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排序方式: 共有690条查询结果,搜索用时 31 毫秒
101.
Yokoyama Daniel Schulze Bruno Borges Fábio Mc Evoy Giacomo 《The Journal of supercomputing》2019,75(10):7003-7036
The Journal of Supercomputing - The ongoing effort to reach the exascale computing barrier has led to a myriad of research and publications in the topic of alternative energy-efficient... 相似文献
102.
Qingzhe Zhang Shengyun Huang Jiujun Deng Deepak Thrithamarassery Gangadharan Fan Yang Zhenhe Xu Giacomo Giorgi Maurizia Palummo Mohamed Chaker Dongling Ma 《Advanced functional materials》2019,29(28)
A 2D/2D heterojunction of black phosphorous (BP)/graphitic carbon nitride (g‐C3N4) is designed and synthesized for photocatalytic H2 evolution. The ice‐assisted exfoliation method developed herein for preparing BP nanosheets from bulk BP, leads to high yield of few‐layer BP nanosheets (≈6 layers on average) with large lateral size at reduced duration and power for liquid exfoliation. The combination of BP with g‐C3N4 protects BP from oxidation and contributes to enhanced activity both under λ > 420 nm and λ > 475 nm light irradiation and to long‐term stability. The H2 production rate of BP/g‐C3N4 (384.17 µmol g?1 h?1) is comparable to, and even surpasses that of the previously reported, precious metal‐loaded photocatalyst under λ > 420 nm light. The efficient charge transfer between BP and g‐C3N4 (likely due to formed N? P bonds) and broadened photon absorption (supported both experimentally and theoretically) contribute to the excellent photocatalytic performance. The possible mechanisms of H2 evolution under various forms of light irradiation is unveiled. This work presents a novel, facile method to prepare 2D nanomaterials and provides a successful paradigm for the design of metal‐free photocatalysts with improved charge‐carrier dynamics for renewable energy conversion. 相似文献
103.
Tommaso Marchesi D'Alvise Sean Harvey Lisa Hueske Jolanta Szelwicka Lothar Veith Tuomas P. J. Knowles Dennis Kubiczek Carolin Flaig Fabian Port Kay‐E. Gottschalk Frank Rosenau Bartlomiej Graczykowski George Fytas Francesco S. Ruggeri Katrin Wunderlich Tanja Weil 《Advanced functional materials》2020,30(21)
Cellular membranes have long served as an inspiration for nanomaterial research. The preparation of ultrathin polydopamine (PDA) films with integrated protein pores containing phospholipids and an embedded domain of a membrane protein glycophorin A as simplified cell membrane mimics is reported. Large area, ultrathin PDA films are obtained by electropolymerization on gold surfaces with 10–18 nm thickness and dimensions of up to 2.5 cm2. The films are transferred from gold to various other substrates such as nylon mesh, silicon, or substrates containing holes in the micrometer range, and they remain intact even after transfer. The novel transfer technique gives access to freestanding PDA films that remain stable even at the air interfaces with elastic moduli of ≈6–12 GPa, which are higher than any other PDA films reported before. As the PDA film thickness is within the range of cellular membranes, monodisperse protein nanopores, so‐called “nanodiscs,” are integrated as functional entities. These nanodisc‐containing PDA films can serve as semi‐permeable films, in which the embedded pores control material transport. In the future, these simplified cell membrane mimics may offer structural investigations of the embedded membrane proteins to receive an improved understanding of protein‐mediated transport processes in cellular membranes. 相似文献
104.
Corvin Rive Giacomo Reina Prerana Wagle Emanuele Treossi Vincenzo Palermo Alberto Bianco Lucia Gemma Delogu Matthias Rieckher Bjrn Schumacher 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(45)
Graphene oxide (GO) holds high promise for diagnostic and therapeutic applications in nanomedicine but reportedly displays immunotoxicity, underlining the need for developing functionalized GO with improved biocompatibility. This study describes adverse effects of GO and amino‐functionalized GO (GONH2) during Caenorhabditis elegans development and ageing upon acute or chronic exposure. Chronic GO treatment throughout the C. elegans development causes decreased fecundity and a reduction of animal size, while acute treatment does not lead to any measurable physiological decline. However, RNA‐Sequencing data reveal that acute GO exposure induces innate immune gene expression. The p38 MAP kinase, PMK‐1, which is a well‐established master regulator of innate immunity, protects C. elegans from chronic GO toxicity, as pmk‐1 mutants show reduced tissue‐functionality and facultative vivipary. In a direct comparison, GONH2 exposure does not cause detrimental effects in the wild type or in pmk‐1 mutants, and the innate immune response is considerably less pronounced. This work establishes enhanced biocompatibility of amino‐functionalized GO in a whole‐organism, emphasizing its potential as a biomedical nanomaterial. 相似文献
105.
Sara Sassetti Giacomo Marzi Vincenzo Cavaliere Cristiano Ciappei 《Scientometrics》2018,116(3):1675-1718
Research on entrepreneurial cognition (EC) has evolved in recent years, and the aim of this contribution is to offer a clear, systematic, and bibliometric review of EC as a field of study from a more dynamic perspective, building on Socially Situated Cognition theory (SSC). Based on a data set that covers 18 years of research, from 1998 to 2016, the present study analyzes all of the 151 papers available in the Web of Science Core Collection and 15 editorials, book chapters, and books directly referring to entrepreneurial cognition. Building on our results, we divided EC studies into two stages, namely the “emerging” (1998–2007) and the “mature” (2008–2016). In addition, with this study we suggest three main topics that should be investigated in future researches: entrepreneurial action should be considered endogenous in the entrepreneurship process and the studies in the field of embodied and distributed cognition should be expanded. 相似文献
106.
Electroactive Ionic Soft Actuators with Monolithically Integrated Gold Nanocomposite Electrodes
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Yunsong Yan Tommaso Santaniello Luca Giacomo Bettini Chloé Minnai Andrea Bellacicca Riccardo Porotti Ilaria Denti Gabriele Faraone Marco Merlini Cristina Lenardi Paolo Milani 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Electroactive ionic gel/metal nanocomposites are produced by implanting supersonically accelerated neutral gold nanoparticles into a novel chemically crosslinked ion conductive soft polymer. The ionic gel consists of chemically crosslinked poly(acrylic acid) and polyacrylonitrile networks, blended with halloysite nanoclays and imidazolium‐based ionic liquid. The material exhibits mechanical properties similar to that of elastomers (Young's modulus ≈ 0.35 MPa) together with high ionic conductivity. The fabrication of thin (≈100 nm thick) nanostructured compliant electrodes by means of supersonic cluster beam implantation (SCBI) does not significantly alter the mechanical properties of the soft polymer and provides controlled electrical properties and large surface area for ions storage. SCBI is cost effective and suitable for the scaleup manufacturing of electroactive soft actuators. This study reports the high‐strain electromechanical actuation performance of the novel ionic gel/metal nanocomposites in a low‐voltage regime (from 0.1 to 5 V), with long‐term stability up to 76 000 cycles with no electrode delamination or deterioration. The observed behavior is due to both the intrinsic features of the ionic gel (elasticity and ionic transport capability) and the electrical and morphological features of the electrodes, providing low specific resistance (<100 Ω cm?2), high electrochemical capacitance (≈mF g?1), and minimal mechanical stress at the polymer/metal composite interface upon deformation. 相似文献
107.
Gaetano Alfano Francesco Fontana Niccolò Morisi Francesco Giaroni Giacomo Mori Giovanni Guaraldi Riccardo Magistroni Gianni Cappelli Modena Covid- Working Group 《Hemodialysis international. International Symposium on Home Hemodialysis》2021,25(4):E53-E56
The immunological mechanisms that modulate immune response to SARS-CoV-2 infection remain elusive. Little is known on the magnitude and the durability of antibody response against COVID-19. There is consensus that patients with immune dysfunction, such as dialysis patients, may be unable to mount a robust and durable humoral immunity after infections. Recent studies showed that dialysis patients seroconverted after COVID-19, but data on the durability of the immune response are missing. We reported the data of a durable anti-spike protein seroconversion after natural SARS-CoV-2 infection in three patients on hemodialysis with a mean age of 67.2 ± 13.8 years. A mean antibody titer of 212.6 ± 174.9 UA/ml (Liaison®, DiaSorin) was found after one year (range, 366–374 days) from the diagnosis of COVID-19. In conclusion, this case series provided evidence that patients receiving hemodialysis who recovered from severe COVID-19 were able to mount a long-lasting immune response against SARS-CoV-2. Although the protective capacity of this long-term immunity remains to be determined, these patients did not report signs of reinfection after recovery from COVID-19. 相似文献
108.
Ciampi Francesco Giannozzi Alessandro Marzi Giacomo Altman Edward I. 《Scientometrics》2021,126(3):2141-2188
Scientometrics - Over the last dozen years, the topic of small and medium enterprise (SME) default prediction has developed into a relevant research domain that has grown for important reasons... 相似文献
109.
Zahra Andaji‐Garmaroudi Mojtaba Abdi‐Jalebi Dengyang Guo Stuart Macpherson Aditya Sadhanala Elizabeth M. Tennyson Edoardo Ruggeri Miguel Anaya Krzysztof Galkowski Ravichandran Shivanna Kilian Lohmann Kyle Frohna Sebastian Mackowski Tom J. Savenije Richard H. Friend Samuel D. Stranks 《Advanced materials (Deerfield Beach, Fla.)》2019,31(42)
Mixed‐halide lead perovskites have attracted significant attention in the field of photovoltaics and other optoelectronic applications due to their promising bandgap tunability and device performance. Here, the changes in photoluminescence and photoconductance of solution‐processed triple‐cation mixed‐halide (Cs0.06MA0.15FA0.79)Pb(Br0.4I0.6)3 perovskite films (MA: methylammonium, FA: formamidinium) are studied under solar‐equivalent illumination. It is found that the illumination leads to localized surface sites of iodide‐rich perovskite intermixed with passivating PbI2 material. Time‐ and spectrally resolved photoluminescence measurements reveal that photoexcited charges efficiently transfer to the passivated iodide‐rich perovskite surface layer, leading to high local carrier densities on these sites. The carriers on this surface layer therefore recombine with a high radiative efficiency, with the photoluminescence quantum efficiency of the film under solar excitation densities increasing from 3% to over 45%. At higher excitation densities, nonradiative Auger recombination starts to dominate due to the extremely high concentration of charges on the surface layer. This work reveals new insight into phase segregation of mixed‐halide mixed‐cation perovskites, as well as routes to highly luminescent films by controlling charge density and transfer in novel device structures. 相似文献
110.
Daniele Costa Giacomo Palmieri Matteo-Claudio Palpacelli Luca Panebianco David Scaradozzi 《Journal of Intelligent and Robotic Systems》2018,91(2):181-192
The following paper presents the design and fabrication of an ostraciiform swimming robot and its navigation control and guidance system. Compared to other biomimetic vehicles, the chosen architecture has a lower propulsive efficiency but is easier to waterproof and capable to withstand greater pressures. To generate the alternating motion of the robot bio-inspired thruster, namely a plane fin, a transmission system was designed to replace the direct drive widely adopted in underwater biomimetic vehicles. The mechanical efficiency of two alternative mechanisms capable to actuate the fin were computed according to a preliminary sizing of the robot and its targeted swimming performances. Therefore, the more suitable solution was manufactured and installed aboard. At the same time, a proper navigation, guidance and control architecture (NGC) was designed and then integrated in the robot main controller. The proposed solution allows the vehicle to perform different missions autonomously once their profiles are received from the base station. Preliminary tests results and future works are discussed in the final conclusions. 相似文献