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141.
Thomas Schareina Xiao-Feng Wu Alexander Zapf Alain Cotté Matthias Gotta Matthias Beller 《Topics in Catalysis》2012,55(7-10):426-431
The first copper-catalyzed trifluoromethylation of aryl halides was developed that utilizes inexpensive trifluoroacetates. Providing low concentrations of the most economically attractive and atom-efficient trifluoromethylation reagent this new protocol is advantageous compared to known procedures both economically and ecologically. 相似文献
142.
This paper presents a model of firm and market dynamics that is able to reproduce the empirically observed patterns on firm growth and its statistical characteristics. It goes beyond the existing firm models by reproducing all stylized facts established in the literature. Furthermore, the model is flexible in the sense that various parameter settings are identified that reproduce the stylized facts. We identify and discuss different ranges of the model’s parameters that allow for adapting the model to certain industries and life-cycle stages. 相似文献
143.
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145.
J Wuttke A Budwig M Drochner H Kämmerling FJ Kayser H Kleines V Ossovyi LC Pardo M Prager D Richter GJ Schneider H Schneider S Staringer 《The Review of scientific instruments》2012,83(7):075109
SPHERES is a third-generation neutron backscattering spectrometer, located at the 20 MW German neutron source FRM II and operated by the Ju?lich Centre for Neutron Science. It offers an energy resolution (fwhm) better than 0.65 μeV, a dynamic range of ±?31 μeV, and a signal-to-noise ratio of up to 1750:1. 相似文献
146.
Cemernek David Cemernek Sandra Gursch Heimo Pandeshwar Ashwini Leitner Thomas Berger Matthias Klösch Gerald Kern Roman 《Journal of Intelligent Manufacturing》2022,33(6):1561-1579
Journal of Intelligent Manufacturing - Continuous casting is the most important route for the production of steel today. Due to the physical, mechanical, and chemical components involved in the... 相似文献
147.
Suhaib Koji Baydoun Matthias Voigt Christopher Jelich Steffen Marburg 《International journal for numerical methods in engineering》2020,121(2):187-200
The solution of frequency dependent linear systems arising from the discretization of vibro-acoustic problems requires a significant computational effort in the case of rapidly varying responses. In this paper, we review the use of a greedy reduced basis scheme for the efficient solution in a frequency range. The reduced basis is spanned by responses of the system at certain frequencies that are chosen iteratively based on the response that is currently worst approximated in each step. The approximations at intermediate frequencies as well as the a posteriori estimations of associated errors are computed using a least squares solver. The proposed scheme is applied to the solution of an interior acoustic problem with boundary element method (BEM) and to the solution of coupled structural acoustic problems with finite element method and BEM. The computational times are compared to those of a conventional frequencywise strategy. The results illustrate the efficiency of the method. 相似文献
148.
Regler Benjamin Scheffler Matthias Ghiringhelli Luca M. 《Data mining and knowledge discovery》2022,36(5):1815-1864
Data Mining and Knowledge Discovery - The identification of relevant features, i.e., the driving variables that determine a process or the properties of a system, is an essential part of the... 相似文献
149.
Yuan Yu Matteo Cagnoni Oana Cojocaru‐Mirdin Matthias Wuttig 《Advanced functional materials》2020,30(8)
Thermoelectric materials have attracted significant research interest in recent decades due to their promising application potential in interconverting heat and electricity. Unfortunately, the strong coupling between the material parameters that determine thermoelectric efficiency, i.e., the Seebeck coefficient, electrical conductivity, and thermal conductivity, complicates the optimization of thermoelectric energy converters. Main‐group chalcogenides provide a rich playground to alleviate the interdependence of these parameters. Interestingly, only a subgroup of octahedrally coordinated chalcogenides possesses good thermoelectric properties. This subgroup is also characterized by other outstanding characteristics suggestive of an exceptional bonding mechanism, which has been coined metavalent bonding. This conclusion is further supported by a map that separates different bonding mechanisms. In this map, all octahedrally coordinated chalcogenides with good performance as thermoelectrics are located in a well‐defined region, implying that the map can be utilized to identify novel thermoelectrics. To unravel the correlation between chemical bonding mechanism and good thermoelectric properties, the consequences of this unusual bonding mechanism on the band structure are analyzed. It is shown that features such as band degeneracy and band anisotropy are typical for this bonding mechanism, as is the low lattice thermal conductivity. This fundamental understanding, in turn, guides the rational materials design for improved thermoelectric performance by tailoring the chemical bonding mechanism. 相似文献
150.
Research has emphasized the importance of employees' individual entrepreneurial decision making for innovation. In this context, practised creativity as the ability to perceive and exploit creative opportunities, can be regarded as a crucial requirement for employees in new product development. We discuss the application of decision making logic as an important antecedent of practised creativity in new product development. We survey 219 employees from new product development departments of German product and service firms. Results indicate that the use of entrepreneurial decision making logic positively impacts practised creativity; comparably we find indicators that the use of causal decision making logic negatively influences creativity. The effects significantly depend on the moderating role of uncertainty. The results contribute to the literature of creativity, entrepreneurship and new product development by theoretically and empirically revealing effectuation as antecedent to practised creativity. The results open promising avenues for future research and allow the derivation of valuable guidelines for practitioners. Aligning the new product development process to support employees' entrepreneurial decision making may help generating practised creativity. 相似文献