence method spectrally gated for monitoring radiative recombination photon emissions while excluding thermal infrared photons due to non-radiative recombination, has been applied to PbS CQD thin films for the analysis of charge transport properties. Linear excitation intensity responses of PCR signals were found in the reported experimental conditions. The type and influence of trap states in the coupled PbS CQD thin film were analyzed with PCR temperature- and time-dependent results. 相似文献
64.
Decoupling Charge Transport and Electroluminescence in a High Mobility Polymer Semiconductor 下载免费PDF全文
65.
66.
A Review of Metal Fabricated with Laser‐ and Powder‐Bed Based Additive Manufacturing Techniques: Process,Nomenclature, Materials,Achievable Properties,and its Utilization in the Medical Sector 下载免费PDF全文
67.
68.
Andreas Nägelein Matthias Steidl Stefan Korte Bert Voigtländer Werner Prost Peter Kleinschmidt Thomas Hannappel 《Nano Research》2018,11(11):5924-5934
Profiling of the electrical properties of nanowires (NWs) and NW heterocontacts with high spatial resolution is a challenge for any application and advanced NW device development. For appropriate NW analysis, we have established a four-point prober, which is combined in vacuo with a state-of-the-art vapor-liquid-solid preparation, enabling contamination-free NW characterization with high spatial resolution. With this ultrahigh-vacuum-based multi-tip scanning tunneling microscopy (MT-STM), we obtained the resistance and doping profiles of freestanding NWs, along with surface-sensitive information. Our in-system 4-probe STM approach decreased the detection limit for low dopant concentrations to the depleted case in upright standing NWs, while increasing the spatial resolution and considering radial depletion regions, which may originate from surface changes. Accordingly, the surface potential of oxide-free GaAs NW {112} facets has been estimated to be lower than 20 mV, indicating a NW surface with very low surface state density. 相似文献
69.
Andreas Goralczyk Sofya Savicheva Ramin Montazeri Simona Fine Fadoua Mayoussi Pang Zhu Kay Steffen Frederik Kotz-Helmer Dorothea Helmer Bastian E. Rapp 《Advanced Engineering Materials》2023,25(8):2201314
Superhydrophobic coatings are widely applicable, e.g., as self-cleaning surfaces or water–oil separation membranes, yet their wider usage is impeded due to costs of fabrication, size, or substrate limitation. Spray-coating is a versatile coating procedures and might offer a good solution for the fabrication of these superhydrophobic coatings, due to the fact that coatings can be fabricated on various materials in a simple, fast, and inexpensive manner. Most procedures rely on hybrid coatings of hydrophobized nanoparticles and a polymeric matrix, which have several drawbacks including the easy loss of nanoparticles and difficult waste handling. Here, the fabrication of the superhydrophobic material, called Fluoropor, for the first time, by spray-coating on various substrates including metals, tissues, concrete, and glass is presented. It is fabricated by spray-coating a mixture of a highly fluorinated monomer blended with porogens followed by photopolymerization. The superhydrophobicity of the material relies on the porous structure on the micro-/nanoscale across the bulk material and does not require any nanoparticles. Excellent self-cleaning ability of these coatings, resistance against thermal and abrasive impact, and their application as oil–water separation membranes are shown. This versatile applicability is highly promising for real-world application as self-cleaning coatings or oil–water separating membranes. 相似文献
70.
Andreas Förner Jan Vollhüter Anna Krapf Abdullah Jamjoom Daniel Hausmann Benjamin Wahlmann Zongwen Fu Carolin Körner Steffen Neumeier Mathias Göken 《Advanced Engineering Materials》2023,25(15):2300407
By increasing the density of interfaces in NiAl–CrMo in situ composites, the mechanical properties can be significantly improved compared to conventionally cast material. The refined microstructure is achieved by manufacturing through electron beam powder bed fusion (PBF-EB). By varying the process parameters, an equiaxed or columnar cell morphology can be obtained, exhibiting a plate-like or an interconnected network of the (Cr,Mo) reinforcement phase which is embedded in a NiAl matrix. The microstructure of the different cell morphologies is investigated in detail using scanning electron microscope, transmission electron microscopy, and atom probe tomography. For both morphologies, the mechanical properties at elevated temperatures are analyzed by compression and creep experiments parallel and perpendicular to the building direction. In comparison to cast NiAl and NiAl–(Cr, Mo), the yield strength of the PBF-EB fabricated specimens is significantly improved at temperatures up to 1,027 °C. While the columnar morphology exhibits the best improved mechanical properties at high temperatures, the equiaxial morphology shows nearly ideal isotropic mechanical behavior, which is a substantial advantage over directionally solidified material. 相似文献