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排序方式: 共有711条查询结果,搜索用时 15 毫秒
91.
92.
Rafael Schmitt Markus Kubicek Eva Sediva Morgan Trassin Mads C. Weber Antonella Rossi Herbert Hutter Jens Kreisel Manfred Fiebig Jennifer L. M. Rupp 《Advanced functional materials》2019,29(5)
Memristive devices based on mixed ionic–electronic resistive switches have an enormous potential to replace today's transistor‐based memories and Von Neumann computing architectures thanks to their ability for nonvolatile information storage and neuromorphic computing. It still remains unclear however how ionic carriers are propagated in amorphous oxide films at high local electric fields. By using memristive model devices based on LaFeO3 with either amorphous or epitaxial nanostructures, we engineer the structural local bonding units and increase the oxygen‐ionic diffusion coefficient by one order of magnitude for the amorphous oxide, affecting the resistive switching operation. We show that only devices based on amorphous LaFeO3 films reveal memristive behavior due to their increased oxygen vacancy concentration. We achieved stable resistive switching with switching times down to microseconds and confirm that it is predominantly the oxygen‐ionic diffusion character and not electronic defect state changes that modulate the resistive switching device response. Ultimately, these results show that the local arrangement of structural bonding units in amorphous perovskite films at room temperature can be used to largely tune the oxygen vacancy (defect) kinetics for resistive switches (memristors) that are both theoretically challenging to predict and promising for future memory and neuromorphic computing applications. 相似文献
93.
This paper presents the design of a new adaptive optimization‐based second‐order sliding mode control algorithm for uncertain nonlinear systems. It is designed on the basis of a second‐order sliding mode control with optimal reaching, with the aim of reducing the control effort while maintaining all the positive aspects in terms of finite‐time convergence and robustness in front of matched uncertainties. These features are beneficial to guarantee good performance in case of vehicle dynamics control, a crucial topic in the light of the increasing demand of semiautonomous and autonomous driving capabilities in commercial vehicles. The new proposal is theoretically analyzed, as well as verified relying on an extensive comparative study, carried out on a realistic simulator of a 4‐wheeled vehicle, in the case of a lateral stability control system. 相似文献
94.
95.
Maria Carmela Annosi Alberto Monti Antonella Martini 《Creativity & Innovation Management》2020,29(3):528-545
Previous research has shown the importance of individual learning goal orientation for both job and task performance and consequently organizational performance. Despite its importance, knowledge on the antecedents of learning goal orientation remains scarce, especially in the context of self‐managing team‐based organizations. In fact, most of the research on goal orientation antecedents has been focused on individual characteristics, belief, and ability, while the contextual factors that might influence them remain unspecified. We build on and further extend earlier studies by jointly exploring the role of individual and contextual factors affecting individual learning orientation. In particular, this study combines individual informal social network, self‐efficacy, performance feedbacks, and team identification into a model that explains individuals' learning goal orientation within self‐managing team‐based organizations. The model was empirically tested on a sample of 104 individuals belonging to an R&D organization relying on self‐managing teams. Results show that performance feedback has a negative direct effect, while team identification has a positive direct effect on individual learning goal orientation. In addition, we found that individual self‐efficacy is a mediator of the relationships between performance feedback and brokerage in the advice network and individual learning goal orientation. Finally, we did not find a relationship between centrality in the friendship network and individual learning goal orientation. 相似文献
96.
97.
Structure–Activity Relationships of Benzenesulfonamide‐Based Inhibitors towards Carbonic Anhydrase Isoform Specificity 下载免费PDF全文
Avni Bhatt Dr. Brian P. Mahon Vinicius Wilian D. Cruzeiro Dr. Benedetta Cornelio Dr. Marie Laronze‐Cochard Dr. Mariangela Ceruso Prof. Dr. Janos Sapi Dr. Graham A. Rance Prof. Dr. Andrei N. Khlobystov Assoc. Prof. Dr. Antonella Fontana Prof. Dr. Adrian Roitberg Prof. Dr. Claudiu T. Supuran Prof. Dr. Robert McKenna 《Chembiochem : a European journal of chemical biology》2017,18(2):213-222
Carbonic anhydrases (CAs) are implicated in a wide range of diseases, including the upregulation of isoforms CA IX and XII in many aggressive cancers. However, effective inhibition of disease‐implicated CAs should minimally affect the ubiquitously expressed isoforms, including CA I and II, to improve directed distribution of the inhibitors to the cancer‐associated isoforms and reduce side effects. Four benzenesulfonamide‐based inhibitors were synthesized by using the tail approach and displayed nanomolar affinities for several CA isoforms. The crystal structures of the inhibitors bound to a CA IX mimic and CA II are presented. Further in silico modeling was performed with the inhibitors docked into CA I and XII to identify residues that contributed to or hindered their binding interactions. These structural studies demonstrated that active‐site residues lining the hydrophobic pocket, especially positions 92 and 131, dictate the positional binding and affinity of inhibitors, whereas the tail groups modulate CA isoform specificity. Geometry optimizations were performed on each ligand in the crystal structures and showed that the energetic penalties of the inhibitor conformations were negligible compared to the gains from active‐site interactions. These studies further our understanding of obtaining isoform specificity when designing small molecule CA inhibitors. 相似文献
98.
Gottardini E Cristofori A Cristofolini F Maccherini S Ferretti M 《The Science of the total environment》2008,402(2-3):299-305
A fully randomized sampling design was adopted to test whether pollen viability of Austrian pine (Pinus nigra Arnold) was impacted by NO(2) pollution. Spatial strata (500500 m each) with high (41.9-44.6 microg m(-3)) and low (15.4-21.0 microg m(-3)) NO(2) were selected from a defined population in a small area (236.5 km(2), <200 m range in elevation) in Northern Italy. Pollen viability was measured by means of the Tetrazolium (TTC) test. Analysis of variance by means of a generalised linear model showed that NO(2) was a significant factor (P=0.0425) affecting pollen viability. Within the treatment, no significant differences were detected among replicates. Within each replicate, sampling unit data were significantly different (P=0.000) and this suggested some improvement in the applied sampling design was needed. Pollen viability was significantly related to pollen germination (P<0.01) and tube length (P<0.01). This suggested a possible impact of NO(2) on the regeneration of Austrian pine in polluted environments. 相似文献
99.
Salvatore Mellino Antonella Petrillo Viviana Cigolotti Claudio Autorino Elio Jannelli Sergio Ulgiati 《International Journal of Hydrogen Energy》2017,42(3):1830-1840
Smart mobility is day by day becoming one of the crucial issues to address in order to reduce environmental impacts such as global warming, acidification, photochemical smog, among others. The growing concerns about urban air quality are the driving force for cleaner and more efficient transport systems. Several new transport technologies are being developed, in particular concerning electric vehicles, considered a suitable solution to urban air pollution problems. However, these vehicles require electric and electronic devices that might give rise to a new set of environmental problems in their production, operation and disposal phases. Are electric vehicles a really cleaner solution? This paper aims at answering this question, by comparing two kinds of vehicle, a lithium battery powered electric bike and a hydrogen-fuel cell operated one, using internal combustion engine vehicles as benchmark. The fuel cell bike uses a proton exchange membrane fuel cell (PEMFC) to convert hydrogen into electricity. In this study, Life Cycle Assessment is applied to evaluate the environmental burdens of the production of these two vehicles and compare their environmental performances per 100 km travelled. The study, not only includes vehicle road operation but also embraces production and distribution of bikes, electric battery, PEMFC and energy carriers (electricity and hydrogen) over the vehicle's entire lifetime. The LCA evaluation of the vehicle production phases shows that the construction of the H-bike results more impacting than the E-bike in all the considered categories due to the presence of more complex components technology. Instead, when the boundary is shifted to the operational phases of the vehicles including the energy carriers production, the situation is reversed and the environmental performance of the H-bike results better than the one of E-bike. 相似文献
100.
Antonella Marone Olga R. Ayala-Campos Eric Trably Alessandro A. Carmona-Martínez Roman Moscoviz Eric Latrille Jean-Philippe Steyer Víctor Alcaraz-Gonzalez Nicolas Bernet 《International Journal of Hydrogen Energy》2017,42(3):1609-1621
The aim of this work is to evaluate biohydrogen production from agro-industrial wastewaters and by-products, by combining dark fermentation and microbial electrolysis in a two-step cascade process. Such coupling of both technologies constitutes a technological building block within a concept of environmental biorefinery where sustainable production of renewable energy is expected.Six different wastewaters and industrial by-products coming from cheese, fruit juice, paper, sugar, fruit processing and spirits factories were evaluated for the feasibility of hydrogen production in a two-step process. The overall hydrogen production when coupling dark fermentation and microbial electrolysis was increased up to 13 times when compared to fermentation alone, achieving a maximum overall hydrogen yield of 1608.6 ± 266.2 mLH2/gCODconsumed and a maximum of 78.5 ± 5.7% of COD removal.These results show that dark fermentation coupled with microbial electrolysis is a highly promising option to maximize the conversion of agro-industrial wastewaters and by-products into bio-hydrogen. 相似文献