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991.
992.
Colloids for Catalysts: A Concept for the Preparation of Superior Catalysts of Industrial Relevance 下载免费PDF全文
Dr. Jonathan Quinson Sara Neumann Tanja Wannmacher Laura Kacenauskaite Masanori Inaba Jan Bucher Francesco Bizzotto Dr. Søren B. Simonsen Dr. Luise Theil Kuhn Dajana Bujak Dr. Alessandro Zana Prof. Dr. Matthias Arenz Dr. Sebastian Kunz 《Angewandte Chemie (International ed. in English)》2018,57(38):12338-12341
Compared to conventional preparation methods for supported heterogeneous catalysts, the use of colloidal nanoparticles (NPs) allows for a precise control over size, size distribution, and distribution/location of the NPs on the support. However, common colloidal syntheses have restrictions that limit their applicability for industrial catalyst preparation. We present a simple, surfactant‐free, and scalable preparation method for colloidal NPs to overcome these restrictions. We demonstrate how precious‐metal NPs are prepared in alkaline methanol, how the particle size can be tuned, and how supported catalysts are obtained. The potential of these colloids in the preparation of improved catalysts is demonstrated by two examples from heterogeneous catalysis and electrocatalysis. 相似文献
993.
Dissipative Synthetic DNA‐Based Receptors for the Transient Loading and Release of Molecular Cargo 下载免费PDF全文
Dr. Giulio Ragazzon Prof. Leonard J. Prins Prof. Francesco Ricci 《Angewandte Chemie (International ed. in English)》2018,57(33):10489-10493
Supramolecular chemistry is moving into a direction in which the composition of a chemical equilibrium is no longer determined by thermodynamics but by the efficiency with which kinetic states can be populated by energy consuming processes. Herein, we show that DNA is ideally suited for programming chemically fueled dissipative self‐assembly processes. Advantages of the DNA‐based systems presented in this study include a perfect control over the activation site for the chemical fuel in terms of selectivity and affinity, highly selective fuel consumption that occurs exclusively in the activated complex, and a high tolerance for the presence of waste products. Finally, it is shown that chemical fuels can be used to selectively activate different functions in a system of higher complexity embedded with multiple response pathways. 相似文献
994.
Customizing the Electrochemical Properties of Carbon Nanodots by Using Quinones in Bottom‐Up Synthesis 下载免费PDF全文
Francesco Rigodanza Dr. Luka Đorđević Dr. Francesca Arcudi Prof. Maurizio Prato 《Angewandte Chemie (International ed. in English)》2018,57(18):5062-5067
We show how the redox potentials of carbon nanodots (CNDs) can be modulated by employing quinones as electroactive precursors during a microwave‐assisted synthesis. We prepared and characterized a redox library of CNDs, demonstrating that this approach can promote the use of carbon nanodots for ad hoc applications, including photocatalysis. 相似文献
995.
General scheme of enantiomeric molecular imprinting. Reprinted from [21?] with permission from Elsevier. 相似文献
996.
Advances in Data Analysis and Classification - We analyze the changing attitudes toward immigration in EU host countries in the last few years (2010–2018) on the basis of the European Social... 相似文献
997.
Francesco Baldassarri 《Transactions of the American Mathematical Society》1996,348(6):2249-2289
We discuss the -adic formula (0.3) of P. Th. Young, in the framework of Dwork's theory of the hypergeometric equation. We show that it gives the value at 0 of the Frobenius automorphism of the unit root subcrystal of the hypergeometric crystal. The unit disk at 0 is in fact singular for the differential equation under consideration, so that it's not a priori clear that the Frobenius structure should extend to that disk. But the singularity is logarithmic, and it extends to a divisor with normal crossings relative to in . We show that whenever the unit root subcrystal of the hypergeometric system has generically rank 1, it actually extends as a logarithmic -subcrystal to the unit disk at 0. So, in these optics, ``singular classes are not supersingular'. If, in particular, the holomorphic solution at 0 is bounded, the extended logarithmic -crystal has no singularity in the residue class of 0, so that it is an -crystal in the usual sense and the Frobenius operation is holomorphic. We examine in detail its analytic form.
998.
This work was carried out when the last named author visited the Department of Mathematics of the University of Napoli Federico II in March 1994. He is very grateful for the hospitality he enjoyed and for the support by the C.N.R. 相似文献
999.
Silvana Franciosi Francesco de Giovanni 《Proceedings of the American Mathematical Society》1997,125(2):323-327
A subgroup of a group is said to be normal-by-finite if the core of in has finite index in . In this article groups satisfying the minimal condition on subgroups which are not normal-by-finite and groups with finitely many conjugacy classes of subgroups which are not normal-by-finite are characterized.
1000.
Francesco Pappalardi. 《Mathematics of Computation》1997,66(218):853-868
We assume the generalized Riemann hypothesis and prove an asymptotic formula for the number of primes for which can be generated by given multiplicatively independent numbers. In the case when the given numbers are primes, we express the density as an Euler product and apply this to a conjecture of Brown-Zassenhaus (J. Number Theory 3 (1971), 306-309). Finally, in some examples, we compare the densities approximated with the natural densities calculated with primes up to .