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991.
Matthias Rudolf Guertler Nathalie Sick 《International Journal of Project Management》2021,39(2):102-114
Open Innovation (OI) facilitates a multitude of innovation opportunities through allowing access to a broad variety of external partners, expertise and knowledge. Although OI has been established in academia and the corporate world, implementation by SMEs remains a formidable challenge, especially concerning the identification and selection of suitable OI partners. Given methodical support for such an endeavour is currently lacking, this article investigates how project management can support OI projects. Based on evidence from an exploratory multi-case study with four SMEs, this article develops a Situational Open Innovation framework that provides methodical support for SMEs in leveraging the complementarities between OI and project management towards effective partner search and selection. The findings illustrate how sensing capabilities for OI opportunities can benefit from systematic problem and stakeholder analyses as they allow for identifying and focussing on the most relevant innovation tasks and partners. 相似文献
992.
Jan Steinhoff Evgenia Charlafti Laura Reinecke Matthias Kraume Hans-Jörg Bart 《加拿大化工杂志》2020,98(1):384-393
This contribution presents a standardized experimental setup for the development of gravity separators. Two different optical measurement techniques for the characterization of the inlet and outlet dispersion with a droplet spectrum of 20-2000 μm are used. The settling behaviour in a standardized batch settling test (ERICAA cell) serves as a basis for predicting the drop diameter resolved separation efficiency of a horizontal continuous separator. The latter (DN150, length 0.65 m) was operated and monitored with a phase fraction of up to 15% and a load of up to 17.0 m3 m−2 h−1. A paraffin oil with a viscosity of 10 mPa s was the dispersed and water the continuous phase. Sauter mean diameters of dispersions measured inline show a good agreement with those calculated from batch settling tests. Additionally, the modelled separation efficiencies are compared to the experimental results produced with the continuous separator. 相似文献
993.
Methanol production is one promising way to minimize the ecological impact of the conventional steelmaking process. This synthesis needs additional hydrogen, preferably produced from a green power source. In this paper, the influence of different power supply scenarios, gas storage volumes, and hydrogen production capacities on the overall carbon saving potential – defined as carbon binding ratio – from a flexible methanol production case will be investigated. A mixed-integer linear programming model with rolling horizon is used to calculate the optimal production plan. 相似文献
994.
995.
Benjamin Seisenbacher Matthias Hofinger Gerhard Winter Florian Grün 《Fatigue & Fracture of Engineering Materials & Structures》2020,43(1):191-200
Dual hardening steels are a group of metals, which reach their material properties through a combination of strengthening via carbides and intermetallic precipitates. Because of their combination of mechanical properties, dual hardening steels are a promising alloying concept for hot‐work applications. The applied materials for hot‐work applications have to meet certain requirements, such as high hardness, high thermal strength, thermal stability, and fracture toughness. In this paper, a dual hardening steel in different heat treatment conditions was tested under out‐of‐phase thermomechanical loading conditions. All tests were done under full reverse strain control and the minimum temperature was kept constant. In the thermomechanical fatigue tests, solution annealed samples reached higher lifetimes compared with aged specimens. The hardness measurements show that the starting procedure of the thermomechanical fatigue leads to an increase of the hardness approximate to the values of the specimens with the ageing heat treatment. Cyclic softening can be observed in the test with the highest maximum temperature of 600°C. An increase of the maximum temperature also causes a decrease of the lifetime. 相似文献
996.
Qing Li Zhu Chen Fei Dai Daniel Wagner Matthias Daab Wei Hong Josef Breu Qiang Zheng Zi Liang Wu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2005567
Living organisms use musculatures with spatially distributed anisotropic structures to actuate deformations and locomotion with fascinating functions. Replicating such structural features in artificial materials is of great significance yet remains a big challenge. Here, a facile strategy is reported to fabricate hydrogels with elaborate ordered structures of nanosheets (NSs) oriented under a distributed electric field. Multiple electrodes are distributed with various arrangements in the precursor solution containing NSs and gold nanoparticles. A complex electric field induces sophisticated orientations of the NSs that are permanently inscribed by subsequent photo-polymerization. The resultant anisotropic nanocomposite poly(N-isopropylacrylamide) hydrogels exhibit rapid deformation upon heating or photoirradiation, owing to the fast switching of permittivity of the media and electric repulsion between the NSs. The complex alignments of NSs and anisotropic shape change of discrete regions result in programmed deformation of the hydrogels into various configurations. Furthermore, locomotion is realized by a spatiotemporal light stimulation that locally triggers time-variant shape change of the composite hydrogel with complex anisotropic structures. Such a strategy on the basis of the distributed electric-field-generated ordered structures should be applicable to gels, elastomers, and thermosets loaded with other anisotropic particles or liquid crystals, for the design of biomimetic/bioinspired materials with specific functionalities. 相似文献
997.
998.
A unified picture of different application areas for incipient metals is presented. This unconventional material class includes several main-group chalcogenides, such as GeTe, PbTe, Sb2Te3, Bi2Se3, AgSbTe2 and Ge2Sb2Te5. These compounds and related materials show a unique portfolio of physical properties. A novel map is discussed, which helps to explain these properties and separates the different fundamental bonding mechanisms (e.g., ionic, metallic, and covalent). The map also provides evidence for an unconventional, new bonding mechanism, coined metavalent bonding (MVB). Incipient metals, employing this bonding mechanism, also show a special bond breaking mechanism. MVB differs considerably from resonant bonding encountered in benzene or graphite. The concept of MVB is employed to explain the unique properties of materials utilizing it. Then, the link is made from fundamental insights to application-relevant properties, crucial for the use of these materials as thermoelectrics, phase change materials, topological insulators or as active photonic components. The close relationship of the materials' properties and their application potential provides optimization schemes for different applications. Finally, evidence will be presented that for metavalently bonded materials interesting effects arise in reduced dimensions. In particular, the consequences for the crystallization kinetics of thin films and nanoparticles will be discussed in detail. 相似文献
999.
F. Max Yavitt Tobin E. Brown Ella A. Hushka Monica E. Brown Nikolche Gjorevski Peter J. Dempsey Matthias P. Lutolf Kristi S. Anseth 《Advanced materials (Deerfield Beach, Fla.)》2020,32(30):1905366
Intestinal organoids are useful in vitro models for basic and translational studies aimed at understanding and treating disease. However, their routine culture relies on animal-derived matrices that limit translation to clinical applications. In fact, there are few fully defined, synthetic hydrogel systems that allow for the expansion of intestinal organoids. Here, an allyl sulfide photodegradable hydrogel is presented, achieving rapid degradation through radical addition-fragmentation chain transfer (AFCT) reactions, to support routine passaging of intestinal organoids. Shear rheology to first characterize the effect of thiol and allyl sulfide crosslink structures on degradation kinetics is used. Irradiation with 365 nm light (5 mW cm−2) in the presence of a soluble thiol (glutathione at 15 × 10−3 m ), and a photoinitiator (lithium phenyl-2,4,6-trimethylbenzoylphosphinate at 1 × 10−3 m ), leads to complete hydrogel degradation in less than 15 s. Allyl sulfide hydrogels are used to support the formation of epithelial colonies from single intestinal stem cells, and rapid photodegradation is used to achieve repetitive passaging of stem cell colonies without loss in morphology or organoid formation potential. This platform could support long-term culture of intestinal organoids, potentially replacing the need for animal-derived matrices, while also allowing systematic variations to the hydrogel properties tailored for the organoid of interest. 相似文献
1000.
Theory of Computing Systems - The study of representations for propositional theories has been a central subject in knowledge compilation. Many known representations of propositional knowledge... 相似文献