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81.
82.
Christian Balischewski Hyung-Seok Choi Karsten Behrens Alkit Beqiraj Thomas Körzdörfer André Geßner Dr. Armin Wedel Prof. Dr. Andreas Taubert 《ChemistryOpen》2021,10(2):272-295
Metal sulfides are among the most promising materials for a wide variety of technologically relevant applications ranging from energy to environment and beyond. Incidentally, ionic liquids (ILs) have been among the top research subjects for the same applications and also for inorganic materials synthesis. As a result, the exploitation of the peculiar properties of ILs for metal sulfide synthesis could provide attractive new avenues for the generation of new, highly specific metal sulfides for numerous applications. This article therefore describes current developments in metal sulfide nanoparticle synthesis as exemplified by a number of highlight examples. Moreover, the article demonstrates how ILs have been used in metal sulfide synthesis and discusses the benefits of using ILs over more traditional approaches. Finally, the article demonstrates some technological challenges and how ILs could be used to further advance the production and specific property engineering of metal sulfide nanomaterials, again based on a number of selected examples. 相似文献
83.
Effect of nonlinear correlations on the statistics of return intervals in multifractal data sets 总被引:1,自引:0,他引:1
We study the statistics of return intervals between events above a certain threshold in multifractal data sets without linear correlations. We find that nonlinear correlations in the record lead to a power-law (i) decay of the autocorrelation function of the return intervals, (ii) increase in the conditional return period, and (iii) decay in the probability density function of the return intervals. We show explicitly that all the observed quantities depend both on the threshold value and system size, and hence there is no simple scaling observed. We also demonstrate that this type of behavior can be observed in real economic records and can be used to improve considerably risk estimation. 相似文献
84.
85.
Excellent passivation of thin silicon wafers by HF‐free hydrogen plasma etching using an industrial ICPECVD tool
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Muzhi Tang Jia Ge Johnson Wong Zhi Peng Ling Torsten Dippell Zhenhao Zhang Marco Huber Manfred Doerr Oliver Hohn Peter Wohlfart Armin Gerhard Aberle Thomas Mueller 《固体物理学:研究快报》2015,9(1):47-52
In this work, hydrogen plasma etching of surface oxides was successfully accomplished on thin (~100 µm) planar n‐type Czochralski silicon wafers prior to intrinsic hydrogenated amorphous silicon [a‐Si:H(i)] deposition for heterojunction solar cells, using an industrial inductively coupled plasma‐enhanced chemical vapour deposition (ICPECVD) platform. The plasma etching process is intended as a dry alternative to the conventional wet‐chemical hydrofluoric acid (HF) dip for solar cell processing. After symmetrical deposition of an a‐Si:H(i) passivation layer, high effective carrier lifetimes of up to 3.7 ms are obtained, which are equivalent to effective surface recombination velocities of 1.3 cm s–1 and an implied open‐circuit voltage (Voc) of 741 mV. The passivation quality is excellent and comparable to other high quality a‐Si:H(i) passivation. High‐resolution transmission electron microscopy shows evidence of plasma‐silicon interactions and a sub‐nanometre interfacial layer. Using electron energy‐loss spectroscopy, this layer is further investigated and confirmed to be hydrogenated suboxide layers. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
86.
Ioku Norisuke Ruf Bernhard Terraneo Elide 《Mathematical Physics, Analysis and Geometry》2015,18(1):1-19
We consider a semilinear heat equation with exponential nonlinearity in ?2. We prove that local solutions do not exist for certain data in the Orlicz space exp L 2(?2), even though a small data global existence result holds in the same space exp L 2(?2). Moreover, some suitable subclass of exp L 2(?2) for local existence and uniqueness is proposed.
相似文献87.
Propane‐1,2‐diols from Dilactides,Oligolactides, or Poly‐L‐lactic Acid (PLLA): From Plastic Waste to Chiral Bulk Chemicals
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Dr. Ivan A. Shuklov Dr. Natalia V. Dubrovina Dr. Joachim Schulze Wolfgang Tietz Prof. Dr. Klaus Kühlein Prof. Dr. Armin Börner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(4):957-960
The preparation of racemic or enantioenriched propane‐1,2‐diol from dilactides, oligolactides, or poly‐L ‐lactic acid (PLLA) is described. The transformation is carried out as tandem reactions in MeOH, covering hydrolysis and subsequent hydrogenation by using copper chromite as a catalyst. The starting material present undesired side products of the PLLA synthesis or PLLA waste. 相似文献
88.
Heinrich Henze-Wethkamp Peter Zugenmaier Armin Stein Dieter Klemm 《Macromolecular Symposia》1995,99(1):245-256
In contrast to many cellulose derivatives, the cellulose O-silyl ethers with bulky side groups exhibit scarcely a change in glass transition temperature by a variation of the degree of substitution (DS) or degree of polymerization (DP) or by introducing phenyl carbamate groups for the remaining hydroxyls along the main chain. However, a substitution of these hydroxyls by flexible acetate groups lowers the glass transition temperature considerably. The secondary dispersion (relaxation) behavior is strongly influenced by the various substituents and can be correlated to specific motions of the molecules. The dynamic mechanical properties are also dependent on the kind of preconditioning of the samples. 相似文献
89.
Mario Wolf Alexey Rybakov Richard Hinterding Armin Feldhoff 《Entropy (Basel, Switzerland)》2020,22(11)
Besides the material research in the field of thermoelectrics, the way from a material to a functional thermoelectric (TE) module comes alongside additional challenges. Thus, comprehension and optimization of the properties and the design of a TE module are important tasks. In this work, different geometry optimization strategies to reach maximum power output or maximum conversion efficiency are applied and the resulting performances of various modules and respective materials are analyzed. A Bi2Te3-based module, a half-Heusler-based module, and an oxide-based module are characterized via FEM simulations. By this, a deviation of optimum power output and optimum conversion efficiency in dependence of the diversity of thermoelectric materials is found. Additionally, for all modules, the respective fluxes of entropy and charge as well as the corresponding fluxes of thermal and electrical energy within the thermolegs are shown. The full understanding and enhancement of the performance of a TE module may be further improved. 相似文献