Nikolay V. Shcherbakov  Polina F. Kotikova  Elena I. Chikunova  Dmitry V. Dar'in  Vadim Yu. Kukushkin  Alexey Yu. Dubovtsev 《Advanced Synthesis u0026amp; Catalysis》2023,365(14):2428-2434

Gold-catalyzed interplay between ynamides and aminocarbonyls comprises a route to 2-aminoquinolines. This modular annulation proceeds under relatively mild conditions (Ph₃PAuCl/AgNTf₂ 5 mol %, DCE, 60–80 °C), and a number of functionalities were compatible (42 examples; 25–98% yields). In contrast to a group of other gold-catalyzed methods employing the ynamide/amine combinations for the assembly of 2-aminoquinolines, the developed approach utilizes a diversity of aminocarbonyl substrates and, in particular, allows a variation of the substituents in the 4^th quinoline position. The synthetic potential of the obtained heterocyclic products was illustrated by post-modifications of the quinoline backbone and the peripheral substituents.  相似文献   

    

Gulsana Sissengaliyeva  Fabrice Dénès  Vladilena Girbu  Veaceslav Kulcitki  Elena Hofstetter  Philippe Renaud 《Advanced Synthesis u0026amp; Catalysis》2023,365(15):2568-2576

The direct hydroperfluoroalkylation of a wide range of unactivated alkenes has been achieved at room temperature with readily available iodoperfluoroalkanes using 4-tert-butylcatechol as a source of hydrogen atom and triethylborane. The hydrotrifluoromethylation could also be achieved under these conditions using gaseous trifluoromethyl iodide. An experimentally simple two-step, one-pot hydrotrifluoromethylation process using the easy-to-use trifluoromethanesulfonyl chloride as the source of trifluoromethyl radicals has also been developed. Using these two approaches, a broad range of substrates, including isoprenoid natural products, were efficiently derivatized.  相似文献   

    

Alessia Paganelli  Luisa Benassi  Elena Rossi  Elisabetta Tarentini  Cristina Magnoni 《Microscopy research and technique》2022,85(7):2752-2756

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Miłosz Jeziorski;Wit Derkowski;Elena Michelini; 《Structural Concrete》2024,25(5):3412-3429

Precast prestressed hollow core (HC) floors are widely used in various applications within the construction sector. Such floors are usually designed as single, simply supported elements, although it is known that individual elements forming the floor interact with each other. This article presents the state of the art regarding load redistribution in HC floors in the light of experimental data, current analytical models and code provisions. While this phenomenon is widely known and recognized, only sparse, and often poorly documented experimental data are available, which represent the basis for the assessment and calibration of analytical models. Moreover, even though the available models and code provisions share similar assumptions, their outcomes are in some cases conflicting. Having recognized the existing knowledge gap, the authors outline future perspectives for the development of consistent analytical and numerical approaches supplemented by new experimental data.  相似文献   

    

Mario Ferrara;Diego Gino;Elena Miceli;Luca Giordano;Marzia Malavisi;Gabriele Bertagnoli; 《Structural Concrete》2024,25(3):1637-1657

The assessment of existing reinforced concrete (RC) structures, especially, bridges and viaducts, nowadays is one of the most relevant aspects for infrastructural engineers. Due to the old age of a large part of the railways and roadways assets, their safety, especially, with respect to the Ultimate Limit States (ULS) may result compromised. Safety assessment can be performed following different approaches as well as the most sophisticated methodologies based on the application of safety formats for non-linear finite element (FE) analyses. This study presents the safety assessment at the ULS of existing prestressed RC bridge decks regarding bending moment and axial force failure mechanism adopting different methodologies. Specifically, the safety assessment will be performed through five different approaches (i.e., Courbon theory, elastic FE analysis, and NLFEAs according to the three global safety formats). The decks are modeled using, first, Courbon theory and then, girder FE model composed only of beam elements. The safety assessment is performed by comparing the design resisting moment and design acting moment in the section of interest, therefore, through a local approach. Within the local approach, design values are calculated using the partial safety factors. Afterwards, the decks are modeled with a 3D non-linear FE model. Three different global safety formats are implemented within a global approach. The application of the different approaches leads to significantly different conclusions about the safety assessment. The two local approaches are the most conservative, therefore, lead to a lower safety margin. The application of global approaches based on global safety formats leads to a safety margin gain compared to local approaches, with significant variability in terms of safety margin gain depending on the specific global safety format.  相似文献   

    

Anastasiia Taranova;Edlind Lushaj;Kamran Akbar;Elena Ghedini;Isabel Barroso-Martín;Alessandro Gradone;Vittorio Morandi;Enrique Rodríguez-Castellón;Wenliang Zhu;Elisa Moretti;Alberto Vomiero; 《Solar RRL》2024,8(16):2400198

Inorganic black materials possessing hydrophilicity are scarce but can be of great importance in areas such as solar water evaporation and solar steam generation. Herein, for the first time, transition-metal selenite hydrates (specifically, Earth-abundant metals Ni and Co) not only possess high solar absorbance (>96 %) in the solar spectral range (UV–vis–NIR) but also excellent hydrophilicity, which plays a key role in water transport in the solar steam generation. The hydrophilic behavior in selenite hydrates originates from trapped “water of hydration” inside its crystal lattice, which can easily form hydrogen bonds with other water molecules, facilitating water transport. Owing to the abovementioned properties, the studied selenite hydrates are tested for solar water evaporation, showing excellent water evaporation rates of 1.83 and 2.34 kg m−2 h−1 for nickel selenite hydrate and cobalt selenite hydrate, exceeding the theoretical limit of 1.47 kg m−2 h−1.  相似文献   

    

Yi-Teng Huang;Davide Nodari;Francesco Furlan;Youcheng Zhang;Marin Rusu;Linjie Dai;Zahra Andaji-Garmaroudi;Daniel Darvill;Xiaoyu Guo;Martina Rimmele;Thomas Unold;Martin Heeney;Samuel D. Stranks;Henning Sirringhaus;Akshay Rao;Nicola Gasparini;Robert L. Z. Hoye; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(18):2310199

Solution-processable near-infrared (NIR) photodetectors are urgently needed for a wide range of next-generation electronics, including sensors, optical communications and bioimaging. However, it is rare to find photodetectors with >300 kHz cut-off frequencies, especially in the NIR region, and many of the emerging inorganic materials explored are comprised of toxic elements, such as lead. Herein, solution-processed AgBiS2 photodetectors with high cut-off frequencies under both white light (>1 MHz) and NIR (approaching 500 kHz) illumination are developed. These high cut-off frequencies are due to the short transit distances of charge-carriers in the ultrathin photoactive layer of AgBiS2 photodetectors, which arise from the strong light absorption of this material, such that film thicknesses well below 120 nm are sufficient to absorb >65% of NIR to visible light. It is also revealed that ion migration plays a critical role in the photo-response speed of these devices, and its detrimental effects can be mitigated by finely tuning the thickness of the photoactive layer, which is important for achieving low dark current densities as well. These outstanding characteristics enable the realization of air-stable, real-time heartbeat sensors based on NIR AgBiS2 photodetectors, which strongly motivates their future integration in high-throughput systems.  相似文献   

    

Mehran Ghasemlou;Navya PN;Katia Alexander;Ali Zavabeti;Peter C. Sherrell;Elena P. Ivanova;Benu Adhikari;Minoo Naebe;Suresh K. Bhargava; 《Advanced materials (Deerfield Beach, Fla.)》2024,36(19):2470143

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Elena Luciano Suastegui  Rafael Martinez Caldera  Yasmina Yehia 《Architectural Design》2022,92(1):36-43

Elena Luciano Suastegui, Rafael Martinez Caldera and Yasmina Yehia introduce the Just Transition student project they developed as part of the Landscape Urbanism course at the Architectural Association (AA) in London. The scheme focuses on the coalfields of the South Wales Valleys – areas that were mostly abandoned in the 1980s due to the demise of the UK coal industry, proposing new relationships between community, leisure, work and production to sustainably regenerate these locales.  相似文献   

    

Elena Lloret  Manuel Palomar 《Artificial Intelligence Review》2012,37(1):1-41

This paper contains a large literature review in the research field of Text Summarisation (TS) based on Human Language Technologies (HLT). TS helps users manage the vast amount of information available, by condensing documents’ content and extracting the most relevant facts or topics included in them. The rapid development of emerging technologies poses new challenges to this research field, which still need to be solved. Therefore, it is essential to analyse its progress over the years, and provide an overview of the past, present and future directions, highlighting the main advances achieved and outlining remaining limitations. With this purpose, several important aspects are addressed within the scope of this survey. On the one hand, the paper aims at giving a general perspective on the state-of-the-art, describing the main concepts, as well as different summarisation approaches, and relevant international forums. Furthermore, it is important to stress upon the fact that the birth of new requirements and scenarios has led to new types of summaries with specific purposes (e.g. sentiment-based summaries), and novel domains within which TS has proven to be also suitable for (e.g. blogs). In addition, TS is successfully combined with a number of intelligent systems based on HLT (e.g. information retrieval, question answering, and text classification). On the other hand, a deep study of the evaluation of summaries is also conducted in this paper, where the existing methodologies and systems are explained, as well as new research that has emerged concerning the automatic evaluation of summaries’ quality. Finally, some thoughts about TS in general and its future will encourage the reader to think of novel approaches, applications and lines to conduct research in the next years. The analysis of these issues allows the reader to have a wide and useful background on the main important aspects of this research field.  相似文献