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981.
Jarkko Etula Katja Lahtinen Niklas Wester Ajai Iyer Kai Arstila Timo Sajavaara Tanja Kallio Ulf Helmersson Jari Koskinen 《Advanced functional materials》2019,29(42)
Here, an unidentified type of micropillar growth is described at room temperature during conventional direct‐current magnetron sputtering (DC‐MS) deposition from a Li4Ti5O12+graphite sputter target under negative substrate bias and high operating pressure. These fabricated carbon–Li2O–TiO2 microstructures consisting of various Li4Ti5O12/Li2TiO3/Lix TiO2 crystalline phases are demonstrated as an anode material in Li‐ion microbatteries. The described micropillar fabrication method is a low‐cost, substrate independent, single‐step, room‐temperature vacuum process utilizing a mature industrial complementary metal–oxide–semiconductor (CMOS)‐compatible technology. Furthermore, tentative consideration is given to the effects of selected deposition parameters and the growth process, as based on extensive physical and chemical characterization. Additional studies are, however, required to understand the exact processes and interactions that form the micropillars. If this facile method is further extended to other similar metal oxide–carbon systems, it could offer alternative low‐cost fabrication routes for microporous high‐surface area materials in electrochemistry and microelectronics. 相似文献
982.
Ahlström Christer Wachtmeister Jesper Nyman Mattias Nordenström Axel Kircher Katja 《Cognition, Technology & Work》2020,22(1):181-191
Cognition, Technology & Work - The prevalence of mobile phone usage in traffic has been studied by road-side counting, naturalistic driving data, surveillance cameras, smartphone logging, and... 相似文献
983.
Anik Kumar Ghosh Swagato Sarkar Lisa Julia Nebel Olha Aftenieva Vaibhav Gupta Oliver Sander Amit Das Joby Joseph Sven Wießner Tobias A. F. König Andreas Fery 《Advanced functional materials》2021,31(30):2101959
The next generation of sensors requires a simple yet compact lab on chip-based precise optical detection mechanism where data interpretation can be achieved with minimum effort. Hereby, cost-efficient strategies of manufacturing both propagating surface plasmon polariton (SPP) and localized surface plasmon resonance (LSPR) sensors on flexible platforms are explored via mechanical instabilities and oblique-angled metal evaporation. Centimeter scaled dielectric grating structures produced by plasma oxidation of pre-stressed polydimethylsiloxane film have comprised the substrates, thus imparting inherent flexibility. Subsequently, both continuous and discontinuous 1D-metallic lattices are obtained via vapor deposition of gold at different angles. The optical isotropy (gold surface-grating) and anisotropy (gold edge-grating) are distinctly observed as a difference between forward and backward diffraction efficiencies, backed by analytical correlation to the observed orders. Supported with electromagnetic modeling, the SPP and LSPR excitations are experimentally characterized under reflectance and transmittance measurements, along with a demonstration of their sensing capabilities. The LSPR supported flexible sensor provides superiority in terms of sensitivity, which is investigated under mechanical deformations to exhibit consistency of the resonant wavelength. Such consistency is strategically unraveled via “finite element method” based approaches, thus providing a new paradigm of cost-efficient, large-scaled flexible sensors. 相似文献
984.
985.
986.
Axel Groß 《Topics in Catalysis》2006,37(1):29-39
Bimetallic systems are of special interest in the field of heterogeneous catalysis since they offer the possibility to tailor
the reactivity by preparing specific surface compositions and structures. The reactivity of bimetallic substrates is governed
by an interplay of electronic and geometric effects which are hard to disentangle experimentally. It will be shown that electronic
structure calculations allow to identify the microscopic factors underlying the reactivity of bimetallic systems. Recent first-principles
investigations of the reactivity of bimetallic systems will be presented and the general principles that can be derived from
these studies will be discussed. 相似文献
987.
Daniel Giese Kilian Weiss Bettina Baeßler Navid Madershahian Yeong-Hoon Choi David Maintz Alexander C. Bunck 《Magma (New York, N.Y.)》2018,31(1):165-172
Objectives
The objective of the current work was to evaluate flow and turbulent kinetic energy in different transcatheter aortic valve implants using highly undersampled time-resolved multi-point 3-directional phase-contrast measurements (4D Flow MRI) in an in vitro setup.Materials and methods
A pulsatile flow setup was used with a compliant tubing mimicking a stiff left ventricular outflow tract and ascending aorta. Five different implants were measured using a highly undersampled multi-point 4D Flow MRI sequence. Velocities and turbulent kinetic energy values were analysed and compared.Results
Strong variations of turbulent kinetic energy distributions between the valves were observed. Maximum turbulent kinetic energy values ranged from 100 to over 500 J/m3 while through-plane velocities were similar between all valves.Conclusion
Highly accelerated 4D Flow MRI for the measurement of velocities and turbulent kinetic energy values allowed for the assessment of hemodynamic parameters in five different implant models. The presented setup, measurement protocol and analysis methods provides an efficient approach to compare different valve implants and could aid future novel valve designs.988.
Martine Huberty Katja Tielbörger Jeffrey A. Harvey Caroline Müller Mirka Macel 《Journal of chemical ecology》2016,42(10):1099-1099
989.
In this article, we propose a nonparametric procedure for validating the assumption of stationarity in multivariate locally stationary time series models. We develop a bootstrap‐assisted test based on a Kolmogorov–Smirnov‐type statistic, which tracks the deviation of the time‐varying spectral density from its best stationary approximation. In contrast to all other nonparametric approaches, which have been proposed in the literature so far, the test statistic does not depend on any regularization parameters like smoothing bandwidths or a window length, which is usually required in a segmentation of the data. We additionally show how our new procedure can be used to identify the components where non‐stationarities occur and indicate possible extensions of this innovative approach. We conclude with an extensive simulation study, which shows finite‐sample properties of the new method and contains a comparison with existing approaches. 相似文献
990.
A DNA‐Encoded Library of Chemical Compounds Based on Common Scaffolding Structures Reveals the Impact of Ligand Geometry on Protein Recognition
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Nicholas Favalli Stefan Biendl Marco Hartmann Dr. Jacopo Piazzi Dr. Filippo Sladojevich Dr. Susanne Gräslund Dr. Peter J. Brown Dr. Katja Näreoja Prof. Dr. Herwig Schüler Dr. Jörg Scheuermann Prof. Dr. Raphael Franzini Prof. Dr. Dario Neri 《ChemMedChem》2018,13(13):1303-1307
A DNA‐encoded chemical library (DECL) with 1.2 million compounds was synthesized by combinatorial reaction of seven central scaffolds with two sets of 343×492 building blocks. Library screening by affinity capture revealed that for some target proteins, the chemical nature of building blocks dominated the selection results, whereas for other proteins, the central scaffold also crucially contributed to ligand affinity. Molecules based on a 3,5‐bis(aminomethyl)benzoic acid core structure were found to bind human serum albumin with a Kd value of 6 nm , while compounds with the same substituents on an equidistant but flexible l ‐lysine scaffold showed 140‐fold lower affinity. A 18 nm tankyrase‐1 binder featured l ‐lysine as linking moiety, while molecules based on d ‐Lysine or (2S,4S)‐amino‐l ‐proline showed no detectable binding to the target. This work suggests that central scaffolds which predispose the orientation of chemical building blocks toward the protein target may enhance the screening productivity of encoded libraries. 相似文献